SITUDIES ON THE NATURAL ENEMIES OF SCALE INSECTS INFESTING SOME FRUIT TREES

Abstract

The scale insects are important pests of fruit trees in Egypt. They cause defoliation, drying up of young twigs, poor blossoming, premature droppinglof heavily infested fruits and small size of fruits together with lack of juice in case of I' heavy infestation. 1 i The main objective of this work was to study the following aspects: I (1) Survey of natural enemies of certain scale insects infesting fruit trees in Be\li-

Suef Governorate . I (2) Ecological studies on the California red scale, the Oriental yellow scale and the I Florida red scale from April, 15th 1995 till April, 1st 1998. I (3) Field studies to evaluate the role ofparasitoids in suppressing the populationiof the California red scale, the Oriental yellow scale and the Florida red scale and studying the rate of parasitism and percentages of total mortalities on these scale . . I msects.

; . I (4) Biological studies on two parasitoids, Aspidiotiphagous citrinus afd

Habrolepis pascuorum which were found during the survey parasitized on the

Oriental yellow scale, especially that, the ecological and biological information about the Oriental yellow is lacking in Egypt. The obtained results were summarized as follows.

1. The natural enemies of certain scale insects:

control I I

The following entomophagous insects and predacious mites were recorded on the following scale insects.