Construction Of Genetic Transformation System And Transgene For CMVcp In Pepper (Capsicum Chinense Jacq.)

Pepper (Capsicum annuum L) is one of the most important vegetables for its rich nutrient with fruit and economic value. Severely attacked by many diseases,it has being studied in order to improve its resistance. Biotechnology brings us the new way to get to the target,for example,by transferring the disease-resistant gene into pepper. In recent years,many researchers have done pepper genetic transformation,but little success. The biggest problem in pepper transformation is the difficulty on the regeneration of the transgenic plants. We made a systematic study on the effect of medium components and physiology condition of explants on plant regeneration,and established the system of pepper(Capsicum chinense Jacq.) plant regeneration. Following these work,we studied some conditions and methods of pepper transformation,and established the system of pepper genetic transformation.The regeneration capabilities of cotyledon with different age are different and the cotyledon with 12-16 days old gives the highest rate of differentiation. 12-16 days old is recommended to get explants. Hormone plays an important role in pepper regeneration. 6-BA is better than ZT for differentiation, and 5mg/L 6-BA+1mg/L IAA gives the highest rate of differentiation. AgNO₃ plays an important role in controlling the browning of cotyledon explants, and 6mg/L AgNO3 is recommended. 5mg/L 6-BA can't result in the elongation of shoots, and 3mg/L6-BA is recommended. GA₃ is necessary for the elongation of shoots and 4mg/L GA₃ is recommended. By systematic studies, we found the high efficient mediums for pepper(Capsicum chinense Jacq.) regeneration: differentiation medium(MS + 5mg/L 6BA + 1mg/L IAA + 6mg/L AgNO₃); elongation medium(MS + 3 mg/L 6BA + 1mg/L IAA + 6mg/L AgNO₃ + 4mg/L GA₃); rooting medium(MS+IAA 0.5 mg/L).pBI121/CMVcp was constructed and then transformed to Agrobacterium tumefaciens EHA105. cotyledon was first pre-cultured on shoot regeneration medium for 2 days, then co-cultured on original shoot regeneration medium with Agrobacterium tumefaciens EHA105 strain carrying CMVcp. After getting rid of the Agrobacterium tumefaciens...