Mechanism of Fungal Disease Management using Bioextracted Chitin Molecules: A Review

Groundnut (Arachis hypogaea L.) is an economically and nutritionally important legume widely cultivated in tropical and subtropical regions, including West Africa. However, its production is significantly constrained by fungal diseases that affect multiple plant parts and result in considerable losses in yield and quality. Existing disease management approaches, such as chemical-based strategies, present challenges related to environmental safety, sustainability, and pathogen resistance, underscoring the need for alternative control measures. Chitin and it’s deacetylated derivative, chitosan, have emerged as promising biopolymers for fungal disease management due to their biodegradability, biocompatibility, and broad-spectrum antifungal properties. Chitin, a structural polysaccharide found in fungal cell walls and crustacean shells, can be extracted through chemical or biological processes, while chitosan exhibits enhanced bioactivity owing to its cationic nature. These compounds exert antifungal effects through multiple mechanisms, including disruption of fungal cell wall integrity, inhibition of spore germination and mycelial growth, chelation of essential nutrients, and stimulation of host defence responses. In addition, chitin-based substrates promote the activity of beneficial chitinolytic microorganisms, thereby enhancing biological control. In agricultural applications, chitin and chitosan demonstrate potential as eco-friendly disease management tools through their use as biopesticides, soil amendments, and post-harvest protective agents. Their multifunctional properties and low environmental impact position them as sustainable alternatives or complements to conventional fungicides. Integrating chitin and chitosan-based strategies into groundnut disease management systems may contribute to improved crop health, productivity, and long-term food security.