Viral vectors for antimicrobial peptide expression: a new path for crop protection

Antimicrobial peptides (AMPs) are key components of plant innate immunity, offering broad spectrum protection against pathogens and represent promising alternatives to chemical pesticides for sustainable crop protection. Despite their broad range antimicrobial activity and low potential for resistance development, the deployment of AMPs in agriculture has been severely limited by instability, poor bioavailability and the lack of efficient, field-compatible delivery strategies. Harnessing viral vectors as platforms for AMP expression in plants represents a powerful strategy to enhance plant innate immunity. This review provides an overview of the potential of viral vectors for transient gene expression, functional genomics and genome editing. We discuss the design, construction and delivery of viral vectors, as well as the main challenges associated with AMP expression, including cytotoxicity and stability. Finally, inspired by adeno-associated virus (AAV) mediated AMP delivery strategies in mammals, we propose a vaccine-like strategy for plant protection, in which viral vectors enable endogenous AMP production Although plants lack adaptive immunity, virus-mediated AMP expression may function as a biochemical analog, reinforcing basal defence layers and enhancing tolerance to pathogen infection. By integrating viral biotechnology with plant defence mechanisms, this approach could redefine the future of sustainable agriculture.