Science’s role in growing diverse, nutritious food
- There will be ten billion mouths to feed by 2050, so food production must rise
- Science can offer tools and strategies but policies must change, too
- In particular, ways to get science in the hands of farmers are vital
The riots that swept Africa in 2007 and 2008 in response to the spiralling costs of staple crops brought the effects of food shortages into sharp focus.
Images of unrest circled the globe, and the consequent instability brought to the forefront of political debate a question that had long been out of the spotlight: how can we ensure everyone has access to enough safe and nutritious food?
Food security is an issue that touches all aspects of the development agenda, from agriculture and environmental management to economics, governance and social equality. It is also a challenge with no simple solution.
But one thing is clear. If food production is to rise by 70 per cent by 2050 to feed the rising population, as the UN Food and Agriculture Organization (FAO) predicts it must, we must do more with less.
How to achieve this jump in food production sustainably is “one of the big questions of our time”, says Sieg Snapp, a professor of soil and cropping systems at Michigan State University in the United States.
An estimated ten billion people will live on Earth by 2050. The increase in food production needed to feed them must be achieved while the resources to grow food are squeezed by urbanisation, environmental degradation and competition for land from biofuels and livestock.
During the Green Revolution of the last century, science and technology had a transformative effect on agriculture.
But in the 21st century, are they still the key to long-term food security?
Or will solutions to food insecurity be found in deeper structural, political and social change?
Cereals just don’t cut it
Over 2.3 billion tonnes of cereals are produced every year, according to the FAO. They are responsible, either directly or indirectly though animal feed, for the bulk of calories humans consume.
Wheat, maize and rice alone are responsible for almost half of the calories and 40 per cent of protein consumed in the developing world, says the FAO.
Snapp says that though cereals may be agricultural heavyweights, there is growing recognition that they alone cannot be relied upon to feed the world.
Traditional measures of food security focus on access to calories, and so do not acknowledge the importance of consuming a range of nutrients, she adds. Instead, says Snapp, they
“If the world continues along a mono-crop trajectory there will be serious impacts on environmental, food and nutritional security.”
Sieg Snapp, Michigan State University
prioritise monoculture systems aiming to maximise cereal yields, and lead to diets lacking a variety of proteins and micronutrients.
“If the world continues along a mono-crop trajectory there will be serious impacts on environmental, food and nutritional security,” she tells SciDev.Net.
The most important step towards improving people’s diets, especially poor farmers, is to encourage them to produce a range of crops on each smallholding, as well as different varieties of each crop, she adds.
African farmers growing a mixture of nitrogen-fixing crops, such as soybean, peanut and pigeonpea one year, followed by just maize the next, achieved similar grain yields to monoculture maize but with 50 per cent more protein content, and using half the fertiliser, her research has shown.
Furthermore, farmers with access to a range of modern and traditional crop varieties will be more able to deal with environmental stresses, such as drought or flooding, that are set to increase as the climate warms, according to Snapp.
Science has a role to play in honing and disseminating these strategies, but a lack of political support can prevent them from becoming more widespread, she says.
“Crop diversity on small-scale farms is vital to meet nutrition, food security, medicine […] needs, and deserving of much greater attention from policymakers and scientists.”
Or does diversification come later?
Diversifying crops is important, but the research focus should not shift from improving the “pillars of food production”, says Hans-Joachim Braun, director of the Global Wheat Program at Mexico’s International Maize and Wheat Improvement Centre (CIMMYT).
Growing cereal crops more efficiently is paramount to freeing up land to grow more other crops without reducing the total calories produced, he says.
“We have to increase production [of cereals] much faster than population growth — only then can we diversify the cropping system to the extent needed,” he tells SciDev.Net.
Science is also vital for improving the quality, not just the quantity, of cereals by increasing concentrations of micronutrients such as zinc and iron, he adds.
Hidden hunger — caused by a lack of micronutrients — cannot be solved solely by crop improvement, Braun admits, but given that the biofortification programmes of many developing nations have failed, it can go a long way.
