tag:theconversation.com,2011:/ca/topics/plant-science-5601/articlesPlant science – The Conversation2023-11-09T13:32:30Ztag:theconversation.com,2011:article/2163262023-11-09T13:32:30Z2023-11-09T13:32:30ZCranberries can bounce, float and pollinate themselves: The saucy science of a Thanksgiving classic<figure><img src="https://images.theconversation.com/files/558166/original/file-20231107-21-cmo43c.jpg?ixlib=rb-1.1.0&rect=15%2C9%2C2029%2C1140&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cranberries grow on vines in sandy bogs and marshes.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/Mm6QhN">Lance Cheung, USDA/Flickr</a></span></figcaption></figure><p>Cranberries are a staple in U.S. households at Thanksgiving – but how did this bog dweller end up on holiday tables? </p>
<p>Compared to many valuable plant species that were domesticated over thousands of years, cultivated cranberry (<em>Vaccinium macrocarpon</em>) is a young agricultural crop, just as the U.S. is a young country and Thanksgiving is <a href="https://theconversation.com/how-advertising-shaped-thanksgiving-as-we-know-it-86819">a relatively new holiday</a>. But <a href="https://soilcrop.tamu.edu/people/desalvio-serina/">as a plant scientist</a>, I’ve learned much about cranberries’ ancestry from their botany and genomics.</p>
<h2>New on the plant breeding scene</h2>
<p>Humans have cultivated <a href="https://doi.org/10.1007/s10437-018-9314-2">sorghum for some 5,500 years</a>, <a href="https://www.nsf.gov/news/news_summ.jsp?cntn_id=114445">corn for around 8,700 years</a> and <a href="https://doi.org/10.1534/g3.120.401362">cotton for about 5,000 years</a>. In contrast, cranberries were domesticated around 200 years ago – but people were eating the berries before that.</p>
<p>Wild cranberries are native to North America. They were an important food source for Native Americans, who used them in puddings, sauces, breads and a <a href="https://www.cranberries.org/exploringcranberries/into/maki_back.html">high-protein portable food called pemmican</a> – a carnivore’s version of an energy bar, made from a mixture of dried meat and rendered animal fat and sometimes studded with dried fruits. Some tribes <a href="https://lakotarednations.com/2017/11/wo-lakota-making-wasna/">still make pemmican today</a>, and even <a href="https://tankabar.com/">market a commercial version</a>. </p>
<p>Cranberry cultivation began in 1816 in Massachusetts, where Revolutionary War veteran Henry Hall found that <a href="https://www.youtube.com/watch?v=nt7NA7G808Y&t=5s">covering cranberry bogs with sand</a> fertilized the vines and retained water around their roots. From there, the fruit spread throughout the U.S. Northeast and Upper Midwest. </p>
<p>Today, <a href="https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=102649">Wisconsin produces roughly 60%</a> of the U.S. cranberry harvest, followed by Massachusetts, Oregon and New Jersey. Cranberries also are grown in Canada, where they are <a href="https://canadianfoodfocus.org/in-season/whats-in-season-cranberries/">a major fruit crop</a>.</p>
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<a href="https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Four men in waders, holding long rakes, thigh-deep in a flooded bog, its surface covered with floating cranberries." src="https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=305&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=305&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=305&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=383&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=383&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558168/original/file-20231107-29-f3xdq7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=383&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Farmers often flood cranberry bogs to harvest the fruit, which they rake loose from the vines.</span>
<span class="attribution"><a class="source" href="https://flic.kr/p/bBmqts">Michael Galvin, Massachusetts Office of Travel and Tourism/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<h2>A flexible and adaptable plant</h2>
<p>Cranberries have many interesting botanical features. Like roses, lilies and daffodils, cranberry flowers are hermaphroditic, which means they <a href="https://www.gardeningknowhow.com/garden-how-to/info/hermaphroditic-plant-information.htm">contain both male and female parts</a>. This allows them to self-pollinate instead of relying on birds, insects or other pollinators. </p>
<p>A cranberry blossom has four petals that peel back when the flower blooms. This exposes the anthers, which contain the plant’s pollen. The flower’s resemblance to the beak of a bird earned the cranberry its original name, <a href="https://gobotany.nativeplanttrust.org/species/vaccinium/macrocarpon/">the “craneberry</a>.” </p>
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<a href="https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A flower with four curved white petals tinged with pink." src="https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=742&fit=crop&dpr=1 600w, https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=742&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=742&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=932&fit=crop&dpr=1 754w, https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=932&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/558169/original/file-20231107-23-zvban6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=932&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A blossom on a cranberry bush in Wisconsin.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Cranberry_Blossom_%289180939392%29.jpg">Aaron Carlson/Wikimedia</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
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<p>When cranberries don’t self-pollinate, they rely on bumblebees and honeybees to transport their pollen from flower to flower. They can also be propagated sexually, by planting seeds, or asexually, through rooting vine cuttings. This is important for growers because seed-based propagation allows for higher genetic diversity, which can translate to things like increased disease resistance or more pest tolerance. </p>
<p>Asexual reproduction is equally important, however. This method allows growers to create clones of varieties that perform very well in their bogs and grow even more of those high-performing types.</p>
<p>Every cranberry <a href="https://www.wisfarmer.com/story/news/2018/07/13/farm-technology-days-five-fun-cranberry-facts/784392002/">contains four air pockets</a>, which is why they float when farmers flood bogs to harvest them. The air pockets also make raw cranberries bounce when they are dropped on a hard surface – a good indicator of whether they are fresh.</p>
<p>These pockets serve a biological role: They enable the berries to float down rivers and streams to disperse their seeds. Many other plants disperse their seeds via animals and birds that eat their fruits and excrete the seeds as they move around. But as anyone who has tasted them raw knows, cranberries are ultra-tart, so they have <a href="https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_viopa2.pdf">limited appeal for wildlife</a>. </p>
<h2>Reading cranberry DNA</h2>
<p>For cranberries being such a young crop, scientists already know <a href="https://doi.org/10.1002/9781119616801.ch8">a lot about their genetics</a>. The cranberry <a href="https://www.genome.gov/genetics-glossary/Diploid">is a diploid</a>, which means that each cell contains one set of chromosomes from the maternal parent and one set from the paternal parent. It has 24 chromosomes, and its genome size is less than one-tenth that of the human genome. </p>
<p>Insights like these help scientists better understand where potentially valuable genes might be located in the cranberry genome. And diploid crops tend to have fewer genes associated with a single trait, which makes breeding them to emphasize that trait much simpler. </p>
<p>Researchers have also described the genetics of the cultivated cranberry’s wild relative, which is known as the “<a href="https://plants.usda.gov/DocumentLibrary/plantguide/pdf/cs_vaox.pdf">small cranberry” (<em>Vaccinium oxycoccos</em>)</a>. Comparing the two can help scientists determine where the cultivated cranberry’s agronomically valuable traits reside in its genome, and where some of the small cranberry’s cold hardiness might come from. </p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/p/CxGCZq0xv16/?utm_source=ig_web_copy_link","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<p>Researchers are <a href="https://www.vacciniumcap.org/">developing molecular markers</a> – tools to determine where certain genes or sequences of interest reside within a genome – to help determine the best combinations of genes from different varieties of cranberry that can enhance desired traits. For example, a breeder might want to make the fruits larger, more firm or redder in color.</p>
<p>While cranberries have only been grown by humans for a short period of time, they have been evolving for much longer. They entered agriculture with a long genetic history, including things like <a href="https://doi.org/10.1371/journal.pone.0264966">whole genome duplication events and genetic bottlenecks</a>, which collectively change which genes are gained or lost over time in a population. </p>
<p>Whole genome duplication events occur when two species’ genomes collide to form a new, larger genome, encompassing all the traits of the two parental species. Genetic bottlenecks occur when a population is greatly reduced in size, which limits the amount of genetic diversity in that species. These events are extremely common in the plant world and can lead to both gains and losses of different genes. </p>
<p>Analyzing the cranberry’s genome can indicate when it diverged evolutionarily from some of its relatives, such as the blueberry, lingonberry and huckleberry. Understanding <a href="https://theconversation.com/modern-tomatoes-are-very-different-from-their-wild-ancestors-and-we-found-missing-links-in-their-evolution-130041">how modern species evolved</a> can teach plant scientists about how different traits are inherited, and how to effectively breed for them in the future.</p>
<h2>Ripe at the right time</h2>
<p>Cranberries’ close association with Thanksgiving was simply a practical matter at first. Fresh cranberries are ready to harvest from mid-September through mid-November, so Thanksgiving falls within that perfect window for eating them. </p>
<p>Cranberry sauce was first loosely described in accounts from the American colonies in the 1600s, and appeared in a <a href="https://www.smithsonianmag.com/history/what-americas-first-cookbook-says-about-our-country-its-cuisine-180967809/">cookbook for the first time in 1796</a>. The berries’ tart flavor, which comes from <a href="https://rucore.libraries.rutgers.edu/rutgers-lib/60677/">high levels of several types of acids</a>, makes them more than twice as acidic as most other edible fruits, so they add a welcome zing to a meal full of blander foods like turkey and potatoes.</p>
<p>In recent decades, the cranberry industry has branched out into <a href="https://theconversation.com/can-cranberries-conquer-the-world-a-us-industry-depends-on-it-87912">juices, snacks and other products</a> in pursuit of year-round markets. But for many people, Thanksgiving is still the time when they’re most likely to see cranberries in some form on the menu.</p><img src="https://counter.theconversation.com/content/216326/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Serina DeSalvio does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Cranberries add color and acidity to Thanksgiving menus, but they also have many interesting botanical and genetic features.Serina DeSalvio, Ph.D. Candidate in Genetics and Genomics, Texas A&M UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2106162023-09-20T12:25:33Z2023-09-20T12:25:33ZTake a break from your screen and look at plants − botanizing is a great way to engage with life around you<figure><img src="https://images.theconversation.com/files/548424/original/file-20230914-27-ilf6bk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">You may be surprised by what's growing on a familiar trail.</span> <span class="attribution"><span class="source">Benjamin Goulet-Scott</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span></figcaption></figure><p>When you hear about the abundance of life on Earth, what do you picture? For many people, it’s animals – but awareness of plant diversity is growing rapidly.</p>
<p>Our planet has <a href="https://www.mobot.org/mobot/research/apweb/">nearly 300,000 species of flowering plants</a>. Among animals, only beetles can compete with that number. There are more species of ferns than birds, more mints than mammals, and more beans than butterflies. Measured in total mass, plants make up <a href="https://doi.org/10.1073/pnas.1711842115">82% of all life on land across the globe</a>.</p>
<p>We are plant scientists and co-founders of <a href="https://www.letsbotanize.org/">Let’s Botanize</a>, an educational nonprofit that uses plant life to teach about ecology, evolution and biodiversity. In the past several years we have witnessed a <a href="https://doi.org/10.1002/ppp3.10257">botanical boom</a>, with <a href="https://theconversation.com/the-pandemics-gardening-boom-shows-how-gardens-can-cultivate-public-health-181426">participation in plant-based hobbies surging</a>. From cultivating houseplants to foraging for wild foods and <a href="https://www.fox10phoenix.com/news/over-2-in-5-us-households-now-growing-food-following-pandemic-boom">outdoor gardening</a>, plant appreciation is on the rise.</p>
<p><a href="https://www.merriam-webster.com/dictionary/botanize">Botanizing</a> is spending time alongside plants in order to observe and appreciate them as living organisms – like birding, but with subjects that stay in place. When you botanize, a simple walk in the woods becomes an immersive experience shared with many species. Getting to know your nonhuman neighbors is a way to engage with a changing planet.</p>
<p><div data-react-class="InstagramEmbed" data-react-props="{"url":"https://www.instagram.com/reel/Cw2xvLgO-u9/?hl=en","accessToken":"127105130696839|b4b75090c9688d81dfd245afe6052f20"}"></div></p>
<h2>Plant collecting and colonialism</h2>
<p>Botanizing has a deep and checkered history. Humans have been analyzing and classifying plants for <a href="https://huh.harvard.edu/book/chapter-2-brief-history">thousands of years</a>, often to figure out what they can safely eat or cultivate. </p>
<p>When Europeans began exploring and colonizing other parts of the world, they were interested in finding plants that were useful as food, medicine or for other purposes. For example, in the early 17th century, the Dutch East India Company <a href="https://historibersama.com/the-voc-genocide-historia/">forcibly colonized the Banda Islands</a> in what is now Indonesia in order to monopolize the cultivation and lucrative trade of nutmeg (<em>Myristica fragrans</em>).</p>
<p>In 19th-century England, Victorians became obsessed with plants, especially ferns. This craze came to be known as <a href="https://www.historic-uk.com/CultureUK/Pteridomania-Fern-Madness/">pteridomania, or fern fever</a>. It coincided with the height of European imperialism across the globe, which included widespread collection of valuable plants from faraway places. </p>
<p>Today, however, many botanic gardens and <a href="http://arbnet.org/whats-arboretum">arboreta</a> – gardens that focus on trees and shrubs – have shifted their mission to public education, scientific research and biodiversity conservation. They can be good resources for learning to botanize.</p>
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<figcaption><span class="caption">An estimated 40% of the world’s plant species are at risk of extinction, including many that haven’t yet been identified.</span></figcaption>
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<h2>Why botanize?</h2>
<p>Plants provide raw materials for the homes we live in, the food we eat and the oxygen we breathe. Without them, life as humans know it could not exist. </p>
<p>Nonetheless, many people think of plants more as a backdrop to life, rather than as a central part of it. Scientists and educators call this phenomenon <a href="https://doi.org/10.1002/ppp3.10153">plant awareness disparity</a> – a widespread cognitive bias that leads people to underestimate the diversity and importance of plants. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Light glistening off orange staghorn sumac leaves covered in morning dew." src="https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545167/original/file-20230829-26-f0vm7l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Staghorn sumac (<em>rhus typhina</em>) absorbing the last bits of nutrients from its dying leaves on a brisk fall morning as it prepares for winter dormancy.</span>
<span class="attribution"><span class="source">Let's Botanize, Inc.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
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<p>Research has shown the value of being outside in <a href="https://doi.org/10.1080/09638237.2020.1755027">natural green areas</a> or <a href="https://doi.org/10.1016/j.envres.2020.110420">around plants indoors</a>. Even traditional western doctors are starting to <a href="https://time.com/6171174/nature-stress-benefits-doctors/">prescribe nature walks</a> to reduce stress and improve physical well-being. Botanizing can provide a reason to get outdoors, and spending time closely observing plants’ minute structures is a great <a href="https://theconversation.com/mindfulness-meditation-and-self-compassion-a-clinical-psychologist-explains-how-these-science-backed-practices-can-improve-mental-health-198731">mindfulness practice</a>. </p>
<p>We also see botanizing as a valuable alternative to spending time on social media. As many experts have observed, online platforms have become so individually tailored by algorithms that each user participates in their own version of reality, a trend that has enabled increasingly <a href="https://doi.org/10.1007/s42001-020-00084-7">combative and antisocial behavior</a>. Botanizing is an opportunity to take a break from these tailored worlds and deeply engage with local human and nonhuman communities.</p>
<p>Finally, since plants form the foundation of life on Earth, caring for plants is a way of caring for our planet. Botanizing is one simple way to inspire change in other aspects of our lives that prioritizes sustainability. </p>
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<a href="https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Unfurling fiddlehead of the interrupted fern" src="https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545170/original/file-20230829-18-f0vm7l.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Ferns don’t produce flowers or fruits. Instead they reproduce by freely dispersing spores. Spores are produced in small structures called sporangia, which line the edges of the leaflets in this interrupted fern (<em>claytosmunda claytoniana</em>).</span>
<span class="attribution"><span class="source">Let's Botanize, Inc.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<h2>Tools of the trade</h2>
<p>There are many ways to botanize. Typically it involves trying to identify a plant species, observing its form and structure or assessing how it survives in the landscape. Plants are everywhere and don’t move, so this can be done in virtually any setting, including your windowsill or sidewalk.</p>
<p>So, how do you start? You can focus on plant structure, ecology, interactions, colors, textures or scents – or tastes, if you’re bold. You don’t need to travel far or spend a lot of money. There’s much to learn from your houseplants, <a href="https://theconversation.com/how-do-spices-get-their-flavor-202591">the food you cook</a>, the wood grain of your furniture, the plants growing in your sidewalks, gardens or local green spaces. </p>
<p>Here are a few essential tools: </p>
<p>– A <a href="https://www.nhbs.com/blog/the-nhbs-guide-to-hand-lenses">hand lens</a> is a window into the minutia of the botanical world. It’s as essential for a botanist as binoculars are for a birder. We recommend one with 10x magnification – that is, one that magnifies what you’re looking at by a factor of 10.</p>
<p>– A local field guide is your reference textbook. A good field guide to your local plants will have images and detailed text that you can use to cross-reference your identifications. </p>
<p>– A plant identification app can help confirm your identifications. Machine learning algorithms are getting increasingly good at matching plant images with species. One popular choice is <a href="https://play.google.com/store/apps/details?id=org.inaturalist.seek&hl=en&gl=US">the Seek app</a>, which is <a href="https://www.inaturalist.org/pages/what+is+it">powered by iNaturalist</a>, an online social network where people share information about living species and get help with identifications.</p>
