Chrysoperla externa (Neuroptera: Chrysopidae) predate eggs of Duponchelia fovealis (Lepidoptera: Crambidae), a pest of strawberry

Abstract

Duponchelia fovealis is an important pest in strawberry crops. In search of an alternative biological control method, the objective of this study was to assess the effects of a diet composed of Ephestia kuehniella or D. fovealis eggs offered to Chrysoperla externa larvae on their subsequent development and survival under controlled conditions. Biological and reproductive parameters of C. externa were assessed. Additionally, the daily predation of D. fovealis eggs by C. externa was analyzed. Finally, a fertility life table was constructed. The egg-to-pupa development time differed significantly between diets. The weights of firstand second-generation male C. externa pupae were significantly higher when fed on D. fovealis eggs. Males tended to live longer on a diet based on D. fovealis eggs, but females presented no significant differences between diets. The oviposition period tended to be longer for C. externa fed on D. fovealis eggs. The time between generations and the net reproductive rate were greater for C. externa fed on D. fovealis eggs. The results showed that D. fovealis eggs are a suitable diet for the development of C. externa. This information is important for developing protocols for the use of C. externa as a biocontrol agent against this pest.