Plant Physiology Preview
Published on March 2, 2007; 10.1104/pp.107.097139
OPEN ACCESS ARTICLE
Received February 1, 2007
Accepted February 20, 2007
Nitrogen Fixation Control Under Drought Stress: Localised or Systemic?
Daniel Marino , Pierre Frendo , Ruben Ladrera , Ana Zabalza , Alain Puppo , Cesar Arrese-Igor , and Esther M. González *
Departamento de Ciencias del Medio Natural, Universidad Pública de Navarra, Campus Arrosadía, 31006 Pamplona, Spain; Interactions Plantes-Microorganismes et Santé Végétale, UMR CNRS 6192 - INRA 1064 - Université de Nice - Sophia Antipolis, 400, Route des Chappes, BP167 06903 Sophia Antipolis Cedex, France
* Corresponding author; email: esther.gonzalez{at}unavarra.es.
Legume-Rhizobium nitrogen fixation is dramatically affected under drought and other environmental constraints. However, it has yet to be established as to whether such regulation of nitrogen fixation is only exerted at the whole plant level (eg. by a systemic N feedback mechanism) or can also occur at a local nodule level. To address this question, nodulated pea plants were grown in a split-root-system, which allowed for half of the root system to be irrigated at field capacity, whilst the other half was water-deprived, thus provoking changes in the nodule water potential. Nitrogen fixation only declined in the water-deprived half-root system and this result was correlated with modifications in the activities of key nodules enzymes such as sucrose synthase and isocitrate dehydrogenase and in nodular malate content. Furthermore, the decline in nodule water potential resulted in a cell redox imbalance. The results also indicate that systemic N feedback signaling was not operating in these water stressed plants, since nitrogen fixation activity was maintained at control values in the watered half of the split-root plants. Thus, the use of a partially droughted split-root system provides evidence that nitrogen fixation activity under drought stress is mainly controlled at the local level rather than by a systemic N signal.
This article has been cited by other articles:
|
|
|
|
 
A. Rogers, E. A. Ainsworth, and A. D.B. Leakey
Will Elevated Carbon Dioxide Concentration Amplify the Benefits of Nitrogen Fixation in Legumes?
Plant Physiology,
November 1, 2009;
151(3):
1009 - 1016.
[Full Text]
[PDF]
|
|
|
|
|
|
|
P. D.R. van Heerden, G. Kiddle, T. K. Pellny, P. W. Mokwala, A. Jordaan, A. J. Strauss, M. de Beer, U. Schluter, K. J. Kunert, and C. H. Foyer
Regulation of Respiration and the Oxygen Diffusion Barrier in Soybean Protect Symbiotic Nitrogen Fixation from Chilling-Induced Inhibition and Shoots from Premature Senescence
Plant Physiology,
September 1, 2008;
148(1):
316 - 327.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Ruffel, S. Freixes, S. Balzergue, P. Tillard, C. Jeudy, M. L. Martin-Magniette, M. J. van der Merwe, K. Kakar, J. Gouzy, A. R. Fernie, et al.
Systemic Signaling of the Plant Nitrogen Status Triggers Specific Transcriptome Responses Depending on the Nitrogen Source in Medicago truncatula
Plant Physiology,
April 1, 2008;
146(4):
2020 - 2035.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. Ladrera, D. Marino, E. Larrainzar, E. M. Gonzalez, and C. Arrese-Igor
Reduced Carbon Availability to Bacteroids and Elevated Ureides in Nodules, But Not in Shoots, Are Involved in the Nitrogen Fixation Response to Early Drought in Soybean
Plant Physiology,
October 1, 2007;
145(2):
539 - 546.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
L. Naya, R. Ladrera, J. Ramos, E. M. Gonzalez, C. Arrese-Igor, F. R. Minchin, and M. Becana
The Response of Carbon Metabolism and Antioxidant Defenses of Alfalfa Nodules to Drought Stress and to the Subsequent Recovery of Plants
Plant Physiology,
June 1, 2007;
144(2):
1104 - 1114.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
