粳稻穗部性状遗传分析

Genetic Analysis of Panicle Traits in Oryza sativa ssp. japonica

从粳稻(Oryzasativassp.japonica)RIL群体中选取每穗颖花数极端少的品系丙堡3201和丙堡3205及每穗颖花数极端多的品系丙堡3145和丙堡3214,配制丙堡3201×丙堡3145和丙堡3214×丙堡3205两个组合的P1、P2、F1、B1、B2和F26个世代,调查每穗颖花数、每穗实粒数、穗长、一次枝梗数和二次枝梗数的表型分布,并运用主基因+多基因混合遗传模型,对这5个性状进行了遗传分析。结果表明,每穗颖花数性状在2个组合的各分离世代均未出现超亲分离,而其它4个性状均有不同程度的超亲分离。一次枝梗数受1对主基因+多基因控制;其余4个性状均受2对主基因+多基因控制。每穗颖花数、每穗实粒数、穗长和二次枝梗数4个性状以主基因遗传为主,一次枝梗数性状以多基因遗传为主。

We investigated phenotypic distributions of spikelet number per panicle （SNP）, filled grain number per panicle （FGP）, panicle length （PL）, primary branch number per panicle （PBNP） and secondary branch number per panicle （SBNP） in P1, P2, F1, B1, B2 and F2 generations of 2 crosses of Bingbao 3201×Bingbao 3145 and Bingbao 3214× Bingbao 3205 of Oryza sativa spp. japonica. We also conducted genetic analysis of the 5 traits by using the mixed major gene plus polygene inheritance models. Bingbao 3201 and Bingbao 3205 had extremely small panicles, whereas Bingbao 3145 and Bingbao 3214 had extremely large panicles. All 4 lines were selected from a recombinant inbred line population bred previously in japonica rice. Three segregation generations of both crosses revealed transgressive segregation of FGP, PL, PBNP and SBNP but not SNP. Genetic analyses showed that PBNP was controlled by 1 major gene plus polygenes. Traits of SNP, FGP, PL and SBNP were controlled by 2 major genes plus polygenes. Traits of SNP, FGP, PL and SBNP were mainly governed by major genes, while PBNP was mainly governed by polygenes.