basically, we are in the process of killing our soil. that is not a renewable resource dead soils - how can we revive our exhausted cropland? traditional seeds - could these boost harvests in tunisia? and could gene editing help us feed the world?

these are living on your body. but don't worry! they're supposed to be there. they're microbes, and the planet is covered in them. and there are tons of them in the soil because they literally make fertilizer for plants. these are some of the only things on earth that can do this. ” we depend on soil for almost all of the food that we eat, and because 90 % of the planet's soil could be degraded by 2050, scientists and even agribusiness think microbes could be key to averting a food crisis. so, let's take a journey to the invisible world right under our noses and our feet. to see what happens to soils when microbes get out of whack we can look back to the 1930 s in the united states settlers replaced native grasses with farmland and then intensively tilled, which killed microbes and degraded the soil. after a series of droughts, the damaged soil was easily

picked up by the wind and turned into so-called 'black blizzards'. millions of tons of topsoil just blew away in what came to be known as the dust bowl. although farming methods have changed somewhat, soil degradation is still a global problem. “what we are doing basically is destroying the soil, that is a non-renewable resource. what we have been doing so far, during the last 200 years maybe, is to use soils as a substrate to grow plants. ” we've been undervaluing them and expecting them to stay healthy. but tilling, overusing chemicals, and climate change are harming our soils. this is a problem for growing food, as well as resources for clothing and construction. soil is also key to storing carbon and filtering water. to make soils healthy again we need to start seeing them as what they are: entire ecosystems teeming with hidden life, all

run by microbes. all this under our feet is topsoil, where most of the insects and microbes live, along with plant roots and small animals. ” one gram of this can contain millions of microbes and a few worms. ” a healthy soil will have a diversity of microbes. the most common ones are bacteria, and fungi. one of their most important jobs is transforming nutrients. every single nutrient cycle on the planet is mostly driven by microbes. none of these cycles really exist in a vacuum. they're all interlinked. ” one of those nutrient cycles is with carbon. plants and animals are made mostly of carbon, and when they die, they are broken down by microbes. no microbes, no decomposition. the microbes use some of the carbon to reproduce, storing it in the soil, and breathe the rest of it out, sending it back to the atmosphere. another nutrient cycle happens with nitrogen, which makes up

most of the air around us, and is one of the main nutrients plants use to grow. plants can't get it from the air by themselves, so they partner up with microbes. and we can find evidence of the nutrient cycle by looking at certain plants, like these beans, which are considered 'nitrogen-fixing'. the beans create these little root nodules, that become home to a type of bacteria. in return, they change nitrogen into a form that the plants can access. microbes, specifically fungi, also exchange other nutrients with plants. they have very fine roots called hyphae that intertwine themselves with the roots of the plant “the fungus is really good at releasing things, like phosphorous, from soils, which is hard for plants to get at. so, it does that and exchanges that with the plant in return for things like sugars, which the plant can make through photosynthesis. ” there's also some evidence this relationship makes the plant more able to withstand drought and disease, in a degraded soil, these nutrient cycles aren't working as well as

they could be. climate change is one cause of degrading soils with drought and extreme weather causing them to dry out and erode. intensive agriculture can be another cause as pesticides and herbicides kill off beneficial microbes and reduce their activity. the more degraded soil is, the more chemicals are needed to grow stuff, degrading the soil even further. this whole plot of land was intensively farmed for 30 years and you can really see it in the soil. it's super sandy, dry, and degraded. degraded soils also lose their ability to hold and filter water, are more susceptible to erosion and have less of those beneficial microbes, meaning plants don't grow as well. but soil health is about more than just our food security. soil communities and soil health is actually the foundation of all ecosystems, both natural and manmade. if the foundation of something crumbles, everything else

comes tumbling down. ” and agriculture might actually hold the key to making our soils healthy again on this same plot of land, not so far away from the degraded bit, years of regenerative agriculture have brought back a lot of microbial activity. the soil looks completely different. this farm is a best-practice example: no chemicals are used, and the soil microbes are flourishing. just look at how beautiful these tomatoes are. no till agriculture leaves soil undisturbed, which allows the microbes living inside the clumps to thrive. specifically, those fungi hyphae, which are important for soil structure. there can be a kilometer of them in a gram of soil. and cover crops, planted to leave in the ground, provide microbes with carbon to chow down on as well as reduce erosion and nutrient loss. unfortunately, this kind of farming just isn't possible everywhere. “if you can do it, that's fantastic.

