###### Abstract  
Volatile terpenoids (VTs) are key secondary metabolites that play dual roles as endogenous antioxidants and airborne signals in plants under abiotic stress. Their biosynthesis is orchestrated via the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, with metabolic plasticity regulated by transcription factors, phytohormonal crosstalk, and stress-responsive elements. Recent advances have revealed that VTs such as isoprene, monoterpenes, and sesquiterpenes help mitigate oxidative stress by scavenging reactive oxygen species (ROS) and modulating antioxidant enzyme systems. However, regulatory mechanisms of stress-induced VT emissions remain fragmented and species-dependent. This review synthesizes current knowledge of VT biosynthesis and emission under abiotic stress, highlights their antioxidant functions and regulatory architecture, and underscores their protective roles in redox homeostasis and stress signal transduction. By identifying key metabolic nodes (e.g., TPS, DXS and MYC2) and stress-responsive pathways, we propose potential molecular targets for the development of stress-resilient cultivars. The integration of VT-based traits into breeding strategies and production-oriented metabolic engineering offers promising avenues for improving crop performance, reducing oxidative damage, and supporting sustainable agricultural systems. volatile terpenoids; abiotic stress; biosynthesis; volatile emission +
Footnote †: journal:  
0000-0001-5877-4000-0000-0000-0000-0000-0000-0000-0000-0000-0000-0  
Notably, maize (_Zea mays_) plants under herbivore attack by _Diabrotica virgifera_ larvae accumulate the sesquiterpene (E)-\(\beta\)-caryophyllene, which recruits entomopathogenic nematodes (_Heterorhabditis bacteriophora_) rather than directly deterring the pest, illustrating a sophisticated tripartite interaction among plants, herbivores, and nematodes [9]. Acting as airborne sentinels, VTs mediate interplant alarm signaling by triggering preemptive upregulation of jasmonate-dependent defense pathways in neighboring plants, thereby establishing community-wide resistance networks. A seminal study on spider mite-infested lima bean plants (_Phaseolus lunatus_) demonstrated that herbivore-induced VT emissions enable intact neighboring individuals to preemptively upregulate jasmonate-dependent defense pathways, significantly enhancing pest resistance [10]. Beyond their roles in biotic interactions, VTs enhance abiotic stress resilience via distinct biochemical mechanisms. Isoprene and monoterepenes stabilize thylakoid membrane fluidity under heat stress, preserving photosynthetic efficiency, while also functioning as phytoantioxidants to mitigate oxidative stress under drought conditions [11]. The commercial exploitation of VT diversity continues to expand, with monoterepenes (e.g., limonene and linalool) serving as core ingredients in the flavor and fragrance industries and the diterpenoid taxol remaining a frontline chemotherapeutic agent. Emerging evidence suggests that \(\alpha\)-pinene emissions from coniferous forests exert potent anxiolytic effects through olfactory-mediated neuroendocrine modulation, inspiring advancements in forest-based phytotherapeutic applications. VTs play multifaceted roles in both plant survival strategies and human societal development. Recent research has extensively studied VT emission rates and their spatiotemporal patterns, highlighting their dynamic regulation by biotic factors (e.g., plant ontogenetic stages and cross-kingdom interactions) and abiotic variables such as temperature gradients, relative humidity, seasonal fluctuations, and solar irradiance [12]. Once released into the atmosphere, VTs fulfill diverse physiological roles, ranging from ecological signaling to biochemical defense. VTs play a central role in plant responses to abiotic stress, functioning not only as endogenous antioxidants that regulate redox homeostasis but also as key mediators of signal transduction and environmental adaptation.