The importance of Phytoseius plumifer (Canestrini and Fanzago) in predatory complexes on grapevines during summer drought

Abstract: Species complexes of predatory mites (Phytoseiidae) were studied on grapevines and weeds in vineyards of the Župa vine-growing region, Serbia, in the summer of 2022. A complex of seven Phytoseiidae species was found: Amblyseius andersoni, Euseius finlandicus, Neoseiulella tiliarum, Neoseiulus barkeri, Paraseiulus triporus, Phytoseius plumifer, and Typhlodromus (Anthoseius) rhenanus. Five species were found on grapevines and four species on weeds. The most common species on vines was P. plumifer (C = 88.9 %, D = 98.5 %), and less common on weeds (C = 7.5 %, D = 7.1 %). The most common species on weeds was T. (A.) rhenanus (C = 22.5 %, D = 76.0 %), which was not found on grapevines in this study. The number of phytoseiids on grapevines was relatively high, but the predatory complex was practically reduced to a single species, P. plumifer; moreover, P. plumifer was the only species that had males (9.4 %) and nymphs (12.5 %) in addition to adult females (78.1 %). By examining a large number of temporary mounts, we detected marked ovoviviparity in the species P. plumifer as an adaptation to high temperatures and severe drought. Phytoseiids were rare on the weeds, present in only 35 % of the samples, and T. (A.) rhenanus was the only species that had males (6.2 %) and nymphs (3.1 %) in addition to adult females (90.7 %).