tag:theconversation.com,2011:/us/topics/tomato-956/articlesTomato – The Conversation2022-11-21T16:03:58Ztag:theconversation.com,2011:article/1941072022-11-21T16:03:58Z2022-11-21T16:03:58ZThe story of the purple tomato — and why its success is a win for GM foods<figure><img src="https://images.theconversation.com/files/496133/original/file-20221118-14-vcxy21.jpg?ixlib=rb-1.1.0&rect=11%2C0%2C7337%2C4912&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Purple tomatoes have been approved for sale in the US.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/192935490@N06/51158519805/in/album-72157719094266799/">JIC Photography/ flickr</a></span></figcaption></figure><p>The first genetically modified (GM) food ever made commercially available to the public was a tomato, invented in the US in 1994. Since then, a number of different genetically modified foods have been created, including corn, cotton, potatoes and pink pineapple. </p>
<p>Although genetically modified foods still get a bit of a bad rap, there are actually many good reasons why modifying an organism’s genetics may be worthwhile. For example, many breeds of genetically modified foods have made them <a href="https://www.fda.gov/food/agricultural-biotechnology/gmo-crops-animal-food-and-beyond">more resistant to disease</a>. </p>
<p>It’s also possible to modify foods to <a href="https://www.fda.gov/food/agricultural-biotechnology/gmo-crops-animal-food-and-beyond">make them more nutritious</a>. Take for example golden rice. This grain was engineered to have higher levels of vitamin A, in order to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682994/">tackle deficiencies of this nutrient</a> in impoverished countries. </p>
<p>But despite all the developments in genetically modified foods since 1994, few products have actually made it to the market. The <a href="https://theconversation.com/revealed-why-gm-food-is-so-hard-to-sell-to-a-wary-public-43864">continued ignorance of the general public</a> about GM products alongside the reluctance of government policymakers in some countries have impeded the progress of genetically modified foods moving from the lab to the market. This is why the <a href="https://www.aphis.usda.gov/aphis/newsroom/stakeholder-info/sa_by_date/sa-2022/purple-tomato">regulatory approval</a> of purple tomatoes in the US this September is so exciting. </p>
<h2>Making a purple tomato</h2>
<p>For the last 14 years, <a href="https://www.jic.ac.uk/people/cathie-martin/">Cathie Martin</a> and <a href="https://www.jic.ac.uk/people/eugenio-butelli/">Eugenio Butelli</a> from the John Innes Centre in Norfolk, England, and their team have been working on developing the purple tomato. Their aim was to engineer a tomato that contained higher levels of anthocyanins – which can be used alongside unmodified tomatoes to study the benefits of anthocyanins. The team chose to modify a tomato because the fruits are delicious and widely consumed.</p>
<p>Anthocyanins occur naturally in many fruits and vegetables that have a red, purple or blue flesh or peel – such as blueberries, strawberries, aubergines and red cabbages. In order to produce a purple tomato, the team <a href="https://www.nature.com/articles/nbt.1506">incorporated genes</a> from snapdragons into the DNA of tomatoes.</p>
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<img alt="A basket of blueberries." src="https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=468&fit=crop&dpr=1 754w, https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=468&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/496134/original/file-20221118-24-psgdmc.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=468&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">Purple tomatoes contain the same level of anthocyanins as blueberries.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/blueberries-basket-662033851">pilipphoto/ Shutterstock</a></span>
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<p>The end result of these experiments was a unique fruit – and not just because of it’s colour. They also succeeded in engineering tomatoes that contained high levels of anthocyanins – comparable to the amount found in blueberries – which is beneficial for a number of reasons.</p>
<p>The higher levels of anthocyanins in purple tomatoes actually work to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3688073/">double their shelf life</a> compared to red tomatoes. This is because anthocyanins help to delay over-ripening and reduce the fruit’s susceptibility to fungus attack post-harvest.</p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S1369526614000673?via%3Dihub">Another benefit</a> of high levels of anthocyanins is that they attract pollinators and animals to disperse seeds, which increases reproductive success of the plants and their yield. Anthocyanins also protect plants from <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7024295/">UV damage</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0960982213005137">protect them from pathogens</a>, which maximises their survival. </p>
<p>Anthocyanins may also be good for your health. Studies on other foods containing them have linked them to lower inflammation, lower risk of type 2 diabetes and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613902/#:%7E:text=Anthocyanins%20possess%20antidiabetic%2C%20anticancer%2C%20anti,plants%20are%20potential%20pharmaceutical%20ingredients.">cancer</a>. They may also <a href="https://pubmed.ncbi.nlm.nih.gov/33212797/#:%7E:text=Anthocyanins%20exhibit%20a%20significan">protect the brain</a> against disease, such as dementia. </p>
<p>While studies into the benefits of purple tomatoes specifically on humans are still ongoing, one study which fed cancer-prone mice food supplemented with purple tomatoes found they actually <a href="https://www.nature.com/articles/nbt.1506">lived 30% longer</a> compared to the mice given red tomatoes. </p>
<h2>The future of GM</h2>
<p>There have been a number of exciting developments in the field of GM foods in the last few years, including the first <a href="https://www.nature.com/articles/s41598-017-06400-y">genome-edited GABA tomatoes</a> in Japan and <a href="https://www.nature.com/articles/s41477-022-01154-6">vitamin D enriched tomatoes</a> in the UK. Both were developed using <a href="https://www.annualreviews.org/doi/abs/10.1146/annurev-arplant-050718-100049">CRISPR genome-editing technology</a>. </p>
<p>Genetic modification can offer many benefits. Not only might it help us tackle the challenges of climate change by developing <a href="https://www.tsl.ac.uk/news/gm-spuds-beat-blight">more resilient crops</a>, breeding plants with higher levels of certain <a href="https://www.frontiersin.org/articles/10.3389/fpls.2020.577313/full">vitamins and minerals</a> may potentially allow us to improve health and lower the burden of many common diseases. And, GM crops may help us ensure that everyone, regardless of where they live, has access to high-quality fresh produce that’s good for them and the environment. </p>
<p>GM foods are also <a href="https://www.fda.gov/food/agricultural-biotechnology/how-gmos-are-regulated-united-states">tightly regulated</a> in many countries, which means that any products which are <a href="https://www.gov.uk/government/collections/genetically-modified-organisms-applications-and-consents">approved for consumption</a> are safe for human, plant and animal health. </p>
<p>The greatest challenge now is getting more governments around the world to approve these genetically modified foods for sale. Although the UK is ahead of other countries when it comes to <a href="https://www.gov.uk/government/news/new-powers-granted-to-research-gene-editing-in-plants">regulation of gene-edited crops</a>, it’s currently unknown whether the GM purple tomato will be offered for sale there. But it’s expected that purple tomatoes will be available for sale in the US <a href="https://edition.cnn.com/2022/09/17/business-food/purple-tomato-gmo-scn-trnd/index.html">as soon as 2023</a>.</p><img src="https://counter.theconversation.com/content/194107/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yang Yue 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 US recently approved the genetically modified fruit, which has enhanced nutritional qualities.Yang Yue, PhD Candidate in Plants, Food and Health, Quadram InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1572352022-01-04T19:13:15Z2022-01-04T19:13:15Z4 plant-based foods to eat every week (and why science suggests they’re good for you)<figure><img src="https://images.theconversation.com/files/436253/original/file-20211208-140109-1hurlbt.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C4500%2C2997&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>As a laureate professor in nutrition and dietetics people often ask – what do you eat? </p>
<p>Plant-based foods are good sources of healthy nutrients. These include different types of dietary fibre, vitamins, minerals, and a range of “<a href="https://theconversation.com/phytonutrients-can-boost-your-health-here-are-4-and-where-to-find-them-including-in-your-next-cup-of-coffee-132100">phytonutrients</a>”, which plants produce to help them grow or protect them from pathogens and pests.</p>
