Policymakers are going to need to take advantage of the full range of possibilities if they are going to meet the food security challenge. But encouraging people to domesticate local plant varieties is both simple and cost-effective, argues agroforestry expert Patrick Worms.
Patrick Worms is the Brussels-based Science Policy Adviser of the Nairobi-based World Agroforestry Centre. He spoke by telephone to EurActiv's Marc Hall.
The European Academies Science Advisory Council and the Network of African Science Academies recently joined forces in calling for more biotechnology in African agriculture. Do you agree and, if so, how do you think the continent should go about investing in biotechnology?
Ensuring food security for the 10 or 11 billion people that will soon live on a planet buffeted by climate change is a challenge which no single technological breakthrough will be able to meet on its own. We’re going to need everything. We’re going to need biotechnology; we’re going to need agro-ecology; we’re going to need agro-forestry; we’re going to need fertilisers and irrigations and tractors and whatever science human ingenuity can throw at the problem. We need all of it and any step that is taken to push that agenda forward is to be welcomed.
There are a number of different technologies or ways of operating, which can have benefits depending on the needs. That’s one of the things they [EASAC and NASAC] were saying, that scientists in Africa were developing solutions for local needs, such as crops with improved vitamin content…
Well in that case, I would be more cautious in the way that I express myself, and I would do that out of solid scientific principles. Literally thousands of plants have been recorded around the world as being eaten by humans. A very very small minority of those make up the overwhelming majority of crops. These crops, on which we all depend - maize, wheat, rice, that sort of thing - have already been engineered by farmers for thousands of years. They are very, very different from their wild ancestors, and have very narrow genetic variety left. It’s really hard to improve them further with traditional breeding. That’s why genetic modification is so tempting with them.
It is possible to do that, and it may be necessary to do that. But if we focus too much of our scientific and financial resources on that approach, we leave a much more effective solution on the table: doing the basic work of domesticating these hundreds of species that could be very valuable in ensuring food security and that are currently only harvested from the wild. Most of those are totally unknown outside of the area where they are consumed.
But some your readers will have heard about. Think of the baobab, that iconic tree of Africa. Its fruit and its leaves have nutritional profiles, in terms of their micronutrient and vitamin content, that put avocados or oranges to shame. In season, baobab fruit sellers are a common sight along African roads, so it is popular. And yet it has not been domesticated. It’s not being cultivated.
There are hundreds of examples like that. And the thing that fills me with hope is that when you are dealing with such a wild species, the genetic variability is much higher than it is with crops. That means it’s much cheaper and much easier to breed high-performing varieties than it is when you start with something like maize, which has already been engineered to within an inch of perfection.
… using different breeding techniques over generations?
That’s right. If I’m in Cameroon and I want to domesticate safou - imagine a small, electric-blue mango - all I have to do is go into a village and look at the 20 different wild safou trees out there, pick the best one, and multiply that by taking and growing cuttings. And boom, I’ve easily achieved a much higher improvement in the profile of that village’s food sources than I could ever have done by applying the most advanced and most expensive forms of biotechnology to maize.
So that’s another approach, involving agroforestry, your line of work…
Indeed. When we deal with issues like food security, micronutrient deficiencies, economic opportunities, land degradation or climate change in rural areas, we do so at the scale of landscapes. And in almost all landscapes outside the polar regions, trees within farms, trees on fields even, offer economic and environmental services that are astonishing in their breath and scope. We find that by taking that approach, we can usually hit multiple stones with a very limited intervention. Trees are a cheap technology, one that does not depend on fossil fuel inputs. Trees enhance soil quality and take carbon dioxide out of the air. They protect crops from extreme weather and from pests. Their leaves are fodder, their wood is timber and energy, and their fruits are nutrition. If there is any technology we cannot do without as we seek to feed the world, it is agroforestry.
Are you working directly with farmers and communities?
