Transgenic fertile japonica rice plants expressing a modified crylA(b) gene resistant to yellow stem borer

The japonica rice variety Taipei 309 was co-transformed by particle bombardment of immature embryo-derived embryogenic calli with a modified delta-endotoxin gene cryIA(b) of Bacillus thuringiensis (Bt) under the control of the rice Actin1 promoter, and the hygromycin resistance gene, hph driven by the CaMV35S promoter. Selected transgenic rice plants showed enhanced insecticidal activity against yellow stem borer (Scirpophaga incertulas), with mortality rates reaching up to 100% in a bioassay with cut stems. Introduction and expression of the Actin1 promoter-Bt gene into rice provides japonica rice germplasm resistant to insect attack.