Two African plant scientists and two U.S. economists share the 2016 World Food Prize. Together, they have alleviated hunger by helping convince Africans to eat Vitamin A-rich orange sweet potatoes and by bringing other fortified crops to farmers and consumers in 30 countries.

The $250,000 award, created in 1986 and often called the Nobel Prize for agriculture, was presented in a ceremony June 28 at the U.S. State Department.

Three of the laureates are affiliated with the International Potato Center in Lima, Peru: plant scientists Maria Andrade and Robert Mwanga, based in Mozambique and Uganda, and economist Jan Low, the center’s regional leader for Africa.

The International Potato Center bucked the prevailing view that the best way to treat vitamin and mineral deficiencies was to give poor people capsule supplements.

The fourth 2016 laureate is Howarth Bouis, founder of HarvestPlus, which champions biofortification, an innovative breeding process to make a range of staple crops more nutritious.

Andrade, a Cape Verdean, and Mwanga, a Ugandan, are veteran researchers in plant breeding. Low arranged studies and organized a campaign that convinced almost 2 million households in 10 African countries to plant, purchase and consume orange sweet potatoes.

They worked with Bouis and HarvestPlus on the potato project from 2003 to 2010. Bouis and his HarvestPlus organization, following in the footsteps of the late Norman Borlaug, the father of the “Green Revolution,” have brought iron-and-zinc-fortified beans, rice, wheat and pearl millet to countries across Africa, Asia and Latin America.

The campaign is currently trying to convince African farmers to grow maize (corn) with deep orange kernels instead of white, Bouis said.

Kenneth M. Quinn, president of the World Food Prize Foundation in Des Moines, Iowa, and a former U.S. ambassador to Cambodia, announced the winners, who were saluted in a keynote address by USAID Administrator Gayle Smith.

Thanks to the laureates’ work, Quinn said, more than 10 million people today eat more nutritious food, “with a potential of several hundred million more … in the coming decades.”