<p>– Almost every region of the U.S. has local botanical clubs that typically hold regular meetings and organize workshops, online groups, botanizing days and more. Joining one is a great way to meet and learn from people with similar interests. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Light passing through a white flower with red stamens." src="https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545176/original/file-20230829-21-lde0bw.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Flowers like this magnolia (<em>magnolia sieboldii</em>) have evolved to entice insects and other pollinators visually. The magnolia’s blood-red stamens produce pollen, and its cream-colored column of fused carpels produces seeds.</span>
<span class="attribution"><span class="source">Let's Botanize, Inc.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>To germinate your initial interest, we recommend searching for a spark plant – one that excites, engages or is meaningful to you. It can be a plant that you are familiar with but haven’t seen growing in real life, one that is totally new to you, or one that you associate with a special moment. </p>
<p>If botanizing is to reclaim its place as a nature-based hobby, we believe it is important to reimagine it as a critically evolved 21st century pastime. That means looking at plants with appreciation – not simply as products for human use but as foundational and interconnected members of life on Earth.</p><img src="https://counter.theconversation.com/content/210616/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jacob S. Suissa is co-founder of the educational not-for-profit Let's Botanize, Inc.</span></em></p><p class="fine-print"><em><span>Ben Goulet-Scott is co-founder of the educational not-for-profit Let's Botanize, Inc. </span></em></p>Botanizing is the practice of observing and appreciating plant life. Two plant scientists explain how it benefits people and the planet.Jacob S. Suissa, Assistant Professor of Plant Evolutionary Biology, University of TennesseeBen Goulet-Scott, Higher Education & Laboratory Coordinator at Harvard Forest, Harvard UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2028332023-03-30T20:23:37Z2023-03-30T20:23:37ZAttention plant killers: new research shows your plants could be silently screaming at you<figure><img src="https://images.theconversation.com/files/518348/original/file-20230330-17-mdwwxo.jpeg?ixlib=rb-1.1.0&rect=0%2C23%2C3087%2C2152&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>If you’re like me, you’ve managed to kill even the hardiest of indoor plants (yes, despite a doctorate in plant biology). But imagine a world where your plants actually told you exactly when they needed watering. This thought, as it turns out, may not be so silly after all.</p>
<p>You might be familiar with the growing body of work that <a href="https://theconversation.com/heard-it-on-the-grapevine-the-mysterious-chatter-of-plants-6292">provides evidence for</a> plants being able to sense sounds around them. Now, new research suggests they can also generate airborne sounds in response to stress (such as from drought, or being cut).</p>
<p>A team led by experts at Tel Aviv University has shown tomato and tobacco plants, among others, not only make sounds, but do so loudly enough for other creatures to hear. Their findings, <a href="https://www.cell.com/cell/fulltext/S0092-8674(23)00262-3">published today</a> in the journal Cell, are helping us tune into the rich acoustic world of plants – one that plays out all round us, yet never quite within human earshot.</p>
<h2>Plants can listen, but now they can talk!</h2>
<p>Plants are “sessile” organisms. They can’t run away from stressors such as herbivores or drought. </p>
<p>Instead, they’ve evolved complex biochemical responses and the ability to dynamically alter their growth (and regrow body parts) in response to environmental signals including light, gravity, temperature, touch, and volatile chemicals produced by surrounding organisms.</p>
<p>These signals help them maximise their growth and reproductive success, prepare for and resist stress, and form mutually beneficial relationships with other organisms such as fungi and bacteria. </p>
<p>In 2019, <a href="https://www.nationalgeographic.com/science/article/flowers-can-hear-bees-and-make-their-nectar-sweeter">researchers showed</a> the buzzing of bees can cause plants to produce sweeter nectar. Others <a href="https://www.tandfonline.com/doi/full/10.1080/15592324.2017.1368938">have shown</a> white noise played to <em>Arabidopsis</em>, a flowering plant in the mustard family, can trigger a drought response.</p>
<p>Now, a team led by Lilach Hadany, who also led the aforementioned bee-nectar study, has recorded airborne sounds produced by tomato and tobacco plants, and five other species (grapevine, henbit deadnettle, pincushion cactus, maize and wheat). These sounds were ultrasonic, in the range of 20-100 kilohertz, and therefore can’t be detected <a href="https://www.ncbi.nlm.nih.gov/books/NBK10924/">by human ears</a>.</p>
<h2>Stressed plants chatter more</h2>
<p>To carry out their research, the team placed microphones 10cm from plant stems that were either exposed to drought (less than 5% soil moisture) or had been severed near the soil. They then compared the recorded sounds to those of unstressed plants, as well as empty pots, and found stressed plants emitted significantly more sounds than unstressed plants.</p>
<p>In a cool addition to their paper, they also included a soundbite of a recording, downsampled to an audible range and sped up. The result is a distinguishable “pop” sound.</p>
<p><audio preload="metadata" controls="controls" data-duration="36" data-image="" data-title="Plant sounds" data-size="289227" data-source="Khait et al" data-source-url="" data-license="CC BY-SA" data-license-url="http://creativecommons.org/licenses/by-sa/4.0/">
<source src="https://cdn.theconversation.com/audio/2774/plant-sounds-credit-khait-et-al.mp3" type="audio/mpeg">
</audio>
<div class="audio-player-caption">
Plant sounds.
<span class="attribution"><span class="source">Khait et al</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a><span class="download"><span>282 KB</span> <a target="_blank" href="https://cdn.theconversation.com/audio/2774/plant-sounds-credit-khait-et-al.mp3">(download)</a></span></span>
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<p>The number of pops increased as drought stress increased (before starting to decline as the plant dried up). Moreover, the sounds could be detected from a distance of 3-5 metres – suggesting potential for long-range communication.</p>
<h2>But what actually causes these sounds?</h2>
<p>While this remains unconfirmed, the team’s findings suggest that “cavitation” may be at least partially responsible for the sounds. Cavitation is the process through which air bubbles expand and burst inside a plant’s water-conducting tissue, or “xylem”. This explanation makes sense if we consider that drought stress and cutting will both alter the water dynamics in a plant stem. </p>
<p>Regardless of the mechanism, it seems the sounds produced by stressed plants were informative. Using machine learning algorithms, the researchers could distinguish not only which species produced the sound, but also what type of stress it was suffering from. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A small succulent in a colourful striped pot sits on a wooden table, with a black table mic to the left." src="https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/518350/original/file-20230330-26-z702j0.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">We now have the first research evidence that plants can make airborne sounds, heard up to a few metres away.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>It remains to be seen whether and how these sound signals might be involved in plant-to-plant communication or plant-to-environment communication. </p>
<p>The research has so far failed to detect any sounds from the woody stems of woody species (which includes many tree species), although they could detect sounds from non-woody parts of a grapevine (a woody species). </p>
<h2>What could it mean for ecology, and us?</h2>
<p>It’s temping to speculate these airborne sounds could help plants communicate their stress more widely. Could this form of communication help plants, and perhaps wider ecosystems, adapt better to change?</p>
<p>Or perhaps the sounds are used by other organisms to detect a plant’s health status. Moths, for example, hear within the ultrasonic range and lay their eggs on leaves, as the researchers point out. </p>
<p>Then there’s the question of whether such findings could help with future food production. The <a href="https://www.agriculture.gov.au/sites/default/files/sitecollectiondocuments/abares/publications/Outlook2012FoodDemand2050.pdf">global demand</a> for food will only rise. Tailoring water use to target individual plants or sections of field making the most “noise” could help us more sustainably intensify production and minimise waste. </p>
<p>For me personally, if someone could give a microphone to my neglected veggie patch and have the notifications sent to my phone, that would be much appreciated! </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/rosemary-in-roundabouts-lemons-over-the-fence-how-to-go-urban-foraging-safely-respectfully-and-cleverly-167883">Rosemary in roundabouts, lemons over the fence: how to go urban foraging safely, respectfully and cleverly</a>
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</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/202833/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Alice Hayward receives funding from The Australian Research Council Linkage Scheme, and various industry partners. Her salary is paid by The Queensland Alliance for Agriculture and Food Innovation (a partnership between The University of Queensland and The Department of Agriculture and Fisheries, Queensland). In the past she has received funding from The Queensland Government, The Australian Government, The Chinese Academy of Sciences, UQ and Hort Innovation Australia. She is a member of Native Plants Queensland and The Australian Branch of International Association of Plant Biotechnology.</span></em></p>For the first time, researchers have shown plants making sounds that can be heard up to a few metres away – just not by human ears.Alice Hayward, Molecular Biologist, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1897942022-11-15T19:08:19Z2022-11-15T19:08:19ZHumans are going back to the Moon, and beyond – but how will we feed them?<figure><img src="https://images.theconversation.com/files/482438/original/file-20220902-25-fyqpfc.jpeg?ixlib=rb-1.1.0&rect=208%2C9%2C1707%2C1348&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://twitter.com/Astro_Megan/status/1454190385190907912/photo/2">NASA JSC/Meghan McArthur</a></span></figcaption></figure><p><a href="https://www.nasa.gov/artemis-1">NASA’s Artemis I</a> launch is a major step forward in humans going deeper and spending longer in space than ever before.</p>
<p>Future Artemis missions plan to take crew to the Moon and eventually Mars, which is likely to be a three-year round-trip.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1592302969390759936"}"></div></p>
<p>But what will the astronauts eat? There are only so many protein bars and vitamins one can tolerate and survive on for years on end.</p>
<p>Plants are the basis of life on Earth with their amazing ability to convert light, water and carbon dioxide (CO₂) into food, and are the logical solution to support humans in space.</p>
<h2>The challenges of a space garden</h2>
<p>Astronauts have already eaten space radish, chilli peppers and lettuce grown on the International Space Station, and having freshly grown veggies in microgravity can support health and wellbeing. But there are a number of challenges in growing a flourishing space garden.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1454190385190907912"}"></div></p>
<p>Space environments are CO₂-rich, lack soil microbes, have altered gravity, are exposed to potentially harmful solar radiation, and need to use recycled, high-salt water. For plants to thrive in space and offer the full range of nutrients for human health, they need a redesign. </p>
<p>After months of freeze-dried or prepackaged <a href="https://www.rmg.co.uk/stories/topics/what-do-astronauts-eat-space">space food</a>, imagine going to your space garden, picking a ripe juicy tomato and spicy chilli to add to your tacos. Adding fresh produce has been a good way to improve astronaut wellbeing, supply essential vitamins and minerals, and add variety and flavour, especially as low-gravity environments <a href="https://www.theatlantic.com/technology/archive/2013/03/does-food-taste-the-same-in-space/273927/">affect our taste and smell</a>.</p>
<p>A renewable source of fresh food is essential to future long-term space missions, to avoid astronauts experiencing “food fatigue”, malnutrition and weight loss. </p>
<figure class="align-center ">
<img alt="A man looking at bright red chilies growing in a rectangular opening in the wall of a space capsule" src="https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482342/original/file-20220901-14-vky5ah.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chilies have been successfully grown on the ISS, and astronauts have consumed some of them in tacos.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasa2explore/51730013558">NASA Johnson</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Space plants are currently grown in closed boxes with low energy LED lights, porous clay “soil” with water, nutrients and oxygen supplied to roots; high-tech sensors and cameras monitor plant health. Plants did not evolve to grow in a box and use energy and resources in readiness for changes in light, temperature and disease, limiting full growth potential. </p>
<p>So there is great opportunity to adapt plant genetics to produce faster-growing “pick and eat” food crops such as tomato, carrot, spinach and strawberry designed to reach their maximum potential in closed, controlled environments. </p>
<figure class="align-center ">
<img alt="A black tray of small green leafy plants laid out in a grid" src="https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482346/original/file-20220901-15-juw7pn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Astronauts have also successfully grown radishes on the ISS, providing further data on space gardening experiments.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nasa2explore/50618080052">NASA Johnson</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<h2>A sustainable space plant future</h2>
<p>Future plant growth systems for space will need to be entirely sustainable. That means working alongside all the other systems on a space station or a lunar/Martian base, recycling water and nutrients.</p>
<p>All plant parts will need to be food, compost or converted into useful products such as fuels and plastics. Human waste, including urine, offers a nutrient source for plants, yet they also need to be able to cope with this salty water supply. However, there’s one plant that could be particularly suited to the task.</p>
<p><a href="https://phys.org/news/2019-08-duckweed-world.html">Duckweed</a> may not be available at your local supermarket, but this very fast-growing plant could be in all space gardens thanks to its ability to thrive in recycled water and be zero waste, with the whole plant being eaten.</p>
<p>Duckweed doubles its weight in just two days, is harvested continually, and is high in protein, nutrients, antioxidants and vitamins. Only a few essential elements (such as vitamin B12/D) are missing that could make it a reliable base source for complete human nutrition.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/duckweed-is-an-incredible-radiation-fighting-astronaut-food-and-by-changing-how-it-is-grown-we-made-it-better-140535">Duckweed is an incredible, radiation-fighting astronaut food – and by changing how it is grown, we made it better</a>
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</em>
</p>
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<p>Recent technical advances in genome editing, gene regulation, and methods to analyse nutrients can be harnessed to adapt duckweed and other plants for optimal growth, minimal waste and complete nutrition.</p>
<p>New plants developed in this way can contain proteins perfectly balanced for human digestion and use, healthy plant oils for an energy boost, and soluble fibre for better gut and cardiovascular health.</p>
<figure class="align-center ">
<img alt="Specks of round green leaves on a dark background" src="https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/482647/original/file-20220905-17-c4qywy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Duckweed, a fast-growing aquatic plant, could be the next space ‘superfood’.</span>
<span class="attribution"><span class="source">Onushi/Shutterstock</span></span>
</figcaption>
</figure>
<p>Striving to explore space has brought us <a href="https://spinoff.nasa.gov">thousands of innovations we use in everyday life</a>. We can expect that inventions we come up with to support humans thriving in space will deliver multiple and essential sustainability benefits to Earth, <a href="https://doi.org/10.1016/j.copbio.2021.08.018">especially to on-demand supply of nutrition and biomaterials</a>. Experts across the globe are working together toward these dual goals, including plant biologists, engineers, food chemists, psychologists, sensory experts, nutritionists, ethicists, and legal experts. </p>
<p>A new frontier of human achievement is on the horizon – humans will soon not only be looking up to the night skies in wonder, but also travelling to those destinations beyond our own atmosphere, and in so doing planting seeds of a new way of life on Earth and beyond.</p><img src="https://counter.theconversation.com/content/189794/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kim Johnson works for La Trobe University who are conducting work on growing plants in controlled environments. She collaborates with the Victorian Space Science Education Centre and investigator in the ARC Centre of Excellence in Plants for Space.</span></em></p><p class="fine-print"><em><span>Harvey Millar works for the University of Western Australia (UWA) conducting research on plant protein composition and modification of plants to suit environments. He is on the Board of the International Space Centre (ISC) at UWA and co-leads its Plants in Space research node. He receives funding from the Australian Research Council and is an investigator in the ARC Centre of Excellence in Plants for Space.</span></em></p><p class="fine-print"><em><span>Matthew Gilliham works for the University of Adelaide (UoA) who are conducting research into the use of plants to support of space exploration. He is Sustainability Lead for the Andy Thomas Centre for Space Resources at UoA and is on the Technical Advisory Group for Applied Space Medicine and Life Sciences at the Australian Space Agency. He is director of the ARC Centre of Excellence in Plants for Space. </span></em></p>The days of freeze-fried astronaut ice cream are long behind us. What will humans eat on Moon colonies in the future? Carefully engineered space gardens could be the answer.Kim Johnson, Senior lecturer, La Trobe UniversityHarvey Millar, Professor and ARC Australian Laureate Fellow, The University of Western AustraliaMatthew Gilliham, Professor in Plant Molecular Physiology, University of AdelaideLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1874602022-07-26T04:40:05Z2022-07-26T04:40:05ZI spent a year squeezing leaves to measure their water content. Here’s what I learned<figure><img src="https://images.theconversation.com/files/475758/original/file-20220724-30560-l0ixqx.JPG?ixlib=rb-1.1.0&rect=0%2C0%2C4000%2C3000&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Tomás I. Fuenzalida</span>, <span class="license">Author provided</span></span></figcaption></figure><p>How do you tell if your plants need water? Recently, I asked this question of a group of about 40 biologists at the Australian National University. </p>
<p>Most of them said they would stick their fingers into the soil. If you want to be more scientific about it, most horticulturalists would argue it is best to weigh the pot to determine how much water it contains.</p>
<p>I took a different view. After building special tools to <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/pce.14383">measure the “pulse” of plants</a>, I am more inclined to feel the leaves.</p>
<p>Not only can touch provide a new way to follow the flow of water through plant cells, it may also deliver new possibilities for plant monitoring and care. </p>
<h2>The rhythm of plants</h2>
<p>Plants have a natural rhythm, like a very slow heartbeat, caused by changing water pressure inside their cells. </p>
<p>Plants only beat around once a day, dehydrating during the day and rehydrating during the night. This process is too slow to watch for all but the most patient observers.</p>
<p>The pressure inside plant cells is called “turgor” and is usually between five and 20 atmospheres (up to 10 times the pressure inside a car tyre!). But while this pressure is large, plant cells are only a fraction of a millimetre in size. </p>
