大豆对豆卷叶螟抗性的主基因+多基因混合遗传

Mixed Major-gene plus Polygenes Inheritance Analysis for Resistance in Soybean to Bean Pyralid (Lamprosema indicata Fabricius)

豆卷叶螟为南京地区大豆的主要食叶害虫。研究大豆对豆卷叶螟抗性的遗传规律,为其抗性机理研究、QTL初级与精细定位、抗虫育种和分子标记辅助选择育种奠定基础。为此,在田间自然虫源条件下,以溧水中子黄豆和南农493-1正反交组合的F2群体为材料,F2单株叶片损失率为抗性鉴定指标,应用亲本、F1和F2四个世代的数量性状主基因+多基因混合遗传分析方法,分析了大豆对豆卷叶螟抗性的遗传规律。结果表明,大豆对豆卷叶螟的抗性由两对加性-显性-上位性主基因+多基因混合遗传模型控制,主基因遗传率为62.93%,且两对主基因间存在互作。因此,大豆对卷叶螟抗性符合2对主基因+多基因的遗传模式,说明大豆对不同虫源的抗虫性性状存在相似的遗传规律。

The bean pyralid （Lamprosema indicata Fabricius）is one of main leaf-feeding insect species in Nanjing area. The inheritance for resistance of soybean to bean pyralid may provide the foundation for its mechanisms, coarse and fine mapping of quantitative trait loci （QTL） ,breeding of resistance and marker assisted selection to leaf-feedlng insects. Therefore,joint segregation analysis of P1, F1 , P2 and F2 populations derived from a cross between Lishuizhongzihuang and Nannong 493-1 in soybean was used to study the inheritance in this article. Each plant of the four populations mentioned above was further examined for its resistance to natural population of bean pyralid in the field according to its defoliation percentage per plant in 2006. There was no difference in the F2 populations of the original and reciprocal crosses, so that there was no maternal effect and the two F2 populations were incorporated in the joint segregation analysis. The results indicated that the resistance was controlled by two additive-dominant-epistatic major-genes plus polygenes,major- gene heritability is 62.93%, and the interaction between the two major genes was also detected. Therefore, soybean resistance to bean pyralid accords with two major genes plus polygenes and is similar to that of dissimilarity leaf-feeding insect species.