SNP analysis for anthracnose resistance in Capsicum spp.
Anthracnose, caused by Colletotrichum spp., is a serious problem for chili production in Asia, and other tropical and subtropical regions worldwide. Two key resistance genotypes including Capsicum chinense 'PBC932' and C. baccatum 'PBC80' have been shared among chili breeders in Asia. SNPs (single nucleotide polymorphisms) were mapped to identify quantitative trait loci (QTLs) that were responsible for the anthracnose resistance in two chili populations derived from 'PBC93' and 'PBC80'. Of 1036 SNPs developed from C. annuum, 288 were mapped in the F2 population of C. annuum 'Bangchang' × C. chinense 'PBC932' using Joinmap 3.0 (LOD 6.0-10.0). The map contained 12 linkage groups spanning 824 cM. Two minor QTLs were identified on the same location of LG2 between two SNP loci, which were 14 cM apart, using MapQTL 4.0 and the interval mapping approach. Each QTL accounted for almost 20% of the resistance variance on the mature green and ripe fruit. Out of 1165 SNPs developed from C. baccatum, 403 were mapped with the F2 population of C. baccatum 'PBC80' × 'CA1316'. The map contained 12 LGs covering 1270 cM. Three major QTLs were identified on the same location of LG10 between two SNP loci, which were 17 cM apart. Each of the three QTLs accounted for more than 85% of each trait variance, which were the resistance assessed by microinjection with Colletotrichum pathotypes PCa2 or PCa3 and the resistance assessed by high-pressure spray with PCa3.
Mongkolporn, O., Mahasuk, P. and Struss, D. (2016). SNP analysis for anthracnose resistance in Capsicum spp.. Acta Hortic. 1127, 109-116
Capsicum baccatum, Capsicum chinense, chili, Colletotrichum, QTL, map