Technical Abstract: The soybean cyst nematode (SCN; Heterodera glycines Ichinohe) is a new pathogen to the Red River Valley (RRV) region of Minnesota and North Dakota. SCN populations in the RRV have started to build to high levels in cropping rotations that include soybean, the main host for SCN. SCN is very closely related to the sugarbeet cyst nematode (SBCN; Heterodera schachtii Schmidt), a devastating pathogen of sugarbeet not known to exist in the RRV. Although sugarbeet is not considered a host of SCN, the nematode may attempt to penetrate sugarbeet roots to establish a feeding association. The penetration and disruption of the tissue by SCN could provide points of entry for sugarbeet pathogens or alter the physiology of the root to increase susceptibility to pathogens. The close relatedness of SCN and SBCN, in conjunction with the recent increases in soybean production in the RRV that are increasing SCN inoculum levels, is a potential concern for sugarbeet production if SCN increases severity and/or occurrence of other sugarbeet diseases. This research project will investigate the influence of SCN on seedling diseases of sugarbeet.