Suitability of seven aphid species as prey of Cheilomenes sexmaculata (Fabricius) (Coleoptera: Coccinellidae)

Abstract

The suitability of seven aphid species: Aphis gossypii, Aphis craccivora, Myzus persicae, Sitobion akebiae, Aulacorthum solani, Aulacorthum nipponicum and Acyrthosiphon pisum, as prey of Cheilomenes sexmaculata was evaluated from five biological and morphological characteristics (15L-9D, 18°C). All first instar larvae fed on A. nipponicum died in a few days. The mean developmental duration from hatching to adult eclosion was significantly shorter in A. craccivora (18.0 days) than in the four other aphid species (20.1-20.9 days) except M. persicae (18.7 days); the survival rate was not significantly different between these six species (70.3%-91.3%). Female pupae were significantly heavier in A. solani and M. persicae (18.4-18.5 mg) than in A. pisum (16.0 mg) or S. akebiae (15.2 mg). The mean preoviposition period was significantly shorter in A. craccivora, A. solani, A. akebiae, and M. persicae (7.3-8.0 days) than in A. gossypii (11.6 days). The mean number of eggs laid in the first 10 days after the start of oviposition was significantly more in A. craccivora (172) than in A. gossypii (99). From these results, A. craccivora and M. persicae are the best prey and A. gossypii is the worst prey of C. sexmaculata, but the difference in suitability was not great. A prey list of C. sexmaculata is given.