<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/33951994/">review of research published in May 2021</a> looked at 12 studies with more than 500,000 people who were followed for up to 25 years. It found those who ate the most plant foods were less likely to die from any cause over follow-up time periods that varied across the studies from five to 25 years, compared to those who ate the least.</p>
<p>Here are four versatile and tasty plant foods I have on my weekly grocery list, and the research showing why they’re good for you.</p>
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Read more:
<a href="https://theconversation.com/plant-rich-diets-may-help-prevent-depression-new-evidence-103898">Plant-rich diets may help prevent depression – new evidence</a>
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<h2>1. Tomatoes</h2>
<p>Tomatoes are a berry fruit (not a vegetable). They’re rich in vitamin C and “<a href="https://en.wikipedia.org/wiki/Lycopene">lycopene</a>”, which is a carotenoid. Carotenoids are pigments produced by plants and give vegetables their bright colours. </p>
<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/32243013/">review of six trials</a> asked people to consume tomato products equivalent to 1-1.5 large tomatoes or 1-1.5 cups of tomato juice daily for about six weeks.</p>
<p>The researchers found people who did this had reduced blood levels of triglycerides (a type of fat in your blood that <a href="https://pubmed.ncbi.nlm.nih.gov/31530008/">increases heart disease risk</a>), as well as lower total and “bad” cholesterol levels, compared to those who didn’t have any tomatoes.</p>
<p>These people also had increased levels of “good cholesterol”.</p>
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Read more:
<a href="https://theconversation.com/love-meat-too-much-to-be-vegetarian-go-flexitarian-73741">Love meat too much to be vegetarian? Go 'flexitarian'</a>
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<p>Another review of 11 studies tested the <a href="https://pubmed.ncbi.nlm.nih.gov/33676812/">effect of tomatoes and lycopene on blood pressure</a>.</p>
<p>Researchers found consuming any tomato products led to a large decrease in systolic blood pressure (the first number that measures the pressure at which the heart pumps blood).</p>
<p>However, there was no effect on the diastolic pressure (the second number which is the pressure in the heart when it relaxes).</p>
<p>In the group who had high blood pressure to begin with, both systolic and diastolic blood pressure decreased after eating tomato products compared to placebos.</p>
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<img alt="Tomatoes" src="https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/435741/original/file-20211206-25-1dfc2id.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">
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<span class="caption">Tomatoes are high in vitamin C and other important healthy nutrients.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/29317772/">review of studies</a> included a total of 260,000 men and found those with the highest intakes of cooked tomatoes, tomato sauces and tomato-based foods (equivalent to around one cup per week) had a 15-20% lower risk of developing prostate cancer compared to those with the lowest tomato intakes. Keep in mind correlation doesn’t necessarily mean causation, though. </p>
<p><strong>Recipe tips</strong></p>
<p>Keep canned tomatoes in the cupboard and add to pasta sauce, casseroles and soup. Make your own sauce by roasting tomatoes and red capsicum with a splash of olive oil and balsamic vinegar, then puree with a spoon of chilli paste or herbs of your choice. Keep in the fridge.</p>
<p>Try our fast tomato <a href="https://nomoneynotime.com.au/healthy-easy-recipes/filter/keywords--tomato">recipes at No Money No Time</a>, a site full of dietary advice and recipes founded by my team at the University of Newcastle. </p>
<h2>2. Pumpkin</h2>
<p>Pumpkin is rich in beta-carotene, which is also a carotenoid (plant pigment). It gets converted into vitamin A in the body and <a href="https://pubmed.ncbi.nlm.nih.gov/24782580/">is used in the production of antibodies that fight infection</a>. It’s also needed to maintain the integrity of cells in eyes, skin, lungs and the gut. </p>
<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/30475962/">review of studies that followed people over time</a> looked at associations between what people ate, blood concentrations of <a href="https://en.wikipedia.org/wiki/Beta-Carotene">beta-carotene</a> and health outcomes.</p>
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Read more:
<a href="https://theconversation.com/carrots-and-pumpkin-might-reduce-your-risk-of-cancer-but-beware-taking-them-in-pill-form-75537">Carrots and pumpkin might reduce your risk of cancer, but beware taking them in pill form</a>
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<p>People who had the highest intakes of foods rich in beta-carotene (such as pumpkin, carrots, sweet potato and leafy greens) had an 8-19% lower relative risk of having coronary heart disease, stroke, or dying from any cause in studies over 10 years or more compared to those with the lowest intakes.</p>
<p><strong>Recipe tips</strong></p>
<p>Pumpkin soup is a favourite. Try our <a href="https://nomoneynotime.com.au/healthy-easy-recipes/design-your-own-pumpkin-soup">design-your-own</a> soup recipe.</p>
<p>Heat oven to 180°C, chop the pumpkin into wedges, drizzle with olive oil, roast till golden. Speed it up by microwaving cut pumpkin for a couple of minutes before roasting.</p>
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<img alt="Carrots, pumpkins, sweet potato and other vegetables" src="https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=420&fit=crop&dpr=1 600w, https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=420&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=420&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=528&fit=crop&dpr=1 754w, https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=528&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/435743/original/file-20211206-27-12a8ug6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=528&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">Pumpkins, carrots and sweet potato have high levels of beta-carotene, which has health benefits.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>3. Mushrooms</h2>
<p>Mushrooms are rich in nutrients with strong antioxidant properties.</p>
<p>The body’s usual processes create <a href="https://www.betterhealth.vic.gov.au/health/healthyliving/antioxidants">oxidative stress</a>, which generates “free radicals”. These are small particles that damage cells walls and cause the cells to die.</p>
<p>If these aren’t neutralised by antioxidants, they can trigger inflammation, contribute to ageing and development of some cancers. </p>
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Read more:
<a href="https://theconversation.com/what-are-antioxidants-and-are-they-truly-good-for-us-86062">What are antioxidants? And are they truly good for us?</a>
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<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/33724299/">review of 17 studies on mushrooms and health</a> found people who ate the most mushrooms had a 34% lower risk of developing any type of cancer compared to those with lowest intakes. For breast cancer, the risk was 35% lower. Though, again, correlation doesn’t necessarily mean causation.</p>
<p>Across the studies, a high mushroom intake was equivalent to eating a button mushroom a day (roughly 18 grams).</p>
<p><strong>Recipe tips</strong></p>
<p>Check out our <a href="https://nomoneynotime.com.au/healthy-easy-recipes/basic-mushroom-baby-spinach-side">mushroom and baby spinach stir-fry recipe</a>. It makes a tasty side dish to serve with scrambled or poached eggs on toast. </p>
<h2>4. Oats</h2>
<p>A <a href="https://pubmed.ncbi.nlm.nih.gov/33296453/">review of ten studies</a> tested the effects on blood sugar and insulin levels from eating intact oat kernels, thick rolled oats or quick rolled oats compared to refined grains.</p>
<p>These found eating intact oat kernels and thick rolled oats led to significant reductions in blood glucose and insulin responses, but not after eating quick rolled oats.</p>
<p>This is likely due to the longer time it takes for your body to digest and absorb the less-processed oats. So it’s better to eat whole grain oats, called groats, or rolled oats rather then quick rolled oats.</p>
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<strong>
Read more:
<a href="https://theconversation.com/phytonutrients-can-boost-your-health-here-are-4-and-where-to-find-them-including-in-your-next-cup-of-coffee-132100">Phytonutrients can boost your health. Here are 4 and where to find them (including in your next cup of coffee)</a>
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<p>Oats are a good sources of <a href="https://pubmed.ncbi.nlm.nih.gov/34828872/">beta-glucan</a>, a soluble fibre shown to help lower blood cholesterol levels.</p>
<p>Across <a href="https://pubmed.ncbi.nlm.nih.gov/27724985/">58 studies where people were fed a special diet</a> containing about 3.5 grams of oat beta-glucan a day, “bad” cholesterol levels were significantly lower compared with control groups.</p>
