Aspectos bioecológicos de Coccinellidae predadores de cochonilhas do algodoeiro

Abstract

Among the cotton pests stand out insects of the family Pseudococcidae, which suck sap from plants and may cause languish and lead to plant death. Due to the importance that the scales have for cotton crop, studies on the biological control agents adapted to local conditions are essential to expanding their use conservatively or even for their rearing and release. Among the natural enemies stand out Zagreus bimaculosus (Mulsant) (Coleoptera: Coccinellidae), a widely distributed species in South America associated with Diaspis echinocacti (Bouche) as well as with Dactylopius opuntiae (Cockerel), and Brumoides foudrasii (Mulsant) specie originated in West Africa which was recently recorded attacking the scale insect Ferrisia dasylirii (Cockerell) (Hemiptera: Pseudococcidae) on cotton in Pernambuco. Thus, this paper aims to describe bio-ecological aspects of these two coccinellids fed on F. dasylirii or on eggs of Anagasta kuehniella (Zeller) (Lepídoptera: Pyralidae). Although development period of Z. bimaculosus have not been influenced by the type of food, females that fed on F. dasylirii were longer-lived than those fed on eggs of A. kuehniella. F. dasylirii was considered adequate food for the rearing and multiplication of Z. bimaculosus. Eggs of A. kuehniella were considered an alternative food for rearing larvae of Z. bimaculosus, since it allowed the complete development of all imature phases, pupae and adult fertile, similar to those observed in the field. Regarding to B. foudrasii both foods allowed the survival and development of insects.