Development of an Optimized Scale Propagation Protocol for Lilium LA Hybrid ‘Corona’ Under Subtropical Conditions
Abstract
Lilium ( Lilium hybrida ) is one of the most important ornamental bulbous crops grown around the world; however, its commercial cultivation is constrained by the low multiplication rate of bulbs. Although scale propagation has been widely used for vegetative multiplication, most studies have been conducted under temperate conditions, leaving limited information on optimizing plant growth regulator treatments for efficient bulblet production under subtropical conditions. Therefore, the present study evaluated the effects of different concentrations of gibberellic acid (GA 3 ), naphthalene acetic acid (NAA), indole‐3‐butyric acid (IBA), 6‐benzylaminopurine (6‐BAP), and KNO 3 on detached bulb scales of Lilium LA Hybrid ‘Corona’ under subtropical conditions. Detached outer and middle bulb scales were treated with different plant growth regulator solutions and grown in a cocopeat + perlite (1:1) medium under a naturally ventilated polyhouse over two growth periods, after which bulblet production, rooting, propagation efficiency, and selected biochemical attributes were evaluated. Among the treatments, GA 3 at 150 mg L −1 significantly enhanced bulblet production by improving bulblet size, biomass, propagation coefficient, scale differentiation, and carbohydrate accumulation, whereas 6‐BAP promoted the formation of a greater number of comparatively smaller bulblets. The enhanced bulblet development and propagation efficiency achieved with GA 3 can facilitate faster production of uniform, high‐quality planting material from a limited number of mother bulbs, reducing the multiplication cycle and supporting large‐scale commercial lily production under subtropical conditions. The findings highlight the potential of GA 3 ‐mediated scale propagation as a sustainable and efficient approach for overcoming the limitations of conventional bulb multiplication and strengthening commercial Lilium production systems in subtropical regions.