1H-NMR metabolomic profiling reveals a distinct metabolic recovery response in shoots and roots of temporarily drought-stressed sugar beets

PLoS One. 2018 May 8;13(5):e0196102. doi: 10.1371/journal.pone.0196102. eCollection 2018.

Abstract

Yield formation in regions with intermittent drought periods depends on the plant's ability to recover after cessation of the stress. The present work assessed differences in metabolic recovery of leaves and roots of drought-stressed sugar beets with high temporal resolution. Plants were subjected to drought for 13 days, and rewatered for 12 days. At one to two-day intervals, plant material was harvested for untargeted 1H-NMR metabolomic profiling, targeted analyses of hexose-phosphates, starch, amino acids, nitrate and proteins, and physiological measurements including relative water content, osmotic potential, electrolyte leakage and malondialdehyde concentrations. Drought triggered changes in primary metabolism, especially increases in amino acids in both organs, but leaves and roots responded with different dynamics to rewatering. After a transient normalization of most metabolites within 8 days, a second accumulation of amino acids in leaves might indicate a stress imprint beneficial in upcoming drought events. Repair mechanisms seemed important during initial recovery and occurred at the expense of growth for at least 12 days. These results indicate that organ specific metabolic recovery responses might be related to distinct functions and concomitant disparate stress levels in above- and belowground organs. With respect to metabolism, recovery was not simply a reversal of the stress responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Beta vulgaris / growth & development
  • Beta vulgaris / metabolism*
  • Droughts*
  • Metabolomics*
  • Plant Leaves / growth & development
  • Plant Leaves / metabolism*
  • Plant Proteins / metabolism*
  • Plant Roots / growth & development
  • Plant Roots / metabolism*
  • Proton Magnetic Resonance Spectroscopy / methods*
  • Stress, Physiological*

Substances

  • Plant Proteins

Grants and funding

RW received a salary from Bayer AG. The specific role of this author is articluated in the 'author contributions' section. We thank MetaboHUB (ANR-11-INBS-0010 project) and PHENOME (ANR-11-INBS-012) projects for financing. This study was also financially supported by the German Federal Ministry of Education and Research (BMBF 0315529) and the European Union for regional development (EFRE z1011bc001a) and is part of CROPSENSe.net, the competence network for phenotyping research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.