One of the jobs that we do as agro-foresters is to work with local communities to interest them in trees, and to improve the characteristics of the trees that they’re interested in. Take fruit trees. People usually want straightforward things: a tree that produces more fruit that are more resistant to pests, are sweeter, have more juice, or whose kernels are bigger, if you’re interested in the nut of that fruit. What the farmers really want is for a tree to fruit early. Many wild fruit trees need 10 or even 20 years before they carry their first fruits. But if you do a little bit of breeding, a little bit of selection, you can fairly rapidly get varieties that fruit after three or four or five years.
There’s huge untapped potential. I started off this conversation by saying that we need all of the above but there’s also a question of return on investment and the best return on investment you can get right now are these unexploited species. They are just waiting to be exploited and it’s a shame that we’re not doing more in that regard.
It’s also something that puts power in the hands of local communities of course. What we found in the country where we have the most experience of that particular kind of work, Cameroon, is that villages fairly rapidly select individual trees that are best for their given local circumstances. That means that those trees are adapted to their local weather, their local soil but also the local cultural and economic circumstances. And because it’s so easy to domesticate and to breed those trees at the beginning, you don’t need vast amounts of money or hordes of scientists.
You need some basic knowledge that you can give to the farmers, a little bit of technical support - you don’t need a lab in that village, you need a guy who drops by every two weeks - and you can help the farmers achieve huge progress with these very very simple tools.
… One or two modern techniques to add to what they already know. What about techniques for irrigation?
If you think about it, irrigation is crucial, but the problem with irrigation is that it demands capital and poor African farmers have no capital to start off with. So either you inject capital from the outside, which is what development aid does. That can work, but we all know that the amount of money available for development is not enough to meet the needs of the hundreds of millions of poor farmers around the world. So as the very first step, you need to figure out things that are very cheap in capital.
So, for example, let’s imagine that you have one of these food trees that produces a very sweet fruit in large quantities within three years of being planted but that needs irrigation because it just cannot cope without. It’s a bit fragile. It just cannot cope with extended periods of dry weather. But imagine you have another tree which produces food which is maybe a little less sweet ,and that takes a little bit longer to fruit, but is hardy. That’s the one that farmers will select, because they cannot afford to put in place the irrigation systems. That tree is not the sweetest, but it will make these farmers a bit more successful.
Now later on, when thanks to these first trees they’ve upped their income a little bit and have saved a bit of capital, they can afford to put in irrigation systems. Then of course it makes sense to go that way, and they will.
The whole thing is very dynamic. That’s exhilarating, if you think about it. You’re not going to develop one variety, like the gala apple, which stays the same for decades on end. You’re going to have hundreds of varieties that will blossom across the landscape, each adapted to its particular local circumstances. So at the beginning you’ll have the hardy varietal, later on, as the farming becomes more sophisticated you might have varietals that have other characteristics but that are less hardy. You see, when you think about it, it’s really beautiful, the whole thing moves completely dynamically, and that’s what’s gorgeous about agroforestry and agro-ecological systems! You do not come in with a preconceived idea of what will work in a given landscape. You work with what that given landscape offers you in terms of soil, in terms of water, in terms of weather, and in terms of biodiversity, in order to coax the largest amount of calories and nutrients out of that soil, sustainably.
Will it be enough, on its own, to feed the world? I would not presume to claim that. Let’s remember the scale of the challenge: we need to grow as much food over the next 40 years as we have grown over the past… 8,000 years! And we have to do that on roughly the same amount of land being farmed today, in a context of vast environmental changes. As I stated at the beginning, the only way we can do that is by using all it. We need the efficiencies of modern agriculture, the astonishing shortcuts of biotechnology, and the holistic management of landscapes of agroforestry and other forms of agroecological agriculture. We need to get beyond the confrontational debates that have characterised farming and work with all the tools at our disposal. The challenge is too large to be solved with a single magic bullet, even one has powerful as agroforestry.