Integrated Control in Citrus Fruit Crops - IOBC-WPRS

Integrated Control in Citrus Fruit Crops
IOBC wprs Bulletin Vol. 29(3) 2006
Natural enemies of the spider mites, Tetranychus urticae Koch and
Panonychus citri (McGregor) (Acari: Tetranychidae) in Spanish citrus
orchards
Raquel Abad, Pedro Castañera and Alberto Urbaneja
Unidad Asociada de Entomología IVIA (Instituto Valenciano Investigaciones Agrarias) - CIB
(Centro Investigaciones Biológicas) del CSIC. IVIA, Ctra. de Moncada a Nàquera km. 4,5;
46113 -Moncada, Valencia, Spain aurbaneja@ivia.es
The two-spotted spider mite, Tetranychus urticae Koch, is an important citrus pest in Spain
and elsewhere in the Mediterranean areas. In the last few years, T. urticae has become one of
the main pests in the clementines of the region of La Plana (Castellón), where more than 90%
of Spanish mandarin is produced. Panonychus citri (McGregor) is maintained under a
satisfactory control in all Spanish citrus areas by the phytoseid Euseius stipulatus Athias-
Henriot. In contrast, predatory mites do not control T. urticae. As a first step to explain the
inefficient biological control of T. urticae, a survey was carried out to compare the natural
enemies related to the abundance of each mite in citrus orchards in the “Comunidad
Valenciana”. A similar number of phytoseids per infested leaf was associated to both spider
mites species, though the species composition of phytoseids was different. Thus, Euseius
stipulatus was the most abundant on citrus groves infested with P. citri. In contrast, the
abundance of Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus (McGregor)
was higher on those infested with T. urticae. Differences on the abundance of other natural
enemies were also found, being Stethorus punctillum Weise and Contwenzia psociformis
Curt. the two prevalent species for both spider mites.