The success for genetic transformation of maize (Zea mays L.) is highly related to genotype of target material. A few model varieties can be induced into type Ⅱ callus, which can be easily transformed with high regeneration frequency. However, most of cultivars could be only induced into type Ⅰ callus, which is difficult to be transformed with low regeneration. Thus, studying on the conditions of induction and transformation for type Ⅰ callus will show great importance for improving elite of maize directly with genetic engineering. Bacillus thuringiensis toxin protein (cry1Ac3) gene was successfully delivered into type Ⅰ calli of two elite inbred lines of maize, 340 and E28, via particle bombardment in this work. Fertile transgenic corn plants were obtained through phosphinothricin (PPT) or hygromycin B (HygB) selection, and the results of PCR, Southern blot assay and ELISA showed that foreign genes had been integrated into maize genome and expressed. In the meantime, strong resistance of some transgenic plants to corn borer was showed through bioassay. In addition, the comparison of selective effect between PPT and HygB showed that PPT, as a selective agent, was better than HygB for the growth and regeneration of resistant calli.
