Commercial planting media effective in screening for Verticillium wilt of Capsicum annuum

Abstract

Three commercial planting media (Sunshine Mix 1, Sunshine Mix 5, and Metro Mix 360) were compared with the standard soil mixture prepared at New Mexico State Univ. for their effectiveness in differentiating Verticillium wilt-resistant and susceptible accessions of chile (Capsicum annuum L.) Each medium was infested with Verticillium dahliae Kleb. microsclerotia and planted with the resistant and susceptible accessions. When susceptible populations exhibited severe symptoms, individual plants were rated for disease severity (1 = no symptoms to 9 = death). Mean disease severities of populations differed among planting media, and, regardless of medium, resistant and susceptible populations were readily differentiated. Mean disease severities of plants grown in Sunshine Mix 1 and Sunshine Mix 5 differed from those grown in the standard University soil mix, but all media provided reliable screening tests. Mean disease severities of plants grown in Metro Mix 360 were most similar to those of plants grown in the University mix. Furthermore, greater differentiation was apparent between resistant and susceptible accessions in Metro Mix 360 than in accessions grown in the University medium.