Production of gladiolus submitted to gibberellic acid in a protected environment1

Abstract

Gladiolus is an important cut flower commercialized in Brazil, and the use of gibberellic acid (GA3) to cultivate it in a protected environment may promote the production of high quality flower spikes. This study aimed at evaluating the production of flower spikes and corms of gladiolus ('White Friendship' cultivar) submitted to high concentrations and application methods of gibberellic acid, in a protected environment. The experimental design was randomized blocks, in a 2 x 4 factorial arrangement, being two application methods (foliar spraying and corm soaking) and four concentrations (0 mg L-1, 250 mg L-1, 500 mg L-1 and 1,000 mg L-1) of gibberellic acid, with six replications and two plants per experimental unit. The following traits were evaluated: plant height, number of leaves per plant, marketable harvest point of flower spikes, number of florets per flower spike, flower panicle length, stem and floret diameter, corm perimeter, number of cormels per plant and production of corm fresh matter and leaf dry matter, flower spikes, corms and cormels. High concentrations of GA3 are not recommended for the production of flower spikes and corms of the gladiolus 'White Friendship' cultivar. The corm soaking application method anticipates the harvest of flower spikes and produces a higher number of cormels per plant. Regardless of the application method, the concentration of 550 mg L-1 of GA3 increases the cormel yield of the 'White Friendship' cultivar.

Gibberellin and polyamines in plant growth, development, and postharvest senescence of ornamental plants – a review

“…Tulip bulbs treated with 100 mg L -1 GA3 sprouted in significantly less number of days, exhibited higher sprouting percentage, more plant height, leaf area, leaf chlorophyll, photosynthesis rate, flower stalk length, stalk diameter, and fresh and dry stalk weight (Ramzan et al, 2014). Carvalho-Zanão et al (2016) studied the production of gladiolus submitted to gibberellic acid in a protected environment and observed that high concentrations of GA3 are not recommended for the production of flower spikes and corms of the 'White Friendship' gladiolus cultivar.…”