Abstract

Tomato fruit borer, Helicoverpa armigera Hub. is a polyphagous pest which unto 60 per cent yield loss in tomato (Manjunath et al., 1985). Synthetic insecticides are often used to suppress H. armigera population, because of their wide availability and potential for quick intervention. Even though insecticides are effective the demerits like resistance, residue, pest resurgence, non-target effect and environmental pollution restrict their use. As an alternative to insecticides, bioagents are ecofriendly and thus reduce the above mentioned problems. Isolated effects have been made to check H. armigera infestation by using one of the organic farming methods like biocontrol agents. Organic farming produces healthy plants that are better able to resist insect predation. Organic farmer’s primary strategy in controlling pest is prevention through good plant nutrition and management. Biocontrol agents are very important component of organic farming. The important bioagents are: the egg parasitoid, Trichogramma sp. (Mani and Krishnamoorthy, 1983; Divakar, Pawar, 1987 and Kakar et al., 1990), predator, Rhynochorus (Ambrose and Claver, 1999a), pathogens Bt (Krishna et al., 12981) and HaNPV (Natarajan et al., 1991). Even though T. chilonis is highly effective against H. armigera in cotton, but not in tomato. But T. pretiosum is highly effective against H. armigera in tomato. To evallute the potential of T. pretiosum incombination with other biocontrol agents this study was carried out.

Keywords: Helicoverpa armigera, Tomato