摘要： 以显性雄性不育小麦为材料,采用改良半姊妹和混合轮回选择两种方案,对同一基础群体C₀进行了四轮选择.结果表明,对主穗粒数、单株粒重和百粒重等主要产量性状,两种方案均有较显著的改良效果.遗传进展比较,改良半姊妹方案所取得的进展较大,但两方案间差异未达到显著水准.对降低群体植株高度,用改良半姊妹方案的效果极显著,而混合轮选较差.同一方案逐轮间各性状的增进值较小,呈波浪式进展趋势.群体变异程度比较表明,两种方案逐轮群体的变异系数皆呈下降趋势,改良半姊妹方案的下降幅度略大于混合轮选.

关键词: 改良半姊妹轮回选择, 混合轮回选择, 群体改良, 基础群体, 遗传进展, 显性雄性不育小麦

Abstract: The same basic population C0 had been selected for four cycles with Dominant male sterile wheat by means of the half-sib mating recurrent selection and the mass recurrent selection programmes.Results indicated that notable effects had been obtained in the main yield characters, such as kernel number of the main spike, kernel weight per plant and 100-kernel weight with the two selection programmes. A comparison in genetic advance showed that the advance gained by the improved half-sib mating recurrent selection was greater than that of the mass selection, but there was no significant difference between them. As to the effect of decreasing plant height, the effect of the improved half-sib mating selection was very significant, while that of the mass recurrent selection was not so significant. The increasing value of each character between cycles in the same selection programme was rather small and showed a tendency of wave advance. The variation degree of the population showed that the coefficient of variability tended to decrease for the two selection programmes, but the decreasing degree of the improved half-sib mating selection wa.s a little bit higher than that of the mass selection.

Key words: Improved half-sib mating recurrent selection, Mass recurrent selection, population improvement, Basic population, Genetic advance, Dominant male sterile wheat