Ecological Studies On Certain Insect Pests Infesting Guava Orchards And Their Associated Predatory Insects At Mansoura District In Egypt

• Hala. A. El- Serafi1; A. A. Ghanim1; A. H. El-Heneidy2 and M. K. El-Sherbenie2
• ¹ Dept. of Economic Entomology, Faculty of Agric., Mansoura University, Mansoura, Egypt.
• ² Plant Protection Research Institute, ARC, Giza, Egypt.
• The first Arab Conference of Applied Biological Pest Control, Cairo, Egypt, 5-7 April 2004.

Abstract

Field experiments were conducted at a guava orchard located at the Experimental Research Farm, Faculty of Agriculture, Mansoura University for the two successive years 2000 and 2001 to survey and study the population densities of the most common insect pests and their associated predatory insects inhabiting guava trees. Twelve insect species belong to the two orders: Homoptera and Diptera were recorded at the experimental area, i.e., Coccus hesperidum L., Pulvinaria psidii Mask ; Ceroplasts floredensis Comst ; Coccus elongates Sign ; Hemiberlesia latania Sign ; Icerya seychellarum ; Icerya aegyptica Dogul ; Empoasca lybica De Berg; Empoasca discipiens Paoli ; Aphis gossypii (Glov.); Ceratitis capitata Weid and Bacterocera zonata (Sounder). C. hesperidium was the dominant species. Nine predatory insect species were recorded associated with the injurious pests infesting guava trees. Population densities of the major insect pests and their associated predatory insects were studied during the two years. The temperature and relative humidity had exerted effect on correlation degrees varied from highly significant positive to significant negative effect on the population densities of the injurious insects and their associated predators during the two years of the study.