Pathways of cadmium fluxes in the root of the halophyte Suaeda salsa

摘要

Halophyte plants offer a greater potential for phytoremediation research for reducing the levels of toxic metals from saline soils than salt sensitive plants. Using the scanning ion-selective electrode technique, we analyzed the pattern and rate of Cd~(2+) fluxes at different regions of the root apex of Suaeda salsa. The Cd~(2+) influx in the rhizosphere was greatest near the root tip (within 150 urn of the tip). The results indicated that Cd~(2+) influx into roots was significantly suppressed by the pre-treatment or in the presence of two kinds of Ca~(2+) channel blockers; LaCb and verapamil. The Cd~(2+) influx was also reduced by N-ethylmaleimide, a thiol blocker. Cd content determination and labeling of Cd using fluorescent dye support our conclusion. The results of this study provide a more stable theoretical basis for the phytoremediation of Cd contamination in saline soils of coastal zones.