Genetic Analysis of Clum Thickness Trait in Rice Grown in Different Seasons

Three rice parents with great difference in clum thickness CB1(11.0 mm),CB4(15.5 mm)and CB7(11.5 mm)were chosen to construct the combines CB1×CB4 and CB7×CB4,also the corresponding P1,F1,P2,B1,B2,F2 populations were established and planted in the middle and late planting seasons and the clum thickness traits were checked,respectively.The Akaike's information criterion(AIC) of the major genes plus polygenes mixed inheritance model was used to indentify the existence of major genes affecting quantitative traits in B1,B2,F2 populations,and when the major genes existed,the genetic effects of the major genes and polygenes and their genetic variance were estimated through segregation analysis.One additive major gene plus additive-dominance polygenes was the most fitted genetic model for this trait in the all B1,B2,F2 populations in the two planting seasons.The heritability values of the major genes varied from 27.60 percent to 63.69 percent and those of polygenes varied from 1.39 percent to 30.07 percent,and the total heritability values were from 39.43 percent to 82.01 percent.The heritability of this trait was affected by planting seasons and the combinations.