Make cassava more nutritious

Emerging Food R&D Report, August, 2005

The Ohio State University will lead an interdisciplinary team of scientists in a multi-million dollar project to help improve one of the most important food crops in Africa--cassava. The Bill and Melinda Gates Foundation selected the BioCassava Plus Project as a recipient of one of the foundation's Grand Challenges in Global Health program grants.

Leading the $7.5 million, 11-institution cassava project is Richard Sayre, a professor of plant cellular and molecular biology at Ohio State. The grant runs for five years. Cassava--Manihot esculenta--is the primary food source for more than 250 million Africans, about 40% of the continent's population. And the plant's starchy root is a substantial portion of the diet of nearly 600 million people worldwide.

Cassava is the fourth-most-important crop in the tropics, and it's relatively easy to grow in drought conditions. The researchers will work on developing new types of cassava plants that have more zinc, iron, protein and vitamins A and E, and that can also withstand post-harvest deterioration.

But there are downsides to cassava. Its roots are low in protein and also deficient in several micronutrients, such as iron, zinc and vitamin A. And once the roots are harvested, certain strains of cassava can produce potentially toxic levels of cyanogens--substances that induce poisonous cyanide production. Sayre's laboratory is working on ways to decrease or eliminate cyanogens in cassava roots.

Through the BioCassava Plus project, scientists will increase the root's nutritional value, its shelf life once harvested (cassava roots deteriorate in about two days unless they are properly processed after harvesting) and its resistance to geminivirus, a devastating plant virus that can destroy up to 60% of a cassava crop.

Among the researchers working on the project are 18 scientists from 10 institutions including Ohio State; USDA-ARS; the Danforth Plant Science Center, St. Louis, MO; Washington University Medical School, St. Louis; the University of Bath, U.K; and the International Center for Tropical Agriculture, headquartered in Colombia.

Further information. Richard Sayre, The Ohio State University, Department of Plant Cellular and Molecular Biology, 520 Aronoff Laboratory, 318 W. 12 Ave., Columbus, OH 43210; phone: 614-292-9030; fax: 614-292-6345; email: sayre.2@osu.edu.