Integrated Physiological and Transcriptomic Analysis Reveals Key Drought Resistance Mechanisms in Festuca rubra
Drought stress significantly impairs plant growth and productivity. Festuca rubra L (F.rubra) is a perennial turfgrass that is valued for its strong drought tolerance. However, the integrated physiological and molecular mechanisms underlying this trait remain insufficiently explored. In this study, F. rubra was subjected to 21 days of drought stress, after which systematic physiological and transcriptomic analyses were conducted. Plants exhibiting signs of drought stress demonstrated a substantial decline in key photosynthetic parameters, accompanied by a notable upregulation in antioxidant enzyme activities. Concurrently, these plants exhibited an augmented accumulation of osmoregulatory substances, including proline and soluble sugars. 25,063 differentially expressed genes (DEGs) were identified by transcriptome analysis, including AP2/ERF, NAC, and bHLH transcription factors. Gene ontology (GO) and KEGG enrichment revealed repression of photosynthesis and activation of plant hormone signal transduction and MAPK pathways. Key genes involved in proline biosynthesis and peroxisome function were markedly up-regulated, indicating enhanced osmotic adjustment and oxidative stress defence. The results of this study elucidate the coordinated drought response mechanisms in F. rubra and provide valuable genetic resources for improving drought tolerance in turfgrass and related crops.