<p>For this reason, measuring turgor pressure has been traditionally been difficult and only done in lab settings. Put simply, we do not have a plug-and-play method to monitor the beating of plants.</p>
<h2>Squeezing leaves</h2>
<p>Measuring plant water status is pretty important. On a global scale, <a href="https://www.nature.com/articles/nature11983">more water flows through plants than through rivers</a>, and a great part of this flux is regulated by changes in leaf turgor pressure. </p>
<p>Similarly, <a href="https://unesdoc.unesco.org/ark:/48223/pf0000375737">agriculture uses about 70% of all the water managed by humans</a>, and <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev-arplant-102820-012804">many forests around the world are succumbing to drought</a>. It is a key time to study the beating of plants. But where to start?</p>
<p>While doing my PhD studying water movement in plants, I was trying to find a simple way to measure turgor pressure and water content. </p>
<p>Although turgor is a property of single cells, I thought I could monitor a group of cells by carefully squeezing a leaf. </p>
<p>My ideas were simple. Leaves are thicker when they contain more water, so I could monitor the water content by measuring the thickness of the leaf, which I would do by squeezing it with a constant amount of force.</p>
<p>And to monitor the water pressure inside a leaf’s cells, I could measure the force exerted by the leaf when constrained to a given thickness.</p>
<p>As it turned out, these two ideas were not new – only new to me, and perhaps new to plant science. Materials scientists use tests like these all the time: a constant-force test is called a creep experiment, while a constant-thickness test is called a stress relaxation experiment. </p>
<h2>How it works</h2>
<p>A year of tinkering and thinking about this problem allowed me to test my ideas in a very simple way. I bought a micrometer (a workshop tool used to measure distances very accurately), coupled it with a motor, a force sensor and some computer controls, and devoted myself to squeezing leaves. </p>
<p>Preliminary tests worked well, and then I couldn’t stop doing it! </p>
<p>Within the next six months, I had replaced the last chapter of my PhD with this serendipitous project. Colleagues and I successfully validated and <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/pce.14383">published</a> this simple method to monitor plant water status. </p>
<p>In the figure below, you can see the changes in the leaf thickness and turgidity of a grey mangrove (<em>Aviennia marina</em>) measured under changing light conditions.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=391&fit=crop&dpr=1 600w, https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=391&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=391&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/475748/original/file-20220724-30685-h5ea7j.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Monitoring the beating of plants is possible using a simple device that squeezes leaves with a constant force (green) or with a constant thickness (blue). The resulting thickness and pressure are related to water content and turgor pressure.</span>
</figcaption>
</figure>
<h2>Touching plants</h2>
<p>Measuring the beating of plants is important, but this is not the only exciting aspect of this project. </p>
<p>More broadly, touch-based measurements could uncover a new wealth of information about plant life. This venture may help us understand climate, save water, and hopefully help us in addressing “<a href="https://theconversation.com/botanists-are-disappearing-just-when-the-world-needs-them-most-186849">plant blindness</a>”. </p>
<p>Plants are very adaptable organisms. Much of their adaptability comes from the ability to modify their body plan to suit different conditions. </p>
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<p>
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Read more:
<a href="https://theconversation.com/botanists-are-disappearing-just-when-the-world-needs-them-most-186849">Botanists are disappearing – just when the world needs them most</a>
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</em>
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<p>Being modular organisms made up of a collection of different cells, plants often modify the structure of cells and tissues, the strength of their walls, and the concentration of water-retaining compounds inside the cells. All of these properties, like turgor, are difficult to measure.</p>
<p>Touch provides scientists with a simple tool to study these mechanical properties of plant tissues.</p>
<p>A simple robotic system that could stay on a tree and continuously “feel” how the properties of its leaves (and stems, fruits and roots) change over time would have vast applications in research and industry.</p><img src="https://counter.theconversation.com/content/187460/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tomás I. Fuenzalida does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Carefully squeezing plant leaves can reveal how much water they contain – and touch could reveal many other hard-to-measure properties of plants.Tomás I. Fuenzalida, Postdoctoral Fellow, Research School of Biology, Australian National UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1200512019-07-22T10:58:27Z2019-07-22T10:58:27ZMicro-naps for plants: Flicking the lights on and off can save energy without hurting indoor agriculture harvests<figure><img src="https://images.theconversation.com/files/284584/original/file-20190717-147270-19g06yc.jpg?ixlib=rb-1.1.0&rect=328%2C194%2C4277%2C3113&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pulses of light followed by extended dark periods might help make indoor agricultural production more sustainable.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/led-lighting-used-grow-lettuce-inside-1384001177?studio=1">DutchScenery/Shutterstock.com</a></span></figcaption></figure><p>A nighttime arrival at Amsterdam’s Schiphol Airport flies you over the bright pink glow of vegetable production greenhouses. Growing crops under artificial light is <a href="https://www.marketwatch.com/press-release/at-396-cagr-vertical-farming-and-plant-factory-market-size-projected-to-cross-usd-11000-million-by-2024-2019-02-21">gaining momentum</a>, particularly in regions where produce prices can be high during seasons when sunlight is sparse.</p>
<p><a href="https://www.wur.nl/en/Dossiers/file/Vertical-farming.htm">The Netherlands</a> is just one country that has rapidly adopted <a href="https://en.wikipedia.org/wiki/Controlled-environment_agriculture">controlled-environment agriculture</a>, where high-value specialty crops like herbs, fancy lettuces and tomatoes are produced in year-round illuminated greenhouses. <a href="http://www.verticalfarm.com/?page_id=36">Advocates suggest</a> these completely enclosed buildings – or <a href="https://urbanagnews.com/blog/japan-special-report-plant-factories-with-artificial-light-pfal/">plant factories</a> – could be a way to repurpose urban space, decrease food miles and provide local produce to city dwellers.</p>
<p>One of the central problems of this process is the <a href="https://theconversation.com/food-security-vertical-farming-sounds-fantastic-until-you-consider-its-energy-use-102657">high monetary cost of providing artificial light</a>, usually via a combination of red and blue light-emitting diodes. <a href="https://doi.org/10.2183/pjab.89.447">Energy costs</a> sometimes exceed 25% of the operational outlay. How can growers, particularly in the developing world, <a href="https://www.voanews.com/usa/people-power-costs-keep-indoor-farming-down-earth">compete when the sun is free</a>? Higher energy use also translates to more carbon emissions, rather than the decreased carbon footprint sustainably farmed plants can provide.</p>
<p>I’ve <a href="https://scholar.google.com/citations?user=kIh3BRwAAAAJ&hl=en&oi=ao">studied how light affects plant growth and development</a> for over 30 years. I recently found myself wondering: Rather than growing plants under a repeating cycle of one day of light and one night of darkness, what if the same daylight was split into pulses lasting only hours, minutes or seconds?</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/284583/original/file-20190717-147295-16meq90.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Indoor plants need plenty of artificial light.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/ventilator-special-led-lights-belts-above-1428413504?studio=1">josefkubes/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Short bursts of light and dark</h2>
<p>So my colleagues and I <a href="https://doi.org/10.1016/j.envexpbot.2019.103803">designed an experiment</a>. We’d apply the normal amount of light in total, just break it up over different chunks of time.</p>
<p>Of course plants depend on light for photosynthesis, the process that in nature uses the sun’s energy to merge carbon dioxide and water into sugars that fuel plant metabolism. Light also directs growth and development through its signals about day and night, and monkeying with that information stream might have disastrous results.</p>
<p>That’s because breaking something good into smaller bits sometimes creates new problems. Imagine how happy you’d be to receive a US$100 bill – but not as thrilled with the equivalent 10,000 pennies. We suspected a plant’s internal clock wouldn’t accept the same luminous currency when broken into smaller denominations.</p>
<p>And that’s exactly what we <a href="https://doi.org/10.1016/j.envexpbot.2019.103803">demonstrated in our experiments</a>. Kale, turnip or beet seedlings exposed to cycles of 12 hours of light, 12 hours dark for four days grew normally, accumulating pigments and growing larger. When we decreased the frequency of light-dark cycles to 6 hours, 3 hours, 1 hour or 30 minutes, the plants revolted. We delivered the same amount of light, just applied in different-sized chunks, and the seedlings did not appreciate the treatment. </p>
<p>The same amount of light applied in shorter intervals over the day caused plants to grow more like they were in darkness. We suspect the light pulses conflicted with a <a href="https://doi.org/10.1105/tpc.106.040980">plant’s internal clock</a>, and the seedlings had no idea what time of day it was. Stems stretched taller in an attempt to find more light, and processes like pigment production were put on hold.</p>
<p>But when we applied light in much, much shorter bursts, something remarkable happened. Plants grown under five-second on/off cycles appeared to be almost identical to those grown under the normal light/dark period. It’s almost like the internal clock can’t get started properly when sunrise comes every five seconds, so the plants don’t seem to mind a day that is a few seconds long.</p>
<p>Just as we prepared to publish, undergraduate collaborator Paul Kusuma found that our discovery was not so novel. We soon realized we’d actually rediscovered something already known for 88 years. Scientists at the U.S. Department of Agriculture <a href="https://naldc.nal.usda.gov/download/IND43968018/PDF">saw this same phenomenon in 1931</a> when they grew plants under light pulses of various durations. Their work in mature plants matches what we observed in seedlings with remarkable similarity.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=565&fit=crop&dpr=1 754w, https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=565&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/285200/original/file-20190722-11339-185bjd3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=565&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A 1931 study by Garner and Allard tracked the growth of Yellow Cosmos flowers under light pulses of various durations.</span>
<span class="attribution"><span class="source">J. Agri. Res. 42: National Agricultural Library, Agricultural Research Service, U.S. Department of Agriculture.</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Not only was all of this a retread of an old idea, but pulses of light do not save any energy. Five seconds on and off uses the same amount of energy as the lights being on for 12 hours; the lights are still on for half the day. </p>
<p>But what would happen if we extended the dark period? Five seconds on. Six seconds off. Or 10 seconds off. Or 20 seconds off. Maybe 80 seconds off? They didn’t try that in 1931.</p>
<h2>Building in extra downtime</h2>
<p>It turns out that the plants don’t mind a little downtime. After applying light for five seconds to activate photosynthesis and biological processes like pigment accumulation, we turned the light off for 10, or sometimes 20 seconds. Under these extended dark periods, the seedlings grew just as well as they had when the light and dark periods were equal. If this could be done on the scale of an indoor farm, it might translate to a significant energy savings, at least 30% and maybe more.</p>
<p>Recent yet-to-be published work in our lab has shown that the same concept works in leaf lettuces; they also don’t mind an extended dark time between pulses. In some cases, the lettuces are green instead of purple and have larger leaves. That means a grower can produce a diversity of products, and with higher marketable product weight, by turning the lights off.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=350&fit=crop&dpr=1 600w, https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=350&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=350&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=440&fit=crop&dpr=1 754w, https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=440&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/284079/original/file-20190715-173342-1fvujyt.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=440&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">One variety of lettuce grew purple when given a 10-second dark period. They look similar to those grown with a five-second dark period, yet use 33% less energy. Extending the dark period to 20 seconds yielded green plants with more biomass.</span>
<span class="attribution"><span class="source">J. Feng, K. Folta</span></span>
</figcaption>
</figure>
<p>Learning that plants can be grown under bursts of light rather than continuous illumination provides a way to potentially trim the expensive energy budget of indoor agriculture. More fresh vegetables could be grown with less energy, making the process more sustainable. My colleagues and I think this innovation could ultimately help drive new business and feed more people – and do so with less environmental impact.</p>
<hr>
<p><em>This article was updated with a corrected legend on the photograph of the plants grown in 1931.</em></p><img src="https://counter.theconversation.com/content/120051/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kevin M. Folta received funding from the United States Department of Agriculture National Institute of Food and Agriculture and Vindara Inc to work on questions in agricultural lighting. He is affiliated with Eggsotics Eggs and Produce where his family grows some direct-market produce under hydroponic and/or artificial light conditions. He is reimbursed for travel related to talks in research and science communication. A full list of prior research funding may be seen at <a href="http://www.kevinfolta.com/transparency">www.kevinfolta.com/transparency</a></span></em></p>Indoor plant factories have high energy costs since LEDs replace the sunlight outdoor plants get for free. Scientists found a way to dial back how much light is needed by breaking it into tiny bursts.Kevin M. Folta, Professor of Horticultural Sciences and Plant Molecular and Cellular Biology, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1030262018-09-19T14:39:50Z2018-09-19T14:39:50Z‘Plant blindness’ is a real thing: why it’s a real problem too<figure><img src="https://images.theconversation.com/files/235801/original/file-20180911-144470-5y5zoz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">South African Tourism/Flickr</span></span></figcaption></figure><p>If you lived in London at the height of William Shakespeare’s fame, in the 15th century, you probably knew <a href="https://pubag.nal.usda.gov/catalog/63038">a fair amount about plants</a>. The famous playwright often alluded to potions and poisons derived from plants, and most of his audience would have recognised them. By comparison, <a href="https://pubag.nal.usda.gov/catalog/63038">research has shown</a> that most modern Londoners can’t name more than a few wild flowers.</p>
<p>This is true of most people in most cities in the world.</p>
<p>There’s a name for this inability to notice or recognise plants in one’s own environment: “<a href="https://onlinelibrary.wiley.com/doi/full/10.1111/cobi.12738">plant blindness</a>”. Part of the reason for this is that urban dwellers have been separated from nature; there’s a disconnect between us and the environment, and we’re blind to the natural world around us.</p>
<p>Two botanists, <a href="https://www.jstor.org/stable/4450624?seq=1#metadata_info_tab_contents">James Wandersee</a> and <a href="https://botany.org/PlantScienceBulletin/psb-2001-47-1.php">Elisabeth Schussler</a>, have proposed that our inability to see and notice plants is because they lack visual attention cues. They don’t have a face; they don’t move in the way that animals do; and they aren’t threatening. Our eye-brain system and the visual cortex filter out so much “data” from what we see daily that most of the visual information about the plants we see is discarded. </p>
<p>Humans have also placed themselves <a href="https://books.google.co.za/books?hl=en&lr=&id=5fc7AQAAQBAJ&oi=fnd&pg=PP1&dq=Plants+as+Persons:+A+Philosophical+Botany&ots=JpC_zGAY1r&sig=goVFvkfQQ2gD1hKDIPXZymFAG-k#v=onepage&q=Plants%20as%20Persons%3A%20A%20Philosophical%20Botany&f=false">above</a> animals and plants <a href="https://takku.net/mediagallery/mediaobjects/orig/f/f_val-plumwood-feminism-and-the-mastery-of-nature-pdf.pdf">for centuries</a>.</p>
<p>So why is plant blindness a problem? Many of our biggest challenges of the 21st century are plant based: global warming, food security and the need for new pharmaceuticals that might help in the fight against diseases. Without a basic knowledge of plant structure, function and diversity, there’s little hope of addressing these problems. </p>
<p>Another issue is that children who are not taught about plants have an incomplete knowledge of the world around them. They grow into adults who don’t care about the environment and the natural resources we rely on every day. The lack of in-depth plant sciences education in schools perpetuates the problem, as students do not know that there are various careers in the plant sciences. </p>
<p>Without well trained scientists, many potential threats such as the effects of global warming and devastating plant diseases could be missed. </p>
<h2>How plant blindness happens</h2>
<p>Plant blindness begins in childhood, exacerbated by how little attention is paid to botanical content in school. For example, in South Africa only <a href="https://www.sajs.co.za/article/view/4146/6193">about 11 hours</a> are devoted to plant related content in the foundation phase at school (grade R-3). In the senior phases (grade 7-9) <a href="https://www.sajs.co.za/article/view/4146/6193">only 11 hours</a> are devoted to content that’s specifically focused on plants. </p>
<p>This lack of botanical content is echoed in school curricula <a href="http://abt.ucpress.edu/content/58/6/34.full.pdf+html">worldwide</a>. In the US, school science textbooks devote only <a href="https://www.jstor.org/stable/4449818">between 14 and 20%</a> of their content to plants. This hampers a positive attitude towards plants and the development of a relationship with the environment. It does not inspire pupils to want to know more about plants or to care for their environment.</p>
<p>The problem extends into higher education. The number of students studying botany and plant sciences at universities has declined so much that universities across the US are <a href="https://phys.org/news/2015-05-students-botany.html">shutting their herbaria</a>. In the United Kingdom, you can <a href="https://www.tandfonline.com/doi/pdf/10.3108/beej.17.2">no longer enrol</a> for a Botany degree.</p>
<p>Statistics about the standing of botany or plant sciences education in South Africa and elsewhere in Africa aren’t readily available. However, the advancing age of practising botanists together with an inadequate of training of young botanists is a <a href="http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S0038-23532008000200002">source of concern</a>. This leaves a worrying gap – for example when it comes to things like crop diseases.</p>
<p>Scientists are a first line of defence against these and can play a key role in managing any threat. For example, in 1971 a fungal infection decimated most of the US’s corn crops. Plant scientists were able to <a href="https://www.youtube.com/watch?v=sUzrRo1T274">identify the problem</a> and take steps to mitigate it, avoiding a major disaster. </p>
