اثرات سطوح مختلف کود نیتروژن در لوبیا چیتی بر رشد و باروری کنه تارتن دولکه ای، Tetranychus urticae (Acari: Tetranychidae)

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is one of the important and damaging pests of agricultural products throughout the world. In this research, Chiti bean plants were treated with four nitrogen levels (0, 75, 150, and 225 kg N ha-1). The biological parameters and fecundity of the two-spotted spider mite were evaluated on beans treated with nitrogen fertilizer at 25±1˚C, 60±5% RH and a photoperiod of 16:8 (L:D) h. Data were analyzed based on the age-stage, two-sex life table theory and using TWOSEX-MS Chart program. The paired bootstrap test was used to compare differences between treatments, and figures were obtained using statistical software Sigma Plot 14. Results showed that there were significant differences in duration of different life stages and fecundity of T. urticae on Chiti bean plants treated with different nitrogen levels. Therefore, the total preadult duration of spider mites decreased as the nitrogen fertilization level was increased. The longest value of total preadult duration was obtained in control (8.85 days) and shortest value was in plants treated with 225 kg N ha-1 (7.32 days). There was no significant effect on the duration of protonymph and total lifespan of the spider mite (P > 0.05). The shortest adult longevity was observed on mites reared in control and plants treated with 75 kg N ha-1 and the longest duration was observed on those reared on plants with 150 and 225 kg N ha-1. The highest sxj of adults was 0.55, 0.55, 0.60, 0.58 for females and 0.20, 0.21, 0.21, 0.20 for males in N fertilization levels 0, 75, 150 and 225 kg ha-1, respectively. According to these results, mites reared on plants treated with 150 and 225 kg N ha-1 had the highest value of sxj of female adult stage. Furthermore, fecundity of spider mites was affected significantly by fertilization levels. Fecundity of spider mites increased as the nitrogen fertilization level was increased, and there were 97.90 (eggs/female) at the highest N fertilization level (225 kg ha-1). Consequently, biological performance of the spider mite can be enhanced with increasing nitrogen fertilization.