Comparison of prey consumption by Dicyphus tamaninii reared conventionally, and on a meat-based diet

Abstract

The zoophytophagous predator Dicyphus tamaninii Wagner (Heteroptera: Miridae) has been successfully reared for more than five generations on a meat-based diet, and in the absence of a plant as a substrate for oviposition and feeding. We compared the predation efficiency of D. tamaninii produced on this diet with those reared conventionally on Ephestia kuehniella eggs (Zeller) (Lepidoptera: Pyralidae) and tobacco plants. Their performances were evaluated on two prey, the greenhouse whitefly Trialeurodes vaporariorum West- wood (Homoptera: Aleyrodidae) and the cotton aphid Aphis gossypii Glover (Homoptera: Aphididae). Their tendency to cannibalistic behaviour was also evaluated. Nymphs of D. tamaninii produced on the meat diet consumed a similar number of greenhouse whitefly pupae after 24 and 48 hours to nymphs reared by the conventional method. Diet-reared females consumed significantly more whitefly pupae after 24 and 48 hours than control females. When the cotton aphid was offered, diet-reared D. tamaninii nymphs and females consumed similar numbers of prey to control D. tamaninii. There was no significant increase in cannibalistic behaviour of diet-reared D. tamaninii after 3 and 5 days of interaction. These results show that, after five generations, the predation efficiency and the tendency to cannibalism of meat-reared D. tamaninii is similar to that of conventionally-reared individuals.