title: Natural variation in stomatal responses to environmental changes among Arabidopsis thaliana ecotypes.
abstract: Stomata are small pores surrounded by guard cells that regulate gas exchange between plants and the atmosphere. Guard cells integrate multiple environmental signals and control the aperture width to ensure appropriate stomatal function for plant survival. Leaf temperature can be used as an indirect indicator of stomatal conductance to environmental signals. In this study, leaf thermal imaging of 374 Arabidopsis ecotypes was performed to assess their stomatal responses to changes in environmental CO2 concentrations. We identified three ecotypes, Köln (Kl-4), Gabelstein (Ga-0), and Chisdra (Chi-1), that have particularly low responsiveness to changes in CO2 concentrations. We next investigated stomatal responses to other environmental signals in these selected ecotypes, with Col-0 as the reference. The stomatal responses to light were also reduced in the three selected ecotypes when compared with Col-0. In contrast, their stomatal responses to changes in humidity were similar to those of Col-0. Of note, the responses to abscisic acid, a plant hormone involved in the adaptation of plants to reduced water availability, were not entirely consistent with the responses to humidity. This study demonstrates that the stomatal responses to CO2 and light share closely associated signaling mechanisms that are not generally correlated with humidity signaling pathways in these ecotypes. The results might reflect differences between ecotypes in intrinsic response mechanisms to environmental signals.
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Keina
authors.initials: K
authors.lastname: Monda
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Juntaro
authors.initials: J
authors.lastname: Negi
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Konishi
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Shinobu
authors.initials: S
authors.lastname: Ishikawa
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Mimi
authors.initials: M
authors.lastname: Hashimoto-Sugimoto
authors.affiliation: RIKEN BioResource Center, Koyadai, Tsukuba, Ibaraki, Japan.
authors.forename: Nobuharu
authors.initials: N
authors.lastname: Goto
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Koh
authors.initials: K
authors.lastname: Iba
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D002245:Carbon Dioxide / Q000032:analysis; D004777:Environment; D006813:Humidity; D008027:Light; D054046:Plant Stomata / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D002245:Carbon Dioxide