Over the past ten years, approximately 1,000 Swiss farms have given up potato cultivation due to increasing disease and pest pressure, tighter restrictions on plant protection products, and extreme weather events such as heatwaves and prolonged wet conditions. In response, Agroscope has launched a new field trial at the Protected Site in Zurich-Reckenholz as part of the National Research Programme (NFP) 84. The trial features the potato line P49 27, developed at Wageningen University, which is resistant to late blight—the world’s most significant potato disease. The study, approved by the Federal Office for the Environment (BAFU), focuses on “cisgenic” potato varieties that contain no foreign genes, require fewer pesticides, and are better able to withstand weather extremes.
The experimental line carries the resistance gene Rpi-chc1 from the wild potato Solanum chacoense, enabling natural defence against the blight fungus. As only a potato-specific gene was introduced, the line is considered cisgenic. This field trial is embedded in the international CRISPS project, which also explores genome-edited potato varieties. Agroscope is collaborating with research partners in the Netherlands and Sweden to improve two Swiss varieties, Innovator and Erika, as well as the old standard variety Désirée. Over the coming years, they aim to repair available resistance genes or selectively knock out susceptibility genes, then test the plants in the field. While conventional breeding methods are reaching their limits—often taking over 20 years to produce results—new techniques like the CRISPR-Cas gene scissors offer a promising alternative, allowing precise breeding of natural traits within just a few years without using foreign DNA.
