Study On Maize Recipient Material Screening And Genetical Transformation Efficiency Based On Agrobacterium-mediated Method

At present, Agrobacterium mediate transformation on maize is widely used in the world. There are two crucial aspects on maize transformation process, one is the recipient material and the other is genetical transformation efficiency. In this study,14new inbreed lines were used to choose the suitable recipient material by analysing embryogenic Type Ⅱ callus induction rate, plant regeneration rate and GUS transient expression. Zpm2and zpm5were finally screened for maize transformation system. In the study of mature embryos callus induction, mature embryos callus induction rate could predict the growth status of immature embryos callus and their callus induction showed a positive correlation. To improve the transformation efficiency of maize, the study also compared two infection methods and found that vortex shaking in infection step could exceed the GUS expression of20%than invert by hand. EHA105have more stronger infection ability than LBA4404but generally decreased the transformation efficiency. Before infection step, heat-treatment for immature embryos could improve T-DNA transfer efficiency but different maize genotype have various suitable temperature. The results suggested that the suitable temperature of hybrid Hi Ⅱ was42℃.