Long-term exposure to elevated carbon dioxide (CO₂) may select for different plant phenotypes with consequences for microbial associations and functions. We collected seeds from two grasses that had grown in a Free Air Carbon Dioxide Enrichment (FACE) experiment for 5 and 11 years, and grew them in a common garden to assess how elevated CO₂ affected the rate of nitrification in rhizosphere soil. The comparison was made in a 'common-garden' so that differences could be ascribed to inherent changes in the plant populations. We found that seed of both species from the ambient populations produced plants that had similar rates of nitrification; however, seed from the elevated CO₂ population produced ryegrass plants with a significantly greater nitrification rate and browntop plants with a significantly lower rate than the ambient population. These differences were not related to changes in root mass so represent a fundamental shift in plant/microbe interactions under elevated CO₂.

Item Type:	Refereed Article
Keywords:	soil nitrification, elevated CO2, soil microbes, nitrogen availability
Research Division:	Biological Sciences
Research Group:	Ecology
Research Field:	Terrestrial Ecology
Objective Division:	Expanding Knowledge
Objective Group:	Expanding Knowledge
Objective Field:	Expanding Knowledge in the Environmental Sciences
Author:	Hovenden, M (Associate Professor Mark Hovenden)
Author:	Osanai, Y (Ms Yui Osanai)
ID Code:	85915
Year Published:	2013
Funding Support:	Australian Research Council (DP0984779)
Web of Science® Times Cited:	3
Deposited By:	Plant Science
Deposited On:	2013-08-14
Last Modified:	2017-11-03
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