title: [Effect of NaHCO3 stress on uptake and transportation of Na+, K+ and Ca2+ in three shrub species].
abstract: We detected absorption and transportation of ions in the leaves of Atriplex nummularia, Atriplex canescens and Lycium barbarum under NaHCO3 stress (300 mmol x L(-1)) by using atomic absorption spectrophotometry and non-invasive ion flux measurement. The results showed that leaves of the A. nummularia, A. canescens and L. barbarum exhibited a high capacity to induce the Na+ accumulation when compared with that of control. The higher the concentration of NaHCO3 treatment, the more Na+ accumulated in the leaves of the three plants under experimental condition. L. barbarum showed a higher Na+ efflux in the mesophyll cells, whereas A. nummularia and A. canescens showed a relative lower efflux. A lower K+ content and a higher Na+/K+ ratio were detected in leaves of A. nummularia and L. barbarum. However, a higher K+ content and a lower Na+/K+ ratio were seen in leaves of A. canescens. Due to induction of Ca2+ efflux under the NaHCO3 treatment, a lower Ca2+ content and a higher Na+/Ca2+ ratio were observed in L. barbarum. On the contrary, a higher Ca2+ influx was observed in A. nummularia and A. canescens. These results suggested that the three shrubs species had different Na+ segmentation strategies. The accumulation of Na+ inhibited Ca2+ absorption in leaves of L. barbarum, while in the A. nummularia and A. canescens, Ca2+ influx induced [Ca2+]cyt which preserved a less-depolarized PM and then inhibited K efflux. The maintaining of cellular K+/Na+ homeostasis in A. nummularia and A. canescens might be achieved by the induction of [Ca2+]cyt under the NaHCO3 treatment.
authors.forename: Gui-Lian
authors.initials: GL
authors.lastname: Mao
authors.forename: Guo-Qi
authors.initials: GQ
authors.lastname: Li
authors.forename: Xing
authors.initials: X
authors.lastname: Xu
authors.forename: Xin-Xue
authors.initials: XX
authors.lastname: Zhang
mesh_terms: D027466:Atriplex / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D006706:Homeostasis; D032305:Lycium / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D017693:Sodium Bicarbonate / Q000737:chemistry*; D013312:Stress, Physiological
chemical_list: D017693:Sodium Bicarbonate; D012964:Sodium; D011188:Potassium; D002118:Calcium