大豆抗胞囊线虫基因不同世代遗传率的变化

大豆胞囊线虫(Heterodera glycines Ichinohe)是我国大豆的主要病害之一,研究大豆对胞囊线虫的抗性遗传对于培育抗病品种有重要意义。将大豆Essex×ZDD2315组合衍生的后代F2、F2∶3、BC1F2和BC1F4分别接种大豆胞囊线虫1号和4号生理小种,以研究大豆抗胞囊线虫基因不同世代抗性遗传率的变化。结果表明:ZDD2315对1号生理小种的抗性受主效基因控制,未发现多基因效应,在F2∶3、BC1F2和BC1F4世代,主基因遗传率分别为62.15%、72.02%和90.91%;ZDD2315对4号生理小种的抗性受主基因和多基因控制,在F2、F2∶3、BC1F2和BC1F4世代,主基因遗传率分别为65.03%、57.81%、67.76%和95.91%。说明大豆对胞囊线虫1号和4号生理小种的抗性主要受主效基因控制,主基因遗传率比较高,但不同世代检测到的主基因数不同,不同世代主基因遗传率不同,随着世代的提高,主基因遗传率也在提高,因此,育种上高世代选择效果更佳。

Analysis of Heritability of Genes Resistant to Soybean Cyst Nematode (Heterodera glycines Ichinohe) in Different Generations of Soybean

Soybean cyst nematode(SCN) is one of the most important nation-wide soybean diseases in China,study on the genetic rule of soybean resistance to SCN is of great importance to the development of resistant varieties.In the present study,inheritance of resistance to race 1 and race 4 of SCN was analyzed using different generations,F2,F2∶3,BC1F2 and BC1F4 of cross Essex×ZDD2315.Results showed that,in ZDD2315,major genes controlled the resistance to race 1.The heritability of major genes in F2∶3,BC1F2 and BC1F4 were 62.15%,72.02% and 90.91%,respectively.Both major genes and polygene controlled the resistance to race 4 in ZDD2315.The heritability of major genes in F2,F2∶3,BC1F2 and BC1F4 were 65.03%,57.81%,67.76% and 95.91%,respectively.Therefore,SCN resistance of soybean was mainly controlled by major genes.Different number and heritability of major genes were detected in different generations.The heritability of major genes increased in advanced generations.It could be concluded that selecting resistant lines in advanced generations will be reasonable.