[Cadmium accumulation, subcellular distribution, and chemical forms in Vitis vinifera cv. chardonnay grapevine]

A pot culture experiment was conducted to study the Cd absorption, Cd subcellular distribution, and Cd chemical forms in one-year old self-rooted Chardonnay and SO4 rootstock-grafted Chardonnay grapevine after root-irrigating with different concentration CdCl and CaCl2. In the grapevine, the absorbed Cd was mostly distributed in underground organs (root and rhizome). In treatment 4 mmol x L(-1) of CdCl2, 77.1% and 1.4% of the absorbed Cd in self-rooted Chardonnay were accumulated in underground organs and leaves, respectively, while 93.9% and 0.1% of the absorbed Cd in grafted Chardonnay were accumulated in the organs below graft position and in leaves, respectively. 5 mmol L(-1) of CaCl2 decreased the plant Cd absorption and accumulation, while 10 mmol x L(-1) of CaCl2 increased the plant Cd absorption and accumulation significantly. The Cd subcellular distribution in roots and leaves was in the order of cell wall > soluble fraction > organelle, and more than 50% of the Cd was accumulated in cell wall. In the roots, NaCl-extractable Cd had a major proportion, followed by HAc-extractable Cd, and water-extractable Cd. The contents of all the Cd chemical forms varied with the increasing concentration of Cd in the treatments.