No abstract

In Egypt, Saissetia spp. (Coccidae: Coccoidae: Hemiptera) are the most dangerous soft scale insects infesting fruit trees. The aim of this work is to study the ecological aspects of Saissetia spp. and its natural enemies in Egypt. The result indicated that Genus Saissetia Deplanche comprises here by two species These are the soft brown scale, Saissetia coffeae (Walker) and the Mediterranean black scale, Saissetia oleae (Olvier). Genus Saissetia recorded here associated with 14 parasitoid species and 16 predator species. The seasonal abundance of S. coffeae was studied for two successive years from 2009-2010 on olive trees in Northern Coast .The obtained results showed that, the insect population reached maximum during mid September (7728 and 8368/ 60 leaves/30 twigs) in first year and second year, respectively. Numbers by parasitoids Metaphycus lounsburyi (Howard), Microterys flavus (Howard) and Scutellista cyanea Motschulsky and a predator Scymnus syriacus Mars., reached maximum (31,9,3, and19 /60 leaves/30 twigs) during September, July, September and August, in the first year, respectively and 20,8,2 and 15 during September in the second year, respectively. The seasonal abundance of S. oleae was studied for two successive years from 2009-2010 on olive trees in El-Arish. The obtained results showed that, the insect population reached maximum during mid of August (9729/ 60 leaves/30 twigs) in first year and mid of September (6899/ 60 leaves/30 twigs) in the second year. Numbers by the parasitoids, Metaphycus helvolus (Compere), Microterys flavus (Howard) and the predators, Coccinella undecimpunctata L. and Exochomus flavipes Thunb., reached maximum (22,5,8 and 28 /60 leaves/30 twigs) during August, August ,September and August, in the first year, respectively and 24,19,4 and 22 during September in the second year, respectively.

The California red scale, Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) is potentially a severe pest of citrus trees in different parts in Egypt. The aim of this work is to study the biological studies of this pest on the host plants, Citrus sinensis (citrus), Ficus nitida (laurel fig) and Mangifera indica (mango) under different temperatures (18, 24, 30ºC) as well as an annotated list of natural enemies associated with A. aurantii in Egypt. The results observed the host plants and temperatures greatly influenced on the development of A. aurantii. The lowering of the temperature increased the dimension of the California red scale and lengthened the developmental period. The results on host plants, citrus, Ficus nitida and mango showed that the life cycle of A. aurantii, at 30 o C were 49.8±11.31, 68.9±19.30 and 81.3±18.31 days, respectively. These results indicated that A. aurantii prefers citrus followed by Ficus nitida and mango. Twelve species of parasitoids and nine species of predators were collected and recorded, one of them is new record and this is Encarsia lounsburyi (Berlese & Paoli) (Hymenoptera: Aphelinidae).

The pteromalid parasitoid, Scutellista caerulea (Fonscolombe) (Hymenoptera: Pteromalidae) is one of the most effective parasitoid associated with soft scale insects. This work dealt with the biological role of this parasitoid during 2009 and 2010 in Egypt. The results indicated that the parasitoid, S. caerulea was emerged from 8 species of soft scale insects. The host soft scale insects were Ceroplastes floridensis Comstock, Ceroplastes rusci (L.), Coccus hesperidum L., Kilifia acuminata (Signoret), Parasaissetia nigra (Nietner), Saissetia coffee (Walker), Saissetia oleae (Olivier) and Waxiella mimosae (Signoret) (Hemiptera: Coccidae). Population abundance studies of S. caerulea were carried out on the aforementioned soft scale insects in eight locations in Egypt, being Beni Seuf, Gharbiya, Giza, Ismailia, Marsa Matruh, Northern Coast, Qena and Sharqiya. The highest rate of parasitism attained with S. oleae was found to be 38.2 and 40.9 % during the first and second years, respectively. While average parasitism rates was 21.3 and 23.5 % during the two years under consideration, respectively. The results indicated that S. caerulea was the effective parasitoid attacking some soft scale insects in Egypt.

Scale insects are the major pests infesting apple, apricot and pear trees in Egypt. The aim of the present work is to study a survey of scale insects infesting apple, apricot, pear trees and their abundant parasitoids in Egypt. A survey of scale insects infested apple, apricot, pear trees and their abundant parasitoids were carried out all over Egypt during 2009-2011. The results indicated that apple, apricot and pear trees were infested by 19, 10 and 10 scale insect species and associated with 12,6 and 8 parasitoid species, respectively.