三重测交与小麦群体遗传分析

Triple Test Cross and Genetic Analysis in Wheat Population

本研究对三重测交分析模式做了理论推演,并据此对两套小麦群体材料进行了遗传变异与基因效应—环境互作分析。结果表明:虽然加性—显性模式对大部分性状合适,但上位效应对产量性状的作用不可低估。加性效应在各性状中均为显著或极显著;显性效应在大多数性状中相当重要。而且,加性遗传方差估值多大于显性方差,前者的估值稳定性也明显大于后者。参试性状均表现显著的基因效应—环境互作。加性、显性效应对环境差异的敏感程度相近;但不同类型的上位效应与环境互作的表现不同,其中ad型和dd型与环境的互作更为明显。本研究中aa型上位效应作用较小,ad与dd型居多。试验证明,模式Ⅴ和Ⅶ较为妥善,可在遗传育种研究中广泛应用。

Theoretical derivation is made for mode1s of triple test cross analysis,and genetic variation and the interaction between gene effects and enviro-nments in two sets of wheat population materials are analysed. The resultsshow that although additive-dominance mode is fit for most of the traitsstudied, the effects of epistasis on yield components should not be neglected.The additive effect is significant or highly significant for all characters stu-died; the dominance effect is rather important for the most characters. Theestimates of additive genetic variance are larger than those of dominance,and the stability of the former estimate is also obviously larger than thatof the latter. Significant gene effect-environment interaction is found in all of thecharacters studied. The sensibility degree of additive and dominance effects to the environmental differences are similar; but the interactions betweendifferent types of epistasis and environments are quite different, especiallyfor those of types ad and dd. The effect of epistasis of type aa is not important, and the types of adand dd play the main role. The results testify that model Ⅴ and model Ⅶare quite proper for widely applying in genetie and breeding research.