Seletividade de acaricidas utilizados em cafeeiro para pré-pupas e adultos de Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae)

Abstract

The mites Oligonychus ilicis (McGregor, 1917) (Tetranychidae) and Brevipalpus phoenicis (Geijskes, 1939) (Tenuipalpidae) cause economic losses to coffee and they are usually controlled by means of chemical method. Among the natural enemies that regulate the population densities of arthropod pests, the green lacewings stand out, which must be preserved through the use of selective compounds. For this reason, the present study evaluated the effects of spirodiclofen (Envidor – 0.12 g a.i./L), fenpropathrin (Meothrin 300 – 0.15 and 0.30 g a.i./L), sulphur (Thiovit Sandoz – 4.0 and 8.0 g a.i./L) and abamectin (Vertimec 18 CE – 0.0067 and 0.0225 g a.i./L) on pre-pupae and adults of Chrysoperla externa (Hagen). The pesticides were applied directly on pre-pupae and adults of green lacewings, using a Potter’s tower. The pre-pupae were then transferred to glass tubes (2 x 8 cm) and the adults to PVC cages (10 x 10cm) and maintained in climatic chambers (25 ± 2o C, RH of 70 ± 10% and 12h photophase). The compounds were classified according to the total effect on the development of the predator, following recommendations of the IOBC. Spirodiclofen, fenpropathrin and abamectin were moderately harmful to C. externa, when applied on the pre-pupae, and sulphur was slightly harmful. When applied on adults, the acaricide fenpropathrin was harmful; spirodiclofen, abamectin and sulphur (8.0 g a.i./L) were moderately harmful, and sulphur (4.0 g a.i./L) was slightly harmful.