Tomato expressing Cry1A(b) insecticidal protein from Bacillus thuringiensis protected against tomato fruit borer, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) damage in the laboratory, greenhouse and field

Abstract

The fruit borer Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is a serious pest of several crops in India. Among these, tomato, cotton, pigeon pea, and chickpea consistently suffer extensive damage by the insect in different parts of the country. The pesticides no longer control the insect. Among the alternative tactics for its control, transgenic plants expressing toxic proteins of Bacillus thuringiensis offer a sustainable and effective method to prevent the crop losses because of H. armigera attack. The transgenic Bt tomato plants expressing a Cry1Ab protein of B. thuringiensis suffered significantly lower damage by H. armigera than the non-transgenic control plants in the laboratory, greenhouse and field. The Bt plants caused 100% mortality of the larvae and did not support any growth and development by the latter. The only damage caused by the invading neonate larvae was to the terminal parts of tomato shoots, which underwent wilting though larvae died thereafter. In view of this, a complete control of the H. armigera by Bt plants in the field will have to be supported by the other tactics of pest management such as bio-control agents or limited use of pesticides.