Effects of various components of artificial diets on survival, development and reproduction of Coccinella septempunctata L. (Coleoptera: Coccinellidae)

Abstract

ABSTRACT The ladybird beetle, Coccinella septempunctata, is an important predator of soft-bodied insects. To further optimise an artificial diet for rearing the ladybird beetle, we investigated the effects of juvenile hormone (JH), honey, shrimp, rape pollen, lard, and other factors on the biological characteristics of C. septempunctata. Survival and pupation rates of larvae were decreased when JH and lard were added to the artificial diet; however, the addition of lard increased egg hatching to 73.70%, which was significantly higher than the control diet (50.56%). Adding honeybee pupae to the artificial diet shortened the preoviposition period to 7.64 d, compared to 10.36 d in the control diet. Adding honey, shrimp, and honeybee pupae to the diet resulted in 465.12, 452.35, and 423.01 eggs laid, respectively, which was significantly higher than the control diet. The pupation and emergence rates of C. septempunctata larvae fed an artificial diet without JH were significantly higher than those fed an artificial diet with JH; thus, JH and lard should not be added to artificial diets during the larval stage. During the adult stage, adding rape pollen, shrimp, honey, lard, and honeybee pupae to the diet could improve the fecundity of C. septempunctata. These results will be helpful for optimising artificial diets for the mass production of C. septempunctata.