Analysis of Combining Ability and Heritability of Yield Traits from Rice Long Panicle and Big Grain Germplasm Resources

5 indica restorer lines and 6 germplasm resources of long panicle and big grain were chosen for the analysis of combining ability and heritability of 7 yield traits by incomplete diallele cross(NCII)design.The results showed that 7yield traits were influenced by the additive effect and non-additive effect of parent at the same time,major factor was additive effect.Except plant height,seed setting rate,panicles per plant,grain weight per plant,the characteristics were greatly affected by germplasm resources of long panicle and big grain.The panicles per plant and grain weight per plant were not only influenced by the specific combining ability of parent but also by the general combining ability of the restorer lines.Narrow sense heritability of plant height and 1 000-grain weight were higher,might be selected in early generation,narrow sense heritability of main panicle length,spikelets per panicle,seed setting rate,panicles per plant,grain weight per plant were lower,early generation selection is not good.General combining ability of many characteristics of CD-1 was the best;CD-4and CD-5 may be used as agronomic parent of big grain breeding.R527×CD-3 may be used as excellent combination of selecting parent of big or heavy panicle type;Duoxiyihao×CD-4 may be used as combination of selecting parent of more panicle type;R527×CD-1 may be used as combination of selecting parent of big grain type.