The effect of Beauveria bassiana-treated Trialeurodes vaporariorum on the development, longevity and oviposition rate of the predatory mite, Amblyseius swirskii

The predatory mite, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is an effective predator feeding on different insect and mite pests such as whiteflies, thrips and two-spotted spider mites. This predator and entomopathogenic fungus, Beauveria bassiana are important natural enemies of Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae). In this study, the effect of fungus-infected T. vaporariorum (105 conidia ml-1) on the development, longevity and oviposition rate of the predatory mite in different time intervals (0, 24, 48 and 72 hours) at 25±1°C, 60-70٪RH and a photoperiod of 16:8 h (L: D) under laboratory condition was investigated. The results indicated that developmental period of the predatory mite fed on tween 80-treated T. vaporariorum (Control) and fungus-treated T. vaporariorum (time interval 0) was shorter than other time intervals of infection. The results showed that there were significant differences between the treatments in oviposition rate. It shows unfavorable effect of entomopathogenic fungus by increasing of infection longevity. So, it is better to use A. swirskii and B. bassiana simultaneously.