BIOLOGICAL CONTROL OF TETRANYCHUS URTICAE Koch ON SWEET PEPPER PLANTATIONS IN A COMMERCIAL FARM BY THE PREDATORY MITE, PHYTOSEIULUS MACROPILIS (BANKS)

Abstract

A commercial farm at Abo-Sower district (Ismailia governorate, Egypt) was chosen for large scale producing and releasing the predatory mites Phytoseiulus macropilis (Banks) for controlling the two-spotted spider mite, Tetranychus urticae Koch on sweet pepper plants under three screen-houses in the same farm. Four screen-houses (6.5m width x 40m length x 2m height) were established for producing both of the prey and predator individuals. Augmentative releases of the predator were applied on commercial sweet pepper plantats cultivated under three screen-houses (each of about 10 feddans) in the same farm to control the two-spotted spider mites T. urticae. The first greenhouse considered as a summer and autumn season, while the second and third screen-houses as winter and spring season. The predator was released with a rate of about 3-5 predators' individuals / pepper plant (about 60000-100000 predators/feddan). Weekly counts of moving stages of the predatory mites, P. macropilis and the two-spotted spider mite, T. urticae and also the native predatory mite, Amblyseius swirskii (Athias-Henriot) were estimated in the field. In the summer and autumn season the T. urticae densities remained more less the economic threshold levels, while in the winter and spring season the spider mite infestations were near or relatively higher on many hot spots. The foregoing results indicated the possibility of large scale producing and releasing the predatory mite, P. macropilis to control spider mites on sweet pepper plants under screen houses in commercial plantations. Additional predator releases were usually required to reduce the pest population, especially in the hot spot areas.