اثرات زیرکشندگی کنه‌کش بایو-2 بر پارامترهای دموگرافی کنه دولکه‌ای Tetranychus urticae Koch (Acari: Tetranychidae)

Two-spotted spider mite is one of the important pests of crops and greenhouses. The use of chemical acaricides to control this polyphagous pest leads to a decrease in the population of natural enemies, resistance and environmental pollution. Therefore, low-risk herbal compounds such as Bio-2 (Sophora alopecuriodes) can be a suitable alternative. In this study, the sublethal effects of Bio-2 was investigated on the demographic parameters of T. urticae. The experiments were carried at greenhouse conditions 25 ± 5 °C, 60 ± 5% RH and a photoperiod of 16:8 (L:D) h. Bioassay tests were performed by leaf immersion method. The data were analyzed base on a two-sex life table. The sublethal concentrations (LC10 and LC30) were estimated 145 and 330 ppm, respectively. The result showed that the adult longevity of both sexes, fecundity and oviposition significantly reduced for mites treated with LC30. The value of intrinsic rate of increase (r) was 0.2097 day-1 in LC10 and this was reduced to 0.1713 day-1 in LC30 concentration. The finite rate of increase (λ) were 1.186 day-1 for the mites treated with LC30. The net reproductive rate (R0) was 25.26 (offspring/individual) at LC10 and 11.72 (offspring/individual) in LC30 concentration. The recorded period for the mean generation time (T) was variable from 15.39 days at LC10 to 14.36 days at LC30 concentration. In general, it can be concluded that Bio-2 as plant compound reduce use of chemical acaricides and populations of T. urticae, so this plant acaricidae can be used in integrated management of this pest.