การพัฒนาเครื่องหมายโมเลกุลชนิด SNP ซึ่งจำเพาะต่อความต้านทานเพลี้ยไฟ (Thrip palmi) ในพริก

Abstract

Thrips (Thrips palmi; T. palmi) are among the most pepper damaging pests in Thailand. The objectives of this work were to study a level of resistance and identify DNA markers that related to T. palmi resistance in pepper. Seventeen pepper accessions were classified for T. palmi resistance using two resistant test methods which are free choice and no choice. Resistance test revealed that Capsicum annuum (C. annuum) AC 1979 and C. annuum Berceo were most resistant and susceptible accessions, respectively. These 2 accessions were used as parental line to produce 195 plants F2 population for a linkage mapping construction from 161 polymorphic SNP markers. The linkage map and Disease Index and the Area Under the Disease Progress Curve data from free choice method were analyzed for Quantitative Trait Loci (QTLs) . The highly significant QTL1and QTL2 were found, located on chromosome 3 and 12, with about 12.9 and 8% explained phenotypic variance, respectively. Therefore, these QTLs were associated with T. palmi resistance. Moreover, M238 and M171 SNP markers were identified in these QTLs which will be used in pepper marker-assisted breeding for T. palmi resistance.