Cheaper food from fewer fertilisers

Cutting back on environmental damage is key to farming of the future...
07 February 2023
Presented by Chris Smith, James Tytko
Production by James Tytko.


Farmer fertilising wheat


Scientists and governments are working together to turn farming, one of the foremost causes of global emissions, into a future-proof industry. We'll hear about the UK governments new sustainable farming scheme which rewards farmers for eco-friendly practices, scientists working on reducing reliance on harmful and costly fertilisers for grain crops, and the food formed of microbes which might soon feature on supermarket shelves...

In this episode

Nature Friendly Farming

01:02 - Paying farmers to protect their land

Financial incentives from the UK government to be awarded to farmers for taking a sustainable approach...

Paying farmers to protect their land
Martin Lines, Nature Friendly Farming Network

Farmers: they’re the original friends of the earth who understand and appreciate environmental issues better than anybody. Rather, they’re often the motivated ones who want to make a difference to preserve their livelihoods. The government recognise this and are now introducing measures to reward good land stewardship practices. The Environmental Land Management Scheme (ELMS) recognises 280 different actions that can help to safeguard the environment. They are a post-Brexit replacement for the European Union’s Common Agricultural Policy (CAP) which mainly reimbursed farmers for the amount of land they farmed rather than how sustainable their farming practices were. These actions vary from conserving hedgerows to assessing the quality of soil. Martin Lines is the UK chair of the Nature Friendly Farming Network and James Tytko paid his Cambridgeshire farm a visit…

Martin - We're standing in quite a large arable field, but in the middle of the field we've put in some habitat strips to bring nature back into the centre of the field. So that means I no longer need to use insecticides and we have more pollinators and predatory insects in our farm landscape, which I can rely on to bolster my food production in a joined up fashion. Within this field, there was a cover crop, so that was capturing nutrients and stopping nutrient loss. That's a new reward. We've got better management of hedgerows... so much of the natural capital, the nature items in my landscape, are now going to get better reward. We weren't getting rewards for that in the past and we're moving away from that area based payment: just because I have a number of hectares I farm. So it'll underpin my farming business in a more sustainable way.

James - I've heard the criticism before that this new initiative is paying farmers for doing things that they're already doing?

Martin - Some things we were already doing because we've already recognised having nature in the landscape is a benefit. But for the majority farmers, they haven't been doing that. And government wants all farmers to go on this nature friendly farming journey of working with nature and halting the decline in nature and putting more nature back into the landscape. And we're going to get rewarded for doing that, which will also help our businesses.

James - I'm getting the impression then, not only as chair of the Nature Friendly Farming Network here in the UK, that you welcome these changes. This is something you're very behind.

Martin - Very much so. We've been working closely with government and with DEFRA about how do we design these so it actually works for farmers and all farmers can get involved. So we welcome the direction, which rewards active farmers doing the actions that society wants, which is real positive.

James - We've only spoken about two or three examples of things that farmers can now do and get a bit of money for.

Martin - So there's a whole range of things: it's planting more hedges, more trees. We are taking out some areas of the field and putting herbal leys in, to build fertility up. Bringing animals back into the landscape to graze, to build fertility, so I can remove artificial or fossil fuel based fertilisers. And it's bringing that integrated approach - not all of the options are available for me as an arable farmer. So there's multiple options for livestock farmers and farmers in different parts of the country. It's like having a shopping basket and you walk along the aisles, picking up the items you want. Then as you get into it the next year you can add some more ambition and put some more items in the basket. And it's helping farmers look at it as a suite of options and stacking options onto your farm. So I'm growing food, I produce wheat, but I'm also providing habitat. I'm locking nutrients into my soil, adding carbon back into my soil, taking it from the atmosphere. And these are all multiple wins that we can stack benefits across my farm landscape.

James - Of the 280 or so practices, obviously we're not going to have time to discuss all of them, was there anything you thought particularly was missing or anything that would encourage this sustainable push that the government really wants farmers to take on but hasn't been included in the scheme?

Martin - I think taking a whole farm approach. We could choose as farmers to do one or two individual actions at one end of the farm, but do some not good practice at the other end of the farm, and we need to take a whole farm approach.

