The president of the Rockefeller Foundation says African scientists have made great strides in research to increase the continent's food quality and quantity. But he and others say these gains won't mean much if other technologies and land policies do not keep pace.

Rockefeller president Gordon Conway says Africa is going through its own green revolution, with a dedicated group of African scientists devising ways to keep plants safe from diseases and insect attacks and increase crop yields.

He says innovations include producing varieties of cassava - a common tuber crop in Africa - that are resistant to mealy bugs that destroy much of the crop. They have also come up with parasites that eat mealy bugs.

Specially bred banana plants in Uganda and other parts of east Africa can produce up to 90 tons of bananas a hectare, while in West Africa and Uganda, hybrid strains of Asian rice are growing well.

Mr. Conway says African scientists are now plunging into the controversial field of genetically modified, or GM, crops, with encouraging results.

"There's a whole new generation of bright, young Africans in plant breeding and in biotechnology that are showing the way," he said. "I went into the biotechnology laboratories which [Ugandan] President [Yoweri] Museveni opened only a year ago. Those young biotechnologists there are right at the cutting edge of GM transformation, in this case working on bananas."

He says scientists in Kenya, Zimbabwe and South Africa are also conducting leading-edge research. These innovations can potentially help many small-scale African farmers who cannot afford the prohibitive costs of fertilizer. For example, Mr. Conway says, a ton of urea that sells for $90 in Europe goes for $500 in Kenya and $700 in Malawi.

Yet, without fertilizers to keep plant diseases and bugs at bay, the agricultural yields of small-scale farmers can be cut by as much as half, perpetuating the cycle of malnutrition.

Despite the breakthrough innovations, says Mr. Conway, the amount of agricultural education and training taking place in Africa is small compared to what it should be.

"We cannot break out of the cycle of poverty in Africa without well-trained Africans, both in the social sciences and in the natural sciences," said Mr. Conway. "And we haven't been doing enough. World Bank expenditures on agricultural research, extension, and higher education in the decade of the 1990s [was] $5 billion. Only two percent went on training."

Another major problem in most African countries is land tenure. A southern and east Africa representative of the United Nations Food and Agriculture Organization, Victoria Sekitoleko, calls for African governments to come up with clear land ownership policies.

She says most Africans do not own the land they work on, which may give them less incentive to use the breakthrough innovations scientists have come up with.

She wants African governments to reallocate half of the $22 billion they spend on food imports to instead invest in agriculture so that they can produce and eat their own food.