3 Energetics of Nitrogen Acquisition

Annual Plant Reviews book series, Volume 42: Nitrogen Metabolism in Plants in the Post-genomic Era
Arnold J. Bloom

Arnold J. Bloom

Department of Plant Sciences, University of California at Davis, Davis, CA, 95161 USA

Search for more papers by this author
First published: 19 April 2018
This article was originally published in 2011 in Nitrogen Metabolism in Plants in the Post-genomic Era, Volume 42 (ISBN ) of the Annual Plant Reviews book series, this volume edited by . The article was republished in Annual Plant Reviews online in April 2018.

Abstract

Plants employ a variety of mechanisms to acquire nitrogen from their environment ranging from carnivory to symbiotic relationships with bacteria. Most plants, however, obtain the majority of their nitrogen as nitrate and ammonium that their roots absorb from soils. To compete successfully against soil micro-organisms for soil nitrate or ammonium, plants adjust their growth, development and physiology to exploit the distinct properties of each ion.

Nitrate is more mobile than ammonium through most soils. Plants can store high concentrations of nitrate, but not ammonium, within their tissues. Yet, assimilation of nitrate into amino acids is far more energy-intensive than that of ammonium. Plants offset some of the energy costs of nitrate assimilation by coupling it with photorespiration. Rising carbon dioxide levels in the atmosphere inhibits photorespiration and, thereby, nitrate assimilation. Therefore, ammonium and nitrate management will become even more critical in the future.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.