<p>The impact of oats <a href="https://pubmed.ncbi.nlm.nih.gov/25668347/">on blood pressure has been tested in five intervention trials</a> which showed a small, but important, drop in blood pressure.</p>
<p><strong>Recipe tips</strong></p>
<p>You can eat rolled oats for breakfast year round.</p>
<p>Eat them as <a href="https://nomoneynotime.com.au/healthy-easy-recipes/filter/keywords--oats">muesli in summer or porridge in winter</a>, add to meat patties, mix with breadcrumbs for coatings or add to fruit crumble toppings.</p><img src="https://counter.theconversation.com/content/157235/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Clare Collins is affiliated with the Priority Research Centre for Physical Activity and Nutrition, the University of Newcastle, NSW. She has received research grants from NHMRC, ARC, MRFF, Hunter Medical Research Institute, Diabetes Australia, Heart Foundation, Bill and Melinda Gates Foundation, nib foundation, Rijk Zwaan Australia, WA Dept. Health, Meat and Livestock Australia, and Greater Charitable Foundation. She has consulted to SHINE Australia, Novo Nordisk, Quality Bakers, the Sax Institute and the ABC. She was a team member conducting systematic reviews to inform the Australian Dietary Guidelines update and the Heart Foundation evidence reviews on meat and dietary patterns.</span></em></p>As a laureate professor in nutrition and dietetics, people often ask me what I eat. Here are four plant-based foods I have on my weekly grocery list.Clare Collins, Laureate Professor in Nutrition and Dietetics, University of NewcastleLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1313672020-04-07T12:04:48Z2020-04-07T12:04:48ZCrops could face double trouble from insects and a warming climate<figure><img src="https://images.theconversation.com/files/321744/original/file-20200319-22636-y9mufw.jpg?ixlib=rb-1.1.0&rect=90%2C49%2C5021%2C3006&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">In the heat, tomato plants can't fight off the hungry tobacco hornworm, Manduca sexta. </span> <span class="attribution"><span class="source">From www.shutterstock.com</span></span></figcaption></figure><p>For millennia, insects and the plants they feed on have been engaged in a co-evolutionary battle: to eat or not be eaten. Until recently, the two antagonistic sides have maintained a stalemate of sorts. With climate change, however, warmer temperatures could tip the balance in favor of the insects and spell danger for crops and the farmers that tend to them. </p>
<p>Our research team at Michigan State University’s <a href="https://plantresilience.msu.edu/">Plant Resilience Institute</a> watched what happened in hotter weather when <a href="https://doi.org/10.1073/pnas.1913885117">hornworm caterpillars attacked a tomato plant</a>. The tomato lost. We saw a surprising trade-off by the plant during the heat wave: It defended itself against the caterpillars but this effort prevented it from dealing with the harmful effects of heat. This caused the plant to overheat, which strengthened the caterpillars’ hand.</p>
<p>A study by researchers in 2018 predicted that each degree of global warming will <a href="http://dx.doi.org/%2010.1126/science.aat3466">increase crop loss from insects by 10% to 25%</a> because insect populations and their appetites surge in warm temperatures. Other climate-related variables, including prolonged droughts or floods, are likely to compound those losses.</p>
<p>But although scientists have identified these varied challenges to food production, they still don’t know much about how the combination of heat and insects will affect the plants’ built-in defense systems. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/gha8eF5xk4I?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Plants constantly sense and respond to changes in their environments, including the presence of plant-eating insects.</span></figcaption>
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<h2>How plants fight off insect pests</h2>
<p>Unlike animals, plants cannot run or hide from predators. Instead, plants produce an arsenal of toxic chemicals that repel attack by insects and other plant consumers. </p>
<p>Producing these compounds is costly and often stunts their growth, so plants deploy this chemical defense arsenal only when damaged by a chewing insect. This process is triggered by the plant wound hormone, jasmonate, which tightly controls the biosynthesis, distribution and storage of chemical defense compounds that repel insects.</p>
<p>For more than 20 years, we have studied how jasmonate <a href="https://scholar.google.com/citations?user=XeUeJkkAAAAJ&hl=en">protects plants</a> from insect herbivores. Only recently have we begun to think about how rising global temperatures influence this common plant defense mechanism.</p>
<h2>Heat and the hungry caterpillar</h2>
<p>In our study we <a href="https://doi.org/10.1073/pnas.1913885117">challenged tomato plants</a> with hornworm caterpillars under either normal temperature conditions: 82 degree F days (about 28 degrees C) and 64 degree F nights (about 18 degrees C). We also simulated heat waves, with temperatures rising to 100 F (38 C) in the daytime and falling to 82 F (28 C) at night for several days.</p>
<p>The plants responded to the hotter temperatures by intensifying production of jasmonate and, as a consequence, increasing the output of various defense compounds. Even so, insects ate the plants relentlessly in the heat. </p>
<p>Meanwhile, a parallel study by our team found that moderate increases in temperature <a href="https://doi.org/10.3390/plants9020172">speeded up the insects’ metabolism</a> so that they ate faster and did more damage to the plants. Although tomato plants fought hard with their chemical response, they couldn’t neutralize the insects’ powerful heat-triggered eating stimulus. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/zYdbbZIEwkE?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Models may underestimate crop losses due to climate change because they don’t consider how infested plants react to rising temperatures.</span></figcaption>
</figure>
<h2>Insects + heat = double trouble</h2>
<p>Plants use two strategies to cool down when temperatures get too high. They will open their tiny leaf pores, which are called stomata, releasing water that cools them much as sweating cools humans. Plants also combat heat stress by lifting their leaves away from the hot soil, perhaps in search of a cool breeze. </p>
<p>We unexpectedly discovered in our work that tomato plants challenged by caterpillars at the warmer temperature didn’t do these things, and thus failed to cool their leaves.</p>
<p>In our follow-up experiments, we found that when caterpillars ate its leaves and the plant activated the hormone jasmonate, this blocked the opening of the tiny stomata, and also prevented leaves from lifting up to cool. The plant couldn’t deploy its cooling response, and at the same time photosynthesis (making food from sunlight and carbon dioxide) was reduced. </p>
<p>These circumstances effectively slow the growth of the plant. Thus, although tomato plants can cope well with insect attacks or elevated temperature, if those two stresses come at the same time, that spells double trouble. The result is rapid defoliation by hungry caterpillars plus leaf overheating.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1004284554679422976"}"></div></p>
<h2>Studying plants in real environments</h2>
<p>Why insect attack keeps the plants from cooling themselves remains a mystery. However, when plants close their stomata during an insect attack, they conserve water by preventing it from evaporating from wounded leaves. We think this response may benefit the plant when water is in short supply, which is often the case during heat waves. </p>
<p>We plan to address this question by studying plants grown in the rough-and-tumble of natural environments, rather than under highly controlled laboratory conditions. We believe such studies are necessary to develop crops that can withstand both heat and wound stress.</p>
<h2>Making more resilient plants</h2>
<p>Many experts estimate that agricultural productivity must double in the next 30 years to meet the demands of a <a href="https://doi.org/10.1038/ncomms2296">rapidly growing population</a>. Current yield trajectories for major crops, combined with the uncertain impacts of a changing global environment, suggest that the world will fall well short of this demand using conventional agricultural practices. </p>
<p>The United Kingdom’s <a href="https://royalsociety.org/">Royal Society</a> and other scientific organizations have called for a <a href="https://royalsociety.org/%7E/media/Royal_Society_Content/policy/publications/2009/4294967719.pdf">Second Green Revolution</a> that will permit the sustainable intensification of agriculture through development of crops that are more resilient in face of increasingly harsh environmental conditions. </p>
<p>Recent technological advances, from genomics and gene editing to computational and data science approaches, provide researchers with unprecedented opportunities to work toward this goal. In achieving a better understanding of the complex interactions of heat and insect attacks, we hope that our research may inform new strategies to increase plant resilience in a warming world.</p>
