Potential use of egg parasitoids, Trichogramma pretiosum riley and Trichogramma chilonis Ishii against brinjal shoot and fruit borer, Leucinodes orbonalis Guenée

The parasitizing efficiency and emergence rate of the egg parasitoids, Trichogramma pretiosum and Trichogramma chilonis on one-day, two-day and three-day old eggs of Leucinodes orbonalis was studied under laboratory condition during three different seasons at Bio-control Laboratory of Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, India. The parasitizing ability of T. pretiosum reproduced through parthenogenesis reproduction in three different seasons was also investigated in a similar manner. No parasitism of L. orbonalis was observed by T. chilonis whereas, T. pretiosum expressed maximum parasitism. The findings clearly described the vulnerability of T. pretiosum to weather conditions that exist in the summer season. It was noted that the parasitoid, T. pretiosum preferred one-day-old eggs of L. orbonalis for parasitism during all seasons. T. pretiosum also expressed parthenogenesis reproduction to parasitize the eggs of L. orbonalis. The results indicated the usefulness of T. pretiosum in parasitizing eggs of L. orbonalis.