Abstract: Genetical analysis of dwarfism in two double-dwarf germplasms indicated that the dwarfism in Qiannong and Te’ai were controlled by two recessive dwarf genes, respectively, of which a common one was allelelic to sd-1 and the others were non-allelic to sd-1. Xinqian’ai and Xinte’ai possessing new semi-dwarf genes sd-q(t) and sd-e(t)from Qiannong and Te’ai, respectively, were selected.Allelism test between sd-q(t)and other genes conferring dwarfism or semi-dwarfism in rice indicated that sd-q(t) was non-allelic to d-29, d-32, d-59, sd-g, sd-6 and d-1^X . Xinqian’ai carrying the new semi-dwarf gene sd-q(t) showed to have promising characteristics on agro nomic traits such as grain number per panicle, 1000-grain weight and seed setting rate, suggesting that sd-q(t) might be utilized in rice breeding in rep lacement of sd-1 gene.

Key words: rice, dwarfism, genetical analysis, allelism

摘要： 对黔农和特矮两个双矮地方种质株高性状的遗传分析结果表明，黔农和特矮的矮生性均由2对隐性矮生基因控制，其中各有1对矮生基因与sd-1等位，另1对与sd-1不等位。黔农中两对矮生基因降低株高的效应不同，与sd-1不等位的矮生基因控制的株高比sd-1略矮；而特矮的两对矮生基因具有相同的降低株高效应。将分别来自黔农和特矮的携带新半矮生基因的材料命名为“新黔矮”和“新特矮”，各携带新的半矮生基因sd-q(t)和sd-e(t)；其中新黔矮携带sd-q(t)与sd-g(t)等6个矮秆半矮秆基因均不等位。新黔矮在每穗粒数、结实率和千粒重等农艺性状上表现较好，有希望应用在育种和生产上替代sd-1。

关键词: 水稻, 矮生性, 遗传分析