Apical Control of Flowering in an Orchid Hybrid, Aranda Deborah

Decapitation induced flowering in an orchid hybrid, Aranda Deborah.This flowering response was observed in both mature plants andcuttings. Flowering could also be induced by stem incisions. The flowering responses of the decapitated plants were shownto be inhibited by a continuous supply of 10^–4 M IAA solution.However, once the auxin supply was interrupted, floral initiationtook place. Renewed supply of exogenous auxin could not arrestfurther development of the inflorescence. Gibberellic acid had no significant effect on the floweringresponse of decapitated plants. CCC at 10^–2 M concentrationcaused slight decrease in the number of floral initials developedafter decapitation.