大豆对豆卷叶螟Lamprosema indicata (Fabricius)抗性的遗传分析

豆卷叶螟是我国南方大豆的主要食叶性害虫之一, 危害严重。本文在观察豆卷叶螟田间发生情况及其在大豆上特殊的卷叶危害特征基础上, 以虫包数、卷叶率、子粒产量为抗性(危害)指标, 应用3个抗感杂交组合科丰1号×南农1138-2(NJRIKY)、皖82-178×通山薄皮黄豆甲(NJRIWT)和苏88-M21×新沂小黑豆(NJRISX)]衍生的重组自交系群体, 在田间自然虫源条件下于2004—2006年对大豆抗豆卷叶螟的植株反应进行了抗性鉴定。各类指标在各群体均表现有相当大的遗传变异和遗传率, 其中卷叶率指标比其他2类指标遗传变异和遗传率相对较大, 年度间更稳定且与产量的负相关更明显, 因而提出9月上旬卷叶率为鉴定大豆对豆卷叶螟抗性的最佳指标。对NJRIKY、NJRIWT和NJRISX 3个群体抗性遗传分离分析的结果一致表明, 大豆对豆卷叶螟抗性符合2对主基因+多基因的混合遗传模型, 主基因遗传率分别为51.0%、80.5%和56.3%, 多基因遗传率分别为39.1%、11.4%和29.1%。2对主基因的作用方式表现组合间有差异。在此基础上对群体各家系的主基因基因型作了归类, 可供家系抗性选择参考。

Inheritance of Resistance to Lamprosema indicata (Fabricius) in Soybean

Bean pyralid (Lamprosema indicata Fabricius) is one of the major leaf-feeding insects for soybeans and causes serious damage in soybean production in central and southern China. The objective of the present study was mainly to reveal the inheritance of resistance to L. indicate in soybeans using three recombinant inbred line (RIL) populations derived from susceptible by resistant crosses, i.e. NJRIKY, NJRIWT and NJRISX (derived from Kefeng 1 × Nannong 1138-2, Wan 82-178 × Tongshanbopi-huangdoujia and Su 88-M21 × Xinyixiaoheidou, respectively) in the field under natural infestation. Based on the observation of symptoms damaged by the insect on soybeans, rolled leaf percentage, rolled leaf number, and seed yield were examined as resis-tance (damage) indices. Among them, the rolled leaf percentage tested in early September was the best index of resistance to L. indicata due to its higher genetic variation, heritability value and environment-stability, as well as higher negative correlation with seed yield in the three populations. Segregation analyses showed that resistance to L. indicata was dominated by two major genes plus polygenes in the three populations, with their major gene heritability of 51.0%, 80.5%, and 56.3%, and polygene heritability of 39.1%, 11.4%, and 29.1%, respectively. The major gene genotypes of the RILs of the three populations were determined and grouped according to their posterior probability, which could be utilized as reference in selection for resistance lines.