Abstract
The variegated lady beetle, Hippodamia variegata (Goeze) predates different insect pests specially aphid species. The present study aimed to assess the effects of three various food sources on biological and demographic parameters of the predator under controlled laboratory conditions. The tested food sources were; Aphis fabae Scopoli as a natural prey, Ephestia kuehniella Zeller eggs and mixture of Ephestia eggs with corn pollens as a supplementary food. Results showed that both supplementary food diets achieved significant short pre-imaginal development times, long adult longevity and high fecundity of H. variegata than that fed on A. fabae. In contrast, egg hatching, incubation period of egg, survival rate, sex ratio, and postovipositional period were insignificantly affected by different food sources. Moreover, adding of corn pollens with Ephestia eggs achieved the highest fecundity, highest intrinsic rate of increase (r(m)) and highest net reproductive rate (R-0) of H. variegata. It could be concluded that the diet of Ephestia eggs plus corn pollens as a supplemental food improved the population growth of H. variegata, yielding higher reproductive rate therefore it could be improve the mass rearing of H. variegata under controlled laboratory conditions.