<p>[<em>Get the best of The Conversation, every weekend.</em> <a href="https://theconversation.com/us/newsletters/weekly-highlights-61?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=weeklybest">Sign up for our weekly newsletter</a>.]</p><img src="https://counter.theconversation.com/content/131367/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Funding for this research was provided to Gregg Howe by the Plant Resilience Institute at Michigan State University. </span></em></p><p class="fine-print"><em><span>Nathan Havko receives funding from the Michigan State University Plant Resilience Institute</span></em></p>Plants have evolved techniques for protecting themselves from heat and insect attacks – but when both these stresses happen at once, one defense may neutralize the other.Gregg Howe, Professor of Biochemistry and Molecular Biology, Michigan State UniversityNathan Havko, Postdoctoral Fellow in Plant Research, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1300412020-01-30T13:13:31Z2020-01-30T13:13:31ZModern tomatoes are very different from their wild ancestors – and we found missing links in their evolution<figure><img src="https://images.theconversation.com/files/312304/original/file-20200128-81416-1odt8n2.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5000%2C2971&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tomatoes' ancestors looked very different.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/flatlay-fresh-colorful-ripe-fall-summer-1124959727"> Foxys Forest Manufacture/Shutterstock</a></span></figcaption></figure><p><em>The Research Brief is a short take on interesting academic work.</em></p>
<p><strong>The Big Idea:</strong> The tomato’s path from wild plant to household staple is much more complex than researchers have long thought. For many years, scientists believed that humans domesticated the tomato in two major phases. First, native people in South America cultivated blueberry-sized wild tomatoes about 7,000 years ago to breed a plant with a cherry-sized fruit. Later, people in <a href="https://en.wikipedia.org/wiki/Mesoamerica">Mesoamerica</a> bred this intermediate group further to form the large cultivated tomatoes that we eat today. </p>
<p>But in a 2020 study, we show that the cherry-sized tomato likely <a href="https://doi.org/10.1093/molbev/msz297">originated in Ecuador around 80,000 years ago</a>. No human groups were domesticating plants that long ago, so this implies that it started as a wild species, although people in Peru and Ecuador probably cultivated it later. </p>
<p>We also found that two subgroups from this intermediate group spread northward to Central America and Mexico, possibly as weedy companions to other crops. As this happened, their fruit traits changed radically. They came to look more like wild plants, with smaller fruits than their South American counterparts and higher levels of citric acid and beta carotene. </p>
<p>We were surprised to find that modern cultivated tomatoes seem most closely related to this wild-like tomato group, which is still found in Mexico, although farmers don’t deliberately cultivate it. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=109&fit=crop&dpr=1 600w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=109&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=109&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=137&fit=crop&dpr=1 754w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=137&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/312295/original/file-20200128-81341-1aqkfhm.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=137&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Average fruit size in the cultivated tomato in comparison with its semi-domesticated and fully wild relatives.</span>
<span class="attribution"><span class="source">Hamid Razifard</span>, <a class="license" href="http://creativecommons.org/licenses/by-nd/4.0/">CC BY-ND</a></span>
</figcaption>
</figure>
<p><strong>Why it matters:</strong> This research has direct implications for crop improvement. For example, some intermediate tomato groups have high levels of glucose, which makes the fruit sweeter. Breeders could use those plants to make cultivated tomatoes more attractive to consumers. </p>
<p>We also saw signals that some varieties in this intermediate group had traits that promoted disease resistance and drought tolerance. Those plants could be used to breed hardier tomatoes.</p>
<p><strong>What still isn’t known:</strong> We don’t know how the intermediate group of tomatoes spread from South America to Central America and Mexico. Birds may have eaten the fruits and excreted the seeds elsewhere, or humans may have cultivated or traded them.</p>
<p>Another question is why this intermediate group “regressed” and lost so many domestication traits once it spread north. Natural selection in new northern habitats may have actively favored tomatoes with more wild-like traits. It also could be that humans weren’t breeding these plants and selecting for domestication traits, such as large fruits, which may require plants to use more energy than they would put into fruiting naturally.</p>
<p><strong>How we do our work:</strong> We <a href="https://scholar.google.com/citations?user=tNvKhWwAAAAJ&hl=en">reconstruct tomato history</a> by <a href="https://scholar.google.com/citations?user=E_vnipYAAAAJ&hl=en">sequencing the genomes</a> of wild, intermediate and domesticated tomato varieties. We also carry out population genomic analyses, in which we use models and statistics to deduce the changes that have occurred to tomatoes over time.</p>
<p>This work involves writing a lot of computer codes to analyze large amounts of data and look at patterns of variation in DNA sequences. We also work with other scientists to grow tomato samples and record data on many traits, such as fruit size, sugar content, acid content and flavor compounds. </p>
<p><strong>What else is happening in the field:</strong> Feeding a growing human population will require improving crop yields and quality. To do this, scientists need to know more about plant genes that are involved in phenomena such as fruit development and flavor and disease resistance. </p>
<p>For example, research led by <a href="http://lippmanlab.labsites.cshl.edu/people/">Zachary Lippman</a> at the <a href="https://www.cshl.edu/">Cold Spring Harbor Laboratory</a> in New York is using genome editing to manipulate traits that can help improve tomato yield. By tweaking genes native to two popular varieties of tomato plants, they have devised a rapid method to make the plants flower and produce ripe fruit more quickly. This means more plantings per growing season, which increases yield. It also means that the plant can be grown in latitudes more northerly than currently possible – an important attribute as the Earth’s climate warms.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Jem3hP734uA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Gene editing has produced tomatoes that flower and ripen weeks earlier.</span></figcaption>
</figure>
<p><strong>What’s next for you:</strong> Our research provides an atlas of candidates for future tomato gene function studies. We now can identify which genes were important at each stage of domestication history, and discover what they do. We also can search for beneficial alleles, or variants of specific genes, that may have been lost or diminished as the tomato was domesticated. We want to find out whether some of those lost variants could be used to improve growth and desirable traits in cultivated tomatoes.</p><img src="https://counter.theconversation.com/content/130041/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hamid Razifard receives funding from National Science Foundation of USA. </span></em></p><p class="fine-print"><em><span>Ana Caicedo receives funding from the National Science Foundation (NSF) of the USA and the National Institute of Food and Agriculture (NIFA) of the USA. </span></em></p>Through genetic detective work, scientists have identified missing links in the tomato’s evolution from a wild blueberry-sized fruit in South America to the larger modern tomato of today.Hamid Razifard, Postdoctoral Researcher in Biology, UMass AmherstAna Caicedo, Associate Professor of Biology, UMass AmherstLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1243742019-10-07T12:39:26Z2019-10-07T12:39:26ZGrowing the big one – 6 tips for your own prize-winning tomatoes<figure><img src="https://images.theconversation.com/files/295316/original/file-20191002-49356-1v3q5ik.jpg?ixlib=rb-1.1.0&rect=37%2C104%2C2678%2C1978&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Bigger, bigger, biggest.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/huge-pleated-red-ripe-heirloom-tomato-1179875506">TheOldBarnDoor/Shutterstock.com</a></span></figcaption></figure><p>When I answer my office phone as an extension vegetable specialist, from time to time it’s someone asking how they can get recognition for growing a huge tomato, possibly the biggest one ever. When I ask how big a tomato we’re talking about, and the caller says 2 or 2.5 pounds, I have to hold back my laughter and gently explain that that is nowhere even close to a record. </p>