it's what we want in terms of soil health. but the problem is the vast amount of areas where the soil is so degraded that these techniques are not strong enough to recover the soil in due time. ” here's where microbes come in on a larger scale. the most common use is as biofertilizers. they're used like chemical-based fertilizer except they contain fungi or bacteria. soil degradation is a big enough threat that bayer, a company known for selling agricultural chemicals is also interested “they are currently already used in a number of countries. biological alternatives will certainly be an alternative and will certainly help to reduce chemical fertilizers. ” the company is also investing in seeds that have been infused with microbes, because delivering microbes along with

seeds is the most targeted way to apply them. seeds can also be planted with a coating of microbes. conservation organizations are using this approach to restore ecosystems. a problem with commercial microbial products is that the microbes are not specifically adapted to the environment. non-native microbes could find it hard to survive rendering the process useless. and because these are living organisms, they could cause an imbalance in the microbiome. “this is something we really have to take into consideration, especially with fungi, because they spread faster and they are more efficient in design. ” even bayer agrees “just because they are natural, it doesn't necessarily mean that they automatically are not harmful. ” since soils are different around the world, we would ideally develop microbial products for specific regions. but that will take time and more research.

unfortunately, our soil health is an emergency. “we are going to need it because we have to recover soils. and this is the cheapest way to recover it because we are recovering them while we are maintaining productivity. so, for large farms, biofertilizers are a step above chemicals and where possible, agriculture that relies on helping native microbes - like on this farm - is the way to go an eggplant harvest not far from the tunisian capital. here on his one-and-a-half hectares of land, salim marzougui farms fruit and vegetables. his yields are smaller than they are when he uses imported or genetically modified seeds.

but he still prefers local seeds. they don't look particularly good, sometimes they're small and crooked. but they produce better quality fruit, more nutritious and tastier - and better adapted to our climate. he avoids artificial fertilizers as well. he prefers to make his own compost. we're trying to produce our own organic fertilizer. first i use chicken excrement, because it has a lot of nitrogen. then we add remnants of fruit and vegetables that are thrown out at markets. finally, we add a bit of hay, which has a lot of carbon. for decades, tunisia's government bought both hybrid and genetically engineered seeds.

they were meant to produce greater yields. the country still imports around 85 % of its seeds today. but increasing numbers of farmers want to return to using local seeds and tunisia's seed bank has been able to help them. they found ancient seeds from tunisia in other countries, which they brought back. since 2008, they've collected more than 7,700 different seed types. the work we're doing today focuses on genes, as well as which genotypes impact crop quality -- and whether or not these traits fit a particular criteria. we might be able to use them for cross-pollination, which would, in turn, lead to improved yields. to help better market his products, salim marzougui goes to fairs on a regular basis. they focus on investments and technological developments in farming.

this year's slogan is sustainable agriculture, which is a growing trend in tunisia as well. the farmers' local seeds are known for their unique taste and health benefits. these are the seeds our grandparents were familiar with. they always found the best ones and passed them on. it's an inheritance they've passed on to us young farmers. every year they gather the best seeds. salim marzougui is fortunate to live so close to the capital. he can market his products at lots of different places, including at sustainable farming events in tunis. organic farmers can sell their goods here once a week. we're fighting for independent food production on multiple fronts. we're trying to get farmers to gather seeds.

