Does Salicylic Acid (SA) Improve Tolerance to Salt Stress in Plants? A Study of SA Effects On Tomato Plant Growth, Water Dynamics, Photosynthesis, and Biochemical Parameters

OMICS. 2016 Mar;20(3):180-90. doi: 10.1089/omi.2015.0161. Epub 2016 Feb 24.

Abstract

Environmental stresses such as salinity directly impact crop growth, and by extension, world food supply and societal prosperity. It is estimated that over 800 million hectares of land throughout the world are salt-affected. In arid and semi-arid regions, salt concentration can be close to that in the seawater. Hence, there are intensive efforts to improve plant tolerance to salinity and other environmental stressors. Salicylic acid (SA) is an important signal molecule for modulating plant responses to stress. In the present study, we examined, on multiple plant growth related endpoints, whether SA applied through the rooting medium could mitigate the adverse effects of salinity on tomato (Solanum lycopersicum) cv. Marmande. The latter is a hitherto understudied tomato plant from the above perspective; it is a classic variety that produces the large ribbed tomatoes in the Mediterranean and consumed worldwide. We found salt stress negatively affected the growth of cv. Marmande tomato plants. However, the SA-treated plants had greater shoot and root dry mass, leaf area compared to untreated plants when exposed to salt stress. Application of SA restores photosynthetic rates and photosynthetic pigment levels under salt (NaCl) exposure. Leaf water, osmotic potential, stomatal conductance transpiration rate, and biochemical parameters were also ameliorated in SA-treated plants under saline stress conditions. Overall, these data illustrate that SA increases cv. Marmande tomato growth by improving photosynthesis, regulation and balance of osmotic potential, induction of compatible osmolyte metabolism, and alleviating membrane damage. We suggest salicylic acid might be considered as a potential growth regulator to improve tomato plant salinity stress resistance, in the current era of global climate change.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / drug effects*
  • Photosynthesis / drug effects
  • Plant Leaves / drug effects
  • Plant Leaves / growth & development
  • Plant Leaves / metabolism
  • Plant Roots / drug effects
  • Plant Roots / growth & development
  • Plant Roots / metabolism
  • Salicylic Acid / pharmacology*
  • Salinity
  • Salt Tolerance / drug effects*
  • Salt Tolerance / physiology
  • Sodium Chloride / pharmacology
  • Solanum lycopersicum / drug effects*
  • Solanum lycopersicum / growth & development
  • Solanum lycopersicum / metabolism
  • Stress, Physiological
  • Water / metabolism*

Substances

  • Water
  • Sodium Chloride
  • Salicylic Acid