Effects of Light Quality on Flowering and Physiological Parameters of Cymbidium ensifolium ‘Longyan Su’

As a highly valued orchid species, <i>Cymbidium ensifolium</i> (<i>C. ensifolium</i>) exhibits a natural flowering period mainly from July to September, which does not align with the market demand and shows low flowering quality, thereby significantly constraining the development of the <i>C. ensifolium</i> floriculture industry. To address this key issue, the study used <i>C. ensifolium</i> 'Longyan Su' as the experimental material, with white light as the control and composite light with varying ratios of red and blue light as the treatments, and investigated the influence of light quality on flowering. The results showed that blue light could significantly advance the flowering time, while red light could markedly improve the flower quality. Blue light promoted the accumulation of soluble protein and soluble sugar during flower bud differentiation, while red light enhanced their accumulation during floral organ development. During the flower bud differentiation and development stage, blue light increased the synthesis of abscisic acid (ABA) in leaves, and red light promoted the production of gibberellic acid (GA₃) and zeatin riboside (ZR). The study provides an important foundation and reference for further analysis of the flowering mechanism of <i>C. ensifolium</i> under different light quality treatments, and also provides technical support for flowering regulation of orchids in practical production.