MAPPING OF QTLS FOR YIELD AND ITS COMPONENTS IN A RICE RECOMBINANT INBRED LINE POPULATION

Abstract

Quantitative trait loci (QTLs) for rice (Oryza sativa L.) yield and related components have been reported in recent years. However, due to differences between the genetic backgrounds, type of molecular markers and the tested environment the results describing the number of QTLs, chromosomal regions and nature of the additive effects could be different. The purpose of this study was to map QTLs conferring the yield and yield related components in a rice recombinant inbred line (RIL) population. A linkage map consisting of 119 simple sequence repeat (SSR) markers was constructed based on an RIL population with 307 lines derived from a cross between Guanghui 116 (male) and LaGrue (female). Mapping of the QTLs for grain yield per plant, number of grains per panicle, 1000-grain weight, seed-setting rate and number of tillers per hill, was carried out based on the composite interval–mapping method. The additive effects and the percentage of phenotypic variation for all the traits involved were also estimated. Fifteen QTLs were detected on chromosomes 1-6, 8, 9 and 12. Among these, nine QTLs were reported earlier, indicating their stability across genetic backgrounds. The markers, qTL-3, qTL-6, qTL-12, qSS-5, qSS-9 and qGY-8, which control the tiller number, seed-setting rate and grain yield per plant, have not been detected in previous studies.