San Francisco  - Tech billionaire Bill Gates pledged 120 million dollars Thursday to programmes aimed at helping small farmers in Africa and India grow more crops and develop sustainable agricultural techniques.

"Three-quarters of the world's poorest people get their food and income by farming small plots of land," Microsoft co-founder Gates said in a speech to the World Food Prize Symposium in the Midwestern US state of Iowa. "So if we can make small-holder farming more productive and more profitable, we can have a massive impact on hunger and nutrition and poverty."

The grants, which will be made by the Bill and Melinda Gates Foundation, will educate African farmers about the benefits of growing certain crops such as legumes, which fertilize soil, and varieties of sweet potato that can help eradicate Vitamin A deficiencies in children.

The grants include 15 million dollars to Nairobi-based Alliance for a Green Revolution in Africa (AGRA) to develop policies that would improve farmer productivity, expand markets for crops and strengthen property rights. Some 12 million dollars will go to help farmers supply local school-feeding programmes; 10 million dollars is earmarked for a farmer radio network in Kenya, Malawi, Zambia, Mali, Ghana and Tanzania; and 9.7 million dollars would help rural families in India by mobilizing 120,000 women and training them in land and water management.

The foundation is also donating 4.7 million dollars to the Grameen Foundation to build a system for communities in Uganda to use mobile devices to exchange agricultural information.

Gates also called for an end to the battle between groups who disregard environmental concerns and those who discount productivity gains. Citing growing populations and the effect of climate change on reducing harvests he said, "The fact is, we need both productivity and sustainability - and there is no reason we can't have both." dpa