Isaac Nzabarinda, a 66-year-old potato farmer and seed multiplier from Kinigi Sector, has spent the last 25 years combating late blight disease with routine fungicide spraying, especially during rainy seasons when the disease spreads rapidly.

Nzabarinda is among hundreds of potato farmers and seed multipliers in Musanze District who spend significant amounts of money on fungicides to protect their crops. On one-hectare alone, he spends about Rwf500,000 each season on fungicides and sprays up to eight times, in addition to paying casual workers to apply the chemicals.

According to Nzabarinda, farmers who fail to spray adequately during rainy seasons can incur losses of up to Rwf700,000 per hectare.

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Rwandan farmers currently grow 11 potato varieties, but two new fungicide-free varieties are expected to be released to seed multipliers in September following the successful completion of trials, according to the Rwanda Agriculture and Animal Resources Development Board (RAB).

The new varieties called Ndamira and Victoria have been bred to resist late blight disease, offering renewed hope to potato farmers in Musanze and other potato-producing districts.

"We really need these improved potato varieties,” said Nzabarinda. "It is a breakthrough for us. Being able to plant and harvest potatoes without spraying fungicides would eliminate a major production cost and bring many benefits.”

Nathalie Mujawimana, an agronomist based in Gicumbi District, said the benefits extend beyond reducing production costs.

"It is a milestone in agricultural research and a game changer for potato farming,” Mujawimana said. "Reducing fungicide use benefits human health and helps protect the environment, since some pesticides can be harmful to people and animals.”

The new potato varieties were developed through conventional breeding using wild potato relatives. The breeding programme aimed to increase yields while addressing the devastating effects of late blight disease, which can cause losses of from 80 to 100 percent of harvests when fields are left unsprayed.

Trial results for showed that even without fungicide spraying the Ndamira variety can yield up to 30 tonnes per hectare, while Victoria achieves a similar yield of 33 tonnes per hectare—demonstrating their potential to improve productivity while reducing production costs.

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Anastase Nduwayezu, a potato pathology scientist at RAB, confirmed to The New Times that the new varieties have reached Phase Four—the final stage of development, meaning that they are ready to be distributed for large scale farming and human consumption.

"We have tested the new potatoes, their colour and taste remain unchanged,” Nduwayezu said. He added that the field trials conducted in Musanze, Nyamagabe, Rubavu, and Burera districts have produced promising results.

Scientists report that the varieties showed strong resistance to late blight and were not affected by potato viruses during the testing period.

"The new varieties showed no symptoms of late blight,” he added.

RAB plans to distribute the new seeds to a limited number of seed multipliers between September and October 2026 before gradually expanding production within two years.

"We will initially provide the new seeds to a small number of farmers, but we expect to significantly increase availability by the end of 2027,” he noted.