Effect of chitosan application on some secondary plant metabolites in chili

The use of the chitosan elicitor has alleviated biotic and abiotic stress. Chitosan is particularly effective in inducing phytochemical properties such as phenolic compounds and flavonoids. Chili is an excellent source of carotenoid and flavonoids. The aim of this study is to determine the effect of chitosan on some secondary plant metabolites in chili. Chitosan at 0, 60, 120 and 240 mg L^‑1 were sprayed once a week after transplanting until harvest. Mature fruits were harvest at 45 days after anthesis and analyzed for secondary plant metabolites, including total phenolic compounds, total flavonoid, salicylic acid, carotenoid content and DPPH radical scavenging. Results showed that chitosan application at 120 mg L^‑1 increased total phenolic, total flavonoid, salicylic acid, carotenoid content and DPPH radical scavenging by 2.37-4.90, 1.11, 1.19-1.41, 2- and 1.05-1.72 folds, respectively. However, chitosan at a concentration of 240 mg L^‑1 reduced all secondary plant metabolites. Results of this study supported the application of chitosan at 120 mg L^‑1 to produced good quality chili.