Efficacy of Trichogramma chilonis ishii against lepidopteran pests and age of host eggs

Out of 30 eggs exposed to Trichogramma chilonis significantly maximum number of eggs of Helicoverpa armigera were parasitized of 22.22 eggs followed by Spodoptera litura (18.78 eggs) and significantly lower in Papilio demoleus (7.11 eggs). Less parasitized eggs were recorded in P. demoleus due to its large size of egg (0.82 mm²) as compared to H. armigera (0.23 mm²) and S. litura (0.30 mm²). Similarly, % parasitization was also found maximum in case of H. armigera (65.1%) followed by S. litura (59.2%) and significantly lower in P. demoleus (22.9%). Significantly maximum parasitization (60.3%) was noticed in fresh eggs of 24 hrs old followed by 48 hrs old eggs (49.5%) while, 72 hrs old eggs were less preferred (37.3%) by T. chilonis for parasitization. Superparasitization was observed in case of P. demoleus and on an average 10.59 adults of T. chilonis/egg were emerged out. However, the different lepidopteran pests as well as age of host eggs did not show significant differences pertaining to % adult emergence. Fresh eggs of 24 hrs could produce more female progeny of T. chilonis (52.9%) compared to old age of 72 hrs (48.7%).