Study On Tomato Transformation With Brassinolide Synthesis Gene PSC1

Tomato is an important vegetable planting in China widely, but it yields lowly, resistanse poorly and pests seriously,so the tomato breeding never stopped to save this problem. The most videly used of tomato breeding method is conventional breeding and cross breeding, but the existing tomato germplasm resources has been used of. Transform the brassinolide synthesis gene PSC1 into tomato and overexpression,a new tomato species with high yield,high quality and stress resistance will be achived. We have did the follows in order to transform the gene PSC1 into the tomato and expressed successfully:1. Establish the floral-dip transformationBy comparing various transgenic methods, the floral-dip transformation was choosed. The suspension of transformation include Agrobacterium, MS,6-BA and Silwet L-77.In order to infect successfully, the final concentration of suspension components and the Agrobacterium culture time were investigated.5-10 days before flowering, we soaked the tomato inflorescence with suspension and then bagging 2-3 days,then harvest the transgenic seeds for screening.2. Select the appropriate screening methodBy comparing three major screening methods, the dish culture method was choosed. Cultivate the transgenic seeds in the culture dish with the mixture of nutrient solution and 50mg/L Kan,33 positive seeds were choosed. Identified by PCR,it indicated that the foreign gene transformed into tomato.3. Preliminary study of intron enhance gene expressionThis study connect 1542bp PSC1 cDNA and 3105bp DNA with vector pROK2 respectively, p16 and p14 were constructed.Transformed the p16 and p14 into tomato by floar-dip, transgenic plants were obtained,and they were named T16 and T14 respectively. The transgenic plants are taller than the CK and grow better, and the T14 was taller than the T16. This research initially proved that the PSC1 gene intron can enhance the gene expression.