Plants face various abiotic and biotic stresses in their environment, which they must overcome or compensate for. To minimize metabolic costs and stress defense expenses, plants prioritize first-line defense strategies in the apoplastic space, involving ascorbate, defensins, small peptides, and secondary metabolites. These strategies help prevent cellular processes from being affected. Additionally, symplastic mechanisms provide efficient stress defense through chemical antioxidants, antioxidative enzymes, secondary metabolites, defensins, and other peptides. Specialized transporters are involved in membrane exchange, though their identities remain unclear. Defense strategies also operate at the organ and whole-plant levels, including stomatal regulation and hypersensitive and systemic responses to prevent stress spread. At the ecosystem level, root exudation of signaling molecules and volatile organic compounds (VOCs) help defend against pathogens and pollutants. The mechanisms controlling these compounds and their perception are not fully understood. This review summarizes plant defense strategies from the cellular to ecosystem level, discusses their advantages and disadvantages, and highlights current research on the transport and regeneration of defense metabolites. It also outlines questions requiring further investigation. Key strategies include apoplastic and symplastic defense mechanisms, secondary metabolites, enzymatic activities, and defense proteins. These strategies help plants survive and grow under various stresses, though they may involve trade-offs with growth and development. The review emphasizes the importance of understanding these defense mechanisms for improving plant resilience to environmental challenges.Plants face various abiotic and biotic stresses in their environment, which they must overcome or compensate for. To minimize metabolic costs and stress defense expenses, plants prioritize first-line defense strategies in the apoplastic space, involving ascorbate, defensins, small peptides, and secondary metabolites. These strategies help prevent cellular processes from being affected. Additionally, symplastic mechanisms provide efficient stress defense through chemical antioxidants, antioxidative enzymes, secondary metabolites, defensins, and other peptides. Specialized transporters are involved in membrane exchange, though their identities remain unclear. Defense strategies also operate at the organ and whole-plant levels, including stomatal regulation and hypersensitive and systemic responses to prevent stress spread. At the ecosystem level, root exudation of signaling molecules and volatile organic compounds (VOCs) help defend against pathogens and pollutants. The mechanisms controlling these compounds and their perception are not fully understood. This review summarizes plant defense strategies from the cellular to ecosystem level, discusses their advantages and disadvantages, and highlights current research on the transport and regeneration of defense metabolites. It also outlines questions requiring further investigation. Key strategies include apoplastic and symplastic defense mechanisms, secondary metabolites, enzymatic activities, and defense proteins. These strategies help plants survive and grow under various stresses, though they may involve trade-offs with growth and development. The review emphasizes the importance of understanding these defense mechanisms for improving plant resilience to environmental challenges.