两个广谱抗虫基因源抗性背景DNA的多样性分析

RESISTANT BACKGROUND DNA POLYMORPHISM BETWEEN TWO LEAF FEEDING INSECT RESISTANT SOYBEAN GERMPLASMS

利用８对抗－感大豆叶食性害虫近似等位基因系，１００个随机引物进行ＰＣＲ扩增，在４０６个稳定重现的片段中，有２个在近等基因系间表现多态性；不同抗性来源的两组材料间的多态性ＤＮＡ片段的有／无呈相反趋势，相同抗性来源的材料间的多态性ＤＮＡ片段的有／无也存在差异。由此可以认为，抗性供体ＰＩ１７１４５１，ＰＩ２２９３５８的抗性背景ＤＮＡ的多样性比较丰富，遗传背景相差较大，说明它们的抗性基因来源不同。在进行广谱抗虫育种实践中，为丰富育成品种，尤其是回交育成品种在抗性基因和抗性基因背景ＤＮＡ上遗传多样性，避免其遗传脆弱性，以维持持久的抗性。

pairs of leaf feeding insects resistant/susceptible soybean near isogenic lines(NILs) and 100 randomly selected primers were involved in this RARDs study. Among the 406 repeatable DNA fragments. 2 shew polymorphism between and among the NILs/Parents used in this program. A diverse tendency of the absence/presence of the 2 polymorphic DNA fragments between the two groups of NILs from different doner parents implied the possibility that PI171451 and PI2295358 carry different leaf feeding insects resistance controlling gene(s), and have different DNA background. Therefore, equal integration of leaf feeding insect resistance from PI171451 and PI229358 into soybean varieties are strongly recommended.