6个两系籼稻不育系配合力测定及产量关联研究OA

To screen strong heterotic hybrid combinations and elite parents of two-line indica rice suitable for production and establish an efficient breeding and screening system,this study used 6 male sterile lines(S1-S6)of two-line indica rice and 10 restorer lines(R1-R10)as materials to prepare 60 hybrid combinations by NC Design Ⅱ.Eight core agronomic and yield traits including plant height and panicle length were systematically determined.Quantitative genetic methods were used to analyze combining ability effect and genetic variation characteristics.A quantitative correlation model between theoretical yield(Yt)and actual yield(Y)was constructed.The results indicated that there were significant genetic differences in the traits among the tested materials,with the coefficients of variation for total grains per panicle,filled grains per panicle,and yield per plant being 18.58％,18.69％,and 15.98％,respectively,highlighting the potential for genetic improvement.General combining ability(GCA)analysis showed that the sterile lines S2 and S3 and the restorer lines R4 and R10 exhibited significantly positive effect on key yield traits,being core parents with excellent comprehensive traits.Specific combining ability(SCA)analysis identified strong heterotic combinations such as S1/R4(actual yield per plant SCA=5.78),S6/R10(actual yield per plant SCA=5.80),S5/R1(actual yield per plant SCA=5.44),S2/R4(actual yield per plant SCA=3.40),and S3/R4(total grains per panicle SCA=32.72),revealing significant genetic complementarity effect between parents.Actual yield(Y)was positively correlated with theoretical yield(Yt)(r=0.93**),and the regression model Y=0.63Yt+13.59(R2=0.868)effectively explained the variation of actual yield.This study unveiled the key indicators for parent selection and the screening criteria for heterotic combinations of two-line indica rice,providing reference for breeding hybrid rice with high yields.