Influence of Gibberellic Acid (GA3) and Benzyladenine (BA) on Growth Dynamics, Floral Development, and Bulb Formation in L.A. Hybrid Lilium Cultivar under Poly House Conditions

Abstract

The present study investigated the influence of GA3 and BA on the growth dynamics, floral development, and bulb formation in the L.A. Hybrid Lilium cultivar under polyhouse conditions at the Horticulture Research Farm, SHUATS, Prayagraj, during the period November 2024 to March 2025. A Randomized Block Design (RBD) with nine treatments and three replications was employed to evaluate a range of morphological, physiological, and economic parameters. GA3 and BA were applied as foliar sprays at 30 and 45 days after planting. Among the treatments, T5 (GA3 100 ppm & BA 100 ppm) recorded the greatest vegetative growth with the highest number of leaves (115.55) and maximum plant height (117.13 cm). In contrast, T3 (BA 100 ppm alone) achieved the largest stem diameter (5.89 mm). T6 (GA3 100 ppm & BA 200 ppm) excelled in several critical parameters, including the highest chlorophyll content (80.18 SPAD units), earliest bud initiation (47.67 days), longest flower bud length (11.22 cm), highest number of bulblets per plant (4.67), greatest bulb weight (45.05 g per plant), and maximum bulb yield (20.72 kg per 200 m²). Furthermore, T8 (GA3 150 ppm & BA 200 ppm) emerged as the top performer in enhancing floral characteristics. This treatment resulted in the longest time to first flowering (84.67 days), produced the highest number of buds per plant (8.86), maximum flower diameter (39.34 cm), extended flower longevity (self life of 11.33 days and vase life of 8.67 days), and the largest number of flowers recorded both per plant (8.86) and per 200 m² (39,392.55). Economically, T8 delivered the most favorable outcomes with a gross return of Rs. 666,600, a net return of Rs. 500,380.12 per 200 m², and a benefit-cost (B:C) ratio of 3.01 from flower production.