“Role of chitosan nanoparticles in sustainable plant disease management”

Plant diseases pose a significant threat to global food security, necessitating innovative and sustainable strategies for disease management. Due to its numerous emerging and innovative applications, nanotechnology has garnered interest in a variety of sectors. Engineered nanoparticles are versatile materials with sizes ranging from 1 to 100 nm that can be used as fungicides, bactericides, and nano-fertilizers because of their high reactivity, wide surface area, and tiny size. In order to achieve the goals of sustainable farming, nano-bioformulations are being developed. Biopolymers, including cellulose, starch, alginate, chitin, and chitosan, with ecological endurability are employed for synthesizing nano-formulations. The second most prevalent biopolymer after cellulose is chitosan, which is utilized extensively because of its special qualities, which include non-toxicity, pH sensitivity, abundance, biodegradability, biocompatibility, low allergenicity, and bioabsorbability. Chitosan, a natural biopolymer derived from chitin, has gained attention for its antifungal, antibacterial, and elicitor properties. The combination of natural biopolymers with nanotechnology presents an opportunity to revolutionize agriculture and plant protection. High surface area, positive charge, and nanoscale size are some of the distinct physicochemical characteristics of nano-chitosan that boost its bioactivity and improve the interaction with plant tissues. Chitosan nanoparticles (ChNPs) have multifaceted modes of action, viz., direct antimicrobial activity, induction of plant defense, and modulation of microbial gene expression. It is broadly used in disease suppression and improving overall plant health. The techniques, viz., ionic gelation, emulsion cross-linking, and solvent evaporation, are commonly used to synthesize ChNPs, showing better control over particle size, stability, and biocompatibility. The present review highlights the synthesis of ChNPs, their potential applications in crop protection, their mechanism of action against plant pathogens, and their toxicity in plants.