James - One thing that's been highlighted as a real plus of the new ELMS scheme is the fact that it is going to be a bit of a win for smaller farmers. I think it's something like up to 90% of the global grain trade is controlled by about four companies, and previously under the CAP, which was the European Union scheme, farmers were getting reimbursed for the amount of land they worked on. So is this now a win for the little guy?

Martin - I think it is and a lot of the little guys, smaller farms, have more farm edges and the previous scheme rewarded you for bit just in the middle, the new schemes reward you for those edges. So more small fields, more diversity actually those small farmers will get more income. Farmers with big large fields will see their income decline because they're not managing that natural asset around the outside. So I think it really does help support that smaller farm business.

James - In terms of any further improvements, maybe, or certain things you'd like to see? You mentioned the holistic way you'd like farms to be analysed...

Martin - One of the concerns we have with the way the announcements have gone and the way they value it, it's about income forgone. So some landscapes aren't actually producing a lot of food and have been reliant on the previous payment structure to underpin their business which means we only value it on its food production. Some landscapes won't have an economical model to be farmed and actually they need to be valued for the public good they deliver, particularly the uplands and the Dales and places like that where public really enjoy the access to the countryside. And that also comes to a cost of the business: trying to manage that landscape to get the public good. So government do need to focus around where is the value of the public good in the different parts of the landscape across the UK.

Ears of wheat

06:55 - Cross-breeding to boost crop yields

Converting crops like wheat from annuals to perennials could significantly reduce environmental impacts...

Cross-breeding to boost crop yields
Tessa Peters, The Land Institute

One striking aspect about the foods we tend to farm most often is that these plants are all annuals: they grow, fruit and die all within a single season. This means farmers need to re-prepare the soil and re-sow each year, which costs time, fuel and wear on machinery. This in turn adds to the production costs and makes income harder for farmers to predict: fuel and fertiliser prices, for instance, have skyrocketed this year. So wouldn’t it be nice if we could plant these crops once and then harvest from the same plants over a series of years? That’s what an organisation called The Land Institute are working on: by breeding high yield modern crops with perennial wild relatives to produces cereals that keep growing year after year. Tessa Peters…

Tessa - At the Land Institute, our goal is that you would have a crop that gets planted and then you would harvest that summer and then the following year you wouldn't have to go back and plant. You would simply harvest the grain that was produced the next summer. And for us, we want to see crops that are producing grain for at least three years.

Chris - Our farming ancestors though, have spent literally thousands of years choosing, evolving, selecting and breeding plants that are the cream of the crop that we grow at the moment. And they are annuals; they come up, they produce their seed and then they die. So you are saying you want to reverse all that and come up with plants that doesn't happen to? How?

Tessa - Yeah, very much that. We are trying to go back 10,000 years and say, okay, with new technologies, can we choose different crops or can we choose to cross different crops to make the grains that we've currently chosen (like wheat) into a perennial? The reason that we think this is possible is that we can go back and we can look at crops that have been grown by communities for thousands of years and we can say these have been grown primarily as forages, but they have good qualities. We know they can be cultivated, so let's look and see if we can develop those into a grain crop. Can we make selections for things like bigger seed size and free threshing abilities so that we can make sure we can use them for different things like flour? And we believe that this is possible because we have folks who have selected perennial rice in Yunnan China. They've been really successful at producing perennial rice.

Chris - What's the starting point? Do you start with the perennial and then try and breed the characteristics of what we've got the best of the annuals into it? And what are those perennials? Are there cereals that you are basing this on that do come up year after year after year?

Tessa - We approach this from two different ways. We have a perennial program where we're looking at annual crops, sorghum, wheat, and rice. And then we cross them with a perennial relative, for example, for perennial wheat, we cross it with intermediate wheat grass and we try and keep everything that we like about the wheat. We like the big seed size, we like that it's easily harvested, that it doesn't shatter, it doesn't fall off the stem before harvest, those kinds of things. But then we want to bring in all of the perennial characteristics that we really like: the ability to overwinter and produce grain that next year.

Chris - When one grows perennials in the garden, you generally find that they're good for a few years and then they clap out and most gardeners tell you that's the time to chew them up and you replace them. So how long do you think you can extend the life cycle of some of these wheat plans? In other words, how many times do I end up not plowing a field and therefore saving on the fuel, saving on the tyre wear and everything else that goes into tilling a field so that I get the same sort of yield without all those other costs and the cost of the soil?

