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<div>Soybean cyst nematode (SCN, <i>Heterodera glycines</i>)<i> </i>is the most economically important soybean pathogen in the United States. Host resistance effectively controls SCN, however populations virulent to PI 88788 resistance are evolving, warranting additional controls options. The objectives of this study were: 1) to determine the effects of nematode seed treatments on SCN reproduction on different SCN resistance sources, and 2) to determine if seed treatments combined with host resistance could slow development of virulence to host resistance sources. Four seed treatments (clothianidin + <i>Bacillus firmus</i>, fluopyram, clothianidin + <i>B. firmus</i> with fluopyram, and a nontreated control) were compared on two resistant sources, PI 88788 and Peking. Treatments received a base seed treatment of penflufen, prothioconazole, and metalaxyl. Using a population virulent to PI 88788, eggs were serially passed for 3 generations on the same treatment and then a modified SCN-type tests was performed on each SCN population. Fluopyram significantly decreased SCN reproduction but there was not a significant difference between resistant sources (p=0.05). Fluopyram treatments significantly slowed development of virulence to PI 88788 (p=0.10), but this was not observed with virulence to Peking. These results suggest that seed treatments containing fluopyram could have additional benefits in the management of SCN resistance when paired with resistant varieties. <p> </div>