Climate extreme effects on the chemical composition of temperate grassland species under ambient and elevated CO2: a comparison of fructan and non-fructan accumulators

Hamada AbdElgawad; Darin Peshev; Gaurav Zinta; Wim Van den Ende; Ivan A Janssens; Han Asard

doi:10.1371/journal.pone.0092044

Climate extreme effects on the chemical composition of temperate grassland species under ambient and elevated CO2: a comparison of fructan and non-fructan accumulators

PLoS One. 2014 Mar 26;9(3):e92044. doi: 10.1371/journal.pone.0092044. eCollection 2014.

Authors

Hamada AbdElgawad¹, Darin Peshev², Gaurav Zinta³, Wim Van den Ende², Ivan A Janssens⁴, Han Asard¹

Affiliations

¹ Laboratory for Molecular Plant Physiology and Biotechnology, Department of Biology, University of Antwerp, Antwerp, Belgium.
² Laboratory of Molecular Plant Biology, KU Leuven, Leuven, Belgium.
³ Laboratory for Molecular Plant Physiology and Biotechnology, Department of Biology, University of Antwerp, Antwerp, Belgium; Research Group of Plant and Vegetation Ecology, Department of Biology, University of Antwerp (Campus Drie Eiken), Wilrijk, Belgium.
⁴ Research Group of Plant and Vegetation Ecology, Department of Biology, University of Antwerp (Campus Drie Eiken), Wilrijk, Belgium.

Abstract

Elevated CO2 concentrations and extreme climate events, are two increasing components of the ongoing global climatic change factors, may alter plant chemical composition and thereby their economic and ecological characteristics, e.g. nutritional quality and decomposition rates. To investigate the impact of climate extremes on tissue quality, four temperate grassland species: the fructan accumulating grasses Lolium perenne, Poa pratensis, and the nitrogen (N) fixing legumes Medicago lupulina and Lotus corniculatus were subjected to water deficit at elevated temperature (+3°C), under ambient CO2 (392 ppm) and elevated CO2 (620 ppm). As a general observation, the effects of the climate extreme were larger and more ubiquitous in combination with elevated CO2. The imposed climate extreme increased non-structural carbohydrate and phenolics in all species, whereas it increased lignin in legumes and decreased tannins in grasses. However, there was no significant effect of climate extreme on structural carbohydrates, proteins, lipids and mineral contents and stoichiometric ratios. In combination with elevated CO2, climate extreme elicited larger increases in fructan and sucrose content in the grasses without affecting the total carbohydrate content, while it significantly increased total carbohydrates in legumes. The accumulation of carbohydrates in legumes was accompanied by higher activity of sucrose phosphate synthase, sucrose synthase and ADP-Glc pyrophosphorylase. In the legumes, elevated CO2 in combination with climate extreme reduced protein, phosphorus (P) and magnesium (Mg) contents and the total element:N ratio and it increased phenol, lignin, tannin, carbon (C), nitrogen (N) contents and C:N, C:P and N:P ratios. On the other hand, the tissue composition of the fructan accumulating grasses was not affected at this level, in line with recent views that fructans contribute to cellular homeostasis under stress. It is speculated that quality losses will be less prominent in grasses (fructan accumulators) than legumes under climate extreme and its combination with elevated CO2 conditions.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Carbohydrate Metabolism / drug effects
Carbon Dioxide / pharmacology*
Climate Change*
Fructans / metabolism*
Grassland*
Species Specificity
Trace Elements / analysis

Substances

Fructans
Trace Elements
Carbon Dioxide

Grants and funding

This research was funded by the University of Antwerp concerted research project “Changes in the stress sensitivity of plants and ecosystems under climate change conditions” (GOA-BOF-UA-2007). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.