Aluminium stimulated hydrogen peroxide production of germinating barley seeds

In spite of the localisation of Al in the root tips and loss of cell viability, the presence of Al (2-8 mM) during the first day of germination had no effect on germination capability and on the growth of emerging roots of barley seeds. At this stage of germination, considerable increase of hydrogen peroxide production was observed in Al-treated germinated seeds in comparison to control non-treated seeds. During the second day of germination, further Al uptake and loss of cell viability continued and significant root growth inhibition was observed. On the other hand, production of H2O2 decreased in comparison to the first day production, however was still higher than in control seedlings. Superoxide production and superoxide dismutase activity were inhibited by Al both 24 and 48 h after the onset of germination. The role of hydrogen peroxide and superoxide in relation to the seed germination, root growth, and cell viability during Al stress is discussed. (C)2003 Elsevier B.V. All rights reserved.