Effect of Composite Coating Film of Chitosan and Nanometer ZnO on the Resistance of Black Spot Disease of Winter Jujube
In order to study the anti-disease effect and mechanism of the composite coating film of nano ZnO and chitosan(CTS)with different particle sizes on the black spot disease of post-harvest winter jujube,fresh winter jujube was subjected to coating treatments,and then inoculated with Altrenaria alternata.By determining the changes in fruit quality indexes,content of disease-resistant substances,and activities of disease-resistant related enzymes of winter jujube,we explored the optimal particle size of nano-ZnO for suppressing the black spot disease at the same concentration of CTS.The results showed that the composite coating treatment of nano-ZnO and CTS could delay the expansion of the diameter of the fruit spot of winter jujube,inhibit the rise of respiratory intensity,and reduce the rate of weight loss and spoilage.Moreover,the composite coating treatment of nano-ZnO and CTS could inhibit the decrease of the content of polyphenols,flavonoids and other antioxidant substances,and improve the reducing power and the scavenging ability of DPPH radicals in winter jujube,and it could also increase the activities of superoxide dismutase,catalase and ascorbate peroxidase activities,of which the 0.2%≤100 nm nano ZnO composite 1%CTS treatment group had the best experimental effect.Therefore,it was believed that the composite coating treatment of nano-ZnO and CTS maintained the stabilization of fruit cell membrane structure by inducing the activities of disease-resistance-related enzymes,which in turn enhanced the disease resistance of jujube after harvesting,thus delaying the occurrence of black spot disease.
万方数据
维普
