Studies On Agrobacterium-Mediated Transformation System In Rice(Oryza Sativa L.)

Rice (Oryza sativa L.) is one of the most important food crops in the world, and it accounts for about fifty percent of cereal consumption in China. Rice has been considered a model crop for plant genomics studies because of its relatively smaller genome size and explicit definition of genetic background. Agrobacterium-mediated genetic transformation in plants possesses such characteristics as convenience in manipulation, high transformation efficiency, low copy number of introduced genes and simple integration pattern and is therefore greatly applied by researchers. Agrobacterium-mediated gene transfer depends on genotype and regeneration of rice cultivars so it is very helpful that to establish a universal and high efficient system for regeneration and transformation in rice.In this research, three japonica (Oryza sativa L.ssp. japonica) varieties Nipponbare、Zhonghua11and Suyunuo were used for induction of callus derived from young and muture embryo respectively. Several genes, including OsCBL5、0sCBL6、0sNHX2、ZFP177、ZFP181、0sSNAP32、0sNPSN11、0sSYP71et a1cloned from rice by this lab were used for the genetic transformation of rice by the means of Agrobacterium tumefacien-mediated method. The results indicated that the induction rate of embryonic callus from youny embryo was better than from mature embryo in all three japanica varieties, and a local variety Suyunuo has higher induction rate of embryonic callus from youny embryo and mature embryo with95.2%and96.2%respectively. Meanwhile Suyunuo has also higher transformation efficiency of calli and plants of Suyunuo youny embryo was70.5%and52.4%, respectively, significantla better than Nipponbare and Zhonghua11. The possinble mechanism was discussed in this study.