Aspectos biologicos e seletividade de alguns acaricidas a Ceraeochrysa cubana (Hagen, 1861) (Neuroptera Chrysopidae) em laboratorio

Abstract

The objective of this work was to study the biology of larvas and adults of Ceraeochrysa cubana (Hagen, 1861) (Neuroptera: Chrysopidae) fed with different diets, and to evaluate the selectivity of some acaricides to eggs, larvae and adults. The experiments were carried out in the Insect Biology Laboratory at "Escola Superior de Agricultura de Lavras", Minas Gerais State, Brazil. The temperature was maintained at 25 ± 2°C; the relative humidity was 70 ± 10% and the photoperiod was 12:12 hours. Larvae fed with eggs of Anagasta kuehniella (Zeller) + aphids Toxoptera citricidus Kirk. developed best in comparison with other diets tested, having produced greater number of adults in relation to those fed only with eggs of Anagasta kuehniella (Zeller). Larvae fed with the aphid Toxopterá citricidus Kirk. generally died before they reached the pre-pupal stage. Biological aspects of adults, which were obtained from larvae fed with eggs.of Anagasta kuehniella (Zeller) + aphids Toxoptera citricidus Kirk. were examined, with the insects being fed on three different diets: yeast + honey bee, yeast + frutose and yeast + sacarose. The greatest reproduction Rate was observed for insects fed with yeast +honey bee, mainly until 30 to 40 days after the beginning of the oviposition period. The addition of an aminoacids solution (AminosterilR) on eggs of Anagasta kuehniella (Zeller) increased the production of adults, though it reduced in the production of eggs during the first month of oviposition. The results of selectivity obtained, although preliminary, demonstrated that the acaricides abamectin, bromopropilato, sulphur, fenpropathrin and tetradifon, did not show ovicidal activity, and were selective to larvae and adults, except fenpropathrin, which was highly toxic to adults, either in the laboratory or in the greenhouse.