Postharvest Chitosan Treatment Induces Resistance in Potato Against Fusarium sulphureum

The effects of chitosan treatment and inoculation on dry rot in tubers and slices of potato were studied. The results showed that chitosan treatment significantly reduced the lesion diameter of potato inoculated with Fusarium sulphureum. The treatment at 0.25% showed the best effect. Chitosan at 0.25% increased the activities of peroxidase and polyphenoloxidase,and the contents of flavonoid compounds and lignin in tissues. Increased activities of β-1,3-glucanase,and phenylalanine ammonialyase were observed,but there were no significant differences between the treated and the control. These findings suggested that the effects of chitosan could be associated with the induced resistance against Fusarium dry rot in potato.