<p>Plant scientists also contribute to food security on many different levels. Medical or ethnobotanists are involved in the discovery of new drugs.</p>
<h2>Possible solutions</h2>
<p>So can plant blindness be solved? The <a href="https://www.jstor.org/stable/4450624?seq=1#metadata_info_tab_contents">general consensus</a> among researchers is “yes” – but it will not be easy.</p>
<p>For starters, countries must prioritise scientific and social education about plants among children. But, since <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/cobi.12738">psychological studies</a> have shown that education alone is typically not enough to alter behaviour, it’s important for kids also so get hands on with plants. Direct experiences allow people to connect with plants on a cognitive and emotional level. For example, parents can encourage their children to plant some vegetables and then cook dinner from the harvest.</p>
<p>There are also many botanical gardens around the world with sections <a href="https://www.researchgate.net/publication/235862296_Opening_the_window_on_'plant-blindness'">especially designed to foster interests in plants</a>. If there’s one in your city, go and visit – it’s a great way to open your eyes to the existence and value of plants.</p>
<p>Governments have a role to play, too. South Africa’s Department of Science and Technology has placed a large emphasis on plants in growing <a href="https://mg.co.za/article/2014-01-14-science-department-launches-sas-bio-economy-strategy">its bio-economy strategy</a>. </p>
<p>In broad terms, this involves using activities such as agriculture and biotechnology to generate economic output. But for this to work, the government needs well trained scientists who can work in the relevant different sectors. </p>
<p>The government must work to develop existing plant scientists, and put in place incentives to draw new people to the field. Funding, access to next-generation technologies and good communication strategies that show the importance of plant sciences would all be useful approaches.</p><img src="https://counter.theconversation.com/content/103026/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Angelique Kritzinger does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Plant blindness can be solved but it wont be easy.Angelique Kritzinger, Lecturer, Department of Plant and Soil Sciences. Specializing in Education, University of PretoriaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/818032017-09-15T10:21:37Z2017-09-15T10:21:37ZSeeds in space – how well can they survive harsh, non-Earth conditions?<figure><img src="https://images.theconversation.com/files/185909/original/file-20170913-18075-165yqah.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Spend many months attached to the ISS and see how well you grow.</span> <span class="attribution"><a class="source" href="https://www.nasa.gov/mission_pages/station/research/experiments/1674.html">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Will we someday colonize space? Will our children visit other planets? To achieve goals like these, we’ll need to crack one crucial challenge: how to feed ourselves for long periods away from Earth.</p>
<p>A <a href="http://www.mars-one.com/faq/mission-to-mars/how-long-does-it-take-to-travel-to-mars">trip to Mars would take months</a>, and exploring the depths of the galaxy would take even longer. Provision of nutritious food for travelers is a significant obstacle. While stockpiling food is an option, storing enough to last many months strains weight and space limitations in spacecraft – and missions could easily outlast food shelf life. Growing food in space will be essential.</p>
<p>Essential – and not necessarily easy. The conditions in the vacuum of space are quite harsh compared to Earth. Seeds in space must be able to withstand large doses of ultraviolet and cosmic radiation, low pressure and microgravity. </p>
<p>Believe it or not, the first space travelers were seeds. In 1946, <a href="https://www.nasa.gov/pdf/449089main_White_Sands_Missile_Range_Fact_Sheet.pdf">NASA launched a V-2 rocket carrying maize</a> seeds to observe how they’d be affected by radiation. Since then, the scientific community has learned <a href="https://doi.org/10.1079/SSR200193">a great deal</a> about the effects of the space environment on seed <a href="https://doi.org/10.1016/j.asr.2011.05.017">germination</a>, <a href="https://doi.org/10.1016/0273-1177(86)90076-1">metabolism</a>, <a href="https://doi.org/10.1016/j.asr.2005.06.043">genetics</a>, <a href="http://journal.ashspublications.org/content/130/6/848.short">biochemistry</a> and even <a href="https://doi.org/10.1016/S0273-1177(03)00250-3">seed</a> <a href="https://doi.org/10.1016/j.actaastro.2006.09.009">production</a>. </p>
<p>Astrobiologists David Tepfer and Sydney Leach recently investigated <a href="https://doi.org/10.1089/ast.2015.1457">how seeds would do back on Earth</a> after spending extended periods on the International Space Station. The experiments they conducted on the <a href="https://www.nasa.gov/mission_pages/station/research/experiments/696.html">EXPOSE</a> <a href="https://www.nasa.gov/mission_pages/station/research/experiments/211.html">missions</a> were much longer than many other ISS seed experiments, and placed the seeds on the outside of the station, in the dead of space, rather than inside. The goal was to understand not only the effects of long-term radiation exposure, but a bit about the molecular mechanisms of those effects.</p>
<h2>Seeds have some defenses</h2>
<p>Seeds possess a couple of remarkable traits that Tepfer and Leach hypothesized would give these “model space travelers” a fighting chance.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=575&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=575&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=575&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=722&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=722&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185911/original/file-20170913-20280-41e1zd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=722&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Seeds protect their important insides with a strong external seed coat.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Dycotyledon_seed_diagram-en.svg">LadyofHats</a></span>
</figcaption>
</figure>
<p>First, they contain multiple copies of important genes – what scientists call redundancy. Genetic redundancy is common in flowering plants, especially food products such as <a href="https://www.sciencedaily.com/releases/2014/09/140930090636.htm">seedless watermelon and strawberries</a>. If one genetic copy is damaged, there’s still another available to do the job.</p>
<p>Secondly, seed coats contain chemicals called flavonoids that act as sunscreens, protecting the seed’s DNA from damage by ultraviolet (UV) light. On Earth, our planet’s atmosphere filters out some harmful UV light before it can reach us. But in space, there is no protective atmosphere.</p>
<p>Would these special features be enough to let the seeds survive or even thrive? To find out, Tepfer and Leach conducted a series of experiments – both outside the International Space Station and back on Earth – with tobacco, <em>Arabidopsis</em> (a flowering plant commonly used in research) and morning glory seeds. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=440&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=440&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=440&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=553&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=553&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185905/original/file-20170913-20310-w6bmrn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=553&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The EXPOSE-R experiment attached to the exterior of the International Space Station.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/mission_pages/station/expeditions/expedition26/russian_eva27.html">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Bombarded with energy</h2>
<p>Their EXPOSE-E experiment flew to the International Space Station (ISS) in 2008 and lasted 558 days – so just under two years.</p>
<p>They stored the seeds in a single layer on the outside of the ISS behind a special kind of glass that let in ultraviolet radiation only at wavelengths between 110 and 400 nanometers. DNA readily absorbs UV radiation in this wavelength range. A second, identical set of seeds was on the ISS, but shielded completely from UV radiation. The purpose of this experimental design was to observe the effects of UV radiation separately from other types of radiation <a href="https://www.space.com/32644-cosmic-rays.html">like cosmic rays</a> that are everywhere in space.</p>
<p>Tepfer and Leach chose tobacco and <em>Arabidopsis</em> seeds for EXPOSE-E because both have a redundant genome and therefore good odds for survival. They also included a genetically engineered variety of tobacco with an antibiotic resistance gene added; the plan was to later test this gene in bacteria and determine if there was any damage. In addition to normal <em>Arapidopsis</em>, they sent up two genetically modified strains of the plant that contained low and absent UV-protective chemicals in their seed coat. They also sent purified DNA and purified flavonoids. This gave the researchers a wide range of scenarios by which to understand the effects of space on the seeds.</p>
<p>A second ISS mission called EXPOSE-R included only the three types of <em>Arabidopsis</em> seeds. These received a little over double the dose of ultraviolet light because of the longer experiment time, 682 days. Lastly, researchers performed a ground experiment back in the lab that exposed <em>Arabidopsis</em>, tobacco and morning glory seeds to very high doses of UV light for only a month.</p>
<p>After all these various exposure conditions, it was time to see how well the seeds could grow.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=410&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=410&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=410&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=515&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=515&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185907/original/file-20170913-20270-l4me1j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=515&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The Expose-R experiment was equipped with three trays containing a variety of biological samples – including seeds.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/mission_pages/station/multimedia/exp18_eva2.html">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>What would researchers reap?</h2>
<p><a href="https://doi.org/10.1089/ast.2015.1457">When the seeds returned to Earth</a>, the researchers measured their germination rates – that is, how quickly the root emerged from the seed coat.</p>
<p>The seeds that had been shielded in the lab did the best, with more than 90 percent of them germinating. Next came the seeds that had been exposed to UV radiation for one month in the laboratory, with better than 80 percent germinating. </p>
<p>For the space-traveling seeds, more than 60 percent of the shielded seeds germinated. A mere 3 percent of space UV-exposed seeds did.</p>
<p>The 11 <em>Arabidopsis</em> plants that did grow from both the wild type and genetically engineered seeds did not survive once planted in soil. Tobacco plants, however, showed reduced growth but that growth rate recovered in subsequent generations. Tobacco has a much heartier seed coat and a more redundant genome, which may explain its apparent survival advantage.</p>
<p>When the researchers plugged the antibiotic resistance gene into bacteria, they found it was still functional after its trip to space. That finding suggests it’s not genetic damage that’s making these seeds less viable. Tepfer and Leach attributed the reduced germination rate to damage to other molecules in the seed besides DNA – such as proteins. A redundant genome or built-in DNA repair mechanisms weren’t going to overcome that damage, further explaining why the <em>Arabidopsis</em> plants didn’t survive transplanting.</p>
<p>In the ground experiments, the researchers found that radiation damage is dose-dependent – the more radiation the seeds received, the worse their germination rate.</p>
<p>These discoveries could inform future directions for research in space agriculture. Scientists may consider genetically engineering seeds to have added protection for the cellular machinery critical for protein synthesis, such as ribosomes. Future research will also need to explore further how seeds stored in space germinate in microgravity, rather than on Earth.</p>
<p>As researchers add to the knowledge of how space affects plants and their seeds, we can continue to make the strides necessary toward producing food in space. It will be a crucial step toward sustainable colonies that can survive beyond the comfortable confines of Earth’s biosphere.</p><img src="https://counter.theconversation.com/content/81803/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Gina Riggio is affiliated with Blue Marble Space.</span></em></p>If you want to live on Mars, you’re going to need to grow food. Seeds are naturally equipped to handle challenging Earth environments, but how well can they survive what they’ll encounter off-planet?Gina Misra, Ph.D. Student in Cell and Molecular Biology, University of ArkansasLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/794272017-07-24T09:18:41Z2017-07-24T09:18:41ZRising carbon dioxide is making the world’s plants more water-wise<p>Land plants are absorbing 17% more carbon dioxide from the atmosphere now than 30 years ago, our <a href="https://www.nature.com/articles/s41467-017-00114-5">research published today</a> shows. Equally extraordinarily, our study also shows that the vegetation is hardly using any extra water to do it, suggesting that global change is causing the world’s plants to grow in a more water-efficient way. </p>
<p>Water is the most precious resource needed for plants to grow, and our research suggests that vegetation is becoming much better at using it in a world in which CO₂ levels <a href="https://theconversation.com/global-stocktake-shows-the-43-greenhouse-gases-driving-global-warming-77796">continue to rise</a>. </p>
<p>The ratio of carbon uptake to water loss by ecosystems is what we call “water use efficiency”, and it is one of the most important variables when studying these ecosystems.</p>
<p>Our confirmation of a global trend of increasing water use efficiency is a rare piece of good news when it comes to the consequences of global environmental change. It will strengthen plants’ vital role as global carbon sinks, improve food production, and might boost water availability for the well-being of society and the natural world. </p>
<p>Yet more efficient water use by the world’s plants will not solve our current or future water scarcity problems. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=240&fit=crop&dpr=1 600w, https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=240&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=240&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=302&fit=crop&dpr=1 754w, https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=302&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/174634/original/file-20170620-22092-g9flkd.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=302&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Changes in global terrestrial uptake of carbon dioxide, water use efficiency and ecosystem evapotranspiration during 1982-2011.</span>
</figcaption>
</figure>
<h2>Boosting carbon uptake</h2>
<p>Plants growing in today’s higher-CO₂ conditions can take up more carbon – the so-called CO₂ fertilisation effect. This is the main reason why the terrestrial biosphere has taken up 17% more carbon over the past 30 years. </p>
<p>The enhanced carbon uptake is consistent with the <a href="https://theconversation.com/rising-carbon-dioxide-is-greening-the-earth-but-its-not-all-good-news-58282">global greening trend</a> observed by satellites, and the growing global land carbon sink which <a href="http://www.globalcarbonproject.org/carbonbudget/index.htm">removes about one-third</a> of all CO₂ emissions generated by human activities.</p>
<p>Increasing carbon uptake typically comes at a cost. To let CO₂ in, plants have to open up pores called stomata in their leaves, which in turn allows water to sneak out. Plants thus need to strike a balance between taking up carbon to build new leaves, stems and roots, while minimising water loss in the process. This has led to sophisticated adaptations that has allowed many plant species to conquer a range of arid environments. </p>
<p>One such adaptation is to close the stomata slightly to allow CO₂ to enter with less water getting out. Under increasing atmospheric CO₂, the overall result is that CO₂ uptake increases while water consumption does not. This is exactly what we have found on a global scale in our new study. In fact, we found that rising CO₂ levels are causing the world’s plants to become more water-wise, almost everywhere, whether in dry places or wet ones. </p>
<h2>Growth hotspots</h2>
<p>We used a combination of plot-scale water flux and atmospheric measurements, and satellite observations of leaf properties, to develop and test a new water use efficiency model. The model enables us to scale up from leaf water use efficiency anywhere in the world to the entire globe.</p>
<p>We found that across the globe, boreal and tropical forests are particularly good at increasing ecosystem water use efficiency and uptake of CO₂. That is due in large part to the CO₂ fertilisation effect and the increase in the total amount of leaf surface area. </p>
<p>Importantly, both types of forests are critical in limiting the rise in atmospheric CO₂ levels. Intact tropical forest <a href="http://science.sciencemag.org/content/333/6045/988">removes more atmospheric CO₂</a> than any other type of forest, and the boreal forests of the planet’s far north hold <a href="http://onlinelibrary.wiley.com/doi/10.1029/2008GB003327/abstract">vast amounts of carbon</a> particularly in their organic soils.</p>
<p>Meanwhile, for the semi-arid ecosystems of the world, increased water savings are a big deal. We found that Australian ecosystems, for example, are increasing their carbon uptake, especially in the <a href="https://theconversation.com/ecocheck-australias-vast-majestic-northern-savannas-need-more-care-59897">northern savannas</a>. This trend may not have been possible without an increase in ecosystem water use efficiency. </p>
<p>Previous studies have also shown how increased water efficiency is <a href="http://onlinelibrary.wiley.com/doi/10.1002/grl.50563/abstract">greening semi-arid regions</a> and may have contributed to an <a href="http://www.nature.com/nature/journal/v509/n7502/full/nature13376.html">increase in carbon capture</a> in semi-arid ecosystems in Australia, Africa and South America.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=343&fit=crop&dpr=1 600w, https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=343&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=343&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=430&fit=crop&dpr=1 754w, https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=430&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/176169/original/file-20170629-3154-1xr77xx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=430&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Trends in water use efficiency over 1982-2011.</span>
<span class="attribution"><span class="source">CREDIT</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<h2>It’s not all good news</h2>
<p>These trends will have largely positive outcomes for the plants and the animals (and humans) consuming them. Wood production, bioenergy and crop growth are (and will be) less water-intensive under climate change than they would be without increased vegetation water use efficiency.</p>
<p>But despite these trends, water scarcity will nevertheless continue to constrain carbon sinks, food production and socioeconomic development. </p>
<p>Some studies have suggested that the water savings could also lead to <a href="http://www.nature.com/nature/journal/v448/n7157/edsumm/e070830-08.html">increased runoff</a> and therefore excess water availability. For dry Australia, however, <a href="http://www.biogeosciences.net/10/2011/2013/">more than half (64%)</a> of the rainfall returning to the atmosphere does not go through vegetation, but through direct soil evaporation. This reduces the potential benefit from increased vegetation water use efficiency and the possibility for more water flowing to rivers and reservoirs. In fact, a <a href="http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_19-10-2015-14-49-2">recent study</a> shows that while semi-arid regions in Australia are greening, they are also consuming more water, causing river flows to fall by 24-28%. </p>
