Fig. 5.

Effect of Si on Cd binding to the root cell wall. (A, B) Time-dependent binding of Cd to the cell wall of lsi1 and its wild type (WT1) (A), and lsi2 and its wild type (WT2) (B). (C) Cd concentration in root cell wall of lsi1, lsi2, and their wild types (WT1 and WT2). Root cell wall was prepared by boiling in methanol roots of seedlings (18 d old) pre-treated with or without 1 mM Si for 7 d. The Cd binding experiment was conducted by incubating the cell wall in a 0.5 mM CaCl₂ solution containing 50 µM Cd. An aliquot of 50 µl solution was sampled at different times up to 120 min. At the end of experiment, the root cell wall was collected and subjected to Cd determination by ICP-MS. Data are means±SD (n=3). Different lower-case letters indicate significant difference at P<0.05 by Duncan’s test.