Predatory capacity of Adalia angulifera (Coleoptera: Coccinellidae) larvae on Myzocallis coryli (Hemiptera: Aphididae) in Chile
In La Araucanía, the filbert aphid Myzocallis coryli (Goeze) is a pest that can cause various types of damage to hazelnut (Corylus avellana L.) including reduction in nut size and nut emptiness. M. coryli can also leave hazel leaves susceptible to the fungus known as fumagina (Capnodium sp.), which causes decreased photosynthesis, particularly during the period when the tree is storing reserves for the following season. Knowledge about the natural enemies of M. coryli in Chile is in its early stages compared with other countries where the hazelnut crop is more extensive. Indeed, only 13 entomophagous predators have been recorded in La Araucanía thus far, including one Hemerobiidae, one Syrphidae, one Cecidomyiidae and ten Coccinellidae. Of this last family, Adalia is the best represented genus, with three species. In this study, the life cycle of the Adalia angulifera Mulsant (Coleoptera: Coccinellidae) has been ascertained. M. coryli as its food, and the ability of the larvae to prey on the same aphid is presented here. This study took place under semi-controlled laboratory and greenhouse conditions in the Region of the Araucanía, Chile. This study showed that the average predatory capacity of the A. angulifera larvae was 127.60± 33.21 specimens of M. coryli. For each larval instar (L), it was determined that the daily average prey was 6.8 ± 2.45 aphids for L I; 14.64 ± 5.77 aphids for L II; 42.72 ± 17.12 aphids for L III and 63.44 ± 26.21 aphids for L IV.