<p>Our research confirms that plants all over the world are likely to benefit from these increased water savings. However, the question of whether this will translate to more water availability for conservation or for human consumption is much less clear, and will probably vary widely from region to region.</p><img src="https://counter.theconversation.com/content/79427/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pep Canadell receives funding from the Australian National Environmental Science Program.</span></em></p><p class="fine-print"><em><span>Francis Chiew works for CSIRO, which receives funding from the Commonwealth Government. </span></em></p><p class="fine-print"><em><span>Lei Cheng works for CSIRO, which receives funding from the Commonwealth Government.</span></em></p><p class="fine-print"><em><span>Lu Zhang works for CSIRO, which receives funding from the Commonwealth Government. </span></em></p><p class="fine-print"><em><span>Ying-Ping Wang receives funding from the Australian National Environmental Science Program.</span></em></p>The globe is greening as plants grow faster in response to rising carbon dioxide. But a new analysis shows they aren’t using more water to do it - a rare piece of good news for our changing planet.Pep Canadell, CSIRO Scientist, and Executive Director of the Global Carbon Project, CSIROFrancis Chiew, Senior Principal Research Scientist, CSIROLei Cheng, Postdoctoral research fellow, CSIROLu Zhang, Senior Principal Research Scientist, CSIROYingping Wang, Chief research scientist, CSIROLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/739332017-03-03T10:10:34Z2017-03-03T10:10:34ZThe Conversation weekly quiz – #1<figure><img src="https://images.theconversation.com/files/159160/original/image-20170302-14717-3l83hz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">via shutterstock.com</span></span></figcaption></figure><p><strong>At The Conversation, we’re constantly finding out amazing new facts about the world from the academics who write for us. So to test how closely you’ve been reading this week, we’ll be running a short quiz each Friday. Answers below … if you need them.</strong> </p>
<p>1: Which 16-year-old future British monarch went to Japan and got famous Japanese tattoo artist Hori Chiyo to ink him?</p>
<p>2: Researchers have found that 55% of people involved in which activity on their mobile phones were under the age of 16? </p>
<p>3: Which iconic funk drummer, who played for Otis Redding and James Brown – and whose famous Funky Drummer drum break has been sampled in over 1,300 songs – died in late February? </p>
<p>4: Which is the UK’s third smallest city? </p>
<p>5: How much does the British curry industry contribute to the UK economy?</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=383&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=383&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=383&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=481&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=481&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159155/original/image-20170302-14717-urc5tv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=481&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">British cuisine.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/jryde/4336201294/sizes/o/">J</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>6: What function do xylem elements perform inside plants? </p>
<p>7: Which country in Eastern Europe sold people to West Germany and Israel during the Cold War? </p>
<p>8: The 19th-century scientist Luigi Galvani used electricity to animate the dismembered limbs of which animals? </p>
<p>9: Roughly how old are the world’s earliest known fossils, which have recently been discovered in Canada?</p>
<p>10: How many times do mathematicians recommend you shuffle a pack of cards to give a fair deck?</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=397&fit=crop&dpr=1 600w, https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=397&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=397&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=499&fit=crop&dpr=1 754w, https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=499&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/159154/original/image-20170302-14717-2rv4j0.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=499&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">One last time.</span>
<span class="attribution"><span class="source">Daniil Yanopulo via www.shutterstock.com</span></span>
</figcaption>
</figure>
<h2>Answers</h2>
<ol>
<li><p><a href="https://theconversation.com/ink-stigma-the-japanese-tattoo-artists-fighting-back-72943">King George V</a>. </p></li>
<li><p><a href="https://theconversation.com/why-teaching-children-about-porn-and-sexting-is-a-step-in-the-right-direction-73001">Sexting</a>. </p></li>
<li><p><a href="https://theconversation.com/the-story-of-the-funky-drummer-the-most-exploited-man-in-modern-music-73473">Clyde Stubblefield</a>. </p></li>
<li><p>The <a href="https://theconversation.com/small-cities-can-offer-just-as-much-culture-as-larger-ones-73218">City of London</a>.</p></li>
<li><p>More than <a href="https://theconversation.com/tough-immigration-laws-are-hitting-britains-curry-houses-hard-72942">£4 billion</a> a year. </p></li>
<li><p>They <a href="https://theconversation.com/scientists-create-electric-circuits-inside-plants-73711">carry water</a> from the roots to the leaves. </p></li>
<li><p><a href="https://theconversation.com/people-have-been-used-as-bargaining-chips-before-by-romanias-nicolae-ceau-escu-73141">Romania</a>. </p></li>
<li><p><a href="https://theconversation.com/awesome-erotic-everyday-the-literary-story-of-electricity-73624">Frogs</a>. </p></li>
<li><p><a href="https://theconversation.com/how-we-discovered-the-worlds-oldest-fossils-73802">Between 3.8 billion and 4.3 billion years old</a>. </p></li>
<li><p><a href="https://theconversation.com/heres-the-best-way-to-shuffle-a-pack-of-cards-with-a-little-help-from-some-maths-73176">Seven</a> (or 11, depending on how you measure fairness).</p></li>
</ol><img src="https://counter.theconversation.com/content/73933/count.gif" alt="The Conversation" width="1" height="1" />
Test your knowledge in our first ever weekly quiz.Gemma Ware, Head of AudioLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/622532016-07-12T13:22:05Z2016-07-12T13:22:05ZBotany may be dying … but somehow the plants survive<figure><img src="https://images.theconversation.com/files/130031/original/image-20160711-9271-wef2ee.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">If a plant grows and no botanist is around to classify it...</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-248095732/stock-photo-seed-root-on-soil-with-sunbeam-new-life-start-concept.html?src=jKMBxj0kKUw_gF9IwXbApw-1-59">Shutterstock/blackzheep</a></span></figcaption></figure><p>Suburban London is filled with greenery and lush growth; <a href="https://www.rt.com/business/350150-russia-grain-record-harvest/">record crop harvests</a> appear possible across Europe, and nothing too scary has been reported on the UK <a href="https://secure.fera.defra.gov.uk/phiw/riskRegister/">plant health risk register</a> for some time either – so why the doom and gloom about plants?</p>
<p>The bleak picture began with a recent report from the Royal Botanic Gardens Kew on the <a href="http://science.kew.org/strategic-output/state-worlds-plants">state of the world’s plants</a>. An accompanying newspaper article went further, saying that <a href="https://www.theguardian.com/commentisfree/2016/may/10/plants-wild-plant-species-kew">botany in the UK was dead</a>. Plants, apparently, are uncool. Looking back over a long career working with plants, I tried to remember when students flocked to study botany. Not only could I not recall those halcyon days, but I started to consider the demise of botany and the general pessimism about plant science.</p>
<p>The annual Chelsea Flower Show had over 150,000 paying visitors this year, organised as ever by the Royal Horticultural Society, whose own membership <a href="https://www.rhs.org.uk/about-the-rhs/pdfs/about-the-rhs/mission-and-strategy/past-annual-reports/accounts-for-website">nudges half a million</a>. The horticultural industry is worth over <a href="http://www.horticulture.org.uk/page.php?pageid=548">£9 billion and employs over 37,000 people</a>. All appears rosy on the garden front. Of course, there is much more to botany than just horticulture; step back into academia and there is no doubt that the <a href="http://www.tandfonline.com/doi/pdf/10.3108/beej.17.2">study of plants has declined</a>, as students have instead flocked to molecular biology and biotechnology.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/130040/original/image-20160711-9292-1az75wn.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Gone are the halcyon days of botanical study.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>But botany was never a cool subject, even when prospective students had lots of courses to choose from. My honours class in the 1970s had a mere fraction of those studying zoology. Plant taxonomy was the least popular course. The module on identifying plants, species by family, was notable for its sheer tedium, however worthy and necessary these skills are to maintaining life on earth.</p>
<p>The main beef of those lamenting the decline of botany is not that people don’t love plants or value them, but that we’re losing taxonomists. I have some sympathy for this point of view. Without a sound knowledge of plant species and their inter-relationships, we undermine the fundamentals of all living ecosystems. Plants are the bedrock of existence, as many <a href="http://richardmabey.co.uk/">authors have eloquently explored</a>, and we need people to study them. Yet the lack of botany courses in UK universities <a href="http://www.usnews.com/news/articles/2013/11/12/the-academic-decline-how-to-train-the-next-generation-of-botanists">hasn’t stopped new generations of botanists</a> appearing, keen on taxonomy and skilled in plant identification. Trainspotting of sorts is in our genes.</p>
<p>So in what new ways can budding botanists emerge? The decline of botany has been matched if not outstripped by a burgeoning of studies in ecology, biodiversity and all things environmental. I suspect that there are significant numbers of botanists in ecologist garb: the <a href="http://www.kew.org/science-conservation/plants-roots-to-riches/kathy-willis">head of Kew’s science directorate</a> is a plant ecologist, for example. Nor is plant taxonomy dead. The RHS has a <a href="https://www.rhs.org.uk/science/meet-the-team/john-david">head of horticultural taxonomy</a> (paid for with private money) and it is clear that global initiatives to map plant diversity such as Species 2000 – which aims to create “a uniform and validated index to the world’s known (plant) species” – continue to thrive.</p>
<h2>Cropped view</h2>
<p>Taxonomists in all areas of biology <a href="http://bioscience.oxfordjournals.org/content/61/12/942.full.pdf+html">agonise a lot</a> about terminal decline. The evidence doesn’t always support this <a href="http://onlinelibrary.wiley.com/doi/10.1111/cla.12019/abstract">bleak view</a>, however. More importantly, the plant debate seems to ignore agriculture. The Kew report sees agriculture as a harmful practice, threatening natural resources, destroying wild habitats and so on. But not everyone grows oil palms, and it is hardly helpful to suggest that there are good and bad plants in assessing the state of research. There are billions of people who grow plants for their livelihoods, so it’s important to look more closely at how botanists view agriculture.</p>
<p>Wild relatives of crop plants are as <a href="http://www.bioversityinternational.org/cwr/">critically endangered</a> as those with more appealing flowers and attractive foliage. Yet it will come as no surprise that the taxonomy of orchids is better known than that of bamboos. Or that <a href="http://www.chapmanhall.com/bc/sample/bc060108.pdf">in situ conservation of teosinte</a>, a wild relative of maize, is infinitely more challenging than <a href="https://www.croptrust.org/our-mission/">setting up seed banks</a>. Kew’s interest in economically important plants has <a href="http://www.kew.org/science-conservation/collections/economic-botany/history">stuttered over the years</a>. Visitors will <a href="http://www.kew.org/visit-kew-gardens/explore/attractions">struggle to find</a> anything about agriculture when planning their itinerary, although plant scientists behind the scenes continue to study some key groups, such as palms. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/130041/original/image-20160711-9289-12nx4fg.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Eggplants en masse.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Beyond the taxonomy debate, there is a wider concern for the <a href="http://bsbi.org/about-bsbi">teaching of whole plant biology</a>. Again, I share this worry, although the scope of the concern seems unduly narrow. Despite the rise of molecular biology and genetics, there are still many countries where botany or plant science courses still exist. Want to study taxonomy? Go to Eastern Europe, Brazil, or the US, where plant sciences continue to thrive.</p>
<p>People come to plants from many directions. The <a href="https://www.bgci.org/garden.php?id=3634">Brackenhurst Botanical Garden</a> in Kenya was brought back to life by a zoologist who is a more passionate botanist than I ever was. The study of plants has been reinvented and, as scientists, we should take a more rounded view of where plants grow and who grows them. Who knows, maybe botany will one day become cool after all.</p><img src="https://counter.theconversation.com/content/62253/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Eric Boa does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Traditional botanists are in decline, but this isn’t the end of plant science.Eric Boa, Research fellow, University of AberdeenLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/595042016-05-24T09:49:25Z2016-05-24T09:49:25ZThe flower breeders who sold X-ray lilies and atomic marigolds<p>The <a href="https://www.rhs.org.uk/shows-events/rhs-chelsea-flower-show">Chelsea Flower Show</a>, one of the biggest and best known horticultural shows in the world, is now open. In the coming days, some <a href="http://www.standard.co.uk/goingout/attractions/chelsea-flower-show-2016-tickets-times-highlights-and-travel-info-a3252546.html">150,000</a> visitors will make their way to the Royal Hospital Chelsea, expecting to be wowed by innovative garden designs and especially by gorgeous flowers. Among other things, show-goers will have a chance to learn the winner of the Royal Horticultural Society’s <a href="https://www.rhs.org.uk/shows-events/rhs-chelsea-flower-show/2015/articles/Plant-of-the-Year">Plant of the Year</a> award. This annual prize goes to the “most inspiring new plant” on display at the show – a high honour indeed given the number and range of varieties introduced each year.</p>
<p>The relentless pursuit of showy flowers for garden display extends back significantly further than the 104 years of the Chelsea show. One need only recall the <a href="https://www.rijksmuseum.nl/en/explore-the-collection/timeline-dutch-history/1637-tulipmania">infamous Dutch tulip craze</a> of the 17th century to be reminded that fascination with floral novelties has a long and storied history. </p>
<p>Over the centuries, entrepreneurial cultivators have endeavoured to create unique plant varieties, either by bringing together the genetic material from established lines through <a href="http://www.biologyreference.com/Ho-La/Hybridization-Plant.html">hybridisation</a> or through the discovery of new genetic variation such as a chance mutation in a field. Today, flower breeding is pursued with a far better understanding of plant biology than ever before, in some cases with the aid of technologies such as tissue culture and genetic transformation. Yet the goal remains the same: the creation of tantalising tulips, ravishing roses, show-stopping snapdragons and myriad other plants that will ideally prove irresistible to gardeners and turn a handsome profit.</p>
<p>The quest to produce profitable new varieties – and to do so as fast as possible – at times led to breeders to embrace <a href="http://press.uchicago.edu/ucp/books/book/chicago/E/bo24313051.html">methods that today seem strange</a>. There is no better illustration of this than the mid-century output of one of America’s largest flower-and-vegetable-seed companies, <a href="http://www.burpee.com/">W Atlee Burpee & Co</a>. </p>
<h2>Gardening with X-rays</h2>
<p>In 1941, Burpee Seed introduced a pair of calendula flowers called the “X-Ray Twins”. The company president, <a href="https://flic.kr/p/gaYqK">David Burpee</a>, claimed that these had their origins in a batch of seeds exposed to X-rays in 1933 and that the radiation had generated mutant types, from which the “X-Ray Twins” were eventually developed.</p>
<p>At the time, Burpee was not alone in exploring whether X-rays might facilitate flower breeding. Geneticists had only recently come to agree that radiation could lead to genetic mutation: the possibilities for creating variation “on demand” now seemed boundless. Some breeders even hoped that X-ray technologies would help them press beyond existing biological limits. </p>
<p>The Czech-born horticulturist Frank Reinelt thought that subjecting bulbs to radiation might help him produce an elusive red delphinium. Unfortunately, the experiment did not produce the hoped-for hue. Greater success was achieved by two engineers at the General Electric Research Laboratory, who produced – <a href="https://patents.google.com/patent/USPP165P">and patented</a> – a new variety of lily as a result of their experiments in X-ray breeding.</p>
<p>Though Reinelt’s and other breeders’ tangles with X-ray technology resulted in woefully few marketable plant varieties, David Burpee remained keen on testing new techniques as they appeared on the horizon. He was especially excited about methods that, like X-ray irradiation, promised to generate manifold genetic mutations. He thought these would transform plant breeding by making new inheritable traits – the essential foundation of a novel flower variety – available on demand. He estimated that “in his father’s time” a breeder chanced on a mutation “once in every 900,000 plants”. He and his breeders, by comparison, equipped with X-rays, UV-radiation, chemicals, and other mutation-inducing methods, could “turn them out once in every 900 plants. Or oftener”.</p>
<h2>Scientific sales pitches</h2>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=930&fit=crop&dpr=1 600w, https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=930&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=930&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1169&fit=crop&dpr=1 754w, https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1169&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/123630/original/image-20160523-11025-1sr1nq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1169&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A 1973 Burpee cover.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/burpee/167768850/in/album-72157594166703655/">Burpee</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>Burpee’s numbers were hot air, but in a few cases plant varieties produced through such methods did prove hot sellers. In the late 1930s Burpee breeders began experimentation with a plant alkaloid called <a href="https://archive.org/details/useofcolchicinei3424derm">colchicine</a>, a compound that sometimes has the effect of doubling the number of chromosomes in a plant’s cells. They exploited the technique to create new varieties of popular garden flowers such as marigold, phlox, zinnia, and snapdragons. </p>
<p>All were advertised as larger and hardier as a result of their chromosome reconfiguration – and celebrated by the company as the products of “chemically accelerated evolution”. The technique proved particularly successful with snapdragons, giving rise to a line of “Tetra Snaps” that were by the mid-1950s the best-selling varieties of that flower in the United States.</p>
<p>Burpee’s fascination with (in his words) “<a href="https://books.google.co.uk/books?id=IEEEAAAAMBAJ&pg=PA15">shocking mother nature</a>” to create novel flowers for American gardeners eventually led him to explore still more potent techniques for generating inheritable variation. He even had some of the company’s flower beds seeded with radioactive phosphorus in the 1950s. These efforts do not appear to have led to any new varieties – Burpee Seed never hawked an “atomic-bred” flower – but the firm’s experimentation with radiation did result in a new Burpee product. Beginning in 1962, they offered for sale packages of “atomic-treated” marigold seeds, from which home growers might expect to grow a rare white marigold among other oddities.</p>
