Selective herbicidal activity of iodide in relation to iodide accumulation and foliar peroxidase activity

Abstract

The response of several plant species (dwarf bean, tomato, pea, cabbage, nettle and buttercup) to treatment with iodide has been investigated. Selective toxicity of iodide has been confirmed, sensitive species exhibiting severe desiccation of the leaves.Iodination of cellular components following treatment of bean leaves with iodide has been demonstrated, indicating that the iodide undergoes intracellular oxidation to iodine. This is thought to be brought about by peroxidase enzymes. Peroxidase activities (in relation to iodide oxidation) in the leaves of the plants studied have been determined. Although very low peroxidase activities are correlated with iodide tolerance, the results obtained indicate that the extent to which iodide accumulates in the leaves is also an important contributory factor in iodide selective toxicity.