Africa's small farmers, more than half of whom buy their seeds from local informal markets, need access to improved seeds that can yield more food and cope with climate change, according to research published on Wednesday.

Innovations in food science, including seeds that produce vitamin-rich food and crops that can withstand the hotter, drier conditions due to global warming, are not reaching many of Africa's small farmers as they are not available in local markets, researchers said.

The study, published in the journal "Food Security", examined 10,000 seed transactions across five African countries and Haiti, and researchers said it shed light on how food production can be expanded.

"Science is making improvements to crops, but they are not getting to farmers," Louise Sperling, senior technical adviser to Catholic Relief Services who worked on the study, told the Thomson Reuters Foundation.

"Products farmers might want to choose, (including) varieties that are better resistant to climate change, aren't accessible."

Previously, many researchers assumed that small farmers relied on saving seeds from previous harvests, rather than purchasing them.

But the study showed that about 55 percent of small farmers in Kenya, Malawi, South Sudan, the Democratic Republic of Congo and Haiti bought their seeds from local markets, family or friends.

"The good news here is that (small) farmers are active customers," Sperling said.

SMALL FARMERS OPEN TO CHANGE

This means many growers would be open to buying better, climate-smart seeds, if they were readily available in small, rural markets and appropriately marketed, she said.

Large seed dealers generally focus on selling large volumes to institutional clients, such as big aid agencies or the United Nations, rather than small farmers, she said.

Companies should offer smaller seed packages to farmers, and should inform them of new kinds of seeds which might benefit them, she said.

Social enterprises could play a role in improving rural distribution networks if traditional dealers are unwilling to serve poor customers in remote areas, Sperling said.

Small farmers, working on less than two hectares of land, produce up to 80 percent of sub-Saharan Africa's food, according to the U.N. Food and Agriculture Organization (FAO), and ensuring they have access to the right seeds is crucial for reducing hunger.

Nearly 800 million people worldwide do not have enough to eat, and sub-Saharan Africa is particularly hard hit, the FAO has said.