The velvet mite, Allothrombium pulvinum Ewing is a natural enemy of pest species. Larvae of A. pulvinum are ectoparasitic of aphids, whereas deutonymph and adult mites are free living predators of aphids, whereas deutonymph and adult mites are free living predators of aphids, spider mites and other small arthropods. In this study the preference of odult A. pulvinum among five prey species: Aphis gossypii Glov. and Aphis fabae Scop. on cucumber, Hyalopterous amygdali Geoff. on apricot, Macrosiphum rosae (L.) on rose and Tetranychus urticae Koch on cotton leaf discs was determined with non-choice and multiple-choice tests. For measuring the prey preference in multiple-choice tests, we used the Manly’s alpha (α). Functional response of adult A. pulvinum on preferred prey (H. amygdali ) was also examined on apricot leaf discs over a 24-h period. Logistic regression was used to distinguish the shape of the functional response (type II or type III ), and nonlinear least-squares regression was used to estimate attack coefficients (a) and handling time (Th). All experiments were carried out in a growth chamber (25±2˚C, 75±5% R.H. and 12L:12D). In non-choice tests, results showed that the predatory mite preferred H. amygdali than the others (P<0.001). Furthermore, in multiple-choice tests, the preference index (α) indicated that H. amygdali was preferred prey. Results of logistic regression analysis indicated a type II functional response for predation adult of A. pulvinum presented with H. amygdali. Also results of nonlinear least sqare regression analysis revealed that parameters a=0.027±0.003 and Th=2.775±0.260.

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