Establishement And Application Of Agrobacterium Tumefaciens-Mediated Transformation System For An Elite Indica Cultivar Zhehui7954

Rice is one of the most important food crops in our country and even in the world, ranking in the third of the crop yield worldwide. Nearly half of the global population lives on rice. Yield improvement of rice is of a very important strategic significance for the future global food security. However, most rice cultivars are sensitive to some diseases and pests such as rice blast, bacterial leaf blight and stem borer, which are the factors limiting the improvement of rice yield and quality. Biotechnology is the first choice in the rice pest and disease resistance breeding program because it can not only lower the cost of rice production, but also reduce the environmental pollution caused by the overuse of chemical pesticides.Zhehui7954is an elite indica rice restorer line with strong restoring force and combining ability. In this study, the blast resistant gene OsLSDl, OsBSRl and the insecticidal gene Bt were introduced into Zhehui7954by Agrobacterium-mediated transformation. The main results are as follows:1. The transformation system of Zhehui7954was developed and optimized. The effects of different ingredients of culture media on the growth of callus generated from the mature embryo of Zhehui7954, and on the plant regeneration were investigated. Consequently, the medium Y1, J3, D6were the optimal choice for callus induction, resistance selection and differentiation, respectively. Under this condition, the efficiency of the gfp gene transformed into Zhehui7954was25.6%.2. The rice blast resistant gene OsLSD1, OsBSRl and the insecticidal gene Bt were introduced into Zhehui7954using the established transformation system and a single Ac/Ds vector removing the selective markers. The target genes were detected by PCR in the transgenic To lines of Zhehui7954, indicating the genes of interest were successfully integrated into the genome of Zhehui7954.3. Zhehui7954-OsLSD1transgenic T1lines were screened by PCR. Fifteen plants without selective markers were identified from two independent transgenic T1lines. This result indicated that the single slective marker-free Ac/Ds vector is suitable for transgenic breeding of indica rice.