Transgenic Rice Plants To Improve Resistance Of Sheath Blight

Rice sheath blight is one of the most important diseases of rice caused by Rhizoctonia solani. The disease has become more and more severe, even becoming the most inportant disease in certain areas, for short of resistant cultivars. However, today, transgenic technique has been widely used to cultivate resistant varieties,. In order to reduce the severity of the disease, different kinds of genes were used to improve rice resistance to R. solani in this paper. Firstly, we chosen gene MGG-08054.5 which from the Magnaporthe grisea, encodes chitinase. It has been demonstrated that MGG-08054.5 encodes a chitinase with strong activity. In addition,we also focused our study on the OXD gene which encodes oxalate oxd decarboxylation enzyme. Previous research has demonstrated that OXD improved Arabidopsis thaliana's resistance to Sclerotinia sclerotiorum, which produces of oxalic acid as well as R. solani. Further more, it has been reported that co-transformation of the chitinase gene andβ-1,3-glucanase gene into a plant can improve its resistance to diseases. Therefore, aβ-1,3-glucanase gene (GLU) from Oryza sativa japonica was cloned.Three plant expression vectors, pCAMBIA1301-ubi-chi, pCAMBIA1301-ubi-glu and pCAMBIA1301-ubi-oxd were constructed and transformed into Minghui 86 and kitaake cultivar mediated by Agrobacterium tumefaciens. The results of PCR assay and GUS dying showed that chitinase and oxd genes have been transformed into rice plants successfully. The RT-PCR assay further confirmed that target genes have been transformed into rice plants. Moreover, the resistance of transgenic plants to R. solani were increased. In addition, pCAMBIA1301-ubi-glu and pCAMBIA1301-ubi-chi co-transformation work also has been done and some transgenic rice plants are coming out soon..The transgenic plants obtained here may be used to rice resistance breeding in the future.