tailieunhanh - Salt stress in the plant 1

Nitric oxide enhances salt secretion and Na+ sequestration in a mangrove plant, Avicennia marina, through increasing the expression of H+-ATPase and Na+/H+ antiporter under high salinity. | Tree Physiology Advance Access published October 28 2010 Tree Physiology 0 1-16 doi treephys tpq086 Nitric oxide enhances salt secretion and Na sequestration in a mangrove plant Avicennia marina through increasing the expression of H -ATPase and Na H antiporter under high salinity JUAN CHEN 1 QIANG XIAO 2 1 FEIHUA WU 1 5 XUEJUN DONG 3 JUNXIAN HE 4 ZHENMING PEI5 1 and HAILEI ZHENG1 6 1 Key Laboratory for Subtropical Wetland Ecosystem Research of MOE School of Life Sciences Xiamen University Xiamen 361005 People s Republic of China 2 Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei Institutes for Nationalities Enshi 445000 People s Republic of China 3 Central Grasslands Research Extension Center North Dakota State University Streeter ND 58483 USA 4 Institute of Plant Molecular Biology and Agricultural Biotechnology The Chinese University of Hong Kong Shatin Hong Kong SAR China 5 Department of Biology Duke University Durham NC 27708 USA 6 Corresponding author zhenghl@ Received May 31 2010 accepted August 29 2010 handling Editor Torgny Nasholm Summary Modulation of nitric oxide NO on ion homeostasis by enhancing salt secretion in the salt glands and Na sequestration into the vacuoles was investigated in a saltsecreting mangrove tree Avicennia marina Forsk. Vierh. The major results are as follows i under 400 mM NaCl treatment the application of 100 qM sodium nitroprusside SNP an NO donor significantly increased the density of salt crystals and salt secretion rate of the leaves along with maintaining a low Na to K ratio in the leaves. ii The measurement of element contents by X-ray microanalysis in the epidermis and transversal sections of A. marina leaves revealed that SNP 100 qM significantly increased the accumulation of Na in the epidermis and hypodermal cells particularly the Na to K ratio in the salt glands but no such effects were observed in the mesophyll cells. iii Using non-invasive micro-test technology .