caa a22 4500 397520751 CHVBK 20180308164632.0 cr unu---uuuuu 161202e199506 xx s 000 0 eng 10.1093/jxb/46.6.623 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.6.623 Responses of the stomata of Aster tripolium to calcium and sodium ions in relation to salinity tolerance [Elektronische Daten] [L.K.R.R. Perera, M. F. Robinson, T.A. Mansfield] In previous work, the stomata of the maritime halophyte Aster tripolium L. were shown to close when NaCl concentrations rise in the vicinity of the guard cells. Further studies have now revealed important effects of calcium on the ionic responses of the stomata. When the guard cells were presented with KCl, Ca2+ suppressed opening in a manner similar to that which has become familiar in other species such as Commelina communis L. However, in the presence of NaCl, Ca2+ had the opposite effect, reducing the closing response to NaCl. This pattern of behaviour is discussed in relation to known salt effects on membranes, but the underlying physiological basis remains obscure. A previous study led to the hypothesis that the closing response of the stomata to Na+ ions may make an important contribution to the salinity tolerance of this species. Here we report that increasing supplies of Ca2+ ions reduce the effect of salinity on stomatal conductance in the whole plant as well as in the isolated epidermis. This finding is consistent with the well established role of calcium in increasing resistance to salinity: in the presence of high calcium the plant can tolerate a greater salt intake, and hence there is a reduced need for transpiration to be restricted by partial stomatal closure. © Oxford University Press Research Papers nationallicence Sodium nationallicence calcium nationallicence Aster tripolium nationallicence stomata nationallicence salinity tolerance nationallicence Perera L.K.R.R. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut Robinson M. F. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut Mansfield T.A. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut Journal of Experimental Botany Oxford University Press 46/6(1995-06), 623-629 0022-0957 46:6<623 1995 46 exbotj https://doi.org/10.1093/jxb/46.6.623 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.6.623 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Perera L.K.R.R. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut NATIONALLICENCE 700 1- Robinson M. F. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut NATIONALLICENCE 700 1- Mansfield T.A. Institute of Environmental and Biological Sciences, Division of Biological Sciences, Lancaster University, Lancaster LA1 4YQ, UK aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/6(1995-06), 623-629 0022-0957 46:6<623 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford