Quantification of Canavanine, 2-Aminoethanol, and Cyanamide in Aphis craccivora and its Host Plants, Robinia pseudoacacia and Vicia angustifolia: Effects of These Compounds on Larval Survivorship of Harmonia axyridis

• Published in: Journal of chemical ecology 2012-12, Vol.38 (12), p.1552-1560
• Main Authors: Kamo, Tsunashi, Tokuoka, Yoshinori, Miyazaki, Masahisa
• Format: Article
• Language: English
• Subjects: Agriculture; Amino Acids - chemistry; Animals; Aphididae; Aphids - chemistry; Aphis craccivora; Bioassays; Biochemistry; Biological Microscopy; Biomedical and Life Sciences; Canavanine - analysis; Canavanine - toxicity; Chemical ecology; Chromatography, High Pressure Liquid; Coleoptera - growth & development; Coleoptera - physiology; Cyanamide - analysis; Cyanamide - toxicity; Diet - veterinary; Ecology; Entomology; Ethanolamine - analysis; Ethanolamine - toxicity; Female; Gas Chromatography-Mass Spectrometry; Harmonia axyridis; Host plants; Insects; Larva - drug effects; Larva - physiology; Larvae; Life Sciences; Parasites; Plant biology; Plant extracts; Robinia - chemistry; Robinia pseudoacacia; Survival Rate; Toxicity; Vicia - chemistry; Vicia angustifolia
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1007/s10886-012-0220-9

The cowpea aphid Aphis craccivora that infests the black locust Robinia pseudoacacia shows toxicity to its predator, the multicolored Asian ladybird beetle, Harmonia axyridis . In contrast, the same aphid species that infests the common vetch, Vicia angustifolia , is suitable prey for H. axyridis larvae. Previously, it was reported that the toxicity of A. craccivora infesting R. pseudoacacia was due to canavanine and 2-aminoethanol, but there was some doubt about the toxicity of these compounds and their concentrations in the aphids. In the present study, we determined the concentrations of cyanamide, canavanine, and 2-aminoethanol in A. craccivora infesting the two host plants. In the extracts of A. craccivora that infested either of the host plants, canavanine was undetectable, and 2-aminoethanol was detected at the concentration of 3.0–4.0 μg/g fresh weight. Cyanamide was detected in the extract of A. craccivora that infested R. pseudoacacia (7.7 μg/g fresh weight) but not in that infesting V. angustifolia . The toxicity of canavanine, 2-aminoethanol, and cyanamide was evaluated against H. axyridis larvae in a bioassay by using an artificial diet containing these compounds at various concentrations. Cyanamide exhibited 10–100 times stronger toxicity than canavanine and 2-aminoethanol. These results indicate that the toxicity is at least partly due to cyanamide, which is present in the toxic A. craccivora that infests R. pseudoacacia but absent from the non-toxic A. craccivora that infests V. angustifolia .