Chitosan and Changes in Gene Expression During Fruit–Pathogen Interaction at Postharvest Stage

Summary Chitosan is a natural, biodegradable, and nontoxic compound with fungicidal properties and it also induces defense mechanisms in fruit tissues during the postharvest period. Reports so far indicate alterations at the microscopic, biochemical, and molecular level in plant system tissues and the pathogens that attack them, causing changes in the structure and cell metabolism due to its polycationic activity. There is little information on the effect of chitosan on gene expression in fruits; however, preliminary unpublished data from transcriptomic analysis of the chitosan–Colletotrichum–avocado cv. Hass interaction indicate significant changes in the gene expression of the pathogen and host.