Some aspects of integrated management to control the pomegranate fruit worm Ectomyelois ceratoniae (Zell.) (Lepidoptera: Pyralidae)

Abstract

The biological efficiency of the parasitoid Apanteles plutellae and the Insect Growth Inhibitor IGR Trigard 75 WP to control the pomegranate fruit worm Ectomyelois ceratoniae(Zell.) was studied. The duration of exposure of the host larvae positively affected the efficiency of the parasite and its biological performance with different exposure durations of 72, 48, and 24 hours. The rate of eggs laid by females also increased directly with increasing time period, as the percentage of larvae infected by the parasite reached 90% at the time period exposure for 72 hours. The number of parasite larvae and pupae produced reached 52.50 and 35.75, respectively, for the same period, while the percentage of infected host larvae was 35.75%. The number of parasite larvae and pupae was 12.00 and 8.0, respectively, at 24-hour exposure period. The IGR Trigard showed a clear effect in the second larval instar, as the rates of cumulative mortality in larvae increased, the duration of the larval instar increased, and the rates of pupation and adult emergence rates decreased with increasing concentrations of the IGR compared to low concentrations. The results showed a direct relationship between the concentration of the IGR Trigard rates with the larvae's mortality, as the highest cumulative mortality rate reached 85.00% after 12 days of treatment at a concentration of 5000ppm. The duration of the larval instar was 4.33 days, the pupation rate was 6.22% at the same concentration, and the emergence rate of adults was 0.00%. As for the effect of the IGR on the fourth larval instar, the highest cumulative mortality rate was 80.00% at the concentration of 5000ppm after 12 days of treatment, which differed significantly from the other treatments, as well as the control treatment, which recorded a mortality rate of 20%. As for the effect on the duration of the fourth larval instar, the results of the statistical analysis indicated that there were no significant differences between the concentrations, and the highest duration was 12.33days, the results of adult emergence were the lowest, 0.00% at the two concentrations of 4000 and 5000 ppm, compared to 90.00% in the control treatment.