水稻KV型细胞质雄性不育系的选育及其胞质效应研究初报

水稻ＫＶ型不育系与ＷＡ型不育系在育性表现和恢保关系上基本相同，但可恢性更好，恢复谱更广。特别是ＫＶ细胞质对杂种的每穗粒数及结实率有显著的正效应．因而它是个利用前景更广泛的新质源不育系．

Breeding of A New CMS Lin with KV Cytoplasm in Rice and Studies on Its Cytoplasmic Effects.

Khao Vay, a glabrous rice variety of Thaliand originated from a cross of indica/japonica,was used as the female pemale and crossed to IR30,a nonglabrous indica rice restorer, and it was found that in the F2 and F3 generations, many male sterile plants appeared Four highly sterile plants in the population of an F3 generation were chosen to be beted and backcrossed with the maintainer V41B,reslting in the development of a new V41A with the cytoplasm of khao Vay (KV type V41A) The newly-bred KV type V41A pos- sesses identical nucleus to but different cytoplasm from another V41A developed in 1970s with wild abortive (WA) cytoplasm (WA type V41A). For many years' observation, it has been found that compared with WA type V41A,KV type V41A is aimilar in high and stable sterility, but better in restorability. Crossed with 12 restorers of 4 proups, i.e. the groups of indica,inclined to japonica and javanica, these two CMS lines, were compared in their cytoplasmic effects on the heterosis of F1 hybrids. The results showed that the KV type cytoplasm was significantly superior to WA type cytoplasm for its higher heterobeltiosis values of 5 characters including effective panicles,spikelets per panicle, seed set,1000-grain weight and grain yield per plant in the F1 hybrids.