Susceptibility and tolerance of rice crop to salt threat: Physiological and metabolic inspections

PLoS One. 2018 Feb 28;13(2):e0192732. doi: 10.1371/journal.pone.0192732. eCollection 2018.

Abstract

Salinity threat is estimated to reduce global rice production by 50%. Comprehensive analysis of the physiological and metabolite changes in rice plants from salinity stress (i.e. tolerant versus susceptible plants) is important to combat higher salinity conditions. In this study, we screened a total of 92 genotypes and selected the most salinity tolerant line (SS1-14) and most susceptible line (SS2-18) to conduct comparative physiological and metabolome inspections. We demonstrated that the tolerant line managed to maintain their water and chlorophyll content with lower incidence of sodium ion accumulation. We also examined the antioxidant activities of these lines: production of ascorbate peroxidase (APX) and catalase (CAT) were significantly higher in the sensitive line while superoxide dismutase (SOD) was higher in the tolerant line. Partial least squares discriminant analysis (PLS-DA) score plots show significantly different response for both lines after the exposure to salinity stress. In the tolerant line, there was an upregulation of non-polar metabolites and production of sucrose, GABA and acetic acid, suggesting an important role in salinity adaptation. In contrast, glutamine and putrescine were noticeably high in the susceptible rice. Coordination of different strategies in tolerant and susceptible lines show that they responded differently after exposure to salt stress. These findings can assist crop development in terms of developing tolerance mechanisms for rice crops.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbate Peroxidases / metabolism
  • Catalase / metabolism
  • Crops, Agricultural / enzymology
  • Crops, Agricultural / genetics
  • Crops, Agricultural / physiology*
  • Magnetic Resonance Spectroscopy
  • Metabolome
  • Oryza / enzymology
  • Oryza / genetics
  • Oryza / physiology*
  • Oxidative Stress*
  • Salinity*
  • Salt Tolerance*
  • Sodium Chloride*
  • Superoxide Dismutase / metabolism

Substances

  • Sodium Chloride
  • Ascorbate Peroxidases
  • Catalase
  • Superoxide Dismutase

Grants and funding

The works were supported by Fundamental Research Grant Scheme (FRGS) (VOT 59342) - project leader Nyuk Ling Ma; and Long Term Research Grant Scheme (LRGS) under Abotic breeding of Rice Varieties - Project leader Mohd Razi Ismail.