栽培×野生大豆2个重组自交家系群体种子耐淹性遗传分析

Genetic Analysis of Seed Germination Characters under Submergence Stress in Two Recombinant Inbred Line Populations of Glycine max×Glycine soja

大豆播种后遭受洪涝灾害会严重影响出苗率,往往导致减产,选育耐淹大豆品种是防灾避害的有效途径。以种子不耐淹水的2个栽培大豆南农493-1、南农86-4分别与耐淹野生大豆PI342618B杂交衍生的NJRISP和NJRINP重组自交家系群体为材料,研究其在72 h淹水处理下种子耐淹性的变异与遗传。结果表明:淹水条件下供试群体家系间发芽率存在显著差异,遗传变异大。发芽势、发芽率及豆芽根长、芽长性状有较高的遗传率,且各性状之间呈现高度正相关。主基因+多基因分离分析方法分析发现淹水条件下2个群体大豆发芽势和发芽率遗传符合4对主基因模型(H或I模型),主基因遗传率达93%以上,多基因效应较低,耐性等位基因来自野生大豆亲本。野生大豆中蕴含优异耐淹基因资源,可为大豆耐涝育种提供优异基因。

Flooding stress after soybean planting can cause poor seedling stand and consequently yield reduction. Development of soybean cultivars with good waterlogging tolerance is one of the most effective ways to reduce production loss. In the present paper,two recombinant inbred line populations,NJRlSP and NJRINP,derived from the crosses between two sensitive cuhivars Nannong 493-1, Nannong 86-4 and one tolerant wild soybean PI342618B were used to reveal the variation and inheritance of the tolerance to seed-submergence at germination stage. It showed that there were significant differences and high genetic variation in the RIL populations. The heritability values of the germination rate at 3 and 5 d after treatment, root length and sprout length were higher than those of other indicators,and there were highly positive correlations among the four traits. The results from segregation analysis under major genes plus polygene mixed inheritance model showed that the inheritance of germination rate at 3 d and 5 d after treatment fitted four major genes model（ H or I genetic model）. The values of major gene heritability were more than 93 % , and the polygene＇s were relatively low. All the tolerant alleles were only detected in wild soybean, indicaring the existence of elite tolerant genes tor soybean tolerance breeding.