<p>Burpee was, above all, a consummate showman and a master salesman. His enthusiasm for the use of X-rays, chemicals, and radioisotopes in flower breeding emerged as much from his knowledge that these methods could be effectively incorporated into sales pitches as from his interest in more efficient and effective breeding. Many of his mid-century consumers wanted to see the latest science and technology <a href="http://dx.doi.org/10.1017/S0007087412001057">at work in their gardens</a>, whether in the form of plant hormones, chemical treatments, or varieties produced through startling new techniques. </p>
<p>Times have changed, 60-odd years later. Chemicals and radiation are as more often cast as threatening than benign, and it is likely that many of today’s visitors to the Chelsea Flower Show hold a different view about the kinds of breeding methods they’d like to see employed on their garden flowers. But as the continued popularity of the show attests, their celebration of flower innovations and the human ingenuity behind these continues, unabated.</p><img src="https://counter.theconversation.com/content/59504/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Helen Anne Curry does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The relentless pursuit of showy flowers for garden display – as seen at Chelsea Flower Show – has seen some odd uses of radiation and chemicals .Helen Anne Curry, Peter Lipton Lecturer in History of Modern Science and Technology, University of CambridgeLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/546982016-03-11T11:12:33Z2016-03-11T11:12:33ZCan we ‘vaccinate’ plants to boost their immunity?<figure><img src="https://images.theconversation.com/files/114727/original/image-20160310-26261-7ib0hc.jpg?ixlib=rb-1.1.0&rect=221%2C786%2C2767%2C1476&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Our modern crops need some help in the immunity department.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/ndrwfgg/173181035">Andy / Andrew Fogg</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>When you pick up the perfect apple in the supermarket it’s easy to forget that plants get sick just like we do. A more realistic view might come from a walk outside during summer: try to find a leaf without a speck, spot or blemish. Tough, huh? Those are the signs of a microscopic battle waged every day in and on plants.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=463&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=463&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=463&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=582&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=582&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114742/original/image-20160310-26279-stkxxv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=582&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Plants get sick too.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Lumbar_plant_acerleaf_sick.jpg">Carsten Niehaus</a></span>
</figcaption>
</figure>
<p>Just like us, plants are covered in microbes. And just like us, plants have evolved an immune system to protect against the dangerous ones. But our current agricultural system works against plants’ natural immune defenses, by limiting the tools plants have to fight back and restricting evolution of new tools. </p>
<p>Pesticides provide us with most of the spotless produce in the grocery store. Even so, many apples still don’t make it to market. About a <a href="https://www.usitc.gov/publications/332/ITS_4.pdf">third end up</a> as juice or applesauce, because they don’t meet the beauty standards of the American consumer. Forget about blemishes – <a href="http://panamadisease.org/en/theproblem">Panama Disease</a> threatens nearly all of the world’s banana production, and the only effective treatment is toxic to the soil.</p>
<p>Scientists studying plant immunity are figuring out how to fight plant diseases without chemical pesticides. Some researchers plan to <a href="https://theconversation.com/primed-for-battle-helping-plants-fight-off-pathogens-by-enhancing-their-immune-systems-43689">give our crops vaccines</a>, just like the shots we administer to ourselves to fend off the flu or smallpox. My lab seeks to identify ways plants defend themselves in the wild. With that information, we can use modern breeding techniques and genetic engineering to strengthen the immunity of our crops and gardens.</p>
<h2>Plants have naturally evolving “resistance genes”</h2>
<p>Over the last 25 years, advances in genetics and molecular biology have revealed new secrets of <a href="https://en.wikipedia.org/wiki/Plant_disease_resistance">plant immunity</a>. Computers, searching mountains of plant genetic data, have identified thousands of “<a href="http://prgdb.crg.eu/wiki/Main_Page">resistance genes</a>” that <a href="http://doi.org/10.1038/nature05286">help plants fend off infection</a>.</p>
<p>These genes are the blueprints for resistance proteins that look surprisingly like the antibodies in the human immune system. Both are modular in nature and recognize specific invading pathogens. Like a lock and key, only the proper resistance protein “lock” will recognize its corresponding pathogen “key.”</p>
<p>Resistance proteins also contain a switch to alert the plant that a potential threat has been found. Without the proper lock and key combination, the plant never knows the pathogen is there. If the resistance protein identifies a pathogen, other immune functions and defenses turn on to fight the intruder and attempt to keep the plant from getting “sick.” </p>
<p>Animals’ immunity has a distinct advantage over plants’, though. New <a href="http://www.imgt.org/IMGTeducation/Tutorials/ImmuneSystem/UK/the_immune_system.pdf">antibodies are made fresh by human immune cells</a> to recognize new pathogens we might encounter. Plants are stuck with what they’ve got. All the resistance genes they have were passed down from their parents.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114764/original/image-20160311-26274-5p03tr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Modern farms support much less diversity – and contain less immunity – than a natural wildflower field.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/barbarawalsh/5944251580">Barbara Walsh</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Diversity is a key part of plant immune systems</h2>
<p>Bacteria and fungi with short life cycles can evolve more quickly than plants. These pathogens can complete a life cycle in a week and produce millions of offspring. If even one changes or drops the molecular “keys” recognized by a resistance protein, it could start a new family of pathogens capable of infecting the plant.</p>
<p>Due to the rigidity of inherited resistance, only genetic variety among a plant species can provide a variety of resistances to pathogens. The more diverse the population of plants, the more diverse the resistance genes in the population. </p>
<p>Resistance genes’ modular nature allows computers to find them, and is also critical for their evolution. This characteristic allows for quick rearrangements and new combinations. The mixing of genes during plant sex can lead to new chimeric resistance genes made of bits and pieces of the parents’ genes. Even as the pathogens change to evade the plant, resistance genes can evolve over the generations to recognize and fight them. </p>
<p>Human beings’ <a href="http://www.fao.org/docrep/007/y5609e/y5609e02.htm">reliance on monoculture</a> for our food supply <a href="http://doi.org/10.1016/j.soilbio.2013.06.007">works against</a> the plants’ natural defenses. Without a variety of resistance gene modules to work with, the plant community struggles to hit on new winning combinations. Not only are we halting the natural evolution of resistance genes, but if every plant in the field is identical, then disease that infects one can infect them all.</p>
<p>The plant pathogens are evolving, but we continue to grow the same plants, with the same resistance genes. To compensate, we rely <a href="http://quickstats.nass.usda.gov">more and more on pesticides</a> to keep our crop plants healthy. Without new resistance genes our <a href="https://www.washingtonpost.com/news/wonk/wp/2015/12/04/the-worlds-most-popular-banana-could-go-extinct/">current crops of bananas</a> and <a href="http://www.nature.com/news/planetary-disasters-it-could-happen-one-night-1.12174">potatoes may fail</a>. </p>
<h2>Compensating for the diversity our crops lack</h2>
<p><a href="http://www.fralin.vt.edu/affiliated-faculty/john-mcdowell">Our lab</a> and collaborators seek to find resistance genes in wild relatives of the soybean to <a href="http://dx.doi.org/10.1094/PDIS-08-15-0916-RE">breed into commercial varieties</a>. We play the role of natural selection by choosing diverse resistance that protects against economically important diseases.</p>
<p>Breeding can be slow and is especially difficult if the plants are only distantly related. So other labs and companies are using genome editing technologies to introduce new resistance genes quickly.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/114762/original/image-20160310-26271-1o9a4mr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A potato suffering from late blight, the disease responsible for the Irish potato famine.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/usdagov/5050443007">U.S. Department of Agriculture</a>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p>Take the example of potatoes and late blight, the disease that caused the Irish potato famine in the 19th century. Today, farmers spray fungicide as many as <a href="http://www.ipm.ucdavis.edu/PMG/r607101211.html">15 times a year</a> to combat the disease on potatoes. A <a href="http://dx.doi.org/10.1046/j.1365-313X.2003.01934.x">decade of research</a> identified and isolated a resistance gene in wild potato to fight late blight. Chemical company BASF genetically modified (GM) cultivated potato varieties in an attempt to market a GM, disease-resistant product. The <a href="http://www.rsc.org/chemistryworld/2013/02/basf-gm-potato-amflora">project was abandoned</a> in 2013 due to lack of interest and high regulatory barriers.</p>
<p>US regulators have recently approved new <a href="http://www.simplotplantsciences.com">“Innate” potato</a>, a GM variety with resistance genes from wild potato relatives. These potatoes recognize, and fight back against late blight – without the help of fungicide. </p>
<p>The use of genetic modification in food is still controversial. Many think GM plants need more testing; others say they are not natural. <a href="http://bigstory.ap.org/article/94da41eac8a64ff8a14b072bcd14fe0a/fda-gives-ok-companys-genetically-engineered-potato">McDonald’s will not use the Innate potato</a> for its French fries. Everyone can buy and eat as they choose. But sometimes I want to bite into that perfect red apple or enjoy a bag of French fries. For me, at least, the potato plant fighting for itself with the help of an added gene is more appealing than weekly applications of <a href="http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/chlorothalonil-ext.html">fungus-killing chemical chlorothalonil</a>. </p>
<p>Some scientists are going a step further. Just this year researchers showed how they <a href="http://doi.org/10.1126/science.aad3436">customized a resistance gene</a>. In this case, rather than borrowing from nature, the “locks” have been engineered in the lab to recognize a specific pathogen “key.” Putting the new resistance gene in plants confers synthetic immunity.</p>
<p>This research is still only at the in-the-lab stage, but it opens the hopeful possibility that even if diseases evolve to evade all natural plant resistance, we can engineer tools to stop them.</p><img src="https://counter.theconversation.com/content/54698/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Herlihy is a graduate student at Virginia Tech, and receives funding from Virginia Tech and North Carolina State University. </span></em></p>Modern agriculture is synonymous with monoculture. That lack of diversity is bad news for plants’ natural immune defenses. Researchers are figuring out how to help plants fend off microbes – without pesticides.John Herlihy, Ph.D. Student in Plant Pathology, Physiology and Weed Science, Virginia TechLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/472352015-12-22T11:22:06Z2015-12-22T11:22:06ZPlant viruses: from crop pathogens to key players in bio-nanotechnology<figure><img src="https://images.theconversation.com/files/106468/original/image-20151217-8081-2ykemk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Orchid infected with the Tobacco mosaic virus. </span> <span class="attribution"><span class="source">Department of Plant Pathology Archive North Carolina State University - USDA Forest Service</span></span></figcaption></figure><p>Plant viruses are sub-microscopic parasites that have been studied primarily because they cause devastating diseases in crop plants. But in recent years, scientists have discovered they’re not just bad news; they also form symbiotic relationships with plants and the microbes they host. </p>
<p>Moreover, plant virus genomes have been engineered for use in <a href="http://www.hindawi.com/journals/bmri/2015/932161/">gene delivery</a> and are also being increasingly used as <a href="http://www.ncbi.nlm.nih.gov/pubmed/22038411">nanoparticles in bio-nanotechnology</a>. </p>
<h2>A range of symptoms</h2>
<p>More than 1000 virus species have been described that infect cultivated plants worldwide. They have the capacity to cause major epidemics and total crop loss, which is particularly devastating in developing countries that depend on a few staple crops for food security and income. For example, the <a href="http://www.cabi.org/isc/datasheet/2747">Cassava Mosaic Disease</a> epidemic in many African countries is caused by several species of <a href="http://viralzone.expasy.org/all_by_species/111.html">Begomoviruses</a>, including African Cassava Mosaic Virus. These are transferred from plant to plant by whiteflies.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=305&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=305&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=305&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=383&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=383&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106490/original/image-20151217-8093-b3n0oy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=383&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Plum pox in apricot.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Plum_pox#/media/File:Plum_pox_in_apricot.jpg">wikimedia</a></span>
</figcaption>
</figure>
<p>Often viruses do not completely destroy crops but decrease their yield and quality. In fruit and vegetable crops, <a href="http://www.cabi.org/isc/datasheet/42203">Plum pox</a> virus affects stone fruit trees, while <a href="http://www.apsnet.org/edcenter/intropp/lessons/viruses/Pages/TomatoSpottedWilt.aspx">Tomato spotted wilt </a> and <a href="http://westernfarmpress.com/controlling-tomato-yellow-leaf-curl-virus">Tomato yellow leaf curl</a> viruses cause severe losses in tomatoes. <a href="http://www.potatovirus.com/index.cfm/page/pvyinfo.htm">Potato virus Y</a> affects potatoes and many vegetables.</p>
<p>Even more benign viruses can build up in planting material of crops propagated through cuttings, roots or tubers. This leads to degeneration and yield losses in subsequent growing seasons. In potato production systems, virus incidence can be high with tubers infected with five or six different viruses. Such degeneration depresses both yield and quality. <a href="http://link.springer.com/article/10.1007%2Fs11540-011-9190-5">Studies in sub-Saharan Africa</a> have shown that yield increases of 30-50% are possible when farmers replenish their stock with healthy planting material. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=928&fit=crop&dpr=1 600w, https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=928&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=928&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1167&fit=crop&dpr=1 754w, https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1167&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/106502/original/image-20151217-8109-148y7ns.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1167&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">17th century watercolor.</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Tulip_mania#/media/File:Semper_Augustus_Tulip_17th_century.jpg">wikimedia</a></span>
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</figure>
<p>However, in the past not all virus symptoms were thought to be bad. The symptoms of <a href="https://www.rhs.org.uk/advice/profile?PID=254">Tulip breaking virus</a> – broken colour on the petals – can be seen in the 17th century paintings of Dutch masters, for example. At that time, bulbs giving rise to such flowers were highly prized. It was only in the 20th century that these bulbs were known to be infected with a virus. </p>
<p>Plant viruses can be detected by fast and sensitive laboratory methods. In addition, virus spread can be controlled with pesticides which kill the natural vectors such as insects or nematodes that transmit viruses from plant to plant. Many types of insects transmit viruses, including aphids, thrips and whiteflies – and their populations are increasing in size and geographic range, an effect expected to increase with global warming. For that reason host resistance is the most sustainable and effective way to control viruses in crop plants.</p>
<h2>Good viruses</h2>
<p>Recent studies have shown that many plants in natural populations are infected with viruses – many of which cause <a href="http://www.nature.com/nrmicro/journal/v9/n2/full/nrmicro2491.html">no obvious symptoms</a> but persist and are transmitted by seed to subsequent generations. The reason for these cryptic virus-host associations is not yet clear. However, as occurs in other host-virus interactions in mammals or bacteria, some viruses can exist in symbiotic association and have a beneficial effect. A good example is <a href="http://www.sciencemag.org/content/315/5811/513.abstract">a study</a> of <a href="http://www.tropicalforages.info/key/Forages/Media/Html/Panicum_maximum.htm">tropical panic grass</a> growing in Yellowstone National Park where the soil temperature can exceed 50°C. The grass can only tolerate these conditions through a symbiotic association with a fungus infected with a virus. </p>
<p>Several disease-causing plant viruses can also protect their host plants from abiotic stresses such as cold or drought conditions. Plants infected with <a href="https://www.rhs.org.uk/advice/profile?pid=143">Cucumber mosaic</a>, <a href="http://viralzone.expasy.org/all_by_protein/134.html">Brome mosaic</a> and <a href="http://www.extension.umn.edu/garden/yard-garden/vegetables/tomato-tmv-disease/">Tobacco mosaic viruses</a> tolerate drought conditions better than uninfected plants. Tobacco mosaic virus was first recognised as an infectious agent in 1898 and research on it continues to push the boundaries of knowledge, including in bio-nanotechnology. </p>
<p>Plant viruses are natural nanoparticles, and viruses such as the tubular rod-shaped Tobacco mosaic virus and icosahedral <a href="http://www.ncbi.nlm.nih.gov/pubmed/20455698">Cowpea mosaic virus</a> have been used in a number of applications. By genetically manipulating the virus genomes and inserting gene coding for other molecules, scientists have managed to make host plants infected with the virus produce additional molecules. The molecules can be expressed fused to the surface of the virus particles or expressed as free protein. We can then harvest the leaves of the plants and purify the molecules for vaccines or other <a href="http://www.pharmaceutical-technology.com/features/feature122248/">valuable pharmaceuticals</a>.</p>
<p>An emerging area is to use virus particles as “nanoscaffolds”. Here, the particle surfaces are genetically or chemically altered and certain compounds, peptides and enzymes are added. For example, nano structures based on the Tobacco mosaic virus can stabilise magnetic liquids in transistor components. In fact, the future use of plant viruses as components in materials-, plant- and biomedical sciences is only limited by our imagination.</p><img src="https://counter.theconversation.com/content/47235/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lesley Torrance receives funding from the BBSRC and the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS). </span></em></p>They’re good, they’re bad and they’re useful: we are still discovering what we can do with plant viruses.Lesley Torrance, Professor of Plant Biology, University of St AndrewsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/387322015-04-08T16:45:28Z2015-04-08T16:45:28ZThe cutting-edge science taking on some of the world’s most notorious parasitic plants<figure><img src="https://images.theconversation.com/files/77235/original/image-20150407-26515-1r900zh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Can you spot the crop?</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?lang=en&language=en&ref_site=photo&search_source=search_form&version=llv1&anyorall=all&safesearch=1&use_local_boost=1&searchterm=parasite%20plants&show_color_wheel=1&orient=&commercial_ok=&media_type=images&search_cat=&searchtermx=&photographer_name=&people_gender=&people_age=&people_ethnicity=&people_number=&color=&page=1&inline=213863116">ShutterStock </a></span></figcaption></figure><p>Thousands of plant species have adopted a “parasitic” mode of life, living off a host plant which supplies it with water and nutrients. Most of these remain harmless, but a few have evolved to become serious agricultural weeds that threaten food security in some of the world’s poorest regions.</p>
