Insecticide - plant interaction: Carbofuran effect on indole-3-acetic acid metabolism and plant growth

Two metabolites of carbofuran insecticide, 2, 2- dimethyl-7-hydroxy-2, 3-dihydrobenzofuran (carbofuran phenol) and 2, 2-dimethyl-3, 7-dihydroxy-2, 3-dihydrobenzofuran, (3-hydroxy-carbofuran phenol) were found inhibitory to indole-3-acetic acid (IAA) oxidase. These metabolites stimulated plant growth in a pea stem segment assay with a low concentration of IAA, a plant hormone required for promoting growth. The close agreement of the results obtained from both growth and enzyme assays suggests an interaction of the carbofuran metabolites with IAA and a causal relationship between the inhibition of IAA oxidation and the promotion of plant growth as affected by the carbofuran metabolites.