Study On Transformation Of Xa21 Gene To Rice Variety Via Agrobacterium

The tissue culture system for elite rice (Japonica) varieties cultivated in Jilin province was optimized. A bacterial blight resistance gene, Xa21 gene was delivered into elite Japonica varieties via Agrobacterium method. Results are as follows:1. The tissue cultural system of mature embryos of elite cultivated rice varieties in Jilin province was optimized. 1.1 The callus induction and differentiation efficiency of different genotypes is quite different. The callus induction efficiency of Changbai 9, Chaochan 2, Fengyou 501, and Fengyou 307 could be as high as 86.4, 88.7, 80.8 and 81.6 percent respectively. And the differentiation efficiency of Changbai 9, Chaochan 2 and Fengyou 501 could be as high as 50.1, 45.8 and 49.5 percent respectively.1. 2 Reducing 2.4-D concentration to 1 mg/L, adding NAA (1 mg/L) and KT (0. 5mg/L) in the subculture medium can improve the growth of callus. And more yellowish, grain-shape embryogenic calli was obtained. 1.3 Drying treatment of calli for 16h before differentiation could increase plant regeneration efficiency by 20.6-37.2 percent.2. Bacterial blight resistant gene, Xa21 was delivered into Japonica rice variety.Using the embryogenic callus induced from rice mature embryo as explant, a bacterial blight resistant gene, Xa21 gene was delivered into Japonica rice variety, Changbai-9, via Agrobacterium. Fertile transgenic rice plants were obtained. Xa21 gene had been inserted into rice genome demonstrated by PCR and Southern hybridization. Gene silence was observed in one transgenic rice plant.