[Detection and analysis of QTL for resistance to the brown planthopper, Nilaparvata lugens (Stål), in rice (Oryza sativa L.), using backcross inbred lines]

Abstract

A mapping population of 98 BC1F9 lines (backcross inbred lines: BILs), derived from a backcross of Nipponbare (japonica)/Kasalath (indica)//Nipponbare by the single-seed descent methods, was used to detect quantitative trait loci (QTL) for resistance to brown planthopper (BPH), Nilaparvata lugens (Stål). Seedbox Screening Technique (SST) was applied to evaluate the reactions of two parents and 98 BILs to BPH at the seedling stage, and the entries were graded on ratio of dead seedlings. A total of three QTL controlling BPH resistance were detected on chromosomes 2, 10 and 12, respectively. Individual QTL accounted for between 10.4% and 16.6% of the phenotypic variance, and the resistance of all the three QTL came from Kasalath, the moderate resistance parent. These QTL should be useful in breeding of varieties resistant to BPH in marker-assisted selection (MAS) program.