Expression and Functional Analysis of Cry2AX1 Gene in Insect Resistant T₃ Progeny Cotton Plants

Lepidopteran pests pose serious threat to cotton production. A synthetic cry2AX1 gene was used with a view to develop transgenic cotton plants resistant to lepidopteran insect pests. The presence and expression of cry2AX1 gene in T₃ progeny plants were analyzed by Southern blot hybridisation, qRT-PCR, ELISA and insect bioassay. The expression of Cry2AX1 protein ranged from 0.657 to 1.224 μg/g of fresh leaf tissue in the selected T₃ progeny. The detached leaf disc bioassay recorded a mortality of 43.33 to 86.66 per cent against H. armigera. These results indicated that the expression of chimeric cry2AX1 was stable and T₃ transgenic cotton progeny possessed insecticidal activity against H. armigera.