Identification of quantitative trait loci associated with anthracnose resistance in chili pepper (Capsicum spp.). [Korean]

摘要

Pepper (Capsicum spp.) anthracnose caused by Colletotrichum acutatum is a destructive disease susceptible to areas where chili peppers are grown. Capsicum baccatum var. pendulum (Cbp) is resistant to anthracnose and has actively been used for interspecific hybridization for the introgression of resistance gene(s) into cultivated chili peppers. The goals of this study were to determine the inheritance of resistance to anthracnose within Capsicum baccatum and to map quantitative trait loci (QTLs) for the anthracnose resistance. A genetic mapping population consisting of 126 F₂ plants derived from a cross between Capsicum baccatum var. pendulum (resistant) and Capsicum baccatum 'Golden-aji' (susceptible) was used for linkage mapping. The linkage map was constructed with 52 SSRs, 175 AFLPs, and 100 SRAPs covering 1,896 cM, with an average interval marker distance of 4.0 cM. Based on this map, the number, location, and effect of QTLs for anthracnose resistance were studied using plants inoculated in the laboratory and field. A total of 19 quantitative trait loci (2 major QTLs and 16 minor QTLs) were detected. Two QTLs (An8.1, An9.1) showed 16.4% phenotypic variations for anthracnose resistance after wounding inoculation. In addition, five minor QTL loci (An7.3, An7.4, An4.1, An3.1, An3.2) showed a total of 60.73% phenotypic variations of anthracnose resistance in the field test. Several significant QTLs were also detected and their reproducibility was confirmed under different inoculation conditions. These QTLs are now being confirmed with different breeding populations. Markers tightly linked to the QTLs that are reliable under different environmental conditions will help to determine the success of marker-assisted selection for anthracnose-resistant breeding programs in chili pepper.