<p>Parasitic plants are deceptively common, you have probably come across the snarling strands of Dodder – a stem parasite which infects nettles – in a local hedgerow. Even the world’s largest flower, <em>Rafflesia arnoldii</em>, found in the rainforests of South-East Asia, is a parasite, infecting and living off tropical vines.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/77237/original/image-20150407-26496-1phdx4f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">A tropical parasite.</span>
<span class="attribution"><a class="source" href="http://upload.wikimedia.org/wikipedia/commons/8/86/Rafflesia_80_cm.jpg">ma_suska</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Plundering reserves</h2>
<p>What unites all parasitic plants is their ability to locate a host plant – usually through recognition of specific chemicals – and form an organ called the haustorium. This organ forces its way into the host plant stem or root and allows the parasite to freely withdraw nutrients to fuel its own growth and reproduction, plundering the host’s reserves. When the host in question is an important agricultural crop, this can have devastating consequences for the farmer. </p>
<p>Perhaps the most notorious example of a parasitical weed in agriculture is <em>Striga hermonthica</em> – a root parasite which infects all major cereal crops. Usually found in Sub-Saharan Africa, farmers call it “witchweed” because it has a shrinking effect on the host plant, causing it to be stunted and dramatically reducing yields. As the parasite germinates underground, a farmer will have no idea if his plants are infected until the parasite sends up shoots of delicate (and ironically beautiful) purple flowers. At this point, it is too late and his harvest is doomed. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/77238/original/image-20150407-26479-1g4i7rb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">A beautiful nightmare for cereal farmers.</span>
<span class="attribution"><a class="source" href="http://upload.wikimedia.org/wikipedia/commons/9/9d/Striga_bilabiata_MS4167.jpg">Marco Schmidt</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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</figure>
<p>Worse still, the land becomes practically useless as <em>Striga</em> seeds can remain dormant for decades to ruin any future harvests. As a result, <em>Striga hermonthica</em> is thought to be the largest biological constraint on cereal production in Sub-Saharan Africa, causing <a href="http://www.ncbi.nlm.nih.gov/pubmed/20153240">annual losses in the region of US$10 billion</a>. </p>
<h2>Suicidal germination</h2>
<p>There are few ways to protect crops from parasites such as <em>Striga</em>. One method however, is to induce “suicidal germination” of the parasite seed by treating the soil with host-derived compounds – which induces the seeds to germinate. In the absence of a host, the parasite seeds cannot survive and die, allowing the soil to be sown for crops.</p>
<p>Another strategy is applying herbicides to the seeds of herbicide-resistant crops to prevent the parasite from attaching. Such chemicals, however, are too expensive for subsistence farmers who are left with labour-intensive options such as rotating crops with non-host species and weeding out the emerged parasite shoots by hand. </p>
<p>Biological control may be an alternative; the legume <em>Desmodium uncimatum, _for instance, appears to suppress _Striga</em> infestations. Curiously, <em>Desmodium</em> also repels another serious pest, the stem borer moth, making it a highly attractive form of <a href="http://www.rothamsted.ac.uk/science-stories/push-pull-africa">natural control</a>. </p>
<h2>Breeding the solution</h2>
<p>The most effective approach to date has been using naturally resistant crops, carefully selected through traditional plant breeding techniques. In some cases, the resistant host produces lower levels of germination stimulants, whereas in others the parasite is physically prevented from entering the host stem or root. </p>
<p>A problem with these cultivars is that they tend to be found among wild relatives of crop species which also have poor yield. It can take decades to breed parasite-resistant traits into commercial plants using traditional techniques. Genetic engineering is not currently an option as the genes supporting these traits have not been identified. Research groups are currently focused on identifying these resistance genes, so that they can be used to develop “DNA-markers” that can detect resistant plants early and so speed up the breeding progress. </p>
<p>Some of these resistant responses do occur in commercial crops, however an over-reliance on these has triggered the evolution of more virulent parasites and it is a constant race against time to identify new sources of resistance. If enough resistant genes are identified, plant breeders hope to incorporate them in a single crop to provide long term resistance. </p>
<h2>Genetic control</h2>
<p>Certain research groups have also begun to experiment with “RNA interference” (RNAi) technology. This is based on using short strands of ribonucleic acid – a biological coding material very similar to DNA – that can be used to disrupt expression of genes essential for parasitic plants to function. If the host plant is engineered to express RNAi strands that target parasite genes, then the parasite can be suppressed without any detrimental effect on the host. This has been successful in <a href="http://www.ncbi.nlm.nih.gov/pubmed/19490480">protecting tomatoes</a>, but not for cereal crops against <em>Striga</em>. </p>
<p>Apart from being huge agricultural pests, researchers study parasitic plants because there’s still so much we don’t know about this fascinating group of plants. For example, we have yet to fully understand how parasites overcome the host immune system or exactly which substances it absorbs from the host plant. </p>
<p>My own research PhD is investigating what defence pathways may underpin resistant responses to <em>Striga gesnerioides</em> – a species closely related to <em>Striga hermonthica</em> but which infects cowpea. It is clear that within my own area of research, besides the field of parasitic plants as a whole, there is more than enough to inspire scientists for many decades to come.</p><img src="https://counter.theconversation.com/content/38732/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Caroline Wood is a PhD student at the University of Sheffield, for a lab group which conducts research on parasitic plants. She receives funding from the Unviersity of Sheffield and, previously, from Syngenta.</span></em></p>Little is known about how parasitic plants live side-by-side with their hosts. But new genetic techniques may help scientists gain further insights.Caroline Wood, PhD student in Plant Biology, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/330482014-10-20T14:57:41Z2014-10-20T14:57:41ZPlants can actually take care of their offspring – here’s how<figure><img src="https://images.theconversation.com/files/61861/original/rv9gkk6k-1413385943.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Where's mother?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/66176388@N00/5669437281">Mark Robinson</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>Plants may not travel around as animals do, but they have evolved many strategies that allow them to cope and make the most of the environment they live in. Examples can be found everywhere. For instance, succulence is the special characteristic that cacti have to store water and then use it as a reserve in their dry habitats. And there are plants that produce seeds that are dispersed by wind, allowing them to travel farther than they could possibly have gone otherwise.</p>
<p>What is not yet quite accepted is that plants can also take care of their “children”, or seedlings. This is partly because it is well known that plants do not have a nervous system and therefore they don’t have a “will” to protect their descendants. But, in fact, they do have mechanisms for offspring care. </p>
<p>One example in which offspring care is observed in plants is in the little cactus (less than 3cm in diameter) called <em><a href="http://www.iucnredlist.org/details/152282/0">Mammillaria hernandezii</a></em>. This inhabits a semi-arid zone in Mexico, where rain is a scarce resource and comes intermittently. So the plants that inhabits this type of habitat go through cycles of hydration and dehydration. </p>
<p>The special characteristic about <em>M. hernandezii</em> is that it is serotinous, which means that it will keep a portion of the seeds that it produces inside the stem, and release the rest. Being serotinous has many advantages. It can help in protecting the offspring from seed hunters, such as ants. It can also allow the delayed release of seeds when conditions in the environment are best for germination. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/61860/original/pcz7bxkv-1413385832.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Mammillaria hernandezii.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/carnwrite/11302631634/in/photolist-wRZpe-idLWBd">carnwrite</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-nd/4.0/">CC BY-NC-ND</a></span>
</figcaption>
</figure>
<p>In <a href="http://www.ncbi.nlm.nih.gov/pubmed/23345416">a study</a> we compared seeds that were kept inside the parent plant for a year, against recently produced seeds that are not kept inside the parental plant. We looked at various aspects to evaluate whether the parent plant is looking after its offspring. </p>
<p>First we tested differences in germination in survival percentage and found that older seeds, kept inside the parental plant, germinate and survive more than young seeds, which are released immediately after their production. </p>
<p>We also found that older seeds possessed special proteins, which indicated that these seeds had experienced the rain pulses and the periods of drought. This adaptation to its natural environment wasn’t present in young seeds that hadn’t had the time to experience these environmental changes.</p>
<p>Then we also found that young seeds that are released in the soil were more likely to be eaten by predators or rotted by micro-organisms compared to older seeds that had been protected inside the parental plant. </p>
<p>And finally, we wanted to find out whether the release of seeds was triggered by the presence of water. And it seems that, in the presence of enough water, older seeds kept inside the parental plant are indeed released into the soil for germination.</p>
<p>In short, while inside the mother plant, the seeds experience the stress of the habitat they live in, including pulses of rain and the lack of it. But by learning from this experience, while still being protected by the mother plant, the seeds are more prepared to face the unpredictability of their habitat. The seeds do this by producing special proteins that make them stronger when it comes to germination. </p>
<p>Another mechanism plants have for giving their offspring a head start involves sharing roots with their parent. This is thought to ensure the seedling a good start, until it can be independent enough to survive from its own roots and nutrients. </p>
<p><a href="http://forestry.about.com/od/forestfire/a/Serotiny.htm">Many other plants</a> have evolved this feature of seed retention (or serotiny). Take the example of serotinous conifers found in areas where forest fires are common. In their case, the cue to release the seeds from the mother plant is not water but fire. The thing these plants share in common is the fact that the parental plant will look after its little babies and will protect them in order to ensure them a better future.</p><img src="https://counter.theconversation.com/content/33048/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bianca A. Santini receives funding from The National Council of Science and Technology in Mexico (CONACyT).</span></em></p>Plants may not travel around as animals do, but they have evolved many strategies that allow them to cope and make the most of the environment they live in. Examples can be found everywhere. For instance…Bianca A. Santini, PhD student in Animal and Plant Sciences, University of SheffieldLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/257652014-04-22T12:59:29Z2014-04-22T12:59:29ZSpying on plant communication with tiny bugs<figure><img src="https://images.theconversation.com/files/46709/original/z8k9ts93-1397751836.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">I'm catching some signals, fellow aphid. Are you?</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/drriss/8999852104">drriss</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span></figcaption></figure><p>Internal communications in plants share striking similarities with those in animals, <a href="http://onlinelibrary.wiley.com/doi/10.1111/nph.12807/abstract">new research reveals</a>. With the help of tiny insects, scientists were able to tap into this communication system. Their results reveal the importance of these communications in enabling plants to protect themselves from attack by insect pests.</p>
<p>Like any organism, plants need to transport essential nutrients from one part to another. This is achieved by two parts of the plant: the xylem and the phloem. Xylem, which is largely made of dead cells, transports water and dissolved nutrients obtained by roots up to the aerial tissues of the plants. By contrast, the phloem is made up of living cells – active tubes that transport a syrupy sap, rich in sugars made by photosynthesis in the leaves.</p>
<p>In the 1980s, scientists discovered that phloem cells also function as a communication system through which electrical signals travel. This is similar to the electrical signals transmitted through the neurons in your nervous system.</p>
<p>In both plants and animals, electrical signals function in an analogous manner. They transmit information from one location to another. If someone wounded your hand, an electrical signal travels through neurons from your skin, up your arm, to your brain, to let you know you have been wounded, and to draw your hand away. Similarly, when a herbivore wounds a plant, an electrical signal is generated which, instead of travelling to a centralised brain, travels through the phloem to other parts of the plant, informing them that wounding has occurred.</p>
<h2>Tapping into defence</h2>
<p>Wounding means danger in plants because it normally happens when the plant is becoming some herbivore’s meal. The ability of a wounded part of the plant to let other parts know that wounding has occurred can help prepare against the attack. Plants have a suite of <a href="https://theconversation.com/plants-release-chemical-weapons-and-deploy-insect-armies-in-their-defence-24853">sophisticated defences</a> that they can bring to bear to protect themselves from herbivores.</p>
<p>Some herbivores don’t wound plants as much as they nibble. Nibbling may escape the detection of the plant, but could have dire consequences—a lot of nibbling can be as fatal as a big bite. But it has been difficult to determine if plants are able to detect nibbling and transmit a warning signal, in the same manner as they do when wounded.</p>
<p><a href="http://www.researchgate.net/profile/Vicenta_Salvador_Recatala">Vicenta Salvador-Recatalà</a> of the University of Lausanne and her colleagues used aphids – specialised insects that feed on plants – to find out how the phloem network responds to nibbling by caterpillars. Their results have been published in the journal <a href="http://onlinelibrary.wiley.com/doi/10.1111/nph.12807/abstract">New Phytologist</a>.</p>
<p>Aphids feed by using their straw-like mouths, which penetrate deep into the plant. As long as there aren’t too many aphids, it doesn’t harm the plant much. In fact, it is in the aphid’s interest to ensure that the plant remains healthy, so that there is still plenty of its sugary syrup to be had.</p>
<p>Aphids don’t just connect themselves to the internal plumbing; they’re also tapped in to the plant’s internal communication system. The aphid’s mouth drills into the phloem, is not easily dislodged, and doesn’t break. This means that aphids that are attached to the plant’s phloem can then be converted into living electrodes. A living-aphid-electrode system can be used to detect electrical signals transmitted through the plant body without causing additional damage to the plant – damage that can set off the plants’ warning system and confuse the results.</p>
<p>Using this aphid phloem-tapping system, Salvador-Recatalà and colleagues investigated the transmission of electrical signals in response to caterpillar feeding. They found that even the nibbling of caterpillars could induce electrical signals, on a smaller scale, but akin to those transmitted by wounding.</p>
<p>The electrical signals travelled like waves, spreading most rapidly to leaves that were closest to the site of caterpillar feeding, and more slowly to other regions of the plant. When the waves were rapid, a wound response was activated on surrounding leaves – beyond the one that the caterpillar was nibbling on.</p>
<h2>Behaving like animals</h2>
<p>In neurons in animals, electrical waves are transmitted by virtue of changes in the way charged atoms flow into and out of the cell. The flow of these charged atoms is controlled by protein channels embedded in the membrane of neurons. In the absence of a signal, the channels are closed. When a neuron receives the right signal, these channels open, allowing the ions to flow out through the channel. This induces a change in ion concentrations inside the cell, and thereby creates the electrical wave.</p>
<p>Plants make protein channels that are similar to those found in neurons. They also open and close in response to appropriate signals, and, when open, allow ions, especially calcium, to flow. When Salvador-Recatalà and colleagues looked at plants where the function of some of these channels was impaired, they found that caterpillar feeding no long produced electrical waves.</p>
<p>These findings suggest that plants respond to caterpillar nibbling using an electrical signalling network that functions through the same mechanics that neurons rely on. Clearly, plants don’t have neurons, but they make use of similar molecular building blocks to construct a response network.</p>
<p>While aphid spies do have their drawbacks – after all, they are also feeding on the plant – these little parasites are inadvertently providing us with profound insights into how their host plants function. The “wiretapping capabilities” they provide are likely to uncover other secrets encoded in plant responses to a variety of threats, including those of the aphids’ relatives: insect pests.</p><img src="https://counter.theconversation.com/content/25765/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Malcolm Campbell receives funding from the Natural Sciences and Engineering Research Council of Canada, and Genome Canada.</span></em></p>Internal communications in plants share striking similarities with those in animals, new research reveals. With the help of tiny insects, scientists were able to tap into this communication system. Their…Malcolm Campbell, Professor & Vice-Principal Research, University of TorontoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/233902014-02-25T14:49:23Z2014-02-25T14:49:23ZThere may be plant DNA floating in your blood (but that’s OK)<figure><img src="https://images.theconversation.com/files/42459/original/bswbd55y-1393326965.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">All is well with your blood.</span> <span class="attribution"><a class="source" href="http://www.flickr.com/photos/40964293@N07/5460928788/">biologycorner</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>If you believe <a href="http://www.collective-evolution.com/2014/01/09/confirmed-dna-from-genetically-modified-crops-can-be-transfered-to-humans-who-eat-them-2/">this article</a> from Collective Evolution, a site that claims to be “one of the worlds most popular alternative media company”, there is currently DNA from genetically modified plants floating in your blood that must be causing some harm. The conclusion is a wild extrapolation and typical of the anti-GMO lobby, which makes it a good case study for how to treat scientific findings.</p>
<p>The truth is that there may or may not be plant DNA in your blood. The single research paper making this claim, on which the news article is based, is yet to be replicated. But it is more important to note that, even if there is plant DNA in your blood, there is no evidence that it poses a risk to you.</p>
