Abstract:The 289 DH lines derived from the cross BS20×Fu3 were used for mapping QTLs of photoperiod-temperature sensitive genic male sterility in this study. Field trials were conducted in Beijing and Fuyang, Anhui Province, during 2005~2006 cropping season. The fertility investigated included seed setting rate and seed setting spikelet rate. The fertility-related QTLs were mapped using SSR markers and bulked segregant analysis (BSA). The genetic map consisted of 128 SSR markers. Three SSR loci Xgwm294, Xgwm374 and Xgwm44 on chromosomes 2AL, 2BS and 7DS, respectively, showed linkage with the fertility genes in the BSA analysis of sterile DNA pool and fertile DNA pool. Using mixed-model composite interval mapping, 6 QTLs were detected on chromosomes 1AS, 2BS, 2DL, 6AL, 6BL and 7DS, accounting for 1.1~12.5% of the phenotypic variance across two environments. Significant interactions were found between the QTL on 7DS and those on 2BS, 6AL and 6BL. Finally, two important QTLs were detected on chromosomes 7DS and 2BS in the marker intervals of Xgwm44-Xcfd14 and Xgwm148-Xgwm374, explaining 7.2~12.5% and 2.1~2.5% of phenotypic variances, respectively.