小麦苗期慢叶锈抗性配合力和基因效应的初步研究

A PRELIMINARY STUDY ON THE GENE EFFECTS AND THE COMBINING ABILITY OF SEEDLING SLOW-RUSTING RESISTANCE IN COMMON WHEAT

本文用6个亲本组配成双列杂交设计,分析了普通小麦苗期慢叶锈性的配合力及基因效应。结果表明,F_1代不同组合间苗期叶锈潜育期存在明显差别,多数组合表现正向杂种优势。该性状属于数量性状遗传,由加性效应和非加性效应共同控制。一般配合力和特殊配合力方差均达到极显著水准。不同亲本之间一般配合力效应差异显著。“80—57”的一般配合力效应为第一位,含有的有利显性基因也最多。选择配合力好的亲本进行组配是选育抗叶锈品种的积极有效的途径。

The gene effect and the combining ability of seedling slowrusting resistance in common wheat were analysed in this experiment on a 6×6 diallel cross. The results indicated the significant difference in seedling leaf rust latent period among cross combinations of F1 generation and positive heterosis in the majority of combinations.Being a quantitative character, the seedling leaf rust latent period was genetically controlled by both additive and nonadditive gene effects. The analysis of combining ability variance revealed that both GCA and SCA variances were strikingly different. '80-57' was the most prominent parent which had most favourable dominant genes and ranked first in terms of GCA effect among the materials examined. It was one of the most effective methods to select parents according to combining ability for breeding wheat cultivars resistant to leaf rust.