Studies On Chloroplast Genes Genetic Polymorphism Of Rice (Oryza Sativa. L) And Expression Of Chloroplast Genes In Isonuclear Alloplasmic Materials

Rice is one of the world major food crops and more than 60% Chinese take it as their staple diet. Widely grown hybrid rice made a great contribution to the development of food production and food safety. But in recent years, the yield of hybrid rice has been stagnating, mainly because the genetic diversity of the parents of hybrid rice is not high, the difference of genetic background between the CMS and CMS and the male parent and male parent is too small and the relationship is too close. Especially, due to the constraints of cytoplasm resources on three-line hybrid rice, taking Cytoplasmic male sterile line as CMS, the potential of further increase the yield of three-line hybrid rice is becoming smaller and smaller. Therefore, the studies of genetic polymorphism of the hybrid rice cytoplasm and the cytoplasmic effect have great significance. In this paper, using the parents of hybrid rice as materials, rice chloroplast gene genetic polymorphism and its expression in isonuclear alloplasmic materials are studied to promote the understanding of cytoplasmic molecular genetic characteristics and provide theoretical guidance for the selection of the female parent of hybrid rice. 1 Comparison of the chloroplast gene between subspeciesThrough gene sequence analysis, we found there are differences among the 5 chloroplast genes(psbB,rpoc2,ccsA,ndhH,psbA) of four typical indica and three typical japonica in the level of bases, and the differences show a characteristic of regularity between subspecies of Indica and japonica, the sequences of the cpDNA of four typical indica are consistent (known as indica genes), the sequences of the cpDNA of three typical japonica are consistent (known as japonica genes). The base differences between Indica and japonica of different varieties are identical, the cpDNA type of subspecies is consistent with the nuclear genome type and the results show that the five chloroplast genes for research have a significant difference between rice subspecies.The 5 chloroplast gene sequences of Javanica rice Lemont, IM359 are completely identical to typical japonica, it shows that the cytoplasm of Javanica rice are partial japonica in the level of the five chloroplast gene sequences.2 Analysis of chloroplast gene of rice CMS lineThe 5 chloroplast gene sequences of 10 cytoplasm materials of WA, Yinshui type, K type in 11 CMS lines rice are entirely consistent. Compared with other 10 kinds of CMS rice, HL type CMS material Yuetai A has a total of three bases difference in the psbB and ndhH gene. It shows that cytoplasmic inheritance of Yuetai A is different from other 10 CMS lines in the level of chloroplast gene sequences. The results show that CMS lines used for the current production and the genotype of their cytoplasm are mainly WA, the level of cytoplasmic genetic polymorphism is very low.3 Analysis of common wild rice chloroplast geneThe analysis of 5 chloroplast gene sequences of 12 common wild rice show that 5 chloroplast gene sequences of Hepu, Chaling, Dongxiang common wild rice are completely consistent with the indica, and in other 9 kinds of materials there are some base sites are same to indica and others are same to japonica, the chloroplast gene sequences of Gaozhou, Fusui, Liujiang wild rice are completely identical, it shows that the genetic polymorphism of common wild rice is very high, meanwhile, it shows that the chloroplast genome of the wild rice has the trend of indica-japonica differentiation. The result provides an important molecular evidence for the two sources of origin theory of cultivated rice.Three base sites in 5 chloroplast gene sequences of WA-type CMS line are differenent from Hainan Common Wild Rice. Natural sterile plants containing sterile cytoplasm gene, found by Yuan Longping and Li Bihu in Hainan, are not common wild rice in Hainan, but specific genetic variation occurred in the cytoplasm. Sterile gene source of HL is also a specific genetic mutant.4 Expression analysis of the isonuclear alloplasmic chloroplast gene of riceThrough the comparation of expression of chloroplast genes psbA, atpB, rbcL and nuclear gene rbcS in isonuclear alloplasmic rice coming from the group taking indica CMS line ZhunS as nuclear donor, indica Nanjing 11 and japonica Nipponbare as cytoplasm donor, we found that the expression of psbA, atpB, rbcL, rbcS in Nipponbare/ZhunS is higher than those in Nan jing11/ZhunS, but the expression of the four genes in ZhunS of japonica cytoplasm and that in Nipponbare/ZhunS is not significantly different. The results show that genetic background would not affect the expression of chloroplast and nuclear genes.