Effect of Host Kind and Egg Treatment by Sub-lethal Concentration of Some Insect Growth Inhibitors on Some Biological Characteristics of Fig Moth Ephestia cautella (Walk) and Currant Moth Ephestia calidella (Guenee) (Pyralidae : Lepidoptera)

The results of this study revealed that the LC50 values of Dimilin 10% E.C, Match 50% E.C and Trigard75% W.P. on eggs of Ephestia cautella (Walk.) and Ephestia calidella (Guenee) were varied according to the host kinds and insect species. Match has a superior value of toxicity ratio and relative efficiency on eggs of E. cautella reaches 100 and 650 % respectively. The eggs of both species treated with sub- lethal concentration of insect growth inhibitors showed an increasing in eggs incubation period and reduction in eggs hatching percentage comprised with the control. The effect of egg treatment expand to the larval stage and increase the larval period, reduce the pupation percentage, elongate the pupal period, reduce the eclosion percentage of the adult and reduce the adult stage period and the number of eggs laid by the female