Plant organic nitrogen nutrition: costs, benefits, and carbon use efficiency

Sammanfattning

Differences in soil mobility and assimilation costs between organic and inorganic nitrogen (N) compounds would hypothetically induce plant phenotypic plasticity to optimize acquisition of, and performance on, the different N forms. Here we evaluated this hypothesis experimentally and theoretically. We grew Arabidopsis in split-root setups combined with stable isotope labelling to study uptake and distribution of carbon (C) and N from l-glutamine (l-gln) and NO3- and assessed the effect of the N source on biomass partitioning and carbon use efficiency (CUE). Analyses of stable isotopes showed that 40-48% of C acquired from l-gln resided in plants, contributing 7-8% to total C of both shoots and roots. Plants grown on l-gln exhibited increased root mass fraction and root hair length and a significantly lower N uptake rate per unit root biomass but displayed significantly enhanced CUE. Our data suggests that organic N nutrition is linked to a particular phenotype with extensive growth of roots and root hairs that optimizes for uptake of less mobile N forms. Increased CUE and lower N uptake per unit root growth may be key facets linked to the organic N phenotype.

Nyckelord

amino acids; Arabidopsis thaliana; carbon use efficiency; glutamine; organic nitrogen; root hair

Publicerad i

New Phytologist
2025, volym: 245, nummer: 3, sidor: 1018-1028

SLU författare

• Tunnermann, Laura

  • Institutionen för skoglig genetik och växtfysiologi, Sveriges lantbruksuniversitet
    

• Aguetoni Cambui, Camila

  • Institutionen för skoglig genetik och växtfysiologi, Sveriges lantbruksuniversitet
    

• Franklin, Oskar

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    
  • International Institute for Applied Systems Analysis (IIASA)

• Merkel, Patrizia

  • Institutionen för skoglig genetik och växtfysiologi, Sveriges lantbruksuniversitet
    

• Näsholm, Torgny

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    
  • Institutionen för skoglig genetik och växtfysiologi, Sveriges lantbruksuniversitet
    

• Gratz, Regina

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Botanik

Publikationens identifierare

• DOI: https://doi.org/10.1111/nph.20285

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/139409