at the same time, we're trying to produce more seeds together with our partners. we're also doing our best to educate farmers and show them how they can contact clients directly or via social media. the organization hopes that more people will use traditional, local seeds as alternatives to imported ones. salim marzougui has started collecting his own, like these eggplant seeds. i've grown aware of the important role that local seeds play, and i'm using that knowledge. the demand for the orginal seeds has risen and the prices have gone up along with it -- which seed sellers are taking advantage of. these seeds should really be available to all farmers. the best case scenario would be farmers obtaining and reproducing them themselves.

the strategy has worked well with the eggplants, and now the farmer hopes it will be just as fruitful with his other crops. and also with an eye on the worsening drought in the country, he says, traditional seeds fare better than imported varieties. we started improving plants by cross-breeding the best varieties. the first records of humans selecting ancient grass and wheat date back 10,000 years. since then we've multiplied corn, wheat, rice and soy yields by several times and bred them to something which would probably be hard to identify for one of the early settlers back then. for example, do you know what this is? today it looks like this. doesn't seem like a close relative, does it? in the past decades, yields have skyrocketed.

to feed an ever increasing population, we did not stop at just multiplying yields. our excessive use of fertilizers, pesticides and the ongoing conversion of sensitive ecosystems to cropland have degraded 40 % of fertile soils globally. what's more, the climate crisis is forecast to reduce harvests. the problem is: we actually need to produce more, but without using more land and more resources. there's a 50 % gap between the food produced today and what we're need in 2050, just to feed people adequately. if everyone became a vegetarian, we could produce enough - sustainably. but that doesn't look like it'll happen any time soon. so if we just stick at the current yield rate and say, oh, it's great, we can pat ourselves on the back and move on, then the only way that we would meet those needs is to expand the agricultural frontier even further, which means sort

of goodbye to the remaining natural ecosystems. scientists are designing climate resilient super crops that might produce higher yields and need fewer resources to grow. they want to speed up the process by changing the plants' genetic code with genome editing -- such as with rice. drought is a big issue: “it is brutal down there” drought emergency! ” unprecedented droughts and heatwaves have put water scarcity into sharp focus. that's a problem for rice, a thirsty crop used to being soaked. a new breed might help in the future. this variety, ir 64, is mostly grown in the global south -- but is eaten worldwide. scientists tweaked its genes to make it more drought resistant. the new rice uses up to 40 percent less water in some weeks. while the conventional varieties did not survive a week without water in 40 -degree heat, half of the gene edited plants did. scientists did this by instructing a

naturally-occurring gene in the plant to be more powerful. this gene helps reduce the number and size of the plant's pores, which are responsible for gas and water exchange. fewer and smaller pores meant the plant saved water. yields increased or remained the same. the method they used here is called crispr-cas 9, also known as genetic-scissors, or genome editing. it is fundamentally different to traditional genetic modification or gm technologies. it relies actually on natural processes. but it makes the mutation process much less random. most gm products contain a synthetic gene, or a gene from another organism inserted into the plant or animal of interest. insect-resistant cotton and maize for example, grown widely around the world, contain a gene originally found in bacteria. instead of using foreign dna, gene editing makes changes in the characteristics of any organism using the information

present in its own genetic code. using special enzymes working like scissors, we can delete, swap or repeat genes present in the plant's dna. “it will take many dozens of generations until you have only this one gene transferred by crossing and then often will not be very viable because it would just take too long. so there genome editing is really super powerful because you can go in the single gene, change it. and voila! it takes seven to 15 years to get a cross-bred plant with the desired trait. with gene editing, just a couple of months plus a few years of testing. globally, gene editing research is speeding up: from only a couple of patents filed in 2011 to about 2,000 patents in 2019 by private companies and public researchers. the u.s., china, and multinationals are investing heavily in the technology, which is expected to develop into a

