Effect of host plants on predation, prey preference and switching behaviour of Orius albidipennis on Bemisia tabaci and Tetranychus turkestani

The anthocorid bug Orius albidipennis Reuter is a generalist predator that feeds on the whitefly Bemisia tabaci Gennadius and the strawberry spider mite Tetranychus turkestani Ugarov & Nikolski in greenhouse crops. There are no previous studies on the potential efficacy of the predatory bug against these pests on greenhouse crops. We report on the efficacy and the prey preference of the predator to control these pests on different host plants under laboratory conditions. In a laboratory experiment, we estimated the predation rates of O. albidipennis at different densities of each prey after 24 h on cucumber and sweet pepper leaves. Predation rates of the predatory bug to T. turkestani and B. tabaci were significantly higher on sweet pepper leaf than on cucumber leaf. We studied the effect of plant species on prey preference and switching of O. albidipennis to B. tabaci and T. turkestani using Manly's α index values and Murdoch's no-switch line, respectively. Our results show that O. albidipennis prefers T. turkestani to B. tabaci on both host plants but its preference for T. turkestani on sweet pepper is significantly greater than on cucumber. Moreover, on sweet pepper, preference values are completely fitted by Murdoch's no-switch line. The findings suggest that morphological defence traits of plants, such as hairy leaves of cucumber, may effectively change prey preference and reduce predation success of O. albidipennis.