Rwanda’s potato farmers have welcomed the ongoing trials with a new variety of Irish potato that is more resistant to late blight disease, a devastating disease that impacts tomatoes as well. Late blight infects potato tubers and tomato fruits, as well as leaves and stems.
The disease is caused by the fungus phytophthora infestans, and occurs later in the growing season as symptoms are not known until after the crop has blossomed. It typically appears in older, lower-hanging leaves, and causes grey-green spots that appear to be wet. These spots then darken and a white fungal residue can be found on the other side. The entire plant can then be infected and damaged, sometimes killing a good portion of a harvest if not caught in time.
The International Potato Centre in East Africa (Centro Internacional de la Papa, or CIP) has said that late blight disease can kill between 60% and 100% of the crop. In Rwanda, the Centre’s scientists have been working on ways to transfer resistance genes from wild potato varieties to already-farmed varieties within the country to fight the disease. The new potato variety is being created by making use of biotechnological tools, including gene editing.
If all goes according to plan, the new variety of late blight disease-resistant Irish potatoes will be ready for distribution by 2025.
Potato production over the years
“Potato was probably introduced to Uganda by British colonial administrators early in the twentieth century as a backyard garden vegetable. Another probable source of potato introductions came from Kenyan, Rwandan, and Congolese farmers and traders located along the borders, whence the crop diffused among Ugandan farmers living in the cool highlands of the country. By 1945, the potato was widely grown in the highlands of Kigeri and Bugizu and was even described as a weed as well as a crop. Production was severely damaged in the late 1940s by infestations of late blight (phytophthora infestans) and to a lesser extent early blight (Alternaria solani),” the CIP official website reads.
According to Athanase Nduwumuremyi, one of the Rwanda Agriculture and Animal Development Board (RAB) members, the new potato variety will also decrease farmers’ dependence on agrochemicals such as pesticides.
A total of 3.9% of the total cultivated land in Uganda is developed for potato farming. The third most widely grown food crop in Rwanda is Irish potatoes. However, while having a potential output of more than 30 tonnes, the average potato productivity is just 10 tonnes per acre.
Benefits of new variety
Nduwumuremyi believes that the new potato variety is also being engineered to grow more easily, upping productivity on the farms dedicated to growing the root vegetable. In 2021, Rwanda expects its potato yield per acre to be 13.5 tonnes; in 2024, it expects it to be 14 tonnes. The strategic plan for the agricultural sector projects that production, grown on 106 236 hectares across the nation, will rise from 1 194 677 tonnes in 2021 to 1 487 304 tonnes in 2024.
The potato will also adhere to biosafety law guidelines. The Rwanda Environmental Management Authority (REM) drafted a law governing GMOs in the country in 2018, and it was forwarded to the Rwanda Law Reform Commission for review. The goal of the law is to guarantee a sufficient level of protection in the area of the safe transfer, handling, and use of GMOs produced by contemporary biotechnology that may hurt the preservation and sustainable use of biological variety.
To implement the Cartagena Protocol, to which Rwanda is a signatory party, and to establish a clear and predictable procedure for review and decision-making on such genetically modified organisms and related activities, the draft law also takes into account hazards to human health.
“The biosafety law has all guidelines although it is not yet passed. The draft law is in the prime minister’s office after coming from the law reform commission. What we are doing now is to get approval based on the law governing research in general,” said Nduwumuremyi. “Before the new variety is released to farmers, a biosafety law will be in place. Otherwise there will be ministerial orders or guidelines and the Food and Drugs Authority will check if the variety meets standards as food and seed.”