The present work was carried out to evaluate the toxicity of
jٍur pesticides i.e. Abamactin, Bijenazte, Spinossad and Beauvaria
bassiana against Tetranychus urticae Koch and predator mile
comparing with release the predator mite, Phytoseiulus persemilis
Athias-Henroit on Cucmber plant, Cucumis sativus that were
assessed in greenhouse. Fabcomic, Acrainite, Tracer and Biovar
were much less toxic to adult females and immature of P. persimilis
than to those of T. urticae. Chemical pesticides gave its maximum
reduction after 3 days from treatment, 86.04, 72.61 and 76.52%,
respectively for Fabcomic, Acramite and Tracer, while Biovar was
the least. On the other hand releasing of P. persimilis at level 1:10
gave the best results of bio-control T. urticae infesting cucumber
plant where it gave 26.09% reduction after 3 days from released and
the reduction percentage increased gradually until reached its
maximum values after 14 days with 88.41%. These results were
nearly similar to those gave by other pesticides. P. Persimilis
significantly affected by feeding on treated prey where longevity and
jècundity decreased.
Conclusively, the predatory mite, P. persimilis introduced
good results in controlling the two-spotted spider mite, T urticae on
cucumber plants in green houses. So, it can use as a biocontrol agent in
controlling this dangerous mite pest on other plants, but it wouid be
appear that conjoint use of the tested pesticides with P. persimilis in IBM
have be sequence separated by time intervals that would be sufficient to
minimize the toxicity effects on the predator.
Key words: Phytoseiulus persimilis. Tetranychus urticae, Pesticides,
Biological control.
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