<p>So just how big is big? Growers in various states have set various records – New Jersey was home to a <a href="https://www.njtomato.com/main.htm">6-pound, 2.5-ounce tomato</a>, Oklahoma has boasted a 7-pound, 12-ounce one and Minnesota <a href="https://www.worldrecordacademy.com/nature/heaviest_tomato_Dan_MacCoy_breaks_Guinness_World_Records_record_214064.html">weighed in at 8 pounds, 6 ounces</a>. According to the Guinness Book of World Records, Dan Sutherland of Walla Walla, Washington is the current tomato king, having produced a tomato <a href="https://www.guinnessworldrecords.com/world-records/heaviest-tomato">tipping the scale at 8 pounds, 9 ounces</a> in 2016.</p>
<p>If you take that as a challenge to your own tomato-growing prowess, read on for tips on how to nurture a massive tomato. The secrets are really nothing too obscure. What’s important is checking off as many boxes as possible to optimize the fruit size. <a href="http://extension.msstate.edu/publications/tomato-troubles-common-problems-tomatoes">Each step is attainable</a> for the home gardener, but missing out on certain ones will limit your results.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/bHcmVcIJjB0?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Dan MacCoy shows off his 8.41-pound tomato in 2014.</span></figcaption>
</figure>
<h2>Pick a proven pedigree</h2>
<p>Are some varieties better for fruit size? Absolutely. The best way to determine which ones to use is to look at previous winners. Genes are important. </p>
<p>A cherry, grape or plum tomato plant isn’t going to yield a winner. Some varieties have a genetic potential to produce larger fruit than others, including Beefsteak, Delicious, Big Beef, Big Rainbow, Dinner Plate, Giant Belgium, Big Pink, German Johnson, T & T Monster, Braggar and Brandywine, among others. All of these big boys are in the category of beefsteak tomato – they have smaller seed cavities than other varieties, and so proportionally more flesh than juice and seeds.</p>
<p>Since it would be hard to find plants of most of these at your local garden center, you will likely have to order seeds from seed catalogs and start your own plants.</p>
<p>There’s no guarantee that a plant of one of these varieties will be a winner. Although the potential for large size is in the genes, it will not be achieved unless the environmental conditions are optimized. And by that, I mean perfect.</p>
<h2>Super soil</h2>
<p>One of the most important tips is to start with great soil. All plants, not just tomatoes, will do much better if planted in <a href="http://extension.msstate.edu/vegetable-gardening-mississippi/garden-soil">properly prepared soil</a>. The soil should be well drained, high in organic matter and fertile. </p>
<p>Tomatoes thrive on animal manures. So if you have access to some composted (not fresh) manure, you might place some in the bottom of the hole and then cover it up before transplanting your seedling. This is a tried and true method for lots of old-time tomato growers.</p>
<h2>A place in the sun</h2>
<p>Like most vegetables, tomatoes need full sun. Anything less will decrease maximum photosynthesis, thereby limiting growth of foliage and fruit. A tomato plant needs lots of leaves to catch as much sun as possible, manufacture sugars and send those sugars to the developing fruit. They also don’t mind the heat (up to a point), so long as there is plenty of water in the root zone to keep them from drying out. </p>
<p>When the temperature gets into the mid 90s or above, that’s when trouble can occur. Tomato pollen is sterilized at 94 degrees Fahrenheit, so even if pollination occurs and pollen makes it from the male to the female parts of the flower, there won’t be much fertilization since pollen has been killed. So higher temperatures limit fruit set: the transformation of flower into fruit. Fruit quality and size will also suffer at very high temperature.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/295318/original/file-20191002-49356-uhr6g2.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">Crowding isn’t your friend.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tomatoes-ripening-garden-outdoor-145055425">Slavica Stajic/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Space to spread out</h2>
<p>Tomatoes need plenty of room to grow. Commercially, most growers use a two-foot spacing within rows. If you want really large fruit, give them even more room. One of the most common errors by novice gardeners is planting tomato plants too close together. If you are just going for size, you need only a few good, healthy plants, with plenty of space around them.</p>
<p>Training plants to grow off the ground is a good idea to protect the quality of the fruit. Caging and staking are both fine. Just be sure to tie them frequently enough to support the plants. If you choose cages, you will need a mesh that is big enough to get your hand in, and to get that enormous tomato back out.</p>
<h2>Hydrated and well-fed</h2>
<p>Tomato plants need plenty of water, especially in hot weather, but will suffer if the ground stays saturated. As a rule of thumb, an inch and a half of water per week, from hose or from rain, is about right. The soil must be able to drain this water within a reasonably short time.</p>
<p>Be sure to water the plants thoroughly right after transplanting. After plants are established, always water deeply, once or twice per week, rather than giving them a light sprinkle every day; shallow watering leads to shallow roots. A good, thick mulch will help hold moisture in the soil around plants and also keeps the weeds down.</p>
<p>As for fertilizer, tomatoes need regular doses. Small, weekly amounts are better than large pre-plant amounts and one or two side-dressings. Liquid fertilizer is more quickly available to plants than granular forms. Some people like to use fish emulsion or “manure tea,” but any complete garden fertilizer will work.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/295320/original/file-20191002-49404-m5rbbu.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">Don’t let your plant squander its resources.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-green-shoots-ovary-tomato-flower-1431314588">Alexander Sobol/Shutterstock.com</a></span>
</figcaption>
</figure>
<h2>Focus on one flower</h2>
<p>One other tip, and this is important. Remove the first flower cluster or two so that the plant will produce more leaves before you allow it to set tomatoes.</p>
<p>Then, when the plant is big enough to set fruit, don’t let all of the fruit mature. Remove all but one fruit per cluster. Usually the first fruit to set on a cluster will be the largest, so snip off all of the other flowers or small fruit on that cluster. And don’t let too many clusters stay on the plant either.</p>
<h2>Prepare for prize-winning</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=866&fit=crop&dpr=1 600w, https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=866&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=866&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1089&fit=crop&dpr=1 754w, https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1089&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/295321/original/file-20191002-49356-pzux9o.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1089&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You don’t need to break a world record to win a local contest.</span>
<span class="attribution"><a class="source" href="http://www.apimages.com/metadata/Index/Associated-Press-Domestic-News-Massachusetts-Un-/bdf9e80d40e1da11af9f0014c2589dfb/1/0">AP Photo/Lisa Poole</a></span>
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<p>Once you’ve got your jumbo beauty, what about that big money? Start by looking for local, county or state contests. Ask your State Department of Agriculture or County Extension Agent.</p>
<p>Good luck and remember to think big. The record continues to be broken every so often, which tells you that the upper limit has still not been found. </p>
<p>And if you just don’t have much luck growing gargantuan tomatoes, console yourself with the knowledge that while these techniques maximize for size, they do not maximize flavor. When plants get too much water, for example, the fruit can be bland. Your more average-sized tomatoes may be more delicious at the table.</p>
<p>[ <em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://theconversation.com/us/newsletters?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=youresmart">You can read us daily by subscribing to our newsletter</a>. ]</p><img src="https://counter.theconversation.com/content/124374/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Richard G. Snyder has received funding from Mississippi Specialty Crops Block Grant, USDA Risk Management Agency, Mississippi Urban Forestry Council, Mississippi Department of Energy, and similar organizations to support his research and Extension program.</span></em></p>Have you recently harvested a big fruit from your garden? Here an expert’s tips on how to go from jumbo to gargantuan with your tomatoes.Richard G. Snyder, Professor of Horticulture & Extension Vegetable Specialist, Mississippi State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1151212019-05-03T03:24:26Z2019-05-03T03:24:26ZThe tasty, weed-like desert raisin plant is as big as a carpark<figure><img src="https://images.theconversation.com/files/272394/original/file-20190503-103053-1phtxae.png?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The desert raisin is a member of Australia’s native bush tomato family. </span> <span class="attribution"><span class="source"> Mark Marathon/Wikimedia, CC BY</span></span></figcaption></figure><p><em>Sign up to the Beating Around the Bush newsletter <a href="https://theconversation.com/au/newsletters">here</a>, and suggest a plant we should cover at batb@theconversation.edu.au.</em></p>
