Late blight resistant potatoes in Uganda promise impressive returns

Potato is a popular crop in Uganda with great potential for income generation and improving nutrition. So much so that the Ugandan government has declared potato a key crop for the country.

In Uganda, CIP partners with the National Agriculture Research Organization (NARO) to release and promote improved varieties of potato and sweetpotato and to grow national markets so distribution of these crops can reach intended beneficiaries.

Currently, 300,000 metric tons of potato are produced each year in Uganda, where farmers earn market prices ranging between 33-50 cents per kilogram (or USD 1,500-2,000 per hectare) depending on the season. Roughly 60% of the country’s potato crop is grown in the southwestern highlands (above 1,800m) that border with Rwanda and Congo. Another 20% is grown in the eastern part of the country around Mt. Elgon. Farmers can grow two crops of potato per year, except in the southwest where farmers have an additional season from July to September.

These impressive numbers, however, do not reveal the growth potential for potato in Uganda. Farmers currently average 7 metric tons per hectare, but with improved varieties and best farming practices, they could net up to 40 metric tons per hectare, according to Alex Barekye, a potato expert with NARO.

“From my perspective, I see potatoes changing lives in Uganda,” says Barekye, who specializes in crop breeding. “With the profits from potato, farmers can afford to build new homes. They use potato as a food security crop for their families. Nationally, potato has a plays a significant  role in feeding rising urban populations. The market is growing.”

While poor agronomic practices and declining fertility are perennial challenges to potato in Uganda, Barekye says the true to obstacle is late blight disease, which can damage between 40-60% of a harvest. Furthermore, farmers who spray to prevent late blight often do so without proper personal protective gear, thus exposing themselves to fungicides.

At the moment, purchase and frequent use of expensive fungicides is the only protection available to farmers. Aside from their cost, the application of fungicides is time consuming and backbreaking work. Carrying a 30kg container to spray their field is drudgery.

But Barekye, with assistance from CIP, is working on a solution to late blight by developing a potato variety with natural resistance to that disease. They are working the Victoria potato, a variety released by NARO in 1992.

Through biotechnology tools, NARO and CIP have developed a new version of the Victoria variety by adding three resistance genes (3R). Barekye and his colleagues have tested this 3R Victoria variety, which is showing complete resistance to late blight in field trials. In those trials, the 3R Victoria was compared with the original Victoria and exposed to natural infestation. The Victoria potatoes were infected by late blight after nine weeks and were completely wiped out by the eighteen week. Comparatively, the 3R Victoria potatoes were healthy owing to their complete resistance to the disease.

However, these early results must be replicated and examined by Uganda regulatory agencies before market release is possible.

The release of 3R Victoria has also been slowed by the rise of COVID-19, which has stopped much field work. But when work resumes, Barekye says a communications and market strategy will also be developed to find the best pathways for placing the 3R Victoria in the hands of farmers, and their healthy potatoes into the markets.