SURVEY OF SCALE INSECTS, MEALY BUGS AND ASSOCIATED NATURAL ENEMIES ON MULBERRY TREES IN THE NILE DELTA

Abstract

Sampling of two mulberry tree species namely Morus alba L. and M. nigra L. was conducted from January 2011 to December 2012 to determine the arthropod pests attacking the trees, and their associated natural enemies at Delta region. Two arthropod classes were recorded during the present study (Insecta and Arachnida). Scale insects (Asterolecanium pustulans (Ckll.), Ceroplastes rusci L., Coccus hesperidum L., Saissetia oleae (Bern.), Pseudaulacaspis pentagona (Targ.-Tozz.), Hemiberlesia lataniae Signoret) and mealy bugs (Icerya aegyptiaca (Dough), Icerya purchasi Maskell, Icerya seychellarum (Westw.), Ferrisia virgata (Ckll.), Planococcus citri (Risso), Maconellicoccus hirsutus (Green)) were surveyed as major insect pests. The minor ones were accounted for 24 species (including insects and mites). The parasitoids associated with scale insects and mealy bugs were arranged in five families, Aphytis spp., Encarsia citrina (Crawford), Anagyrus kamali Moursi, Metaphycus sp., Allotropa mecrida (Walker), Scutellista caerulea (Fonscolombe) the most occurring. As for predators, 31 insect species and 9 spiders were found associated with the two pest categories. The predatory mites were identified as two species, which regulate the spider mites. Population fluctuations of mulberry mealy bug, Maconellicoccus hirsutus (Green) were found related to the population fluctuation of Nephus bipunctatus.