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<p>The species <em>Solanum centrale</em>, also known as kutjera in several Aboriginal languages, or the desert raisin in English, stands out in Australia’s wild bush tomato family in more ways than one.</p>
<p>A typical desert raisin plant in the wild looks fairly unimpressive from the surface, and certainly a lot less striking than the photos which pop up in an internet search. </p>
<p>In fact, if you don’t know what you are looking for, you may miss them. They are fairly scrawny with greeny-grey hairy leaves and grow no taller than to the bottom of your shin. </p>
<p>You might only spot a shoot every few metres between other shrubs. Each shoot only has a handful of leaves, and it typically carries three to 10 sultana-sized fruit. Like sultanas, they’re unappealingly brown and shrivelled. And you’ll only see them if they have escaped hungry desert fauna.</p>
<p>But its humble appearance belies its significance to both people and the environment. </p>
<p>The fruit from this plant has been a staple in desert communities for thousands of years. It resembles a raisin but tastes like a piquant or smoky sun-dried tomato, and because it dries on the plant it has a long storage life relative to other fruit. </p>
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<p>
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<strong>
Read more:
<a href="https://theconversation.com/can-we-be-australian-without-eating-indigenous-food-53742">Can we be Australian without eating indigenous food?</a>
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<p>Its cultural significance and ability to grow in sandy arid areas where almost no other domesticated plants survive makes this species a prime target for an enterprise based in remote Aboriginal communities, producing a unique fruit with <a href="https://books.google.com.au/books?id=vyduivlx4kwC&printsec=frontcover&source=gbs_ViewAPI&redir_esc=y#v=onepage&q&f=false">plenty of health benefits</a> to consumers.</p>
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<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=802&fit=crop&dpr=1 600w, https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=802&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=802&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1008&fit=crop&dpr=1 754w, https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1008&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/272421/original/file-20190503-103049-12n7261.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1008&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="attribution"><span class="source">The Conversation</span></span>
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<h2>What makes the desert raisin unique?</h2>
<h3>Iceberg-like growth</h3>
<p>Like an iceberg which is much bigger under the surface than appears from above, the desert raisin plant is much bigger under the surface of the ground than it appears. A single plant in the wild can span <a href="https://www.abc.net.au/news/rural/2011-07-06/the-biggest-bush-tomato-plant-in-the-world/6183662">dozens of metres</a> through hardy underground connections. The <a href="http://www.nintione.com.au/resource/Waycott_GeneticDiversity_DKCRC_CP2.1_FinalReport_04Oct2010.pdf">largest confirmed</a> single plant was about one quarter of a hectare – but who knows how big these plants can really grow?</p>
<p>It expands in multiple directions from the seed plant over successive rains via roots which grow roughly parallel to the surface, producing new shoots as it expands.</p>
<p>Root sprouting allows a plant to grow a new shoot many metres away from the previous shoot while avoiding a vulnerable seedling stage. This feature is common among many unrelated desert plant families. </p>
<p>For example, a single <em>Populus euphratica</em> tree in the hyper-arid Taklamakan Desert of China was found to <a href="https://www.ncbi.nlm.nih.gov/pubmed/21622383">produce clonal shoots</a> over an area of 121ha. </p>
<h3>Unabated resilience</h3>
<p>Desert raisins are known to grow vigorously following a disturbance, either natural or man-made. It is quite common, for instance, when driving through Australia’s arid interior to find piles of sand beside freshly graded roads covered in bush tomato shoots after rain. </p>
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<strong>
Read more:
<a href="https://theconversation.com/the-black-wattle-is-a-boon-for-australians-and-a-pest-everywhere-else-100529">The black wattle is a boon for Australians (and a pest everywhere else)</a>
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<p>This is because a grader, a tool that smooths the surface of a road, cuts dormant roots and throws them, mixed with sand, onto the side of the road. The roots are ready to re-sprout as soon as they get wet. </p>
<p>And its not only chopping roots that appears to stimulate growth – <a href="https://www.jstor.org/stable/3566388?seq=1#metadata_info_tab_contents">targeted fires</a>, fruit collection <a href="https://www.agrifutures.com.au/wp-content/uploads/publications/07-030.pdf">by Indigenous groups</a> and grazing by <a href="https://www.jstor.org/stable/2399203?seq=1#metadata_info_tab_contents">desert marsupials</a> have all been known to increase the vigour of patches of wild bush tomatoes over the long term. </p>
<p>The traditional custodians of this country knew how to manage this species for sustainable production, and people from Aboriginal nations which span the large range of edible bush tomato species have passed this knowledge down for centuries.</p>
<h2>Cultivation</h2>
<p>Do the unique root properties of the desert raisin remind you of a weed? </p>
<p>Well, yes. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/268904/original/file-20190412-44805-lusm7f.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">When cultivated, desert raisin plants are large and thick, sometimes as high as the knee, with dozens of flowers per plant.</span>
<span class="attribution"><span class="source">Wikimedia</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Other root sprouters in the <em>Solanum</em> family from temperate areas are vigourous weeds in cropping regions <a href="http://clopla.butbn.cas.cz/public/05Evol&Ecol04-4B.pdf">around the world</a>. </p>
<p>Colonies are very difficult to eradicate as the viability of roots is not affected by cultivation and most herbicides. In fact, <a href="http://agris.fao.org/agris-search/search.do?recordID=JP2005002075">cultivation stimulates</a> sprouting from root fragments.</p>
<p>So how does this influence the way this species can be used as a food crop? </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/warrigal-greens-are-tasty-salty-and-covered-in-tiny-balloon-like-hairs-112307">Warrigal greens are tasty, salty, and covered in tiny balloon-like hairs</a>
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<p>There are currently several cultivated stands in regional and remote Australia, and the <a href="https://www.abc.net.au/news/2018-06-15/native-bush-food-helping-remote-nsw-community-thrive/9870698">benefits</a> of growing the species are becoming clearer, particularly for Aboriginal communities. </p>
<p>With water and nutrition in their natural habitats, bush tomatoes can become incredibly productive. When cultivated, the plants are large and thick, sometimes as high as the knee, with dozens of flowers per plant. But over the seasons they respond less to water and fertiliser. </p>
<p>It is at this point that perhaps a disturbance can be used to stimulate production from underground lateral roots – although if they pop up in the space between beds, it can create havoc for other operations!</p>
<p>It is no wonder that a plant, which normally hides its massive size so it can persist in harsh conditions, becomes a showy, vigorous plant when given the same kind of treatment as horticultural plants. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-aboriginal-people-need-autonomy-over-their-food-supply-41812">Why Aboriginal people need autonomy over their food supply</a>
</strong>
</em>
</p>
<hr>
<p>One final note. Much of the knowledge on how bush tomato and other food plants native to this country work is held by the traditional custodians of the species, the Aboriginal people. </p>
<p>We must all learn from Aboriginal and Torres Strait Islander people, listen, and work together so the amazing fruits of this land return to their place in human diets and landscapes, including the mighty desert raisin.</p>
<p><br></p>