<p>The paper, by Sandor Spisak of Harvard Medical School and colleagues, was published in the journal <a href="http://dx.doi.org/10.1371/journal.pone.0069805">PLOS ONE</a> in July 2013. The authors claimed to have found the evidence that pieces of plant DNA, large enough to harbour full genes, circulate in our blood. </p>
<p>Circulating DNA is called cell-free DNA (cf-DNA) and the reason for its presence in blood and its function, if any, remains a mystery. The science presented by Spisak is peer-reviewed – that is, it has been assessed by experts in the filed – and seems to have been done in an acceptable way. So I am ready to give their case a hearing. </p>
<p>But their study does not imply that consuming GM foods is dangerous or that GM scientists are doing “bad science”, which the news article claims. If foreign DNA from foods we consume circulates in our blood, it must have done so throughout evolutionary history. The fact that we have noticed it only now is interesting. </p>
<p>Before we draw any more conclusions, a lot needs to be done. If cf-DNA’s role hasn’t been clear, then we must investigate that before we can consider what plant DNA might be doing in the blood. </p>
<p>Spisak makes no mention of GM genes in the original paper. My mind is completely put at ease by the thought that DNA from food has always been circulating in our blood.</p>
<p>Here is why: DNA is found in everything you eat. Our body has evolved to breakdown and reuse consumed DNA and the proteins which it encodes. There is no inherent danger in consuming DNA. To label foreign DNA as sinister is wrong. All DNA you consume is foreign unless you’re a cannibal, and even then it’s still foreign unless you’re consuming your identical twin.</p>
<p>Foreign DNA can cause harm only if it is able to encode proteins that are harmful to the human body. For that to happen it would first need to be incorporated into your genome within the cell nucleus where all of your other genes reside. It would then need to be transcribed so that, ultimately, the foreign protein was produced. </p>
<p>So if there is plant DNA in your blood, it will need to jump through lots of hoops before it can produce a foreign protein. There is no evidence by the way that DNA in your blood can do this, because, if cf-DNA has always been in our blood, we would have noticed plant proteins in our cells.</p>
<p>What is really interesting from Spisak’s work is that plant DNA is represented in a relatively high proportion in the cf-DNA pool of human blood. That fact is interesting and worth investigating. Spisak also says that animal DNA was removed from the tested samples because it resembles human DNA too closely and is therefore not distinguishable as “foreign”.</p>
<h2>Good science</h2>
<p>Being “for” GM doesn’t mean that one is against the environment or health and in the pockets of agribusiness as many anti-GMO websites will make you believe. Bryan Walsh writing for <a href="http://science.time.com/2013/05/14/modifying-the-endless-genetically-modified-crop-debate/">Time</a> makes this point clearly. Most scientists are aware that along <a href="http://grist.org/series/panic-free-gmos/">with the promise of GM technology come potential problems</a>. </p>
<p>While GM technology may be able to produce rice that is more nutritious or plants that are resistant to a greener herbicide, there are legitimate problems such as weeds acquiring the GM herbicide resistance. The anti-GM lobby loses credibility by being against every aspect of the science. A better approach would be to act as a watchdog against legitimate, testable problems which science would then be accountable for.</p>
<p>For instance, within days of the publication of Spisak’s paper, Richard Lusk of the University of Michigan left <a href="http://www.plosone.org/annotation/listThread.action?root=69577">a comment</a> where he thought that there could be an alternate explanation for the findings reported. According to Lusk, the method used to analyse cf-DNA, called high-throughput sequencing, has a high-error rate. </p>
<p>Normally, when the DNA to be analysed is plenty and in big chunks, these errors can be minimised. But in Spisak’s case, the analysis involved tiny amounts of DNA, which made Lusk think that contamination, if any, might account for the results. In a follow up study, uploaded few weeks ago on <a href="http://arxiv.org/ftp/arxiv/papers/1401/1401.7975.pdf">arXiv</a>, he concludes that Spisak must consider contamination as the source of plant DNA. Even thoroughly washed plastic equipment can store remnants of DNA that can contaminate results.</p>
<p>It took Lusk six months to thoroughly check Spisak’s work. Now Spisak and his colleagues should respond to Lusk’s criticism, which may take another six months. Scientific progress is slow, but at least at the end of it we may be more certain than we are today. Poor commentary and cherry-picking data helps no one.</p>
<p>Spisak’s study tells us about a significant biological finding that needs to be carefully analysed. The cautionary tale is that one must not extrapolate wildly from good science to create horrific scenarios that are not based on any scientific observations whatsoever.</p><img src="https://counter.theconversation.com/content/23390/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Runions does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>If you believe this article from Collective Evolution, a site that claims to be “one of the worlds most popular alternative media company”, there is currently DNA from genetically modified plants floating…John Runions, Reader in Cell and Molecular Biology, Oxford Brookes UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/189312013-10-07T13:51:06Z2013-10-07T13:51:06ZWe must develop the genetic tools to fight ash dieback<figure><img src="https://images.theconversation.com/files/32502/original/rnkzxsrm-1380903791.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Ash dieback - wilting our leaves since September 2012.</span> <span class="attribution"><span class="source">Gareth Fuller/PA</span></span></figcaption></figure><p>Ashwellthorpe Lower Wood in Norfolk, England has been managed by coppicing, an ancient form of forestry, for more than a thousand years. It was recorded as coppiced woodland in the <a href="http://domesdaymap.co.uk/place/TM1497/ashwellthorpe/">Domesday Book</a> published in 1068 and, as implied from its name, ash trees are a major constitutent species. In fact the name Ashwellthorpe comes from the Vikings, for whom <a href="http://www.viking-mythology.com/yggdrasil.html">Yggdrasil</a>, the giant ash tree, was sacred.</p>
<p>In 1992 the wood was purchased by the <a href="http://www.norfolkwildlifetrust.org.uk">Norfolk Wildlife Trust</a> as a nature reserve and <a href="http://www.sssi.naturalengland.org.uk/Special/sssi/unitlist.cfm?sssi_id=1002849">Site of Special Scientific Interest</a>. Since then the coppice rotation has been managed by local volunteers to maintain the amazing biodiversity there.</p>
<p>So we were devastated when, in September 2012, we realised that many ash trees in the wood were diseased with what we suspected was <a href="http://www.forestry.gov.uk/chalara">ash dieback fungus</a> that had spread from mainland Europe. We tested extracted DNA from the pith of diseased branches, and confirmed the fungal pathogen was present.</p>
<p>Ash dieback had already arrived in the UK in imported trees, but no trees have been planted in Ashwellthorpe, an ancient wood that could have existed since <a href="http://www.bbc.co.uk/nature/ancient_earth/Last_glacial_period">the last Ice Age</a>. This must have been a substantial natural infection, implying that ash trees in Britain will become infected, and that the inexorable spread of the disease from the east to the west of Europe would not been halted by the English Channel. The only questions now are how long the disease will take to establish itself across the country and what proportion of trees will be tolerant to the disease and will survive.</p>
<p>Faced with this scenario, what can be done? European scientists had already established a great deal. The cause of ash dieback was identified in 2006, the fungus named <em>Chalara fraxinea</em>, later realised to actually be a stage of the fungus <em>Hymenoscyphus pseudoalbidus</em>. DNA techniques were established that could confirm the presence of the fungus, and researchers had identified several aspects of its lifecycle, including how the disease is spread by spores fired into the air from small fruiting bodies (mushrooms) that sprout in July and August from rotting leaf stems. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=475&fit=crop&dpr=1 600w, https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=475&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=475&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=597&fit=crop&dpr=1 754w, https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=597&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/32501/original/drzbwnhm-1380903478.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=597&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The ash dieback disease fungal cycle.</span>
<span class="attribution"><span class="source">A Edwards</span></span>
</figcaption>
</figure>
<p>We need to gain more understanding of how the fungal pathogen works. For example, how can we establish laboratory-based tests to discover how it causes the disease? These could be used rapidly to identify resistant trees; they could also be used to establish if and how trees could be inoculated against the disease. For instance species of <em>Trichoderma</em> - ubiquitous, largely harmless fungi found in the soil - have been cultured as biological control agents against some plant fungal diseases.</p>
<p>Establishing and laying out the pathogen’s genome sequence and identifying the genes used for infection can give us real insight into how the disease functions. Those <a href="http://oadb.tsl.ac.uk">working with us</a> have sequenced <em>H. pseudoalbidus</em> using a variety found in Britain. By comparing it with the genes of European varieties, it’s clear that the variation between samples cannot be due to crossbreeding with <em>H. albidus</em>, the closely related, but harmless, fungus usually found on ash leaves.</p>
<p>The key to the long term survival of ash trees lies in the observations of <a href="http://forskning.ku.dk/search/profil/?id=201119">Erik Dahl Kjaer and colleagues</a> in Denmark. Using trees grafted several years ago, they found that one tree, <a href="http://news.jic.ac.uk/2013/03/major-cash-for-ash/">Tree 35</a> out of 39 trees tested, <a href="http://www.bbsrc.ac.uk/news/research-technologies/2013/130617-pr-genome-sequence-for-ash-dieback.aspx">showed tolerance</a> to the fungus in a number of different environments.</p>
<p>This showed that this lower susceptibility to infection is not due to environmental influences, so it must be genetically determined. This means we can breed ash that can withstand the disease. We can be optimistic of some level of genetic resistance among UK ash trees too, and the Department for the Environment, Food and Rural Affairs is undertaking a long-term breeding programme as part of its <a href="http://www.treecouncil.org.uk/tree-wardens/tree-warden-update/item/4100-chalara-plan-published">Chalara Management Plan</a>.</p>
<p>Can we help nature by identifying regions of the ash genome associated with tolerance to the disease? This could be done using genetic crosses with resistant trees, but this would take years. An alternative approach is to try to undertake association genetics. A <a href="http://cshprotocols.cshlp.org/content/2012/3/pdb.top068163.full">recently described</a> modification of association genetics is to identify genetic markers using RNA sequencing, a method <a href="http://www.isb.vt.edu/news/2013/Jan/bancroft.pdf">recently pioneered</a> in crop plants. But genetic approaches require a detailed genetic map, and there is no map for ash or any close relatives yet. Sequencing the ash genome would help greatly in generating a map.</p>
<p>Such a genetic project can provide the tools to help identify the most promising crosses to make between tolerant ash trees. But at this stage nothing is known about whether tolerance is due to one or many genes, whether there are different types of tolerance, whether tolerance is recessive or dominant, or whether combinations of different genes can enhance tolerance. It will take many years to establish, but for those countries facing decimation of their ash forests, it is certainly worth trying.</p><img src="https://counter.theconversation.com/content/18931/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Allan Downie coordinates a programme on ash dieback currently funded jointly by the BBSRC and DEFRA, and has previously had BBSRC and EU funding in other areas. He is an emeritus fellow at the John Innes Centre, funded by the John Innes Foundation.</span></em></p><p class="fine-print"><em><span>Anne Edwards does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Ashwellthorpe Lower Wood in Norfolk, England has been managed by coppicing, an ancient form of forestry, for more than a thousand years. It was recorded as coppiced woodland in the Domesday Book published…Anne Edwards, Research Scientist, John Innes CentreAllan Downie, Department of Molecular Microbiology, John Innes CentreLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/141822013-05-20T12:52:30Z2013-05-20T12:52:30ZHacking plant ‘blood vessels’ could avert food crisis<figure><img src="https://images.theconversation.com/files/24092/original/ngtpvbfh-1368974463.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Leading biologists argue the world must embrace GM plants</span> <span class="attribution"><span class="source">Will de Freitas</span></span></figcaption></figure><p>Today’s wars are not about food, but not too far in the future they could be. The number of people dying of starvation has been falling for decades, but the decline in the numbers of hungry people is slowing down. More than 800 million <a href="http://www.fao.org/hunger/en/">still remain undernourished</a>. With nine billion mouths to feed by 2050, the task of feeding us all is only going to get harder.</p>
<p>There is a solution, though, according to a <a href="http://www.nature.com/nature/journal/v497/n7447/full/nature11909.html">recent paper in the journal Nature </a> written by some of the world’s leading plant biologists. They show that, by hacking how plants transport key nutrients into plant cells, we could solve the impending food crisis.</p>
<p>Each plant is made of billions of cells. All these cells are surrounded by membranes. The pores in these membranes are lined with special chemicals called membrane transporters. They do the job of ferrying nutrients that plants capture from soils with the help of roots.</p>
<p>What scientists have learnt is that if such membrane transporters are tweaked, they can enhance plant productivity. When these tweaks are applied to crops, they can produce plants that are high in calories, rich in certain nutrients or fight pests better. All these methods increase food production while using fewer resources.</p>
<p>Currently, world agriculture faces the problem of shrinking arable land, which is the area that is fit for food production. This is why the world’s leading plant biologists argue in the Nature paper that we must embrace genetically modified (GM) plants, many of which have better membrane transporters making them more productive without increasing land use.</p>
<h2>Good modification</h2>
<p>Over two billion people suffer from iron or zinc deficiency in their diets. Biofortification involves increasing concentration of such essential minerals. Simple genetic modification increases the amount of membrane transporters that ferry these minerals. Such plants when ready for harvest can have as much as <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024476">four times</a> the concentration of iron, compared to that of common crop variety.</p>
<p>A <a href="http://www.ieabioenergy-task38.org/publications/GHG_Emission_Fertilizer%20Production_July2004.pdf">little known fact</a> is that making fertilisers consumes about 2% of world’s energy. This makes the process a significant contributor to emission of greenhouse gases. Modifying membrane transporters can help cut those emissions, because it can make a plant more effective at using plant fertilisers. </p>
<p>For instance, only 20-30% of phosphorus added to soil as fertilisers is used by crop plants. Tweaking transporters such as <a href="http://www.frontiersin.org/plant_traffic_and_transport/10.3389/fpls.2011.00083/abstract">PHT1</a> can increase the uptake of phosphorus. Similar results can be obtained when NRT genes are modified, which increase uptake of nitrogen from fertilisers.</p>
<h2>Better resistance</h2>
<p>About a third of the Earth’s ice-free land is acidic. The problem is that in highly acidic conditions aluminium in soil exists in a form that is toxic to plants. Such land cannot be used to grow food, but if crops were able to counteract the effects of acidity on growth that land would become available. </p>
<p>Scientists have found some varieties of wheat that have a trick to enable them to grow in acidic conditions. One of its membrane transporter called ALMT1 pumps out malate anion from its roots into the soil which traps the toxic form of aluminium. </p>
<p>Varieties of wheat without this natural transporter can be improved by breeding with varieties that do. But, crops such as barley, which have no comparable system of transporter in its membrane, need to be genetically modified to express the ALMT1 transporter protein. This allows for greatly <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1467-7652.2009.00403.x/abstract">increased yields</a> even in acidic soils.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/24142/original/gmbp69dh-1369048466.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Not doing evil. Instead trying to find ways to avert evil.</span>
<span class="attribution"><span class="source">IRRI Images</span></span>
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<h2>When salt is bad</h2>
<p>Much of the world’s arable lands are becoming salty as a result of current irrigation practices. This happens when, on evaporation, salts in irrigation water are left behind inthe soil. Salts are toxic to plants and are severely limiting yields in over 30% of irrigated crops. </p>
<p>But there are membrane transporters which can stem the flow of salts into plants. These transporters, from the HKT family, rid the water of sodium before it is taken up by the plants. One example is that of durham wheat, which was modified to possess the HKT5 gene. The modification helped <a href="http://www.csiro.au/en/Organisation-Structure/Divisions/Plant-Industry/Acid-and-salinity-tolerant-plants.aspx">increase its yield</a> in salty soils by 25%.</p>
<h2>Fighting from the inside</h2>
<p>Disease-causing micro-organisms, pathogens, manipulate a plant’s functioning and consume the fruit of its labour. Most crops have membrane transporters called SWEETs that move sucrose made by leaves from photosynthesis to other regions where it may be stored. Plant pathogens have evolved to manipulate SWEET genes so that sugars are moved to cells where they can feed on the goods.</p>
<p>Now scientists have found a way of disrupting this pathogen-induced manipulation by a method called <a href="http://www.nature.com/nature/journal/v457/n7228/full/457395a.html">RNA-silencing</a>. These reduce, or sometimes eliminate, the pathogens’ ability to feed on the plants’ hard work, and in turn they help increase plant productivity.</p>
<h2>Not all bad</h2>
<p>Researchers have been quietly chugging away in labs working on making such radical improvements to crops. Breeding of plants, a form of untailored genetic modification that bestowed most of the benefits to agriculture a generation ago, is not able to keep up with the pace of change required for an ever-increasing demand for food. That is why it is important that we understand the science behind the process of tinkering with specific genes, before jumping on the “GM is bad” wagon. </p>
<p>Scientists are aware of the moral, ethical and environmental discussions surrounding production of GM food, and have been <a href="http://www.senseaboutscience.org/resources.php/9/making-sense-of-gm">working carefully to address those issues</a>. It is important that they continue to do so, while exploring the full potential of GM research to tackle the issue of hunger that looms large over the future of our species.</p><img src="https://counter.theconversation.com/content/14182/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>John Runions receives funding from BBSRC and Leverhulme Trust to conduct research in plant cell biology.</span></em></p>Today’s wars are not about food, but not too far in the future they could be. The number of people dying of starvation has been falling for decades, but the decline in the numbers of hungry people is slowing…John Runions, Reader in Cell and Molecular Biology, Oxford Brookes UniversityLicensed as Creative Commons – attribution, no derivatives.