Insect Predators Associated With Scale Insects and Mealybugs on Navel Orange Trees at Kafr El-Sheikh and Gharbia Governorates

Abstract

Studies were carried out at naval orange orchards, at Kafr El-Sheikh and Gharbia Governorates from April 1 st , 2005 up to March 15 th , 2007. The studies aimed to survey the arthropod predators associated with scale insects and mealybugs. The population fluctuations of these predators were monitored. Biweekly samples of arthropods were taken using a cloth bag (75 cm long) that harboured the sampled branch of a tree. The identified predators were six coccinllieds; Chilocorus bipustulatus L., Exochomus flavipes Thumberg, Rodalia cardinalis Mulsant, Nephus includens Kirsch, (=Scymnus includens) Scymnus pallidivestis Mulsant, S. syriacus Marseal; as well as one chrysopid, Chrysoperla carnea Steph. and the true spider, Cheiracanthium jovium Denis. At both locations, the most occurring predators were C. bipustulatus and Scymnus spp., while the lowest one was Exhochomus flavipes. which peaked on May 1 st , June 1 st and October 15 th , while Scymnus spp. peaked on mid-April and mid-September. Three peaks were recorded for R. cardinalis at early May, mid-September and mid-December.