<hr>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=199&fit=crop&dpr=1 600w, https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=199&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=199&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=251&fit=crop&dpr=1 754w, https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=251&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/238283/original/file-20180927-48650-1veiqyi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=251&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<p><em><a href="https://www.facebook.com/groups/BeatingAroundTheBush">Sign up to Beating Around the Bush, a series that profiles native plants: part gardening column, part dispatches from country, entirely Australian.</a></em></p><img src="https://counter.theconversation.com/content/115121/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dr Angela Pattison received funding from the Desert Knowledge CRC and CSIRO to complete her research on the root systems of bush tomatoes. </span></em></p>Tasting like a smoky sundried tomato, the desert raisin has been a staple for Australian desert communities for thousands of years.Angela Pattison, Research scientist at Plant Breeding Institute, University of Sydney, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/998122018-07-23T10:22:57Z2018-07-23T10:22:57ZA brief history of ketchup<figure><img src="https://images.theconversation.com/files/228700/original/file-20180722-142438-k7576v.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Heinz is why ketchup seemed to become distinctly American.</span> <span class="attribution"><span class="source">Reuters/Mike Blake</span></span></figcaption></figure><p>Trade wars have an interesting way of revealing cultural stereotypes. </p>
<p>Countries often propose tariffs not on the most valuable items in their trading relationships – since that would be painful to them as well – but rather products iconic of national character. A good example of this came in the European Union’s retaliation against U.S. steel tariffs. Among the US$3.3 billion in goods it <a href="http://trade.ec.europa.eu/doclib/docs/2018/march/tradoc_156648.pdf">slapped a tariff</a> on in May were Harley-Davidson motorcycles, Kentucky bourbon and Levi’s jeans. </p>
<p>Now, American ketchup is being targeted, both by the EU and Canada. The United States’ northern neighbor <a href="https://qz.com/1318475/the-full-list-of-229-us-products-targeted-by-canadas-retaliatory-tariffs/">imposed</a> a 10 percent tariff on the product in July, while the <a href="https://www.ft.com/content/e3f9b700-809b-11e8-bc55-50daf11b720d">EU has suggested</a> it would be a part of the next round of retaliatory tariffs, which could go into effect <a href="https://www.bloomberg.com/news/articles/2018-07-19/eu-is-said-to-prepare-car-tariff-retaliation-before-trump-talks">within weeks</a>. </p>
<p>The EU’s threat is mostly symbolic because it is already a significant producer of ketchup – including by American brands like H.J. Heinz – and imports very little of the tomato condiment from the U.S. Canada, however, as recently as 2016 <a href="https://atlas.media.mit.edu/en/visualize/tree_map/hs92/export/usa/show/210320/2016/">imported</a> more than half of all the ketchup American companies send abroad. </p>
<p>In either case, at least part of the reasoning behind using it as a weapon in the growing trade war seems to be that ketchup, also spelled catsup, is one of those products that sounds distinctly American, poured generously on burgers and fries at baseball parks and Fourth of July barbecues across the U.S. </p>
<p>But in fact, the irony is that this ubiquitous condiment is anything but American in its origins or in those nationalities that love it the most. As a <a href="https://theconversation.com/profiles/ken-albala-204565">historian of food</a>, I see it as a truly a global product, its origins shaped by centuries of trade. And different cultures have adopted a wide variety of surprising uses for the condiment we know as ketchup today.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/228666/original/file-20180720-142432-8diifi.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">Some people even put ketchup on their pizza.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Pizza_s_ke%C4%8Dupem.jpg">Wikimedia Commons/Dezidor</a></span>
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<h2>The origins of ‘ke-chiap’</h2>
<p>Although ketchup is <a href="https://www.merriam-webster.com/dictionary/ketchup">defined</a> by Merriam-Webster as a “seasoned pureed condiment usually made from tomatoes,” in the past it has been concocted from a wide variety of ingredients. </p>
<p>China – another country with which the U.S. is in the middle of a serious trade spat – <a href="http://andrewfsmith.com/books/pure-ketchup">was likely the original source</a> of the condiment with something that sounded like “ke-chiap.” It likely originated as a fish-based sauce <a href="https://www.history.com/news/ketchup-a-saucy-history">many centuries ago</a>, a condiment akin to the many fermented sauces one finds throughout southeast Asia. It was primarily used as a seasoning for cooking. </p>
<p>From there it made its way to the Malay Peninsula and to Singapore, where British colonists first encountered what locals called “kecap” in the 18th century. Like soy sauce, it was deemed exotic and perked up what was a comparatively bland British cuisine, such as roasts and fried foods.</p>
<p>English cookbooks of the era reveal how it was soon transformed into a condiment made with other bases such as mushrooms or pickled walnuts, rather than only fish. <a href="https://books.google.com/books/about/The_compleat_housewife_or_Accomplished_g.html?id=XvMHAAAAQAAJ">E. Smith’s “Compleat Housewife”</a> includes an anchovy-based “katchup” with wine and spices, more akin to Worcestershire sauce than what we think of as ketchup. </p>
<p>A more significant transformation took place in the early 19th century in the U.S. when it was made with tomatoes, sweetened, soured with vinegar and spiced with cloves, allspice, nutmeg and ginger – pretty much the modern-day recipe. </p>
<p>The first published recipe for tomato ketchup was written in 1812 by Philadelphia scientist and horticulturalist James Mease in his “Archives of Useful Knowledge, vol. 2.”</p>
<h2>Heinz makes it ‘American’</h2>
<p>Heinz, the American company perhaps most associated with ketchup, <a href="https://blogs.scientificamerican.com/anthropology-in-practice/seeing-is-believing-the-story-behind-henry-heinzs-condiment-empire/">didn’t get into the game</a> until 1876, seven years after Henry John Heinz set up the company to sell horseradish using his mother’s recipe. After his initial company went bankrupt, he launched a new one and began bottling tomato “ketchup,” spelled that way to distinguish it from other catsup brands.</p>
<p>From here, ketchup took on a uniquely American character and began its career as not only a universal condiment but a mass-produced brand-name article of trade that could last indefinitely on the shelf, be shipped around the world and used in ways never imagined by its creators. </p>
<p>Like so many other products, it became emblematic of American culture: quick, easy, convenient and too sweet but also adaptable to any gastronomic context – and a bit addictive. Ketchup became the quick fix that seemed to make any dish perk up instantly, from meatballs to scrambled eggs.</p>
<p>In a sense, it also became a “mother sauce,” meaning that one can concoct other sauces with ketchup as the base. Barbecue sauce usually uses ketchup, as does cocktail sauce for shrimp, with the addition of horseradish. Think also of <a href="https://www.epicurious.com/recipes/food/views/russian-dressing-51182860">Russian dressing</a> or <a href="https://www.allrecipes.com/recipe/18542/thousand-island-dressing-ii/">Thousand Island</a>. Or consider various recipes that are often ketchup laden, like <a href="https://www.thewholesomedish.com/the-best-classic-meatloaf/">meatloaf</a> and <a href="https://www.seriouseats.com/recipes/2014/03/thai-sweet-chili-ketchup.html">chili</a>.</p>
<h2>How the world consumes ketchup</h2>
<p>While ketchup is indeed an American staple – <a href="https://www.npr.org/sections/codeswitch/2013/12/02/248195661/ketchup-the-all-american-condiment-that-comes-from-asia">97 percent of households</a> have a bottle on hand – it’s very popular around the world, where the condiment is used in a lot of surprising ways. </p>
<p>Although practically sacrilegious in Italy, ketchup <a href="https://www.foodbeast.com/news/think-about-ketchup-on-a-pizza/">is often squirted on pizza</a> in places as far flung as Trinidad, Lebanon and <a href="http://articles.chicagotribune.com/1991-07-02/news/9103160121_1_pan-pizza-poland-limited-menu">Poland</a>. Similarly, ketchup is even used as a substitute for tomato sauce in pasta dishes in countries such as in Japan, which created a catsup-based dish called <a href="https://www.thespruceeats.com/spaghetti-napolitan-japanese-ketchup-pasta-2031629">spaghetti Napolitan</a>.</p>
<p>In the Philippines there’s a <a href="http://www.foodrepublic.com/2015/09/02/banana-ketchup-the-philippines-answer-to-a-lack-of-tomatoes/">popular banana ketchup</a> that was invented when tomatoes ran short during World War II but otherwise looks and tastes like tomato ketchup. In Germany the local favorite is a <a href="http://currywurstmuseum.com/en">curry powder-spiked ketchup</a> that goes on sausages sold by street vendors everywhere. </p>
<p>Without doubt the most intriguing recipe comes from Canada, where people enjoy <a href="http://www.kraftcanada.com/recipes/great-canadian-heinz-ketchup-cake-193998">ketchup cake</a>, a sweet red frosted layer cake that is much better than it sounds. </p>
