Biological parameters of adult of Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) fed on Asteraceae pollen under laboratory conditions

Abstract

The objective of this study was to evaluate the biological parameters and the preference of Artemisia tridentata Nutt (Asteraceae) industrial pollen grains and beer yeast by Ch. externa adults for a more suitable diet for laboratory rearing. To conduct the experiment, 105 adults of newly emerged Ch. externa were used. They were placed in PVC cages (10.0 cm high x 10.0 cm in diameter), closed with PVC plastic film, each cage contained two females and one male (2: 1), and each cage was placed on a diet, being they are: Artemisia pollen (A. tridentata), artemisia + honey pollen (mixed), beer yeast, beer yeast + honey (mixed), water, honey, artemisia pollen + honey (separated). The diets 2 (artemisia pollen + mixed honey), 3 (brewer's yeast) and 4 (brewer's yeast + mixed honey) were shown to be statistically good diets at 5% confidence, according to the results analyzed for the parameters fecundity, oviposition, oviposition, mean number of eggs/day and viability of eggs. As the other diets 1 (artemisia pollen), 5 (water), 6 (honey) and 7 (artemisia pollen + separated honey) did not obtain statistically results, because they had means zero or close to zero, so these treatments are not feasible for a rearing of Ch. externa in the laboratory.