Mites (Acari) of rubber trees (Hevea brasiliensis Muell. Arg., Euphorbiaceae) in Piracicaba, state of São Paulo, Brazil.

This study determined the main mite species on rubber trees (clone RRIM-600) in Piracicaba, southeast of São Paulo State, from June 2002 to May 2003 and evaluated the possible relation between them. It was conducted in a plantation of 5 ha on 11 year old trees, 15 m high, surrounded with crops as pearl millet, cotton, bean or corn. Samples were taken monthly and consisted of five leaflets, five petioles (only from October 2002 on) and five terminal sections of twigs (10 cm) from 15 rubber trees. All mites of one leaflet, one petiole and one twig section of each plant were mounted for identification to genera/species to estimate the proportional occurrence of each species. A total of 84,850 mites belonging to 38 species of 34 genera and 16 families were found. Tydeidae was the family with the highest number of species (11), followed by Phytoseiidae and Stigmaeidae (4 each). The most abundant families were Eriophyidae, Tenuipalpidae and Tydeidae (totals of 43,023, 26,390 and 13,644 individuals, respectively). The highest population levels of the pest mites Calacarus heveae Feres and Tenuipalpus heveae Baker occurred at the end of the rainy season. The most abundant predators were Metaseiulus camelliae (Chant & Yoshida-Shaul), Amblyseius compositus Denmark & Muma and Euseius citrifolius Denmark & Muma. The predators could not prevent the increase of C. heveae and T. heveae from March on. However, their presence might have prevented an earlier increase and even higher levels of those mites.