高丹草叶部性状数量遗传分析

Quantitative Inheritance Analysis of Leaf Traits in Sorghum bicolor×Sorghum sudanenes

本研究选用叶部性状差异大的粒用高粱忻粱52和苏丹草美引-251作为试验材料,构建F2代分离群体,对其单株进行叶片数、旗叶长、旗叶宽、旗叶鞘长、旗叶叶面积5个叶部性状的调查,通过主-多基因分析得出各性状的最适遗传模型及遗传率。结果表明:叶片数符合Model A_4,为负向完全显性混合遗传模型,受1对主基因遗传,主基因遗传率为54.97%;旗叶长符合Model A_1,为1对主基因遗传的加性-显性混合遗传模型,主基因遗传率为46.25%;旗叶宽符合Model A_1,该性状受1对主基因控制,符合加性-显性混合遗传模型,主基因的广义遗传率为51.30%;旗叶鞘长的最适遗传模型为Model A_0,不存在主基因遗传,为微效多基因控制的数量性状遗传;旗叶叶面积符合Model B_1,是由2对主基因遗传的加性-显性-上位性混合遗传模型,控制该性状的主基因遗传率为79.34%;其中,旗叶长的遗传率较低,表明该性状的遗传受环境因素影响较大,不易在后代中稳定遗传,而叶片数、旗叶宽和旗叶叶面积的遗传率较高,说明这3个性状在后代的遗传中受环境因素造成的表型变异小,可以在早期世代进行选育。通过对叶部相关性状进行遗传分析并掌握其遗传规律,为高丹草新品种的选育提供参考。

In this study,grain sorghum Xinliang 52 and sorghum sudanense-251 with great differences in leaf traits were used as experimental materials to construct F2 generation isolates,investigations on the number of leaves,flag leaf length,flag leaf width,flag leaf sheath length and flag leaf area of each plant were carried out,and the optimal genetic model and heritability of each trait were obtained by principal-multiple gene analysis.The results showed that the number of leaves accorded with Model A_4,which was a negative fully dominant mixed genetic model.Inherited by a pair of major genes,the heritability of the major gene was 54.97%.The flag leaf length was in accordance with Model A_1,which was an additive-dominant hybrid genetic model of a pair of major gene inheritance,and the major gene heritability was 46.25%.Leaf width was in accordance with Model A_1,the trait was controlled by a pair of major genes,in line with the additive-dominant mixed genetic model,and the generalized heritability of the major gene was 51.30%.The optimal genetic model of flag leaf sheath length was Model A_0.There was no major gene inheritance,which was the quantitative trait inheritance controlled by micro-effect and multi-gene.The flag leaf area was in accordance with Model B_1,which belonged to the additive-dominant-epistatic mixed genetic model.Controlled by two pairs of major genes,the heritability of the major gene was 79.34%.Among them,the heritability of flag leaf length was low,indicating that the inheritance of this trait was greatly affected by environmental factors,which was not easy to stably inherit in the offspring,while the heritability of leaf number,flag leaf width and flag leaf area were higher,indicating that these 3 traits had little phenotypic variation caused by environmental factors in the inheritance of the offspring,phenotypic variation is small,which could be selected in the early generations.Through genetic analysis of leaf related traits and mastering its genetic laws,it could provide a reference for the breeding of new varieties of Sorghum bicolor×Sorghum sudanenes.