Feeding Africa

BEFORE TOUCHING down in Cape Town just after dawn one day last month, my flight cut across Namibia and northwestern South Africa. Out my window I watched the clouds give way to inhospitable-looking expanses of sand marred by jagged, rocky scars. I wondered how anyone could grow anything there.

In fact, Africa is the only region in the world in which average per capita food production has fallen steadily over the past 40 years, according to the United Nations Food & Agriculture Organization (FAO). The situation is particularly precarious in sub-Saharan Africa, where poverty, nutrient-depleted soil, and an unruly and unpredictable water supply have left millions of people unable to feed themselves.

I had come to Africa in December for the International Union of Pure & Applied Chemistry's Chemical Research Applied to World Needs (CHEMRAWN) XII meeting. Here, in a leafy college town outside of Cape Town, I joined scientists from all over Africa and around the world to discuss the role chemistry will play in ensuring a sustainable food supply on the continent.

Participants offered a number of creative chemical solutions aimed at sustaining water and soil quality, increasing crop yields, and preventing postharvest food loss. For example, Salome M. Guchu and her colleagues at the International Center of Insect Physiology & Ecology (ICIPE) in Nairobi have characterized the natural chemical weaponry that Desmodium legumes use to thwart the growth of the parasitic witch weed plant, an enemy of Kenyan maize farmers. ICIPE scientists are now collaborating with U.K.-based Rothamsted Research to screen related legume species for those that have the highest concentration of the most active glycosylated flavones. They hope to convince Kenyan farmers to plant such legumes alongside their maize to prohibit witch weed growth and protect their crop.

But is food security in Africa really a problem that requires a scientific solution? "The cynical answer is yes—if you want to attract research funds," argued Martin Fey, a geochemist at Stellenbosch University, which hosted CHEMRAWN XII. "But the real answer surely lies elsewhere. There are many constraints on food security in Africa, the least of these being scientific knowledge."

Fey's point is bolstered by Malawi's recent transformation from food-aid recipient to food-aid donor. Just three years ago, the perennially poor and hungry country was scorched from drought and as many as 5 million of its citizens relied on foreign-supplied food aid to survive. In 2006–07, however, Malawi provided 10,000 tons of food aid to Lesotho and Swaziland.

Malawi's remarkable turnaround came not by way of some new scientific discovery, product, or advance but simply because the government made subsidized chemical fertilizers and good seeds available to its farmers.

Better rains helped the cause but can't explain the dramatically improved yields of those farmers who got the subsidies, argued Pedro Sanchez, an agronomist at the Earth Institute at Columbia University and an architect of the food component of the United Nations' Millennium Project, which is aimed at easing hunger, poverty, and disease among the world's poor.

EVEN THOUGH "you can buy a Coca-Cola just about everywhere in sub-Saharan Africa, you simply can't buy seed and fertilizer," Sanchez said. "Better rains are not enough when a nation suffers from critical deficiencies in soil nutrients."

Malawi's experience emphasizes that simply making fertilizers and better seeds more affordable and more widely available can lead to dramatic improvements in food production. "The Malawi success could be replicated by other countries facing a very difficult food production environment," FAO Director-General Jacques Diouf said at a press conference in Rome last month.

Later, I asked Sospeter Muhongo, regional director of the International Council for Science in Africa, whether there is at least some role that science can play in ensuring food security for the continent. "We should not be questioning whether science is key to improving Africa's food security," he told me. "Considering our existing food shortages and growing population, we must look to modern and appropriate science and technology—for example, biotechnology—to increase our food supply in the future."

Soaring food prices—driven by global biofuel production and droughts and floods linked to climate change—and war are further threatening food security across Africa. Indeed, the food security problem that Africa faces is so complex that it seems impossible that science won't have a role to play in solving it. But on a continent where most farmers can't afford fertilizer or high-quality seeds, rely on rain to irrigate their crops, and remain isolated from markets where they can sell their produce, science may be only a small part of the answer.