Both acropetal and basipetal translocations of Cu at different
exposure times were examined in H. verticillata. Each root or shoot
was exposed to 128 lg L1 Cu solution in separate containers, except
in the case of the controls. There were four replicates in each
treatment and each replicate consisted of two plants. Plants were
sampled periodically up to 96 h Cu exposure to investigate Cu
transportation in plants and subcellular distributions of Cu in different
tissues. Each plant was cut between containers, washed
carefully with de-ionized water, and then divided into leaves,
stems, roots, and air-exposed parts were removed. The samples
were blotted dry and fresh weights (FW) were recorded, and frozen
in liquid N2 until use.