Gibberellin-Auxin Interaction in Pea Stem Elongation

Gibberellin-auxin interaction in pea stem elongation.

Joint application of gibberellic acid and indole-3-acetic acid to excised stem sections, terminal cuttings, and decapitated plants of a green dwarf pea results in a markedly synergistic growth response to these hormones. Synergism in green tall pea stem sections is comparatively small, although growth is kinetically indistinguishable from similarly treated dwarf sections.Gibberellin-induced gro...

Auxin regulation of the gibberellin pathway in pea.

The auxin indole-3-acetic acid (IAA) has been shown to promote the biosynthesis of the active gibberellin (GA(1)) in shoots of pea (Pisum sativum). We used northern analysis to investigate the timing of IAA-induced changes in transcript levels of PsGA3ox1 (Mendel's LE), PsGA2ox1, PsGA2ox2, and PsGA20ox1, key genes for the later stages of GA(1) biosynthesis and metabolism in pea. Rapid (2-4 h) c...

Auxin - Gibberellin Interaction in Apical Dominance " 2

Indoleacetic acid and gibberellic acid were added to decapitated lightgrown 'Alaska' pea seedlings as substitutes for the intact apex in the control of apical dotiinance. Of various concentrations and combinations tried, a conrbintation of 1 % indoleacetic acid 1 % gibberellic acid was the most inihibiting to side bud growth. The greatest degree of hormonally induced side bud inhibition was ach...

Thermoperiodic stem elongation involves transcriptional regulation of gibberellin deactivation in pea.

The physiological basis of thermoperiodic stem elongation is as yet poorly understood. Thermoperiodic control of gibberellin (GA) metabolism has been suggested as an underlying mechanism. We have investigated the influence of different day and night temperature combinations on GA levels, and diurnal steady-state expression of genes involved in GA biosynthesis (LS, LH, NA, PSGA20ox1, and PsGA3ox...

Comparative effects of hydrogen ions, carbon dioxide, and auxin on pea stem segment elongation.