Volume 18, Issue 45 (6-2008)
Abstract
Aluminum is one of the most abundant minerals in the soil, comprising approximately 7%. At neutral or weakly acidic PH, Aluminum exists in the form of insoluble aluminosilicate or oxide. However, as the soil becomes more acid, aluminum is solubilized into a phytotoxic form. Aluminum is, therefore a major growth limiting factor especially root growth in acidic soils. It is estimated that approximately 30-40% of arable land in the world is acid soil. Furthermore, the acidity of the soil is gradually increasing as a result of environmental problems including acid rain. Thus, Aluminum toxicity is really an important issue. Under such situations, attention has been paid to improving the agricultural production in acid soil. Inhibition of rapid root growth is reported in some plants. Also, it is suggested that aluminum accumulates primarily and predominantly in the root apoplast where the pectin matrix with its negative changes is a major binding site. This study was undertaken to investigate the effect of aluminum on the amount of cell wall components of tobacco cells. In the present research, cell-cultured tobacco cell (Nicotiana tabacum L. CV. Burley 21) have been used as a plant cell model. After treatment with aluminum for 24 h, cells were harvested. Then, cell wall polysaccharides such as pectin, cellulose, Hemicellulose A and B were isolated from cell wall. Also,cell viability, aluminum absorption by cells and growth were measured. The results indicated that Al-induced increase in the amount of pectin and hemicellulose A. In these cells however, cellulose content reduced with 30µmol but not in the treatment with 60µmol of aluminum. Also loss of cell viability decreased cell growth
