TY - JOUR JF - Acarologia T1 - A five year study on population fluctuations of phytoseiid mites in a citrus orchard in Sicily VL - 27 IS - 3 SP - 193 EP - 201 PY - 1986 SN - 0044-586X SN - 2107-7207 PB - Les Amis d'Acarologia AU - Ragusa, S. UR - https://www1.montpellier.inrae.fr/CBGP/acarologia/article.php?id=2634 DA - 1986-07-28 KW - population study KW - phytophagous KW - predators KW - citrus KW - orchard KW - Italy AB - From 1979 to 1984 a study was carried out in a citrus orchard in the surroundings of Palermo (Italy), in order to ascertain both the species of phytophagous and phytoseiid mites associated with citrus trees, and their fluctuations in populations. Two species of phytophagous mites were found: the two-spotted spider mite, Tetranychus urticae Koch, and the citrus bud mite, Eriophyes sheldoni Ewing. Eighteen species of phytoseiid mites were collected, the most dominant being Amblyseius stipulatus Athias-Henriot. It was followed by five more frequent species such as Typhlodromus rhenanoides Athias-Henriot, Typhlodromus exhilaratus Ragusa, Typhlodromus athenas Swirski and Ragusa, Typhlodromus cryptus Athias-Henriot, and Seiulus amaliae Ragusa and Swirski; the remaining species were seldom collected. Population of A. stipulatus usually showed peaks during summer months; ebbs were inconsistent. Population of other phytoseiids were almost a!ways at a lower level. Sometimes population of A. stipulatus showed a breakdown apparently due to special climatic conditions, such as ’scirocco’ (a hot wind from Africa). Population of T. urticae was scarce; population of E. sheldoni was sometimes present to sorne extent. ER -