QTL Mapping and Epistasis Analysis of Yield Associated Traits in an DH Population from Indica-Japonica Cross of Rice (Oryza sativa L. )

A double haploid (DH) population derived from a cross between a japonica female parent Balilla and an in-dica male parent N11 was used to construct a molecular linkage map with software Joinmap 3. 0. A total of 136 markers consisting of 10 STSs, 11 CAPs and 104 SSRs were used to identify additive effect (A) of quantitative trait loci (QTL) and their additive×additive epistasis (AA) for the yield associated traits. 6 agronomic traits of 132 DH lines, with software QTL mapper 1.0 based on mixed linear models, 50 QTL were detected, including 7 QTL only have additive effects, 3 QTL have additive effect and additive ×additive epistasis, and 40 QTL only have additive ×additive epistasis. Among the additive effects and the epistasis effects, the variation explained by QTL rangs from 3. 87% to 24. 62%. The result showed that the main effect QTL are easy to be detected from different populations and different environments, the QTL of associated traits often located on the same loci or near region of a chromosome.