A synthetic cry1Ac gene coding for an insecticidal crystal protein (ICP) of Bacillus thuringiensis (Bt) was transferred to tomato by
cocultivating cotyledonary explants with Agrobacterium tumefaciens. Transformant plants resistant to kanamycin were regenerated.
Hybridization experiments demonstrated gene integration and gene copy number in the transgenic plants. Double-antibody sandwich
ELISA analysis revealed high levels of Bt ICP expression in the leaves of transgenic plants. The expression resulted in a high level of
protection of transgenic plant leaves and fruits against the larvae of tomato fruit borer (Helicoverpa armigera). Limited "eld trial of the
transgenic plants (T1 generation) con"rmed the high levels of insect protection. ( 2000 Elsevier Science Ltd. All rights reserved.