Abstract

Effects of Sinorhizobium strain and P nutrition on N-2-dependent growth, nitrogenase activity and proton efflux by nodulated roots were investigated in the model legume Medicago truncatula cultivar Jemalong grown in hydroaeroponic culture in symbioses with Sinorhizobium meliloti strains 102F51 and 2011. Sinorhizobium strain had strong effects on nitrogenase activity and N-2-dependent growth, with S. meliloti 102F51 being the more efficient strain. Apparent and total nitrogenase activities, measured by hydrogen evolution in air and argon, respectively, were drastically reduced in plants supplied with 5 mu mol P plant(-1) week(-1) as compared with 15 mu mol P plant(-1) week(-1). There was a net proton efflux as soon as 2 weeks after inoculation and, in contrast to the effect of P nutrition on nitrogenase activity, P deficiency increased total and specific proton effluxes, irrespective of Sinorhizobium strain. (C) 2011 Elsevier Masson SAS. All rights reserved.

Keywords

Model legume; Nitrogen fixation; P deficiency; Sinorhizobium meliloti; Symbiosis

Published in

Plant Physiology and Biochemistry
2011, Volume: 49, number: 4, pages: 458-460
Publisher: ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER

SLU Authors

• Carlsson, Georg

  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences
    
  • National Institute of Agricultural Research (INRA)

UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1016/j.plaphy.2011.01.022

Permanent link to this page (URI)

https://res.slu.se/id/publ/58880