Influence of temperature and prey density of Tetranychus urticae on the functional response of the predatory mite Neoseiulus cucumeris

The current study evaluated the impact of temperature and prey consumption on the functional response of female Neoseiulus cucumeris (Oudemans) when feeding on immature stages of Tetranychus urticae Koch. Six temperatures (16, 20, 24, 28, 32, and 36 ± 1°C) and eight prey densities (9, 18, 27, 36, 45, 54, 63, and 72) were tested over 24 hours in functional response experiments. The type II functional response of N. cucumeris was assessed at each temperature using logistic regression based on the Holling model, and the parameters of searching efficiency (aʹ) and handling time (Th) were determined. The foraging behaviour of this predator was significantly influenced by temperature. Searching efficiency intensified as temperature increased from 16 to 28°C (aʹ=0.720 to 0.797 h-1), with the minimum value at 36°C (aʹ=0.651 h-1). As temperature increased from 16 to 32°C, handling time decreased, reaching a minimum (Th =0.0015 h) at 32°C. Temperature also significantly influenced prey consumption, with the highest and lowest mean numbers of prey consumed being 37.60 and 6.50 at 28 and 16°C, respectively. Predation curves revealed considerable disparity in mean T. urticae consumed across prey densities. These findings can help predict N. cucumeris behaviour and its efficacy for monitoring T. urticae populations.