Effect of Six Diets on Development and Fecundity ofHarmonia axyridis(Pallas) (Coleoptera: Coccinellidae)

Abstract

Effect of six different diets on the development and oviposition of Harmonia axyridis was studied. The developmental time of larvae fed on different diets ranged from 9.3 to 16.2 days, and the artificial diet-grown larvae showed a significantly longer developmental time than those fed on Sitotroga cerealella eggs or Chaitophorus populeti. They also showed a lower adult emergence rate, which were only 3.6% to 16.0 %, while it was 90.0 % on C. populeti and 72.1 % on S. cerealella eggs. The C. populeti was the best diet in terms of reproduction, because of the shorter pre-oviposition period and higher fecundity of its females compared to the females on artificial diets and S. cerealella eggs. In order to evaluate the potential of S. cerealella eggs for rearing H. axyridis as a supplementary prey, its effect on the fecundity of H. axyridis was tested. The results revealed that for adults fed on C. populeti, their larval food source had no significant effect on duration of pre-oviposition period (8.6 and 7.5 d...