The stem nematode, Ditylenchus dipsaci, is a threat to some 4,000 hectares of sugar beet in Switzerland alone. Infection by this nematode leads to necrosis and rot, which can mean up to 50% yield loss. There are currently no effective chemical control measures against this pest. Tolerant cultivars in combination with late sowing is a less than satisfactory alternative, and it does not offer any sustainable prospects for the affected production areas. Besides preventive measures such as long rotations, the use of resistant cultivars is the only option for sustainable control of D. dipsaci in infested fields. In the scope of a PhD project and in cooperation with KWS Saat SE, Schweizerische Fachstelle für Zuckerrübenbau (Swiss expert centre for sugar beet production), Julius Kühn-Institut and the University of Göttingen, we are studying resistance against D. dipsaci in sugar beets.