Comparison of genetic linkage map and QTLs controlling flag leaf traits based on F2 and F2:6 populations derived from japonica rice.

A comparative analysis was performed on genetic information and QTLs controlling flag leaf traits including length,width and specific leaf weight of flag leaf between two populations (F2 and F2:6) derived from a cross between two japonica rice cultivars,Shennong 265 and Lijiangxintuanheigu(LTH).On the two genetic linkage maps most markers had the same order along chromosomes,but the genetic distance between two markers was different.Thirty and thirteen markers showed genetic distortion significantly and extremely significantly in F2 population,separately.Nineteen and eleven markers deviated toward Shennong 265 and LTH,separately.Sixty-two and thirty-eight markers showed genetic distortion significantly and extremely significantly in F2:6 population,separately.Forty-three and nineteen markers deviated toward Shennong 265 and LTH,separately.These distortional markers formed ten segregation distortion regions (SDRs).Six of them were detected in both F2 and F2:6 populations.F2:6 population had more powerful detective ability than F2 population in QTL dectection.Seven QTLs controlling flag leaf traits including two controlling leaf length,four controlling leaf width and one controlling specific weight were detected in F2 population.Whereas seventeen QTLs for these traits (seven for leaf length,five for leaf width and five for specific leaf weight) were detected in F2:6 population.Four QTLs were detected in both populations including qFLL9 controlling flag leaf length on chromosome 9,qFLW4 controlling flag leaf width on chromosome 4,qFLW12.1 controlling flag leaf width on chromosome 12 and qSLW6 controlling specific leaf weight on chromosome 6.Among them,qSLW6 (Additive effect was 1.956 mg/cm2) for specific leaf weight has a high research and application value.