Diallel crosses test of six isonuclear alloplasmic CMS lines in rice.

Forty-two hybrid combinations were obtained from six isonuclear alloplasmic CMS lines × seven different restorer lines by using the incomplete diallel crosses design. The results from analyzing their heritability and combining ability of nine main characters showed that six sterile lines had the significant effect on general combinning ability of effective spike,1000-grain weight,spikelet number per spike,grain density and yield per plant,there was difference in cytoplasm and nucleo-cytoplasmic interaction effects among six alloplasmic isonuclear CMS lines. The non-additive effects were higher than additive effects on characters of yield per plant,spike length and percentage of grain setting in the tested combinations and the additive or non-additive effects were significant on different characters in the same combination or on the same character in different combinations.