The founder and chairman of Microsoft and co-chair of his philanthropic endeavour, the Bill & Melinda Gates Foundation, was speaking at the World Food Prize Symposium in Des Moines on Thursday.

To date, the foundation has committed $1.4 billion to agricultural development efforts.

Gates warns that the global effort to help small farmers is "endangered by an ideological wedge that threatens to split the movement in two."

One side is a technological approach that increases productivity, while the other is an environmental approach that promotes sustainability, he says. Yet both are needed, and there is no reason why both can't be used.

Compared to the first Green Revolution in the 1970s, the next revolution needs to be greener than the first - guided by small-holder farmers, adapted to local circumstances and sustainable for the economy and the environment, he says.

This year's World Food Prize Laureate winner, Dr. Gebisa Ejeta, says Gates' dedication to helping alleviate world hunger brings two important things to the cause: capital and the trust and credibility that comes with the Gates name.

Ejeta, a renowned Ethiopian sorghum researcher, was given the award for his work to develop hybrids resistant to drought and the Stringa weed - advances credited with increasing food security for hundreds of millions of Africans.

Gates also laid out nine grants totaling about $120 million that his foundation will use to serve small farmers and span the value chain.

These grants include funding for legumes that fix nitrogen in the soil, higher-yielding varieties of sorghum and millet and new varieties of sweet potatoes that resist pests and have a higher vitamin content.

Other projects will help the Alliance for a Green Revolution in Africa support African governments in developing policies that serve small farmers, help get information to farmers by radio and cell phone, support school feeding programs, provide training and resources that African governments can draw on as they regulate biotechnologies and help women farmers in India manage their land and water resources sustainably.