Isoprene emission protects photosynthesis but reduces plant productivity during drought in transgenic tobacco (Nicotiana tabacum) plants

New Phytol. 2014 Jan;201(1):205-16. doi: 10.1111/nph.12477. Epub 2013 Sep 17.

Abstract

Isoprene protects the photosynthetic apparatus of isoprene-emitting plants from oxidative stress. The role of isoprene in the response of plants to drought is less clear. Water was withheld from transgenic isoprene-emitting and non-emitting tobacco (Nicotiana tabacum) plants, to examine: the response of isoprene emission to plant water deficit; a possible relationship between concentrations of the drought-induced phytohormone abscisic acid (ABA) and isoprene; and whether isoprene affected foliar reactive oxygen species (ROS) and lipid peroxidation levels. Isoprene emission did not affect whole-plant water use, foliar ABA concentration or leaf water potential under water deficit. Compared with well-watered controls, droughted non-emitting plants significantly increased ROS content (31-46%) and lipid peroxidation (30-47%), concomitant with decreased operating and maximum efficiencies of photosystem II photochemistry and lower leaf and whole-plant water use efficiency (WUE). Droughted isoprene-emitting plants showed no increase in ROS content or lipid peroxidation relative to well-watered controls, despite isoprene emission decreasing before leaf wilting. Although isoprene emission protected the photosynthetic apparatus and enhanced leaf and whole-plant WUE, non-emitting plants had 8-24% more biomass under drought, implying that isoprene emission incurred a yield penalty.

Keywords: Nicotiana tabacum (tobacco); abscisic acid (ABA); drought; hydrogen peroxide; isoprene; lipid peroxidation; oxidative stress; water use efficiency.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abscisic Acid / metabolism
  • Biomass*
  • Butadienes / metabolism*
  • Droughts*
  • Hemiterpenes / metabolism*
  • Lipid Peroxidation
  • Oxidative Stress*
  • Pentanes / metabolism*
  • Photosynthesis*
  • Photosystem II Protein Complex / metabolism
  • Plant Growth Regulators / metabolism
  • Plant Leaves / metabolism
  • Plant Leaves / physiology
  • Plants, Genetically Modified
  • Reactive Oxygen Species / metabolism
  • Tobacco / growth & development
  • Tobacco / metabolism
  • Tobacco / physiology*
  • Water / physiology*

Substances

  • Butadienes
  • Hemiterpenes
  • Pentanes
  • Photosystem II Protein Complex
  • Plant Growth Regulators
  • Reactive Oxygen Species
  • Water
  • isoprene
  • Abscisic Acid