Effect of chitosan on antioxidant contents and resistance of rice blast disease in sung yod phatthalung rice

Abstract

This research was aimed to study the effect of chitosan on total polyphenol contents, anthocyanin contents, antiradical properties and resistance of rice blast disease in Sung Yod Phatthalung rice (Oryza sativar L.) cultivars. The chitosan was applied on rice leaves at concentrations of 50, 100 and 500 ppm compared with the control (without the chitosan and only adding a 0.025% acetic acid, respectively). The result showed that 500 ppm of chitosan could significantly increase the total polyphenol contents (220.75 mg GAE/100 g dry weight sample), anthocyanin contents (2.98 mg/100 g dry weight sample) and antiradical properties (83.15%) in the grain extracts of Sung Yod Phatthalung rice. In addition, Necrosis test on rice leaves treated with 500 ppm of chitosans clearly indicated the plant resistance againt Pyricularia grisea. Therefore, the future studies of chitosan activation mechanism will give more valuable information that possible to be applied in the healthy rice product development and fungal disease control.