Abstract
Drought, as the primary abiotic stress constraining global agriculture and ecological stability, exerts a decisive impact on the survival and fitness of Festuca rubra L. (F. rubra) in arid and semi-arid habitats. Deciphering the molecular basis and regulatory networks underlying drought tolerance is essential for cultivation and genetic improvement of F. rubra. Here, we integrate the transcriptional analysis with functional analysis to elucidate the mechanisms response to drought. Pairwise comparison of drought-stressed, control, and rewatered samples revealed distinct transcriptional responses. A total of 1,296 DEGs were identified in the DS vs CK comparison, while 3,535 and 3,941 DEGs were detected in the RW vs DS and RW vs CK comparisons, respectively. Further analyses identified 222 transcription factors with putative roles in mediating drought resistance. Quantitative real-time PCR (qRT-PCR) confirmed the expression patterns of six selected DEGs, laying a foundation for subsequent functional investigations. Additionally, evolutionary analysis of the CLE families showed that CLE25 is highly conserved in rice and Arabidopsis compared with F. rubra. The phenotype demonstrated that CLE25-mediated signaling pathway involving in regulating drought response in F. rubra. Our study was the first to study the regulatory mechanism of drought resistance of F. rubra with transcriptome methods and functional analysis identified the CLE25-mediated signaling pathway response to drought, which provides genetic resources for the breeding of drought-resistant varieties.