Gibberellic acid and 6-benzyladenine reduce time to flowering and improve flower quality of Laelia anceps

Abstract

The efficacy of plant growth regulators (PGRs) has been demonstrated in the flowering of economically significant orchid hybrids, but studies of their effects in wild species with commercial potential are scarce. The effect of three doses of gibberellic acid (GA3) and 6-benzyladenine (BA), individually or in combination, and a control without PGRs, were evaluated during three flowering periods in Laelia anceps subsp. anceps, in the temporal behavior of flowering, morpho-floral quality parameters and in potential residual effects and malformations. Significant effects were observed between the experimental periods and doses used, with a single application of PGRs in the first period reducing the days to visible flower induction (DVFI), days to anthesis (DAN) and days of flower life (DFL), mainly in the first period. There were no significant differences between doses for morpho-floral quality parameters within each period, but differences existed between experimental periods, where the life and size of the flower increased in the first period, and the number of flowers and flower stems increased significantly in the second period. The doses of 2.37 mg · L-1 BA + 100 mg · L-1 GA3 showed highest significant consistency in the reduction of DVFI, DAN and increase of DFL and flower stems in the study. There were no floral malformations, and a positive residual effect was observed in temporal variables in the second period. Most of the doses used encourage beneficial effects in the various aspects of flowering evaluated.