Journal of Chemical Ecology

, Volume 35, Issue 4, pp 476–478

Changes in Nutritional Value of Cyanogenic Trifolium repens Grown at Elevated Atmospheric CO2

  • Roslyn M. Gleadow
  • Everard J. Edwards
  • John R. Evans
Rapid Communication


Global food security in a changing climate depends on both the nutritive value of staple crops as well as their yields. Here, we examined the direct effect of atmospheric carbon dioxide on the toxicity of the important pasture crop, Trifolium repens L. (clover). Shoots of T. repens contain cyanogenic glycosides that break down to release toxic hydrogen cyanide when damaged. The ability of animals to tolerate cyanogenic compounds is dependent, in part, on their overall protein intake. We grew T. repens communities at ambient and approximately twice-ambient CO2 in a controlled environment greenhouse experiment. We found that the ratio of total cyanogenic glycosides to total protein ratio was nearly two times higher in leaves of T. repens grown at elevated CO2. This study highlights the importance of assessing the nutritive value of this and other plants in response to rising CO2 so that steps can be taken to address any adverse consequences for herbivores.


Clover Cyanide Linamarin Climate change Secondary metabolism Defense Cyanogenic glycoside 


  1. Ainsworth, E. A., and Long, S. P. 2005. What have we learned from 15 years of free-air CO2 enrichment (FACE)? A meta-analytic review of the responses of photosynthesis, canopy properties and plant production to rising CO2. New Phytologist 165:351–372.PubMedCrossRefGoogle Scholar
  2. Bazin, A., Goverde, M., Erhardt, A., and Shykoff, J. A. 2002. Influence of atmospheric carbon dioxide enrichment on induced response and growth compensation after herbivore damage in Lotus corniculatus. Ecological Entomology 27:271–278.CrossRefGoogle Scholar
  3. Edwards, E. J., Mccaffery, S., and Evans, J. R. 2006. Phosphorus availability and elevated CO2 affect biological nitrogen fixation and nutrient fluxes in a clover-dominated sward. New Phytologist 169:157–167.PubMedCrossRefGoogle Scholar
  4. Frehner, M., Luscher, A., Hebeisen, T., Zanetti, S., Schubiger, F., and Scalet, M. 1997. Effects of elevated partial pressure of carbon dioxide and season of the year on forage quality and cyanide concentration of Trifolium repens L. from a FACE experiment. Acta Oecologica 18:297–304.CrossRefGoogle Scholar
  5. Gleadow, R. M., and Woodrow, I. E. 2002. Constraints on effectiveness of cyanogenic glycosides in herbivore defense. J. Chem. Ecol. 28:1297–1309.CrossRefGoogle Scholar
  6. Gleadow, R. M., Foley, W. J., and Woodrow, I. E. 1998. Enhanced CO2 alters the relationship between photosynthesis and defence in cyanogenic Eucalyptus cladocalyx F. Muell. Plant Cell & Environment 21:12–22.CrossRefGoogle Scholar
  7. Jones, D. A. 1998. Why are so many food plants cyanogenic. Phytochemistry 47:155–162.PubMedCrossRefGoogle Scholar
  8. Lincoln, D. A., Fajer, E. D., and Johnson, R. H. 1993. Plant–insect herbivore interactions in elevated CO2 environments. Trends in Ecol. Evolut. 8:64–68.CrossRefGoogle Scholar
  9. Taub, D. R., Miller, B., and Allen, H. 2008. Effects of elevated CO2 on the protein concentration of food crops: a meta-analysis. Global Change Biology 14:565–575.CrossRefGoogle Scholar
  10. Westley, J. 1988. Mammalian cyanide detoxification with sulphane sulphur, pp. 201–212, in D. Evered, and S. Harnett (eds.). Cyanide compounds in biologyWiley, Chichester.CrossRefGoogle Scholar
  11. Woodrow, I. E., Slocum, D., and Gleadow, R. M. 2002. Influence of water stress on cyanogenic capacity in Eucalyptus cladocalyx. Functional Plant Biol. 29:103–110.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Roslyn M. Gleadow
    • 1
  • Everard J. Edwards
    • 2
    • 3
  • John R. Evans
    • 2
  1. 1.School of Biological SciencesMonash UniversityMelbourneAustralia
  2. 2.Environmental Biology Group, Research School of Biological SciencesThe Australian National UniversityCanberraAustralia
  3. 3.CSIRO Plant IndustryMerbeinAustralia

Personalised recommendations