Influence of shading intensity and gibberellic acid on growth, flowering and postharvest quality of gerbera (Gerbera jamesonii bolus ex hook.) under protected conditions

Abstract

An experiment was conducted to evaluate the effect of different shading intensities and gibberellic acid (GA?) concentrations on growth, flowering and postharvest attributes of gerbera (Gerbera jamesonii Bolus ex Hook.). The study comprised nine treatment combinations involving three shading levels (no shading, 50% shading and 75% shading) and three GA? concentrations (0, 150 and 250 ppm). The experiment was laid out in a factorial randomized block design with three replications. Significant differences were observed among treatments for all growth and flowering parameters. The combination of 50% shading with 250 ppm GA? recorded the maximum plant height (45.33 cm), number of leaves (28.12), flower diameter (12.93 cm), flower stalk length (54.13 cm), number of flowers per plant (22.66) and vase life (12.76 days), along with the minimum days to first flowering (41.23 days). The control treatment (no shading without GA?) recorded the poorest performance for most parameters. The results clearly indicate that moderate shading combined with higher GA? concentration significantly enhances vegetative growth, flowering quality and yield of gerbera under protected conditions.