Journal
PLANT SCIENCE
Volume 159, Issue 1, Pages 1-5Publisher
ELSEVIER IRELAND LTD
DOI: 10.1016/S0168-9452(00)00292-2
Keywords
Avicennia germinans; mangroves; salinity; gland secretion; total-reflection X-ray fluorescence; trace element analysis
Categories
Ask authors/readers for more resources
The aim here was to use total-reflection X-ray fluorescence (TXRF) to determine the elemental composition (besides Na), and the relative contribution of each element in leaf secretion of the mangrove species Avicennia germinans, grown under contrasting salinities (0-865 mol m(-3) NaCl). Na was determined by conventional atomic absorption spectrometry (AAS). Total secretion was 2.00 +/- 0.28 mmol m(-2) per day in control plants (at 0 NaCl) and increased progressively up to 46.87 +/- 7.14 mmol m(-2) per day at 865 mol m(-3) NaCl. Na and Cl accounted for 85.91 +/- 1.81% of the total secretion in control plants and about 96.32 +/- 0.30% in salt-treated plants. The excretion of Na exceeded that of CI when salinity increased and this led to a progressive increase in Na/Cl ratios from 0.46 +/- 0.02 in control plants up to 2.75 +/- 0.42 (at 865 mol m(-3) NaCl). Other elements were also secreted in sizeable amounts such as K, S, Ca, Br and Zn. However, the relative importance of these elements, in terms of total secretion, was considerable in control plants (15% of the total secretion) and declined significantly under salinity treatments (< 5% of the total secretion). In conclusion, TXRF has been shown to be a powerful tool allowing quantitative determination of Cl (1.2-13 mmol m(-2) per day), secreted in relatively large quantities, as well as other elements secreted in intermediate (S, Ca and K; 0.07-1.00 mmol m(-2) per day) and in trace quantities (Br and Zn; 0.6-4 pmol m(-2) per day). (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available