Sources of resistance to bacterial wilt in Capsicum

摘要

Seventy-four sweet pepper accessions (Capsicum annuum), 59 hot pepper accessions (C. annuum), and 63 other Capsicum spp. accessions were screened for resistance to bacterial wilt (Ralstonia solanacearum). After the plants were transplanted to a field infested with R. solanacearum, an inoculum suspension of R. solanacearum was poured around them. For evaluation of resistance, each accession was scored by using a disease index ranging from 0 = symptomless to 4 = death. Highly resistant accessions whose disease index was less than 1 were evaluated again by a seedling test. Highly resistant accessions were found most particularly in sweet pepper and their commercial F1 cultivars. Mie-Midori and its progenies were used as parents for the breeding of nearly all resistant Japanese green pepper cultivars identified in this study. In sweet and hot peppers which originated in Asia, i.e., Japan, China, etc., high or moderate resistance to bacterial wilt was shown, whereas those from other areas such as North and South America, Europe, etc., had varying degrees of susceptibility.