Ecological Research

, Volume 22, Issue 4, pp 671–677

Carbon–nitrogen stoichiometry in the tritrophic food chain willow, leaf beetle, and predatory ladybird beetle

Authors

    • Center for Ecological ResearchKyoto University
  • Takayuki Ohgushi
    • Center for Ecological ResearchKyoto University
Original Article

DOI: 10.1007/s11284-006-0314-3

Cite this article as:
Kagata, H. & Ohgushi, T. Ecol Res (2007) 22: 671. doi:10.1007/s11284-006-0314-3

Abstract

Although plant quality can indirectly increase the performance of the third trophic level by bottom-up cascading effects, the mechanisms of this indirect effect are still unclear. In this study the carbon–nitrogen stoichiometry in a tri-trophic system consisting of the willow, a leaf beetle, and a predatory ladybird beetle were examined to determine the mechanisms of the bottom-up cascading effect. The bottom-up cascade is initiated by increasing leaf nitrogen, because of artificial cutting of willow trees. The relative growth rate (RGR) of the leaf beetle increased when fed on cut willow leaves, because of the high leaf nitrogen in the cut willows. Ladybird beetle RGR also increased when fed on leaf beetles fed on cut willow leaves. The increased RGR of the ladybirds cannot be explained by the quality of the prey, however, because leaf beetle nitrogen was not affected by host plant quality. Thus, the carbon–nitrogen stoichiometry could not be a mechanism of the bottom-up cascade through multiple trophic levels.

Keywords

Bottom-up cascade C:N ratio Ecological stoichiometry Terrestrial food chain Tri-trophic interaction

Copyright information

© The Ecological Society of Japan 2006