Identification Of Three-line Hybrid Rice And Its Parents By Using DNA Markers

In this research, the characteristic molecular markers that strictly link to cytoplasmic male sterile(CMS) gene and restore gene as well as SSR molecular markers were used to analyze the parents and their combinations of the three lines(CMS lines ,Maintainers and restore lines ). On one hand, the characteristic markers were used to examine characteristically the three lines. On the other hand, the SSR technique was also used to research genomic polymorphism of representative hybrid rice combinations. As a result, some polymorphic fingerprint maps were developed .This research also analyze genetic relations according to the results of SSR molecular markers. The results were as followed: 1. The characteristic primers that strictly link to cytoplasmic male sterile gene and restore gene of WA ,BT ,HL of hybrid rice were amplified in 43 parents of the three lines hybrid rice. The results showed that the characteristic primers that strictly link to CMS genes could distinguish CMS lines from its maintainers in the same type of hybrid rice ;The characteristic primers that strictly link to restore genes could identify restore lines in the counterpart type of hybrid rice. 2. In this research, 180 pair of SSR primers was used to analyze the representative six combinations of WA and two combinations of BT hybrid rice. The results showed that 40 pair of polymorphic SSR primers in WA hybrid rice combinations was selected ;And 27 pair of polymorphic SSR primers in BT hybrid rice combinations was selected. The genetic fingerprint maps were developed according to these primers. By using these maps, we can distinguish rice hybrid from their parents. 3. The characteristic markers could not effectively distinguish hybrid rice with the parents that contain the marker loci that strictly link to CMS gene or restore gene. But SSR Markers can distinguish parents with their hybrid rice easily. Consequently combine these two markers we could identify the parents and its hybrid rice. 4. According to these genetic fingerprint maps of six WA combinations and two BT hybrid rice combinations, the cluster analysis was carried out by using SPSS software. The results suggested that the above-mentioned parents and their hybrids were mostly divided into two clusters. The first cluster contained the parents and hybrid of BT. The second cluster contained parents and hybrid of WA. Among every cluster the CMS lines and their maintainers were generally classfied into one subcluster;The restore lines were generally classfied into another subcluster.