Regulatory Mechanisms of Exogenous Gibberellin on Seed Germination and Transcriptomic Responses in Lomatogonium rotatum

Gibberellins (GAs) are essential phytohormones that regulate seed dormancy release and germination. Lomatogonium rotatum (L.) Fries ex Nym is a traditional medicinal plant whose seed germination is often hindered by physiological dormancy. In this study, we systematically investigated the effects of exogenous GA3 on the seed germination of L. rotatum and elucidated the underlying molecular regulatory mechanisms via transcriptomic analysis. GA3 treatment (500 mg/L for 24 h) significantly improved the germination rate, vigor index, and other germination traits. RNA-seq analysis identified time-dependent transcriptional changes in GA3-treated seeds across three developmental stages (24 h, 72 h, and 96 h). KEGG enrichment and K-means clustering revealed dynamic actiSvation of hormonal signaling, secondary metabolism, and DNA replication pathways. WGCNA uncovered two hormone-responsive co-expression modules (Red and Lightcyan) corresponding to early and late stages of germination, respectively. Key genes related to ABA and GA biosynthesis and signal transduction showed phase-specific expression, highlighting the coordinated hormonal regulation during seed germination. Our findings provide new insights into the molecular basis of GA3-regulated seed germination and offer theoretical support for the cultivation and utilization of L. rotatum.