Mycorrhization protects Betula pubescens Ehr. from metal-induced oxidative stress increasing its tolerance to grow in an industrial polluted soil

J Hazard Mater. 2017 Aug 15:336:119-127. doi: 10.1016/j.jhazmat.2017.04.065. Epub 2017 Apr 27.

Abstract

In recent years, the use of woody plants in phytoremediation has gained popularity due to their high biomass production and their association with mycorrhizal fungi, which can improve their survival and development rates under stress conditions. In this study, mycorrhized and non-mycorrhized white birch plants (Betula pubescens Ehr.) were grown in control and a metal-polluted industrial soil. After 60days of culture, plant growth and metal accumulation, the content of photosynthetic pigments and oxidative-stress markers, as well as the enzymatic activities and gene expressions of antioxidant enzymes were measured. According to our results, mycorrhized birch plants grown in control soil showed an increased activity and gene expression of catalase and ascorbate peroxidase, along with hydrogen peroxide overproduction, which could support the importance of the reactive oxygen species as signaling molecules in the regulation of plant-fungus interactions. Additionally, in polluted soil mycorrhized plants had higher biomass but lower metal accumulation, probably because the symbiotic fungus acted as a barrier to the entrance of metals into the host plants. This behavior led to mitigation in the oxidative challenge, reduced hydrogen peroxide content and diminished activities of the antioxidant enzymes in comparison to non-mycorrhized plants.

Keywords: Gene expression; Heavy metals; Mycorrhization; Oxidative stress; Phytoremediation.

Publication types

  • Comparative Study

MeSH terms

  • Adaptation, Physiological
  • Ascorbate Peroxidases / genetics
  • Betula / drug effects*
  • Betula / growth & development
  • Betula / metabolism
  • Betula / microbiology
  • Biomarkers / metabolism
  • Catalase / genetics
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Plant
  • Hydrogen Peroxide / metabolism
  • Industrial Waste*
  • Metals / metabolism
  • Metals / toxicity*
  • Mycorrhizae / metabolism*
  • Oxidative Stress / drug effects*
  • Photosynthesis
  • Pigments, Biological / metabolism
  • Reactive Oxygen Species / metabolism
  • Signal Transduction
  • Soil Pollutants / metabolism
  • Soil Pollutants / toxicity*
  • Symbiosis

Substances

  • Biomarkers
  • Industrial Waste
  • Metals
  • Pigments, Biological
  • Reactive Oxygen Species
  • Soil Pollutants
  • Hydrogen Peroxide
  • Ascorbate Peroxidases
  • Catalase