Effects of Some Acaricides on Life Table Parameters of the Predatory Mite,Phytoseiulus macropilis Fed on the Two-Spotted Spider Mites

Abstract

The objective of this study was to evaluate the effects of some selected acaricides recommended for the control of the two-spotted spider mites; chlorfenbyer (Challenger ® 36% SC), hexythiazox (Maccomite ® 5% WP) and pyridaben (Pyromate ® 20% WP) on development and life table parameters of Phytoseiulus macropilis (Banks) as an important natural enemy of this pest mite under laboratory conditions. Life cycle duration averaged 8.44, 8.20 and 9.45 days for chlorfenbyer, hexythiazoxand and pyridaben, respectively compared to 5.49 days in the control. The tested acaricides caused a significant reduction in the female longevity and fertility of the predatory mite. The intrinsic rate of increase (r m ) and finite rate of increase (λ) values were significantly lower than those in the control. Mean generation time (T) was 13.32, 14.96 and 13.88 with chlorfenbyer, hexythiazox and pyridaben, respectively, and significantly lower than the control (11.91 days). Pyridaben reduced fertility by 68.64% relative to the untreated control.