FIELD TRIALS TO EVALUATE THE RELEASE OF THE PREDATORY MITE Phytoseiulus persimilis A. – H. AND THE LADY BUG Stethorus gilvifrons MULSANT IN SUPPRESSING THE POPULATION OF Tetranychus urticae infesting BEAN PLANTS.

Nassar,, O. A.; Fouly, A. H.; Osman, M. A.

doi:10.21608/jppp.2008.217784

FIELD TRIALS TO EVALUATE THE RELEASE OF THE PREDATORY MITE Phytoseiulus persimilis A. – H. AND THE LADY BUG Stethorus gilvifrons MULSANT IN SUPPRESSING THE POPULATION OF Tetranychus urticae infesting BEAN PLANTS.

Document Type : Original Article

Authors

Agricultural Zoology Department, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt.

10.21608/jppp.2008.217784

Abstract

Field trials were conducted at the farm of the faculty of agriculture, MansouraUniversity in order to evaluate the efficacy of the predatory mite P. persimilis and the predatory insect S. gilvifrons in suppressing the population of the two spotted spider mite T. urticae after release of the predacious arthropods in open field cultivated with green beans. Three suggested levels of the predator : prey ratio were used, namely 1:20, 1: 40and 1:60 for both predacious arthropods. The percent reduction in egg stages of T. urticae at the first level was 76.17 and 85.5 for the predatory mite and insect respectively after 25 day of release. While the present reduction in moving stages of T. urticae at the first level was 78.28 and 84.97 for the predatory mite and insect respectively after the same period of the release.