Comparative effect of inorganic N on plant growth and N-2 fixation of ten legume crops: towards a better understanding of the differential response among species

Abstract

AimsA better understanding of how plant growth, N nutrition and symbiotic nitrogen fixation (SNF) are influenced by soil inorganic N availability, for a wide range of legume species, is crucial to optimise legume productivity, N-2 fixation, while limiting environmental risks such as N leaching.MethodsA comparative analysis was performed for ten legume crops, grown in a field experiment and supplied with four N fertiliser rates. Dry matter, N concentration and SNF were measured. In parallel, root elongation rates were studied in a greenhouse experiment.ResultsFor most species, N fertilisation had little effect on plant growth and N accumulation. SNF was reduced by soil inorganic N available at sowing but with large differences in the magnitude of the response among species. The response varied according to plant N requirements for growth and plant ability to retrieve inorganic N. Accordingly, root lateral expansion rate measured in RhizoTubes was highly correlated with plant ability to retrieve inorganic N measured in the field experiment.ConclusionCombining SNF response to soil inorganic N, shoot N and plant ability to retrieve inorganic N, allowed a robust evaluation of differential response to soil inorganic N among a wide range of legume species.

Keywords

Grain legumes; Plant growth; Nitrogen nutrition; Symbiotic N-2 fixation; Nitrogen use efficiency; Root soil exploration

Published in

Plant and Soil
2018, Volume: 432, number: 1-2, pages: 207-227
Publisher: SPRINGER

SLU Authors

• Guinet, Maé

  • Department of Biosystems and Technology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1007/s11104-018-3788-1

Permanent link to this page (URI)

https://res.slu.se/id/publ/96989