title: The effects of 3,5-diiodo-4-hydroxybenzoic acid on the oxidation of IAA and auxin-induced ethylene production by cress root segments.
abstract: In previous research here, 3,5-diiodo-4-hydroxybenzoic acid (DIHB) was shown to promote the elongation of roots of cress (Lepidium sativum) seedlings growing in light, and to inhibit the auxin-induced production of ethylene in this tissue. Although DIHB is a cofactor for the oxidation of indole-3-acetic acid (IAA) by horse-radish peroxidase, it inhibits the decarboxylation of [1-(14)C]IAA by segments excised from cress roots. The inhibition by DIHB of ethylene production by this tissue does not, therefore, arise from a reduction of IAA levels. These findings are discussed in relation to the effects of DIHB on cress root growth.
authors.affiliation: Agricultural Research Council Plant Growth Substance and Systemic Fungicide Unit, Wye College (University of London), TN25 5AH, Ashford, Kent, U.K..
authors.forename: M L
authors.initials: ML
authors.lastname: Robert
authors.forename: H F
authors.initials: HF
authors.lastname: Taylor
authors.forename: R L
authors.initials: RL
authors.lastname: Wain