The impact of humidity on the functional response of Blattisocius Mali (Acari: Blattisociidae) preying on the acarid mite Tyrophagus putrescentiae.

Humidity influences the life table parameters and foraging behaviours of various terrestrial arthropods. The soil mite, Blattisocius mali Oudemans is a potential biological control agent of some acarid mites, moths, and nematodes. In the current study, we investigated the functional response of B. mali preying on the eggs of the mould mite Tyrophagus putrescentiae Schrank (Acari: Acaridae) at different humidity levels between 33% and 92%. To determine the type of functional response, we used logistic regression and a generalized functional response equation suggested by Real. The functional response parameters were estimated using models proposed by Hassell and Cabello et al. Blattisocius mali exhibited Type II functional response at 33% and Type III at other tested humidities (52%, 72%, 82%, and 92%). The potential for prey mortality (α) was the highest, i.e., 0.05923, and the handling time was the shortest, i.e., 0.00463 day, at 92% humidity, indicating the highest efficiency of B. mali at this humidity. Our findings revealed that B. mali was more efficient at higher humidity levels as compared to lower humidity levels. Humidity affected the predation rate and might have played an important role in stabilizing the predator-prey system by shifting the functional response with humidity.