Tessa - Our goal is at least three years. We know that these are herbaceous perennials and they probably will have to be replanted. But for wheat, that's a third as many passes across the field with your tractor. Perennial rice has been in the ground now in China for eight harvests. It's two harvests a year. So that's four years.

Chris - And what are the yields looking like?

Tessa - For perennial rice? The yields are equal to annual rice. For some of the other crops that we work on, the yields are substantially lower, so about a third to a half of the wheat yields. And so the goal for us is of course to increase the yield through plant breeding and hopefully at some point rival the yields of wheat.

Chris - Are there any problems with something being in the ground for longer? That's more opportunity for pests to attack it, it's more opportunities for the plant to weaken for other reasons and dent yields further. So how are you building in safeguards against those?

Tessa - One of the things that we're finding is that perennial crops also have defenses that make them more resilient to disease in some cases. And that's how they've evolved so far. We haven't really run into any really big disease issues.

Chris - And the main sort of bonuses here, apart from the fact that you are breaking the link between a farmer having to buy seed every year to plant. But that means as well as your fuel savings of not having to run a tractor across that land, the soil is also a beneficiary because you are not getting soil erosion because you are not turning it over, you're not exposing the interior of the ground to the air and getting various erosion events and loss of nutrients and so on.

Tessa - Yeah, that's definitely one of the big advantages with a living root in the soil. The soil is being held by that living root and also by all of like the microbial and fungal interactions that are happening in the soil. Those microorganisms also secrete a lot of chemicals that help hold the soil in place and hold it together. So they also increase infiltration because the roots are penetrating the soil. And so when it rains, a lot more of that water is actually making it into the soil versus just running off and carrying the top soil with it. Another really important aspect of this is that these perennials tend to have much larger root structures than annual crops. This big root structure increases the amount of carbon that's stored in the soil. It can also scavenge nitrogen that's available in the soils and getting it out of the system and out of the water supply that humans are then using to drink. These crops tend to also be fairly resilient to drought because they have these long root structures that can source water from deeper in the soil profile. So there are a lot of benefits to having a perennial in the ground from reducing the number of passes that your tractor has to make to improving the soil and water quality.

Nodules on roots

13:15 - Peas provide promise for fewer fertilisers

Can the nitrogen fixing abilities of peas be transferred into other crops?

Peas provide promise for fewer fertilisers
Giles Oldroyd, University of Cambridge

Crossbreeding is one way to get crops to produce better yields, but it’s not the only way. And scientists at the University of Cambridge are approaching the issue from a slightly different angle. Giles Oldroyd is the director of Crop Science Centre where they’re engineering grain plants to take advantage of naturally occurring interactions with microorganisms in the soil, in the same way legumes like peas do.

Chris - Giles, do tell. What have peas therefore got the corn, wheat, barley, et cetera, doesn't.

Giles - Yes. So peas and beans have learned to engage with these nitrogen fixing bacteria that can colonize the roots of the peas, and they're able to convert nitrogen from the atmosphere into a reactive form of nitrogen that plants can use and then incorporate into amino acids, proteins, DNA, and RNA, et cetera.

Chris - How good are they doing that, Giles? As in, if you compared a bag of fertiliser and a pea plant, how much better is the fertiliser than the pea or vice versa?

Giles - Well, the pea plant doesn't need any fertilisation, so that's how good they are. They get all of their nitrogen from the air through this interaction with the bacteria. And if you compare that to a wheat or maze, you're getting most of the nitrogen through fertiliser application.

Chris - And your goal then is to say, well, we learn how the pea does it, we then borrow from the biology and we endow the wheat with the way the pea does it.

Giles - That's right. So for the last 20 years, myself and many others in the research community have been trying to understand how peas are actually engaging with these nitrogen fixing bacteria and identifying the genetic components that are present in peas and beans that allow them to recognize the bacteria in the soil and attract those bacteria into those roots, and then also create the environment for nitrogen fixation.

Chris - Would this be genetic engineering?

Giles - Correct.

Chris - And then you take the genetic elements from the pea and insert those into the wheat so that it can produce the right sort of factors and environments. So those microorganisms that are there get recruited into the wheat roots.

