The results
demonstrated that Al inhibited the growth of soybean root systems and severely damaged root cells. In
contrast to the Al-resistant cultivar, the Al-sensitive cultivar Z.3 showed a larger plasma membrane
permeability than Z.2 when treated with Al. In addition, the root elongation, activity, appearance of root
tips and root hair zone were all altered by Al treatments. For example, after the 10 mg L1 Al treatment,
the number of mitochondria had proliferated significantly in the root tip cells; plasmolysis was observed
in the 30 mg L1 Al treatment; and the cell wall had ruptured and the cellular contents had disappeared
in the high-level Al treatments. The results of our study showed in detail how soybean roots changed
physiologically in response to Al stress