Predator consumption, development, and fecundity were assessed for the predatorprey interaction between Coleomegilla maculata (De Geer) and Leptinotarsa decemlineata (Say) feeding on Cry3A-transgenic or normal (nontransgenic) foliage of potato. The influence of bee pollen, a food supplement, on development and fecundity was also assessed. Neonates of L. decemlineata feeding on transgenic foliage lost considerable body weight, in comparison to those feeding on normal foliage. After differences in prey weight were considered, no significant difference was found between the proportion of transgenic-fed or normal-fed neonates consumed by C. maculata. There was no significant difference between the proportion of C. maculata developing into pupae and adults when reared on transgenic-fed or normal-fed prey; nor did the live weight of teneral adults differ. The proportion of C. maculata reaching maturation when reared on transgenic-fed prey with pollen was greater than those reared on pollen alone, which suggests the suitability of a diet containing animal and plant material. Predator fecundity, measured as egg deposition per day, was not significantly different between mated females provided with transgenic-fed prey with pollen or normal-fed prey with pollen. These data suggest that Cry3A-intoxicated L. decemlineata can be eaten by C. maculata without any observable adverse effects on their survival or predation potential.

As part of my research on the mass production and augmentative release of ladybirds, I reviewed the primary research literature to test the prediction that ladybirds are effective aphid predators in greenhouses. Aphid population reduction exceeded 50% in most studies and ladybird release rates usually did not correlate with aphid reduction. The ratio of aphid reduction/release rate was slightly less for larvae than adults in some studies, suggesting that larvae were less effective (than adults) in suppressing aphids. Some adult releases were inside cages, thereby limiting adult dispersion from plants. Overall, the ratio of aphid reduction/release rate was greatest for ladybird adults of the normal strain (several species combined), but least for adults of a flightless Harmonia axyridis strain. The combined action of ladybirds and hymenopteran parasitoids could have a net positive effect on aphid population suppression and, consequently, on host (crop) plants. However, ladybird encounters with aphid-tending or foraging ants must be reduced. Deploying ladybirds to help manage aphids in greenhouses and similar protective structures is encouraged.