Prey stage preference and functional response of Orius albidipennis (Hetetroptera, Anthocoridae) to Aphis fabae (Homomoptera, Aphididae)

Abstract

The black been aphid, Aphis fabae Scopoli (Homoptera: Aphididae), is an important pest of many garden, vegetable and ornamental plants in the world. To evaluate Orius albidipennis potential for biological control of the aphid, prey stage preference of the predator to different life stages of the aphid and functional responses of it to different densities of the most preferred life stage were studied under laboratory conditions. Free choice experiment was conducted for evaluation of the bug prey preference between different instar nymphs and wingless female adults of A. fabae. In functional response trials, densities of 5, 10, 15, 20, 25 and 30 s instar nymphs, as the most preferred life stage, per arena were exposed to male and female of the predatory bug for 24-h period. The logistic regression analysis and Roger’s model were used for determinate the type and the parameters of predator’s functional response, respectively. The results showed that O. albidipennis preferred first and second instar nymphs of the aphid in comparison with other life stages. Both sexes of O. albidipennis showed the type II functional response to different densities of the nymphs. The handling times (Th) of O. albidipennis female and male were 1.344 and 1.584 h, respectively. The attack rate value (a) of the female and male bugs were 0.0839 and 1.4814 h−1, respectively. No significant differences were observed between the calculated Th and a for the female and male bugs. From the findings of this study, O. albidipennis can be used in biological control program of A. fabae.