Overwintering of phytoseiid mites (Parasitiformes, Phytoseiidae) on hazelnut (Corylus avellana) in Sicily (Italy)

Abstract

A study was conducted on the overwintering of predatory mites on hazelnut at two different altitudes (500 and 1000 m a.s.1.). The most common species encountered during two successive winters were Kampimodromus aberrans, Typhlodromus intercalaris and Typhlodromus cryptus. At both altitudes, all three species overwintered predominantly as non-ovipositing female. At 500 m a.s.l., the first young stages of K. aberrans appeared in the second half of April, while no young stages were found until May at 1000 m a.s.l. A few males and young stages of T. intercalaris were found at 500 m a.s.1., no young stages were found at 1000 m a.s.l. Compared to T. intercalaris, more males and young stages of T. cryptus could be observed at 500 m a.s.l. — at 1000 m a.s.l., only a few males were collected and young stages were completely absent. The calyces of the insemination apparatus of overwintering females of the three species were usually found empty. Ten percent of the females at 500 m a.s.l. showed remnants of spermatophores and only few females had an intact spermatophore inside. At the higher altitude the situation was similar, but the number of females containing spermatophores or their remnants was smaller.