Feeding habits of overwintered predatory mites inhabiting European vineyards

Biological parameters, prey consumption and prey conversion into egg biomass of overwintered females of the phytoseiids Kampimodromus aberrans, Amblyseius andersoni and Typhlodromus pyri fed with varying numbers of Eotetranychus carpini females or pollen were studied in the laboratory. We found that pollen and E. carpini females proved to be optimal foods for overwintered phytoseiids. In most comparisons pollen induced performances comparable to those recorded when predatory mites were supplied with 4–8 prey per day. Typhlodromus pyri and A. andersoni females survived longer when fed on pollen and the percentage of K. aberrans ovipositing females was higher with pollen than with spider mite prey. For K. aberrans and T. pyri, periods to diapause termination were comparable when pollen or eight prey per predator per day were provided. Oviposition times were long for T. pyri and A. andersoni fed with pollen. Low numbers (1–2) of E. carpini drastically reduced predatory mite oviposition, particularly in A. andersoni that showed high requirements in terms of food biomass. Results highlighted the importance of pollen for overwintered predatory mites. The results obtained can help in understanding some aspects of the biology and behaviour of the three predatory mites in vineyards.