title: Effects of elevated carbon dioxide on stomatal characteristics and carbon isotope ratio of Arabidopsis thaliana ecotypes originating from an altitudinal gradient.
abstract: Stomatal functioning regulates the fluxes of CO2and water vapor between vegetation and atmosphere and thereby influences plant adaptation to their habitats. Stomatal traits are controlled by external environmental and internal cellular signaling. The objective of this study was to quantify the effects of CO2enrichment (CE) on stomatal density (SD)-related properties, guard cell length (GCL) and carbon isotope ratio (δ13C) of a range of Arabidopsis thaliana ecotypes originating from a wide altitudinal range [50-1260 m above sea level (asl)], and grown at 400 and 800 ppm [CO2], and thereby elucidate the possible adaptation and acclimation responses controlling stomatal traits and water use efficiency (WUE). There was a highly significant variation among ecotypes in the magnitude and direction of response of stomatal traits namely, SD and stomatal index (SI) and GCL, and δ13C to CE, which represented a short-term acclimation response. A majority of ecotypes showed increased SD and SI with CE with the response not depending on the altitude of origin. Significant ecotypic variation was shown in all stomatal traits and δ13C at each [CO2]. At 400 ppm, means of SD, SI and GCL for broad altitudinal ranges, i.e. low (<100 m), mid (100-400 m) and high (>400 m), increased with increasing altitude, which represented an adaptation response to decreased availability of CO2with altitude. δ13C was negatively correlated to SD and SI at 800 ppm but not at 400 ppm. Our results highlight the diversity in the response of key stomatal characters to CE and altitude within the germplasm of A. thaliana and the need to consider this diversity when using A. thaliana as a model plant.
authors: Department of Plant Sciences, Faculty of Science, University of Colombo, Colombo, Sri Lanka.
authors: H Iroja U
authors: HI
authors: Caldera
authors: Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka.
authors: W A Janendra M
authors: WA
authors: De Costa
authors: Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.
authors: F Ian
authors: FI
authors: Woodward
authors: Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.
authors: Janice A
authors: JA
authors: Lake
authors: Department of Plant Sciences, Faculty of Science, University of Colombo, Colombo, Sri Lanka.
authors: Sudheera M W
authors: SM
authors: Ranwala
mesh_terms: D000064:Acclimatization; D000531:Altitude; D017360:Arabidopsis / Q000187:drug effects* / Q000502:physiology; D001272:Atmosphere; D002245:Carbon Dioxide / Q000494:pharmacology*; D002247:Carbon Isotopes / Q000032:analysis; D017753:Ecosystem; D060146:Ecotype; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology; D014867:Water / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D014867:Water; D002245:Carbon Dioxide