Construction And Identification Of Expression Vectors Containing Genes Resistant To Wheat Fusarium Head Blight

Fusarium head blight(FHB) of wheat caused by Fusarium graminearum is a world fungus disease, it will not only reduce the economic greatly, and the mycotoxins produced by Fusarium endanger the health of human and animal in a large part. The progress of anti-scab breeding for Fusarium head blight was slow due to the lack of resources of natural resistance and the complexity of the pathogenesis. In recent years, RN A interference technology become a new method to the plant resistance research work. In this research, we constructed the transformation-used and gene gun RNAi vectors on the basis of our laboratory, we improve the efficiency of gene transcription by using two promoters to start the gene transcription; we constructed the wheat vectors containing RNAi fragments of Fusarium graminearum key genes to enhance gene silencing and provide materials for genetic transformation of wheat next. The main results are as follows:1. The transformation-used RNAi vectors concluding two promoters for wheat were builded on the basis of the vector which is formerly a monocotyledon expression vector with two T-DNA borders. The double promoters contains two combinations of ubi, cmps, lem2, lem1 and CAMV 35 S, which enhances the expression of foreign genes. The selectable marker gene named UPMI was driven by promoters of ubi, cmps or modified cmpsΩ. At the same time, we build the one-border Agrobacterium-transformation RNAi vector with two promoters ubi and cmps, the selectable marker gene named PMI was driven by promoter of ubi.2. The RNA interference structure was constructed by single fragment or double fragments of single gene, double fragments or multi fragments of multi genes, which was used to construct wheat Agrobacterium-transformation RNAi vectors.3. The single-promoter vectors with two RNAi fragments were bulid for wheat, whitch containing the gene gun expresstion vectors and the Agrobacteriumtransformation expression vectors. The double fragments involve the two combinations of chitin synthase gene Chs7 fragment 3, 4 of Fusarium graminearum and fragment 3 of protein kinase C gene Pkc.4. The vectors were constructed with RNAi fragments gls As3、gls As6 and chs3 b As1 on the basis of the double-promoter vector for Arabidopsis thaliana in our lab, were used to transform the model plant Arabidopsis thaliana for the convenience of study.5. The constructed RNAi vecto rs for anti-scab were transferred into Agrobacterium tumefaciens strain GV3101 by transformation of electroporation, and positive transformants were used to the next wheat transformation.