Giles - That's right. So we now have a really good understanding of how peas are able to engage with these nitrogen fixing bacteria. We know pretty well, at least a lot of the genetic components that are involved in that process. And so now we're in the process of putting those genes from taking them from peas, putting them into our cereal crops and trying to get our cereal crops to engage with these nitrogen fixing bacteria. Such that we can grow those cereal crops without the need for adding nitrogen.

Chris - Does it work?

Giles - We are in the process of doing it, so we just got the money to do that, to do all of that engineering. We've been working for a long time using funds from the Bill & Melinda Gates Foundation to understand that process in legumes. And we're really now pushing into that sort of product concept of how we actually make that system work and get the cereals to actually fix their own nitrogen.

Chris - I suppose that if you are able to do this and plants effectively become self fertilising, it means we are dosing soils less, which has got to be good for farmer's pockets. It's gotta be good for the environment. But it presumably also means that people who live in areas where the soils are naturally poorer and would have to use more fertilisers, presumably they're gonna be extremely pleased with your work because it means that they'll get a better yield out of their crops too.

Giles - So when we look at nitrogen, it's like a two-sided coin. Here in high income countries like the UK and particularly here in Cambridgeshire, we are applying fertilisers at high concentrations to support our crop productivity. That's essentially the green revolution and that green revolution, which allowed us to apply these nitrogenous fertilisers. It's tripled the yields of our cereal products. So we are really heavily reliant on the use of inorganic fertilisers to maintain our crop production. But the use of those fertilisers is very polluting. It's one of the major pollutants deriving from agriculture, both washing into our aquatic systems and causing biodiversity collapse, but also causing greenhouse gas emissions. So here in the UK and then for instance here in Cambridgeshire, if we could stop using those nitrogenous fertilisers have a much more sustainable way of growing our food. On the other side of the coin, if you look at much lower income countries like Sub-Saharan Africa, the farmers there don't have the financial resources to buy these fertilisers. And because of that, their crop production is really atrocious. I mean, we're talking about 20% of the potential production that they could actually be achieving, in part because of the lack of these inorganic fertilisers. So we can find ways of getting nitrogen into those systems, and particularly sustainable ways of getting nitrogen into those systems. We can massively raise up crop production for smallholder farmers. So really, if we can make this work, it could be truly transformative of our food production systems. Driving sustainability in high income countries and driving equity of global food production, particularly for smallholder farmers.

Chris - And just in the last minute, will this work everywhere? Because if the microbes are coming out of the soil and forming those relationships with pea plants, if you try and grow plants in places where peas wouldn't normally grow, will it work? In other words, are these microbes sufficiently universal that if you go and plant your modified plants in sub-Saharan Africa, those, uh, bacteria are there and the plants can use them?

Giles - So we know these nitrogen fixing bacteria are ubiquitous in soils across the world. But there are specialized bacteria that associate with peas and different bacteria that associate with beans. So it might be that you'd have to use inoculants and certainly in soil production in the US they're using inoculants. But once you've used those inoculants and got that, you actually plant the seed there.

Chris - That's where you physically add the stuff to the soil.

Giles - Yeah exactly. You plant the seed and you bring the bacteria with it. But often when you've done that inoculation, those bacteria then present in the soil and they're maintained in the soil. So you don't have to inoculate every year the bacteria reside within the soil and the next time you plant the, the crop, the bacteria there, the crop can find them and form that nitrogen fixing back association.

A cow grooms a calf by licking it on the neck.

Food production from farm to factory
Pasi Vainikka, Solar Foods

So far, we’ve been discussing how traditional, arable farmers can adapt to help the environment, whether that be through maintaining their farm with sustainable methods, or growing crops which are better adapted to produce yields without harmful and expensive fertilisers. But that still leaves the problem of the emissions from meat and dairy farming which many scientists argue must be reduced if we are to achieve our climate targets. Finnish company Solar Foods think they have the solution.Their approach is something more radical: moving food production from the farm to the factory. They do this by growing protein and fat rich food using bacteria that are themselves fed on a diet of carbon dioxide and hydrogen produced sustainably from water using solar-generated electricity. I spoke to CEO Pasi Vainikka to find out how…

Pasi - The main feed stock are the organism that is a single cell, hydrogen gas that we make from water (electricity used to make hydrogen from water and carbon dioxide.) And basically the bio fermenters are like a big soda stream. The whole cell biomass that we grow is our product. It's a dried powder.

