RESUMEN
Maize is an important food crop in the world, but the yield and quality of maize have been significantly reduced due to the impact of insect pests. In order to address this issue, the cry1Ah gene was subjected to error-prone PCR for mutagenesis, and subsequently, the mutant cry1Ah-1 gene was introduced into maize inbred line GSH9901 callus using the Agrobacterium-mediated method. The T2 generation transformed plants were obtained by subculture, and 9 transgenic positive plants were obtained by molecular detection which was carried out by PCR, qRT-PCR, Bt gold-labeled immunoassay test strips, Western blot and ELISA. It was found that the Cry1Ah-1 gene could be transcribed normally in maize leaves, of which OE1 and OE3 had higher relative expression levels and could successfully express proteins of 71.94 KD size. They were expressed in different tissues at the 6-leaf stage, heading stage and grain-filling stage, and could ensure the protection of maize from corn borer throughout the growth period. The biological activities of OE1 and OE3 were tested indoors and in the field, and the results showed that in indoors, the corn borer that fed on OE1 and OE3 corn leaves had a mortality rate of 100 % after 3 days; in the field, OE1 and OE3 had strong insecticidal activity against corn borer, reaching a high resistance level. In conclusion, the transgenic cry1Ah-1 maize has a strong insecticidal effect on corn borer, and has a good prospect of commercialization.