Panonychus ulmi (Koch) and Bryobia rubrioculus (Scheuten) are very serious pests on apple trees in Lebanon. The effectiveness of M2060 (2 fluoroethyl (4-biphenylyl) acetate), Ovamort, Diotol, Genite, and Citronol plus parathion was investigated on the winter eggs of these two mites in the laboratory and in the field. M2060-oil was highly effective and superior to all products at early and late dormant stages of tree growth. The nearer to egg hatch the other products were applied, the more effective they were.

Though they may hatch on any part of a housefly (Musca domestica L.) pupa, most larvae of Nasonia vitripennis (Walk.) and Muscidifurax raptor G. & S. (Hymenoptera: Pteromalidae) move to the host’s ventral abdominal area, and those of Spalangia cameroni Perk. (Hymenoptera: Pteromalidae) to the dorsal side of the abdomen, before feeding extensively. As many as 25 larvae of N. vitripennis can mature on a medium-sized housefly pupa; if more are present initially, those that hatch last usually die from starvation after the host has been consumed. In contrast, usually only one larva of M. raptor or S. cameroni matures on a host; this is often the larva that hatches first, because it attacks all parasite eggs that it encounters while moving over the fly pupa soon after hatching. Larval crowding in M. raptor or S. cameroni, unlike that in N. vitripennis, does not affect the sex ratio of the survivors.