James - Traditional agriculture has the problem of land use. Moving food production from farm to factory removes that problem. And the process, as you've described, doesn't take up lots of water, it doesn't harm the soil. So are there any real barriers to scaling this up to essentially solve food security?

Pasi - Not really. So for a food tech company, there are three things that you need to prove. You need to show that it's safe. The second is, are there nutritional benefits? How does it work technically? Does it form a structure? Structure forming is about how a glass of water differs from a jar of yogurt - that's texture. It's thick. So that is what you need. And the third one is does it scale? And that's where we are now. That's why we are investing in our first factory to prove that it really scales. We think of how quickly this food tech transition can happen. The unfortunate fact is that it's a huge industrial operation to get these factories built, and it takes time: two years per factory. So it's a scaling problem for the industry after we have proven the initials which we think we've already done.

James - I can appreciate that. Let's take that issue of the nutritional value of the product for a second. What can someone consuming this expect to extract?

Pasi - The simple answer is to think of it as a meat in powder form. So it is a complete protein. It does have all the essential amino acids, plus it contains three things typically an extreme vegan diet is lacking, which is iron, b12, and carotinoids turning into vitamin A. So it could serve as a main bulk of protein, but also what they call fortifier. So adding these vitamins and iron to a mostly plant-based diet.

James - It's obviously not consumed in the powder form, is it? How does it integrate with and how do you fuse it into the food or the texture that people are expecting when they consume food?

Pasi - Using some simple examples, everybody understands the concept of wheat flour. You buy that from a supermarket, but you hardly ever consume it as such, right? So you make it to different kinds of textures like bread. So whether it's meat alternatives, it can have different kinds of drink applications to shakes, to yogurts, ice creams, dairy alternatives, vegan mayo, and also replacing egg in some pastry, noodles, pasta. Not to forget the standard protein bars. So it's actually quite versatile in use and application, this ingredient.

James - So once you satisfy the criteria of making sure the nutritional values there, as you have, or the scaling will work, is the sky the limit here? What possibilities do you hope for once you get the all clear and you're able to start selling this product?

Pasi - On top of, from a scientific perspective, disconnecting food production from agriculture, we could also think about, on a food production system level, like it or not, if you look at planet Earth, what we need to achieve as humankind is to more or less remove animal keeping from this equation. Because 80% of the environmental impact due to what we eat is due to industrial, animal keeping. So we need to significantly reduce that. Maybe not get rid of completely, maybe rather not, but limit and maybe set in decline the volumes that we are practicing there. So that is something we and companies like us are to do here.

James - Food evokes strong emotions, let's say. Have you encountered ever perhaps a psychological barrier with people hearing about your work and hearing that you are producing food in a factory from essentially bacteria?

Pasi - There are a couple of approaches actually that you can take here. So the first is consumer acceptance. We've actually done some studies around the acceptance and once people understand that there are benefits for the environment and there are nutritional benefits, actually people are quite open to new opportunities because there haven't been completely new kinds of foods around, right? So it's actually intriguing to think that one could be part of the solution rather than the problem. So eating environmentally friendly food is an act for good.

James - It makes a lot of sense as to why the product you've got has got a lot of protein in it and a lot of fat because I think it's something like a third of the world's protein supply currently comes from meat and dairy which, as we know, and as you've mentioned, is one of the most resource intensive types of agriculture. So I can see why your aim has been to reduce the dependency on meat and dairy, but could different bacteria or different inputs be fermented in order to produce food products with other nutritional makeups? Are there other possibilities in this process?

Pasi - In answering that we open a kind of Pandora's box in the sense that there are so many opportunities through technology that almost anything is possible with time. What I mean is that cultivated meat is one specific application. What we are doing is that we are cultivating a microorganism. We don't modify it. So basically the composition of that organism is what it is. It's the same as the composition of you and me. Roughly speaking, you can't influence that too much unless you go into genetic engineering. And then new windows open for opportunities basically to tailor the organism to produce any protein that you want. We are a non GMO product today, but of course there are the GMO opportunities in the future basically to produce proteins, fats or flavours, colours, whatever. There are a lot of companies working on that.


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