Breeders seek a breakthrough to help farmers facing an uncertain future.

It is a worrying sign for Ellis, the now-retired director of the gene bank at the International Potato Center (CIP) in Lima. People have grown potatoes in this rugged stretch of the Andes for thousands of years. In recent years, that task has gotten tougher, in part because of climate change. Drought and frost are striking more often. The rains come later, shortening the growing season. And warmer temperatures have allowed moths and weevils to encroach from lower elevations.

To find potatoes that can cope with those challenges, researchers and Peruvian farmers are testing dozens of the 4350 locally cultivated varieties, or landraces, kept in CIP’s refrigerated storage. The plants in this plot fell short. “Native landraces evolved over time,” Ellis says. But, he says, climate change is happening “too fast for these varieties to adapt.”

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