Effects of Pb and Zn on the growth and physiological response of Sesuvium portulacastrum Sesuvium portulacastrum, A Promising Hhalophyte in Research and Application Cloning of Salt Tolerance-Related cDNAs from the Mangrove Plant Sesuvium portulacastrum L. The physiological characteristics of salt-tolerance in Sesuvium portulacastrum L. Ultrastructure of Sesuvium portulacastrum Samphire Mesophyll Cell under Hg2+ Stress MERCURY TOLERANCE AND ACCUMULATION IN THE HALOPHYTE SESUVIUM PORTULACASTRUM