Hormonal control of growth habit in determinate lablab bean (Lablab purpureus)

Determinate lablab bean (Lablab purpureus) was treated with various plant hormones. Gibberellin (GA(3)) partly induced the indeterminate growth of plants grown under non-inductive conditions. Cytokinins (kinetin and benzyladenine) retained the determinate growth habit under inductive conditions for indeterminate growth. Endogenous contents of gibberellins and auxin were higher in the plants under inductive conditions than in those under non-inductive conditions, while the reverse was true for the endogenous contents of cytokinins. It is suggested that in determinate lablab bean gibberellin(s) and/or auxin(s) induce indeterminate growth habit in long days and high temperatures, while cytokinin(s) sustain determinate growth in short days and low temperature conditions.