Pepper Accession LS2341 Is Highly Resistant to Ralstonia solanacearum Strains from Japan

Bacterial wilt caused by Ralstonia solanacearum is one of the most serious diseases in pepper (Capsicum annuum) crops in warm-temperate, subtropical, and tropical areas, including Japan. Resistant lines are a prerequisite for breeding resistant cultivars but are not well studied. Eight pepper accessions previously described as resistant to the pathogen were selected and inoculated with a highly virulent strain, KP9547. Among them, Malaysian accession LS2341 exhibited the highest resistance. Accession LS2341 was then challenged with 14 virulent strains collected from various areas in Japan. The strains cover biovars 2T, 3, and 4 and include isolates from the host plants of tomato, eggplant, and pepper. Results indicated that accession LS2341 had the highest level of resistance to all the strains of R. solanacearum examined. Therefore, accession LS2341 was confirmed as an appropriate source for the breeding of resistant cultivars of pepper in Japan and is a candidate for a potential source of resistance in other areas.