**2. Side effects on parasitoid wasps**

Integrated Pest Management (IPM) programs are used worldwide for controlling different agricultural pests. The use of natural enemy agents in combination with selected insecticides, which have no effect on them, is effective in depressing the population density of the pest. Generally, egg parasitoids such as *Trichogramma* have been widely used as biological control agent as reported by Hassan (1982), Bigler (1984) and El-Wakeil & Hussein (2009); who confirmed that 65 – 93% reduction in larval infestations of *Ostrinia nubilalis* in corn fields was achieved following *Trichogramma* releases in Germany and Switzerland as well in Egypt.

#### **2.1. Egg parasitoids**
