Functional Study on the Key Gene LaLBD37 Related to the Lily Bulblets Formation

Abstract

Oriental hybrid lilies, known for their vibrant colors, diverse flower shapes, and long blooming seasons, require annual bulb propagation in horticultural production. This necessity can lead to higher production costs and limit their use in landscaping. The LA hybrid lily ‘Aladdin’ has shown strong self-reproduction capabilities in optimal cultivation environments, producing numerous high-quality underground stem bulblets. This makes it a valuable model for studying bulblet formation in lilies under natural conditions. Through transcriptome data analysis of different developmental stages of ‘Aladdin’ bulblets, the LaLBD37 gene, linked to bulblet formation, was identified. Bioinformatics analysis, subcellular localization studies, and transcriptional activation activity tests were conducted to understand the characteristics of LaLBD37. By introducing the LaLBD37 gene into ‘Sorbonne’ aseptic seedlings via Agrobacterium-mediated transformation, resistant plants were obtained. Positive plants were identified through various methods such as GUS activity detection, PCR, and fluorescence quantitative PCR. Phenotypic changes in positive plants were observed, and various physiological indicators were measured to confirm the role of LaLBD37 in bulblet formation, including soluble sugar content, starch content, sucrose synthase activity, and endogenous hormone levels. The findings suggest that the LaLBD37 gene plays a significant role in promoting the development of lily bulblets, offering insights for enhancing the reproductive capacity of Oriental hybrid lilies and exploring the molecular mechanisms involved in lily bulb regeneration.