Creation of new transgenic maize germplasm harboring cry1Ab13 gene

Objective To construct a plant expression vector including a lepidopteran-resistant gene cry1Ab13 and use it to create a new transgenic maize germplasm with high resistance to Ostrinia furnacalis.

Method The cry1Ab13 gene was inserted into expression plasmid pCAMBIA3300-Bar by homologous recombination method, and the plant expression vector pCAMBIA3300-cry1Ab13-Bar with Bar gene as a selection marker was obtained. Following Agrobacterium mediated transformation of the immature embryo of maize inbred line H99, the regenerated plants were detected by PCR and herbicide-resistance selection for each generation. T₂ generation plants were also detected by Southern blotting and real-time quantitative PCR. The resistance of transgenic plants to O. furnacalis was tested indoor and in the fields.

Result A plant expression vector containing the cry1Ab13 gene was successfully constructed and three T₂ transgenic maize with high resistance and one T₂ transgenic maize with resistance to O. furnacalis were obtained. The cry1Ab13 gene was integrated into maize genome as confirmed by Southern blotting, and it was expressed in maize as shown by real-time quantitative PCR.The resistance of transgenic plants to O. furnacalis was improved significantly compared to non-transgenic control.

Conclusion We introduced the cry1Ab13 gene into maize and its expression significantly improved the resistance of maize to O. furnacalis, which will promote the development of new insect-resistant maize germplasm.