玉米杂交种母本自交系的SSR快速鉴定技术

实验以10个我国主要玉米杂交种的正反杂交组合为材料,分别提取杂交组合果皮、种胚以及母本自交系植株叶片的DNA。每一个正反交组合选取10对多态性SSR引物,对正交组合的母本、正交组合果皮、反交组合母本、反交组合果皮和杂交种F1种胚的DNA进行扩增。数据分析显示,97.5%杂交组合果皮的SSR标记带型呈纯合单一带型,与其母本相同;有2.5%杂交组合果皮DNA扩增出双带型,与杂交种胚相同。根据重复分析结果推测,这可能与母本自交系在某些位点处于杂合状态有关。研究结果表明:采用SSR标记分析玉米杂交组合F1果皮DNA,可以快速鉴定出母本自交系的DNA指纹特征。

The Rapid Identification of Maternal Lines of Maize Hybrids with SSR Based Technology

The materials were 20 reciprocal cross combinations of 10 maize hybrids used widely in China. DNA samples were extracted from pericarp of kernels and embryo of maize hybrids, and young leaves of female parents, respectively. Genotypes were examined using 10 SSR primers for each reciprocal cross combination. SSR loci were selected that could be distinguished between all parents genotypes for each hybrid. Sequent female parent, pericarp of non-reciprocal, female parent, pericarp of reciprocal, and embryo DNA of hybrids were generated by PCR. The analysis showed that 97.5% of the alleles revealed by SSR profiles for pericarp tissue of the hybrids were homozygous, which was the same as female parents, however, 2.5% of the profiles showed both female and male contributions to the hybrids and would therefore immediately lead to suspicions that female inbred was heterozygosis in certain alleles before being crossed. These results showed that SSR technology can be reliably used to detect the pericarp DNA of hybrids and rapidly identify the DNA fingerprint characteristics of the maternal parents of a maize hybrid.