<p>The modern variety of ketchup even returned home to China to become the base of many Chinese or perhaps more properly Chinese-American dishes like <a href="https://www.seriouseats.com/recipes/2012/01/sweet-and-sour-sauce.html">sweet and sour chicken</a>. Ketchup is sometimes a stand in for tamarind in <a href="https://www.bbc.com/food/recipes/padthai_67953">pad thai</a>. </p>
<p>But the best recipe comes from my father who once told me that during the Great Depression people without money would ask for a cup of hot water to which they would add some free ketchup and have a meal of tomato soup.</p>
<h2>Ketchup lovers today</h2>
<p>Today, the U.S. is the biggest exporter of ketchup and other tomato sauces by country. In 2016, it exported $379 million worth, or 21 percent of all trade in the product category. While only 1.9 percent of that – $7.3 million – <a href="https://atlas.media.mit.edu/en/visualize/tree_map/hs92/export/usa/show/210320/2016/">went to Europe</a>, a whopping 60 percent – $228 million – was exported to Canada.</p>
<p>Heinz is among the <a href="https://www.mordorintelligence.com/industry-reports/ketchup-market">biggest producers</a>, with a market share of 80 percent in Europe – via <a href="https://www.kraftheinzcompany.eu/news/the-largest-ketchup-factory-in-europe/">factories</a> in the U.K., Netherlands and elsewhere – and 60 percent in the U.S.</p>
<p>Put together, however, Europe actually <a href="https://atlas.media.mit.edu/en/visualize/tree_map/hs92/import/all/show/210320/2016/">exports</a> the most ketchup, with 60 percent of the global trade – including countries not in the EU. </p>
<p>What does all this mean for the tariffs? Since the EU produces plenty of ketchup within the bloc, its proposed tariff will probably have very little impact. For Canada, however, the effects could be more complicated since it’s unclear whether it can supply enough ketchup domestically or from other countries to meet high demand.</p>
<p>Whether Canadians will find an alternative for Heinz remains to be seen. But what is clear is that while the signature bottle proudly bearing the number 57 may be quintessentially American, its roots are global and its progeny likewise.</p><img src="https://counter.theconversation.com/content/99812/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ken Albala 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>Canada recently slapped a tariff on US exports of the tomato-based condiment, and the EU plans to do the same, perhaps on the notion that it’s distinctly American. In fact, ketchup’s origins are global, as are its fans.Ken Albala, Professor of History, University of the PacificLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/719162017-01-26T18:25:34Z2017-01-26T18:25:34ZScientists have unlocked the secret of making tomatoes taste of something again<figure><img src="https://images.theconversation.com/files/154388/original/image-20170126-30424-1annqdy.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">Shutterstock</span></span></figcaption></figure><p>If you shop in a supermarket you may well have asked why the fruit and veg you buy there is so tasteless, especially if you’ve also tried homegrown alternatives. Traditional breeds of tomatoes usually grown in gardens, known as heirloom tomatoes, for example, are often small and strangely shaped and coloured but renowned for their delicious taste. Those in the supermarkets, meanwhile, are often pumped up in size but somewhat insipid to eat.</p>
<p>This is because plants used by most tomato farms have gone through an intensive artificial selection process to breed fruit that are big, red and round – but at the expense of taste. Now a 20-strong international research team <a href="http://science.sciencemag.org/cgi/doi/10.1126/science.aal1556">have identified</a> the chemical compounds responsible for the rich flavour of heirloom tomatoes and the genes that produce them. This information could provide a way for farmers to grow tomatoes that taste of something again.</p>
<p>The unique flavour of a tomato is determined by specific airborne molecules called volatiles, which emanate from flavour chemicals in the fruit. By asking a panel of consumers to rate over a hundred varieties of tomato, the researchers identified 13 volatiles that play an important role in producing the most appealing flavours. They also found that these molecules were significantly reduced in modern tomato varieties compared to the heirloom ones. And they found that bigger tomatoes tended to have less sugar, another reason why large supermarket fruits often fail to inspire.</p>
<p>Tomatoes <a href="https://academic.oup.com/aob/article/100/5/1085/136832/Domestication-and-Breeding-of-Tomatoes-What-have">originally hail</a> from the Andean region of South America and belong to the Solanaceae family, making them relatively close relations of potatoes and peppers. The original, ancestral tomato was very small, more like a pea, showing just how much human intervention has swollen the fruit. We don’t know how long they have been grown for human consumption but they had reached an advanced stage of domestication by the 15th century when they were taken to Europe.</p>
<p>Before the 20th century, tomato varieties were commonly developed in families and small communities (which <a href="http://www.salon.com/2015/06/14/heirloom_tomatoes_bizarre_evolution_the_secret_history_of_the_tastiest_summer_treat/">explains the name “heirloom</a>”). With the industrialisation of farming, the <a href="http://www.actahort.org/members/showpdf?booknrarnr=100_1">serious business of tomato breeding</a> began with intensive selection for fruit size and shelf life. </p>
<p>Some <a href="https://academic.oup.com/aob/article/100/5/1085/136832/Domestication-and-Breeding-of-Tomatoes-What-have">more recent effort</a> has been put into improving the flavour of tomatoes through breeding. But the new research appears to indicate that this has ultimately been unsuccessful and that earlier breeding efforts have doomed modern commercial varieties to mediocrity. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/154391/original/image-20170126-30413-1r3vpik.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">Family heirlooms.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>The new paper, <a href="http://science.sciencemag.org/cgi/doi/10.1126/science.aal1556">published in Science</a>, emphasises what seems to be a constant conflict between the food industry’s desire for profit and what the public actually want. The researchers tactfully excuse the way tomatoes have been bred for size and shelf-life at the expense of taste as being down to breeders’ inability to analyse the fruit’s chemical composition and find the right volatiles.</p>
<p>But many people will find this hard to swallow. After all, the new research itself used the most ancient volatile analysis system there is: the human taster. It wouldn’t have taken much for farmers to incorporate taste trials into their breeding programmes.</p>
<p>Because modern farmed tomatoes have only lost their flavour in the last hundred years or so and varieties are still available that produce the tasty volatiles, it should be possible to reinsert the crucial taste genes back into commercial varieties. This could be done by genetic modification or conventional breeding. Just as we are seeing a resurgence in <a href="https://www.ft.com/content/ed0edb8e-d9ab-11e5-a72f-1e7744c66818">organic and artisan growing</a>, it would be great to see a new generation of tomato breeders interested in returning flavour to the fruit using wild and heirloom varieties, while maintaining other commercially desirable traits. </p>
<p>There is significant <a href="https://theconversation.com/why-scientists-failure-to-understand-gm-opposition-is-stifling-debate-and-halting-progress-62142">public opposition</a> to the idea of genetically modifying foods by inserting genes into a plant’s DNA in the lab. But the idea of reinserting lost genes <a href="https://theconversation.com/all-our-food-is-genetically-modified-in-some-way-where-do-you-draw-the-line-56256">may be more palatable</a> to the public than introducing completely new ones. Either way, it shows how perverse the food industry’s methods are that we may need to use one of the world’s most advanced technologies to give an inherently delicious food some flavour.</p><img src="https://counter.theconversation.com/content/71916/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Colin Tosh receives funding from the UK Biotechnology and Biological Sciences Research Council (BBSRC) and previously has recived grants from the UK Natural Environment Research Council (NERC). He is active at a local level with the Green Party, England and Wales. </span></em></p><p class="fine-print"><em><span>Niall Conboy receives funding from BBSRC</span></em></p><p class="fine-print"><em><span>Thomas McDaniel receives funding from BBSRC. </span></em></p>New research pinpoints the genes that could counteract decades of bland breeding.Colin Tosh, Lecturer in Ecology, Evolution and Computational Biology, Newcastle UniversityNiall Conboy, PhD candidate, Newcastle UniversityThomas McDaniel, PhD candidate, Newcastle UniversityLicensed as Creative Commons – attribution, no derivatives.