Mansour, F., Dept. of Entomology, ARO, Newe Ya’ar Experiment Station, Haifa Post, 31999, Israel

Species presence and density of mixed populations of phytophagous tetranychid and predacious phytoseiid mites were studied in sprayed and unsprayed apple orchards in northern Israel during three growing seasons. Two species of phytophagous tetranychids, namely, Tetranychus cinnabarinus Boisduval and T. Urticae Koch, and two species of predatory phytoseiid mites —Typhlodromus athiasae Porath and Swirski and Amblyseius swirskii Athias-Henriot — were found. Predator density was lower than herbivore density in sprayed commercial orchards, but the reverse was true in unsprayed orchards. © 1990, Springer Science + Business Media B.V.. All rights reserved.