Laboratory study was conducted to study the effect of some new insecticides on three different immature stages of three trichogrammatids and estimate its efficiency in parasitizing eggs of pink bollworm, Pectinophora gossypiella after the completion of its development and emergence. Field Recommended concentrations (FRCs) of three insecticides viz., trebon 30% EC (Etofenprox), cygron 10% EC (Alpha-Cypermethrin- Flufenoxuron), and raner 24 SC % (Methoxyfenozide). The treated trichogrammatids were, Trichogramma evanescens, Trichogramma bactrae and Trichogramma brassicae, and the concerned immature stages at the time of treatment were prepupae, freshly formed pupae and mature pupae (3, 5 and 7-days after parasitism). The study was conducted at 27± 1̊ C, 80± 5% R.H.. Results showed that, the percentage of emergence due to treatments showed no significant differences between the three species of Trichogramma where the total means were; 63.93, 62.17 and 64.11% for T.evanescens, T. bactrae and T. brassicae, respectively. Regardless of the parasitoid species and the treated ages trebon had a severely impact on Trichogramma emergence (48.02%), raner was the least harmful (58.56%) whereas; cygron caused a moderate effect (54.58%). The 3 days age was the less influenced age, as it gave the highest percentage of emergence where, total average was 60.31%) after exposing to insecticides. Regardless the insecticide used, the percentage of adults' emergence was significantly differed by the age of immature stages for each Trichogramma specie, for example, In case of T. bactrae and T. brassicae, the 3 days age gave the higher percentage of emergence which being 56.8& 63.97%, respectively, whereas, 7 days age gave the less percentage of emergence which retched 49.2& 45.03%, respectively, and 5 days age gave the midst percentage which being 51.17& 53.13%.
In contrast of the percentage of emergence, exposing any Trichogramma species at 7 days age (mature pupae) to insecticides had the harmless effect on the percentage of females compared to the other two ages.