OVIPOSITION BEHAVIOR AND REPRODUCTIVE-PERFORMANCE OF TRICHOGRAMMA-AUSTRALICUM GIRAULT (HYMENOPTERA, TRICHOGRAMMATIDAE) REARED IN ARTIFICIALDIET

Biotypes of Trichogramma australicum were reared on artificial diet '' A'', Helicoverpa armigera (Hubner) (natural host) eggs and Sitotroga c erealella (Olivier) (factitious host) eggs. We evaluated the quality o f these biotypes by comparing their oviposition behaviour and reproduc tive performance on H. armigera eggs. Female T. australicum reared in vitro accepted H. armigera eggs for oviposition and displayed similar behavioural components of oviposition to females reared on natural hos ts. However, handling time during oviposition in H. armigera eggs by f emales from in vitro rearing was significantly longer than handling ti me of females reared on the natural host because the females needed a significantly longer time for host feeding. In vitro reared females pr oduced significantly more progeny and parasitised more H. armigera egg s than the females reared on S. cerealella. Improvements to the artifi cial diet for T. australicum may reduce handling time of the in vitro reared females and increase the female population. These improvements may include changes in nutrient content and size of the artificial egg s.