Agrobacterium
mediated genetic transformation of immature embryo plays an important auxiliary role in the study of gene function and molecular breeding in maize. However, the relatively low genetic transformation efficiency is still the bottleneck of the application of this method, especially in commercial scale production application. In this study, we found that pretreatment of immature embryos with LaCl 3 , a Ca 2+ channel blocker, could improve the infection efficiency of Agrobacterium tumefaciens , increase the proportion of resistant calluses, obtain more positive regenerated plantlets, and finally improve the transformation efficiency in maize. This optimization provides a new direction for improving the efficiency of plant genetic transformation mediated by Agrobacterium tumefaciens .