Protein and peroxidase changes in various root-cell fractions of two upland rice cultivars differing in Al tolerance

The quantitative changes in proteins and peroxidases associated with Al tox icity were investigated in various root-cell fractions of upland rice culti vars that differ in Al tolerance. The impact of Al on growth of the Al-sens itive rice cultivar IR45 was related to a marked reduction of protein conte nt in cytoplasm and an increase in the covalently-bound cell wall fractions . Regardless of cellular fractions, Al also induced peroxidase activities i n IR45 indicating a root-damage response to Al. In contrast, the Al toleran t rice cultivar BG35 maintained the content of cellular proteins and enzyme activities under Al stress. (C) 2001 Elsevier Science B.V. All rights rese rved.