The efficacy of the predatory mite, Phytoseiulus persimilis Athias-Henriot, against Tetranychus urticae Koch, the main
pest of Sweet Charlie and Tamar strawberry cultivars at Behera Governorate, was studied for two successive seasons
2006 and 2007. Results revealed that the reduction percentage of different stages of T. urticae achieved after releasing
P. persimilis at prey-predator ratio of 1/10 & 1/7, ranged between 50-80%. Reduction percentage recorded using
Macomite and Rohmactin approached that of P. persimilis. Results showed that the populations of T. urticae stages
were more abundant on Tamar than on Sweet Charlie cultivars.