Powdery mildew caused by Oidiopsis taurica is one of the major diseases of Capsicum spp., causing damage due to defoliation of up to 75% and yield losses of up to 40%. Disease control with fungicide is inefficient, genetic resistance being the best way of control. Few resistant sources have been identified in Capsicum annuum. Capsicum spp. collection accesses of USP/ESALQ germplasm bank were screened in their reaction and identification of new resistance sources. The screening was carried out in a greenhouse under high inoculum pressure. Disease was assessed during fruit production using a severity scale varying from 1 (resistant) to 5 (highly susceptible). From 156 accesses evaluated 53 were resistant, represented by five accesses in C. annuum, 31 in C. baccatum and 17 in C. chinense. The hv-12 was the most resistant among the C. annuum accesses. Two new resistant sources were found in C. annuum, # 124 and chilli. These accesses showed different resistance mechanisms through hypersensitive host reaction. The commercial hybrids Reinger, Nathalie, Margarita, Magali R and Magda were susceptible or highly susceptible. Most of C. baccatum and C. chinense resistant accesses showed defoliation as a consequence of hypersensitive mechanism.
Capsicum spp.; Leveillula taurica (Lev.) Arn.; genetic resistance