Gary Toenniessen Addresses Council of Science Editors
Biotechnology and Plant Breeding Are Key to Alleviating Hunger and Rural Poverty in Africa and Asia

“Working Toward a Sustainable, Equitable World” was the theme of the Council of Science Editors’ annual meeting, held May 20–23 in Tampa, Florida. In his plenary address, Gary Toenniessen, director of food security for the Rockefeller Foundation, emphasized the role of plant breeding in solving problems of hunger and poverty. He stated that most poverty in Africa and Asia results from low-productivity farming in these largely agrarian societies, resulting in a lack of income.

He first described how the Asian Green Revolution—the introduction of semi-dwarf, high-yielding varieties (HYV) of rice and wheat—increased both labor productivity and the demand for labor. The HYV require greater inputs (fertilizer and irrigation) than do traditional varieties to produce the higher yields; they are true-breeding (so farmers could save seed); and they are early-maturing, often ready for harvest in 100 days rather than the 160–180 days required by traditional varieties. This means that farmers can plant two or three crops per year instead of just one, which enables the labor force to work throughout the year. The use of fertilizer and irrigation also allows one or a few varieties to be used in many different locations. These and other factors combined to benefit those farmers (both large and small), consumers (who then pay lower prices), landless laborers, input suppliers, and output purchasers, resulting in significant benefits to the overall economy.

These benefits, however, have bypassed many farmers who did not adopt the HYV and who remain in poverty today. These are farmers who lack the means of irrigating their lands and are dependent on rainfall or limited supplemental irrigation and include some of the agrarian population in Asia and most of Africa. These farmers continue to plant traditional varieties because they are drought tolerant, whereas the HYV are not. A rainfall-dependent farmer who plants HYV risks complete crop loss when the rains don’t come.

Toenniessen described how advances in plant breeding and biotechnology are being used to develop new crop varieties that are drought tolerate and that yield as well as the HYV when the rains are good. He also explained how biotechnology is being applied to difficult traits such as weed control. For example, Striga is a parasitic weed that attaches to maize roots and results in severe yield reduction throughout Africa. A naturally occurring maize mutant resistant to the herbicide imidazoline has been developed into a new variety (StrigAway®) that can restore maize production under Striga-infested conditions to normal levels.

Some of the big challenges in Africa, which The Rockefeller Foundation and others are working to address, are in building the capacity for biotechnology and plant breeding and in building the input and output markets. When the Green Revolution began, Asia already had in place a vast system of irrigation and a foundation in biotechnology, both of which are lacking throughout much of Africa today. Africa is largely dependent on rainfall, and a new Green Revolution is needed that follows a “niche-breeding” approach, aimed at the development of many new crop varieties that are fine-tuned to local environments. This approach focuses on limiting yield losses (under extreme environmental conditions) rather than “increasing yields.” Building the capacity for biotechnology includes training plant biologists and breeders, and Toenniessen estimated that Africa needs at least 1,000 Ph.D. plant breeders working throughout the continent.

Toenniessen described his image of success in Kenya: a farmer with just one hectare, who is able to acquire and use new fertilizers and varieties to produce maize on one-half of her land, some of which she is able to sell at a good price and some of which goes to feed livestock that she keeps on another quarter of her land, and in the remaining quarter she is able to grow vegetables for her family and for market. Many steps will go into making this a reality, but the first step is to boost the productivity of maize for this farmer—in her local non irrigated environment. For further reading, see Toenniessen et al. (2003), Curr. Opin. Plant Biol. 6, 191–198.

Nan Eckardt
neckardt@aspb.org