Some physiological effects of abscisic acid on vicia faba plants II- changes in the endogenous auxins, growth inhibitors and certain oxidative enzymes

ABSTRACT

The activities of IAA-oxidase, peroxidase and catalase in the extract of radicles and plumules of Vicia faba seedlings throughout an experimental period of 192 hours germination are markers to get information about the effect of abscisic acid on the endogenous auxins and growth inhibitors. It was found that 10-6 M ABA markedly reduced the biological activities of auxins and markedly increased the growth inhibitors particularly the unsaturated lactone compounds and ABA. On the other hand, the low concentration of ABA [10-9 M] induced opposite changes. The activities of IAA-oxidase and peroxidase were increased while the activity of catalase was decreased at all concentrations of ABA used