TY - JOUR
T1 - Changes in the main osmotica during the development of Kandelia candel hypocotyls and after mature hypocotyls were transplanted in solutions with different salinities
AU - Wang, W. Q.
AU - Ke, L.
AU - Tam, N. F.Y.
AU - Wong, Y. S.
N1 - Funding Information:
Acknowledgements Thanks to Dr. N.C. Chen and technicians of BCH for help in sample analyses. The research is supported by NSFC (No. 302031). The experiments comply with the current laws of the People’s Republic of China and Hong Kong.
PY - 2002
Y1 - 2002
N2 - No direct correlation was found between salt tolerance and vivipary. Ion (Mg2+, Ca2+, Na+, K+ and Cl-) concentrations on a dry weight basis (mg/g) and on a milli-molar basis per mass of water in fresh tissue (mM) were followed during the development of Kandelia candel hypocotyls and after mature hypocotyls were transplanted under different treatments (salinities of 0, 15 and 30‰). During hypocotyl development, ion concentrations on a dry weight basis declined especially for Mg2+ and Ca2+. The decrease could not be explained by the decrease in water content. However, the concentrations on a milli-molar basis did not decrease, but increased slightly at a later stage. Mass balance studies showed that the hypocotyl development was a salt accumulation process, especially for Na+, K+ and Cl-. Mangrove propagules adapt themselves to hyposaline environments by accumulating salt, especially before leaving their parent plants. Substrate salinity showed no modification of trends in Ca2+ and Mg2+ after transplantation, increasing rapidly in the beginning, then remaining at a high level and declining rapidly when roots formed. There were no significant differences in Mg2+ and Ca2+ concentration among treatments. The significance of salt level changes during hypocotyl development to salt tolerance remains to be clarified. After hypocotyl transplantation, concentrations of Na+, K+ and C1- increased gradually after insignificantly early changes. However, once roots formed, K+, Na+ and Cl- concentrations increased rapidly under 15‰ and 30‰ salinity treatments, and declined or remained constant when salinity was zero. If corrected for water content, it was found that when roots formed there was a leakage of ions in K. candel hypocotyl during the zero salinity treatment. There was a faster ion uptake at salinities of 15‰ and 30‰. This showed that once the root system is formed, exchange with the environment becomes more rapid.
AB - No direct correlation was found between salt tolerance and vivipary. Ion (Mg2+, Ca2+, Na+, K+ and Cl-) concentrations on a dry weight basis (mg/g) and on a milli-molar basis per mass of water in fresh tissue (mM) were followed during the development of Kandelia candel hypocotyls and after mature hypocotyls were transplanted under different treatments (salinities of 0, 15 and 30‰). During hypocotyl development, ion concentrations on a dry weight basis declined especially for Mg2+ and Ca2+. The decrease could not be explained by the decrease in water content. However, the concentrations on a milli-molar basis did not decrease, but increased slightly at a later stage. Mass balance studies showed that the hypocotyl development was a salt accumulation process, especially for Na+, K+ and Cl-. Mangrove propagules adapt themselves to hyposaline environments by accumulating salt, especially before leaving their parent plants. Substrate salinity showed no modification of trends in Ca2+ and Mg2+ after transplantation, increasing rapidly in the beginning, then remaining at a high level and declining rapidly when roots formed. There were no significant differences in Mg2+ and Ca2+ concentration among treatments. The significance of salt level changes during hypocotyl development to salt tolerance remains to be clarified. After hypocotyl transplantation, concentrations of Na+, K+ and C1- increased gradually after insignificantly early changes. However, once roots formed, K+, Na+ and Cl- concentrations increased rapidly under 15‰ and 30‰ salinity treatments, and declined or remained constant when salinity was zero. If corrected for water content, it was found that when roots formed there was a leakage of ions in K. candel hypocotyl during the zero salinity treatment. There was a faster ion uptake at salinities of 15‰ and 30‰. This showed that once the root system is formed, exchange with the environment becomes more rapid.
UR - http://www.scopus.com/inward/record.url?scp=0036962839&partnerID=8YFLogxK
U2 - 10.1007/s00227-002-0951-1
DO - 10.1007/s00227-002-0951-1
M3 - Article
AN - SCOPUS:0036962839
SN - 0025-3162
VL - 141
SP - 1029
EP - 1034
JO - Marine Biology
JF - Marine Biology
IS - 6
ER -