空间环境诱导小麦变异及ISSR多态性研究

为探讨空间环境诱变对小麦农艺性状和分子水平变异的影响,本试验对实践八号返回式育种卫星搭载的3份普通小麦品种(系)干种子的SP1农艺性状变异和SP4、SP5选系的ISSR分子标记多态性进行研究。结果表明,空间环境诱变后小麦SP1农艺性状与野生型差异明显,不同小麦基因型对空间环境诱变的敏感性不同。突变系与野生型的遗传相似系数介于0.8226~0.8777之间,与野生型相比,突变系在多个位点发生了DNA水平上的改变。突变系与野生型之间的Nei's遗传距离和各品种对空间环境诱变的敏感性结果不一致,其可能原因是人工选择增大了突变后代中有利变异的频率。综上,空间环境诱变引起了小麦分子水平的变异,这为我国小麦的空间育种提供了一批优异的育种材料。

Space Environment Induced Mutations and ISSR Polymorphism in Wheat

To evaluate the effect of space environment mutagenesis on agronomic traits and molecular-level variation in wheat,this experiment investigated the agronomic traits in the SP1 generation and polymorphism of inter simple sequence repeat (ISSR) markers in the SP4,SP5 generations of three wheat cultivars (lines) carried by the recoverable satellite Shijian-8.The results showed that:After space environment mutagenesis,the agronomic traits of SP1 generation were significantly different from those of the wild type,and different wheat genotypes showed differential sensitivity to the space environment mutagenesis.The average genetic similarity index for the mutant lines and the wild type ranged from 0.8226 to 0.8777.At the DNA level,multiple loci in the mutants differed from those in the wild type.The inconsistent results of the sensitivity to space environment of SP1 and Nei's genetic distance between the mutants and the wild type may be explained by the high frequency of advantageous mutations resulting from artificial selection.Overall,this study illustrated that the space environment mutagenesis can induce mutations on molecular level in wheat,and can provide several excellent breeding materials for space breeding of wheat in China.