Comparative Study Of The Pollen-Tube Pathway Transformation Methods For Melon (Cucumis Melo L.cv Hetao)

In this research, the pollen-tube pathway transformation technique was used in melon (Cucumis melo L. cv Hetao) to study the transformation efficiency of linear and circular expression vectors and expression vectors carrying and not carrying the matrix attachment region sequences. This research has identified the best transforming period, the optimal concentration of exogenous DNA and the appropriate method of dealing with stigma in pollen-tube pathway transformation. The transgenic plants were preliminary screened by the method of leaf painting to select antibiotic resistant plants, and then these antibiotic resistant plants were detected by PCR. The PCR results showed that there were no obvious difference at transformation efficiency of the both linear and circular expression vector, and matrix attachment region sequences can not increase the transformation efficiency. Experimental results showed that transformation of 1～11h after self-pollination can get positive plants and it has the highest transformation efficiency at 5h after self-pollination, while transforming within 24～48h after self-pollination cannot acquire any positive plants. Experimental results of exploring the optimal concentration of exogenous plasmid DNA showed that transformation efficiency of different concentrations has no significant difference. Experimental results of exploring the appropriate method of dealing with stigma showed that cutting whole stigma can get the highest transformation efficiency.In this study, it is cleared that linear and circular expression vectors, expression vectors carrying or not carrying the matrix attachment region sequences don't have significant effect of transformation efficiency. In addition, the study cleared that 5h after self-pollination was the best transformation period. These results provided some references for the application of pollen-tube pathway transformation technology in melon.