Insects enemies of the black scale, Saissetia oleae (bernad) on olive in Argentina

MURÚA, M. G.; FIDALGO, P.

Foz de Iguazú, Brasil

Congreso; XXI Congreso Internacional de Entomología; 2000

Saissetia oleae is a poliphagous species widely distributed over the tropical and subtropical regions of the world and is a serious pest in citrus and olive trees. In Mendoza and San Juan provinces (Argentina) it is the most important pest together with Pollinia pollinii, while in La Rioja and Catamarca it is found with Parlatoria oleae. The parasitoids Metaphycus helvolus, M. Lounsburyi and Coccophagus caridei, were introduced in Mendoza in 1969 from Chile for it control. These species were recovered in very small percentages, and their establishment and were not evaluated. According to the bibliography, five species of parasitoids of S. oleae were registered in Argentina, but a study of the enemies of the pest was never carried out in olive. Collections of insects enemies of black scale on olive groves at La Rioja were carried out during January and October of 1999 and February of 2000. The materials colleted were observed in the laboratory and the insets obtained were identified and deposited as “vouecher specimenes” at the FML,s collections.  Four species of parasitoids and two species of predators were registered. The parasitods were: Lecaniobius utilis, Coccophagus caridei, Metaphycus stanleyi and Brasema sp.. The last two species were not found previously in Argentina. The predators obtained were the coccinellid Azya bioculata and Chrysopidae sp.. The parasites associated with black scale is not enaugh able to prevent the pest status attained in Argentina by S. oleae. The introduction of additional enemies is therefore highly recommended. In the world the encyrtid Diversinervus elegans (Silvestri) is the most important and efficient parasitoid in the control of S. oleae, but is not present in Argentina.  The introduction of this species would be very important to obtain a complete biological control of this pest in olive. Index word: natural enemies, Saissetia oleae, olive, Diversinervus elegans.