Abstract

Phytophthora blight (caused by Phytophthora capsici) is an important disease with a broad host range including Solanaceous, Cucurbitaceous, and Fabaceous crops. In pepper, P. capsici causes crown, root, and fruit rot as well as foliar lesions. Disease management relies primarily on the application of fungicides, planting of tolerant cultivars, and cultural practices. Field trials were conducted over the summers of 2015 and 2016 to evaluate 32 commercial hot and bell pepper cultivars in North Carolina (NC). The cultivars Martha-R and Meeting were found to be the most resistant to a group of isolates from NC. Ebano-R, Revolution, Paladin, and Vanguard showed intermediate levels of resistance. Bastille, Red Knight, and Plato were highly susceptive to P. capsici. Greenhouse experiments were conducted to determine the virulence of three individual P. capsici isolates across 48 commercial hot and bell pepper cultivars. The isolates exhibited different levels of virulence to the pepper cultivars screened for crown and root rot resistance. Cultivars CM334, Martha-R, Meeting, and Intruder were resistant to the isolates tested. In addition, we phenotypically characterized a P. capsici isolate collection from NC for fungicide sensitivity and mating type. This information will be useful for NC growers in selecting resistant cultivars and for future population genetics analyses.