multi-billion dollar market by the end of the decade. it's risky. especially as many new crop varieties are still in the research phase and little data and few risk assessments exist. we're then going to see what happens in nature. it's all uncertain and it will be really experimentation that will be far ahead of the science. the science will have to catch up. some experts point to cases of off-target genetic changes, or cases of deleting much more genetic information then intended. additionally, genes involved in increasing yields in some type of drought could decrease yields in wet years and as there is large number of genes involved, turning one or two genes on or off is mostly not enough here. the less optimized a crop, the easier it is to improve. that's why experts see most potential in quickly developing old varieties that haven't been part of industrial production so

far such as millet, einkorn wheat or manioc, which already have stronger defences against climate-related challenges, but where breeding is still in its infancy. so i don't want to take anything off the table. the challenge is so significant. i don't want to take crispr technology, i don't want to take shifting diets, i don't want to take restoration. it's all of these things. in the eu genetically edited crops are labelled gm and therefore heavily regulated. but there's increasing discussion about whether the gm label is still appropriate. or if genome editing should be considered a new breeding method instead of classic genetic manipulation. in the u.s., china and many latin american countries, genome edited crops don't need to be labelled or controlled as gm and the sector plans to bring several crops to the fields in the coming years. as highly advanced as genome editing methods may be, conventional breeding will remain as important.

neither will be able to make up for the huge burden we currently put on our ecosystems, but they'll probably fill the food gap in the future. that ancient khasis folk song describes the close bond between humanity and nature. richard ranee rani belongs to the 50 or so families who live here in the mountains of cherapunji, in northeast india's meghalaya state. the song asks nature for her gifts, like the wild plants growing among the flower beds.

these are garlic chives, which we eat. this is a wild edible. and then we have pineapples which we cultivate. during the months of september and october they're ready to harvest. and we cultivate pineapples on the edge of our plot. ranee's home village of nongtraw is remote, and anyone who wants to visit has to scale two and a half thousand steps. the inhabitants here are an indigenous people. through their traditional way of life, they make an important contribution to biodiversity. three quarters of meghalaya is forested, so people here grow their crops among the wild trees and shrubs.

agro-ecologist gratia dhkar works for the north east slow food and agrobiodiversity society - or nesfas for short. the ngo wants to preserve the region's traditional cultivation and nutritional practices. so if we look at the way the indigenous communities have managed the food system, you will see a component of diversity where you will see there is in a system, in any of this system there is multi cropping. through a mapping exercise, we have found that a community have about more than 202 food plants. just a few years ago, there was more diversity, according to surveys by nesfas. but slash-and-burn forest clearance and increasingly heavy rainfall have both taken their toll on the soil.

in the 1990 s, the local farmers of nongtraw started cultivating broom grass to earn a living. it's used for livestock feed, to make brooms and fuel. but this monoculture has severely degraded the soil. it's a highly competitive plant and we can't plant this with the other crops because it damages the crop. but we plant it because of the high demand. as market prices for broom grass rose, farmers cultivated more and more of it - to the detriment of biodiversity in the region. nesfas has launched programs to revive what's been lost. like at the mawmithied lower primary school, where regional dishes are now back on the menu. almonds have been replaced by the traditional chinkapins,

peanuts by perilla seeds and lettuce by the chameleon plant. today i am eating nutrella with pumpkin, cabbage with perella seeds, rice and wild edibles. i find the food really tasty. my absolute favorite is the pumpkin. the ingredients are supplied by local farmers. nesfas has also helped to build a garden at the school. we do a comparative study of the local food with the government, commonly available food. and oftentimes we try to promote that the nutritional content of our traditional food is really much higher than the food that we buy from the market. nesfas now supports more than 130 villages in northeastern india. with the help of the ancient knowledge from the region, agriculture in the mountain forests is becoming more sustainable for future generations.

>> this is dw news from berlin the vaccine slamming hong kong, china issued the highest weather alert as saola comes ashore. businesses are closed. a rare show of dissent against the assad regime.