Phage therapy under multiple abiotic stresses: Systematic review on mechanisms of plant disease control

• First systematic synthesis of how multiple abiotic stresses—such as drought, salinity, heat, and pollutants—collectively affect bacteriophage stability, infectivity, and plant disease control efficacy. • Elucidates dual mechanisms of phage-mediated plant protection, encompassing both direct antibacterial actions (lysis, biofilm disruption, quorum sensing interference) and indirect ecological effects (microbiome modulation, immune priming). • Integrates stress physiology and microbiome ecology, proposing a conceptual “Phage–Plant Immunity–Stress Response Triangle” to explain phage roles in plant defense regulation under abiotic stress. • Highlights novel formulations—including polymer coatings, nano-gels, and encapsulation—that significantly enhance phage persistence under drought, UV, and salinity stress. • Proposes an integrated multi-layered strategy combining phages, beneficial microbes, nanocarriers, and hormonal regulators as a climate-resilient framework for sustainable crop protection. • Identifies key regulatory and socio-economic gaps, emphasizing the need for biosafety, policy harmonization, and equitable adoption to scale phage-based biocontrol globally. Bacterial phytopathogens remain a major obstruction to agricultural productivity, and their impacts are increasingly intensified by abiotic stresses such as salinity, drought, extreme temperature and heavy metal toxicity. Conventional chemical-based controls are proving unsustainable due to pathogen resistance, declining field efficacy, and environmental concerns, highlighting the need for alternative approaches. Bacteriophages (phages), with their high specificity, self-amplification, and eco-friendly nature, have re-emerged as promising candidates for sustainable plant disease management. This review evaluates systematically current knowledge on phage-mediated suppression of bacterial phytopathogens and the ways in which abiotic stresses influence their stability, persistence, and field performance. Evidence shows that phages exert disease control through direct mechanisms, such as lytic infection of host bacteria, disruption of biofilm and interference with quorum sensing, as well as indirect mechanisms such as synergistic interactions with beneficial microbes, modulation of plant immune responses and reshaping of microbial community dynamics. Despite these strengths, abiotic stresses pose significant barriers by reducing phage infectivity through desiccation, UV exposure and fluctuating temperatures, while also complicating delivery and consistency in complex agroecosystems. Advances in formulation technologies, such as polymer-based coatings, encapsulation and nanocarrier systems, are being developed to enhance phage survival under stress conditions and extend their field applicability. Concurrently, ecological safety, biosafety regulations, and the risk of unintended shifts in microbial communities remain important considerations for their deployment in large-scale. By integrating recent experimental findings, this review identifies key gaps and highlights strategies to improve effectiveness and resilience, making phage therapy as a potential cornerstone of climate-smart, sustainable plant disease management. Ultimately, progress will depend on combining phage therapy with multi-omics insights, beneficial microbial consortia, and precision agriculture tools to optimize outcomes under the multiple abiotic stresses faced in modern crop production.