Black shank, caused by the soilborne pathogen Phytophthora parasitica var. nicotianae , is an important root and crown rot disease of flue-cured and Burley tobacco in North Carolina. The most common race of the pathogen in both tobacco types is race 0. Race 1 of the pathogen has been a minor, but important, part of the pathogen population in the Burley area for many years. In the last several years, race 1 has become more widespread in the Burley area, and now occurs in about 50% of the fields that have black shank present. Race 1 also has increased in importance in the flue-cured region due to the release of varieties with race 0 immunity. This study was initiated to determine the effects of resistance genes present in commercial tobacco varieties on the population dynamics and race structure of the pathogen. Rotation studies were established with varieties containing the Florida 301 source of resistance and varieties containing the PH gene. Results from three years of rotation and greenhouse methodologies for determining pathogen race will be discussed with emphasis on management of black shank.