Development Of New Wheat Germplasm Resistant To Soil-brone Mosaic Virus By Bombardment

Wheat soilorne mosaic virus (~MV) and wheat yellow mosaic virus (WiMV) are very important soilrone mosaic virus which can cause serious yield lost, even no harvest. Farming practice and chemical control are not sufficient enough to control these diseases. Traditional plant breeding has played an important role in modern agriculture by providing varieties with disease resistance, higher yield and better quality. However, the lack of virusesistance gene in wheat germplasms and the difficulties during the selection procedure limited the progress in virus resistance breeding .Plant genetic engineering provides a new way for developing virus resistant cultivars. In this study we have developed some new wheat germplasms with soilrone mosaic virus resistance gene by bombment. (1) The seven days iurnature embryos call i of yangmai 158 used as receptor to be bombarded with gold particles coated with the WiVib8 target gene and bar selection gene, the two genes were transferred to Yangmail58 by bombardment. After callus induction regeneration and shoot elongation on selection medium with 3mg/L Bialaphos , total of 237 resistant plantlets were achieved .By PCRouthern analysis in the T generation, sixteen transgenic plants were identified with a transformation frequency of 0. 43%. (2) Use the same method, ytV-CPi target gene and bar selection gene were transfeered to Yangmai 158. Total of 145 plantlets resistant to 3mg/L Bialaphos were obtained. By PCRouthern test in T generation, 21 plants were identified being positive .The transformation frequency is 0.99%. (3) Two wheat varieties Lumai 22 and Lumai 23 with high tissue culture ability, were screened from eight corrinercial varieties from Shandong province. They were used as receptor for transformation by bombardment. CV&IVdRpl gene and bar selection gene were transformed to these two varieties. Total of 126 regenerationcalli with greenshoots and a part of transgenic plantlet were obtained. (4) For tracing the alien gene , the T1 plants were tested by PCR and Southern blotting.The results demonstrated that the alien resistance gene was integrated into the wheat genome. But the ratio of T1 plants for Nib8: Nib8 isl: 3.3, for CP14: CP1 isl: 1.3. They were not agreed with Mendel s Law (5) RTCR of 2 plants showed that the alien genes (WYMVib8 and OMV-CP1) had expressed stable. (6) Four transgenie wheat lines with strongly resistance to VMV were obtained by the combination of the molecular test of T1, T2and WYMV field test of T2 in Lixiahe Agriculture Institute of Jiangsu province...