Table_3_Flexible response and rapid recovery strategies of the plateau forage Poa crymophila to cold and drought.xlsx

Cold and drought stress are the two most severe abiotic stresses in alpine regions. Poa crymophila is widely grown in the Qinghai–Tibet Plateau with strong tolerance. Here, by profiling gene expression patterns and metabolomics-associated transcriptomics co-expression network, the acclimation of Poa crymophila to the two stresses was characterized. (1) The genes and metabolites with stress tolerance were induced by cold and drought, while those related with growth were inhibited, and most of them were restored faster after stresses disappeared. In particular, the genes for the photosynthesis system had strong resilience. (2) Additionally, cold and drought activated hypoxia and UV-B adaptation genes, indicating long-term life on the plateau could produce special adaptations. (3) Phenolamines, polyamines, and amino acids, especially N′,N″,N′″-p-coumaroyl-cinnamoyl-caffeoyl spermidine, putrescine, and arginine, play key roles in harsh environments. Flexible response and quick recovery are strategies for adaptation to drought and cold in P. crymophila, accounting for its robust tolerance and resilience. In this study, we presented a comprehensive stress response profile of P. crymophila and provided many candidate genes or metabolites for future forage improvement.

高寒地区中，寒冷与干旱是两种最为严峻的生态非生物胁迫。Poa crymophila 在青藏高原广泛种植，且表现出极强的耐受力。本研究通过对该物种基因表达模式及与代谢组学相关的转录组共表达网络进行剖析，揭示了其在两种胁迫条件下的适应机制。（1）耐受胁迫的基因与代谢产物在寒冷与干旱条件下被诱导表达，而与生长相关的基因则受到抑制，大部分基因在胁迫消失后恢复速度较快。特别是光合作用系统的基因表现出极强的恢复力。（2）此外，寒冷与干旱激活了缺氧与UV-B 适应性基因，这表明长期生活在高原环境中能够形成特殊适应性。（3）酚胺类、多胺类和氨基酸，尤其是N′,N″,N′″-对香豆酰基-肉桂酰基咖啡酰基精氨素、腐胺和精氨酸等，在恶劣环境中发挥着关键作用。P. crymophila 通过灵活的应答机制和快速的恢复策略，适应干旱与寒冷，这为其强大的耐受力与恢复力提供了保障。在本研究中，我们全面描绘了P. crymophila 的胁迫响应特征，并为未来牧草改良提供了众多候选基因或代谢产物。