Animals are another important source of nutrients, but as people the world over eat more meat, finding efficient ways to raise livestock that do not compete with other forms of agriculture is a priority.
One innovation in this respect is genetically modified cotton which has seeds free of a toxin that usually prevents protein-rich cotton seed waste from being used as a feed in aquaculture, and pig and poultry farming.
If the method was deemed safe for human consumption, the international team behind the research believes it could satisfy the protein needs of 500 million people.
Researchers are also exploring other options, from developing techniques to raise insects on food and human waste, to growing protein tissue in labs.
Science is key, but so are policies
Achim Dobermann, deputy director-general for research at the International Rice Research Institute (IRRI) in the Philippines, agrees that research programmes for crop improvement are essential for future food security.
To date, however, genetic improvement has largely focused on specific genes or pathways regulating traits such as pest resistance or grain size. But researchers must aim for more ambitious targets involving multiple genetic pathways, he says.
Boosting levels of photosynthesis, the process by which plants turn sunlight and water into food — as current IRRI and CIMMYT projects are attempting — or giving nitrogen-fixing abilities to cereals could lead to “quantum leaps” in yield and efficiency, he believes.
But these ‘blue-skies’ strategies can take decades to bear fruit, and so other technologies should be developed to fill the gap, says Dobermann.
In the developing world, technology to keep food edible after harvest, such as equipment to dry grains and store crops, needs more development, he adds.
According to a joint report from the FAO and the World Bank, inefficiencies in grain processing and storage in Sub-Saharan Africa alone could cost the region US$4 billion a year, or around 15 per cent of total production.
Great steps could be taken towards improving food security using existing technology and knowledge, says Dobermann.
But policies, including long-term fertiliser subsidies and poor land-tenure rights, often discourage farmers to adopt alternative strategies. These must be reformed to stimulate innovation, access to new technologies and a vibrant business sector, he adds.
“This [political will] is the bottleneck — the situation will not get better if this sticking point is not removed.”
In developing countries, the ‘extension’ systems that bridge the gap between labs and farmers' fields are often weak, forming major obstacles to the diffusion of scientific knowledge, says Dobermann.
“I am often frustrated by how little adoption there is of proven technologies, resulting from the lack of a motivated and well-resourced extension work force,” he says.
Spreading the word
Traditional state-led extension activities tend to focus on promoting specific seed varieties or techniques, rather than more holistic approaches to increasing yields while protecting the environment.
CIMMYT aims to change this by supporting existing knowledge hubs in Sub-Saharan Africa and Mexico. These provide farmers with information on seeds, agronomy practices and machinery.
Organised through meetings, workshops and, increasingly, mobile phones, these hubs allow farmers to pick and choose solutions to the problems they deem important.
How to get scientific knowledge to those who need it is a central question of the food security debate — but one which is overlooked, says Shaun Hobbs, global director of Plantwise's Knowledge Bank, a global initiative to disseminate knowledge on plant pests and diseases.
“There is a real thirst for knowledge at the level of the subsistence farmer but generally it is very difficult for them to access it.”
Shaun Hobbs, Plantwise
“There is a real thirst for knowledge at the level of the subsistence farmer but generally it is very difficult for them to access it,” Hobbs tells SciDev.Net.
Plantwise combines traditional knowledge and scientific approaches to create a large online and offline database of diseases and their solutions. The project is also training local extension workers in 31 countries in how to recognise and treat plant diseases, and then spread this knowledge to local farmers through ‘clinics’ in local meeting places.
It’s difficult to evaluate the impact of the initiative, but the initial signs are extremely promising, says Hobbs.
For example, farmers in Bangladesh report an increase in income and crop yields of 24 per cent and nine per cent respectively after visiting the clinic, he says.
The explosion of digital technology offers “huge potential to amplify the message” and to widen the scope so that every farmer has access to the information to make informed decisions, he says.
As a multi-faceted issue, there will probably never be a silver bullet to ensure food security. But finding innovative ways to spread knowledge, paired with continued support for research, seems set to ensure that science will remain a crucial weapon in the years to come.
This article is part of the Spotlight on Ensuring food security for the future.