Too much is bad--an appraisal of phytotoxicity of elevated plant-beneficial heavy metal ions

Environ Sci Pollut Res Int. 2015 Mar;22(5):3361-82. doi: 10.1007/s11356-014-3849-9. Epub 2014 Nov 20.

Abstract

Heavy metal ions such as cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), and zinc (Zn) are considered essential/beneficial for optimal plant growth, development, and productivity. However, these ions readily impact functions of many enzymes and proteins, halt metabolism, and exhibit phytotoxicity at supra-optimum supply. Nevertheless, the concentrations of these heavy metal ions are increasing in agricultural soils worldwide via both natural and anthropogenic sources that need immediate attention. Considering recent breakthroughs on Co, Cu, Fe, Mn, Mo, Ni, and Zn in soil-plant system, the present paper: (a) overviews the status in soils and their uptake, transport, and significance in plants; (b) critically discusses their elevated level-mediated toxicity to both plant growth/development and cell/genome; (c) briefly cross talks on the significance of potential interactions between previous plant-beneficial heavy metal ions in plants; and (d) highlights so far unexplored aspects in the current context.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Heavy Metal Poisoning*
  • Metals, Heavy / analysis
  • Plant Development / drug effects
  • Plants / drug effects*
  • Plants / metabolism
  • Poisoning*
  • Soil Pollutants / analysis
  • Soil Pollutants / toxicity*

Substances

  • Metals, Heavy
  • Soil Pollutants