Table_2_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，冷害与干旱被视为最为严峻的两种非生物胁迫。冰草（Poa crymophila）在青藏高原广泛种植，表现出强大的耐受性。本研究通过剖析基因表达模式及代谢组学相关的转录组共表达网络，对冰草对上述两种胁迫的适应性进行了表征。（1）具有胁迫耐受性的基因和代谢物在冷害和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展现出强大的恢复力。（2）此外，冷害和干旱激活了缺氧和UV-B适应性基因，这表明长期生活在高原上能够产生特殊的适应性。（3）苯乙胺、多胺和氨基酸，尤其是N′，N″，N′″-对香豆酰基肉桂酰基咖啡酰基精胺、腐胺和精氨酸，在恶劣环境中发挥着关键作用。冰草（P. crymophila）对干旱和冷害的灵活响应和快速恢复策略，是其耐力和恢复力的关键因素。在本研究中，我们展示了冰草的全面胁迫响应图谱，并为未来的牧草改良提供了众多候选基因或代谢物。