Effect of malformin on adventitious root formation and metabolism of indoleacetic acid-2-14C byPhaseolus vulgaris1

摘要

Malformin inhibited rooting on cuttings ofPhaseolus vulgaris. IAA antagonized malformin-induced inhibition of rooting, but malformin inhibited IAA-induced swelling on the base of the cuttings. It was suggested that IAA-induced swelling was mediated by ethylene. Malformin did not inhibit transport of root-promoting substances from upper portions of the cuttings or polar transport of IAA-2-14C, nor did it alter the melting point of DNA or the binding of DNA to histone. Although malformin appeared to alter the metabolism of IAA-2-14C, the effect may have been the result of a marked and selective stimulation of efflux of IAA-2-14C metabolites by malformin. Efflux of IAA or its metabolites may contribute toward inhibition of rooting by malformin.