[Transfer of insecticidal protein gene from Bacillus thuringiensis into conventional maize inbred-line mediated by Agrobacterium tumefaciens].

Excellent inbred-lines of maize,340 and 4112, which were used largely in hybridized combination were transformed with Agrobacterium tumefaciens. The immature embryos and their original calli were infected by A.tumefaciens LBA4404 containing plasmid pGBIL04. After 3 days of co-cultivation, the immature embryos and calli were continuously selected on the medium containing phosphinothricin (PPT) for 3 generations, then plants were regenerated. It was proved by PCR analysis that the target Bt gene had been integrated into the genome of regenerated plants. The results showed that fresh original calli from the immature embryos after pre-culture were suitable acceptors. The results also showed that it could increase the frequency of selection by properly lowering the co-culture temperature to 22 degrees .