Abstract

Using biocontrol agents together with pesticides may improve the success of pest con trol programs while reducing pesticide usage. Effects of the least recommended doses of spirodiclofen (0.18 µl/ml) and azadirachtin (3 µl/ml) on some biological traits of the native predatory mite, Typhlodromus bagdasarjani were studied. In the first experiment egg hatchability was evaluated after dipping into the pesticide concentrations. In the second experiment adult females of the predatory mite were transferred into closable glass cages immersed in the pesticides and supplied with enough immature stages of two-spotted spider mite as prey. Ovipositions of the females were recorded over 13 days. In addition, their predation rates were evaluated for 10 days. Egg hatching rates were 100 and 97.16 percent in azadirachtin and spirodiclofen treatments. An adult female treated by azadirachtin laid an average of 0.49 eggs/day whereas oviposition rate was 0.03 eggs/female/day in spirodiclofen treatment. Females’ adult longevity in both treatments were significantly lower than the control (14.19, 21.07 and 24.19 days in azadirachtin, spirodichlophen and control respectively. After 13 days Azadirachtin and spirodiclofen caused 28.4 and 81.3 percent mortality in adult females, respectively. Daily predation rate in azadirachtin treatment was higher than that of spirodiclofen (11.63 versus 8.59 prey/predator, respectively). As a conclusion, azadirachtin was safer than spirodiclofen for this species and is suggested for IPM programs. Keywords: Side-effects, IPM, Predation rate, Predatory mite