<p class="Body">Biological responses of Tetranychus urticae (Acari: Tetranychidae) to different host plants: an investigation on bottom-up effects

Abstract

Two-spotted spider mite, Tetranychus urticae Koch, is a cosmopolitan pest causing economic damage to a wide range of different host plants worldwide. In the present study, bottom-up effects of four common greenhouse plants including cucumber (cultivar “Negin”), tomato (cultivar “Isabella”), eggplant (cultivar “Bell”) and watermelon (cultivar “Crimson”) on biological parameters of this pest were evaluated using age-stage, two-sex life table theory. The obtained results revealed that the durations of different life stages of T. urticae were significantly affected by the host plants tested. Accordingly, the highest and lowest recorded values for duration of total immature stages of this mite were recorded on tomato (12.09 ± 0.25 day) and eggplant (8.37 ± 0.16 day), respectively. The duration of oviposition period was also significantly different and the highest value was estimated on watermelon (14.19 ± 1.26 day). Furthermore, host plants tested significantly affected the mortality of different life stages and the highest immature mortality was estimated on tomato (65.31 ± 4.81 %). The highest and lowest estimated values for intrinsic rate of increase (r) were recorded on cucumber (0.239 ± 0.014 day-1) and tomato (0.104 ± 0.016 day-1), respectively. The calculated values for mean generation time (T) were the highest on tomato (17.81 ± 0.53 day) and the lowest on eggplant (13.98 ± 0.28 day). These findings demonstrated that cucumber and tomato had the lowest and highest negative effects on the biological parameters of T. urticae, respectively.