How to prevent and control chrysanthemum rust? Triazole fungicides can be used
Chrysanthemum rust mainly damages the leaves, and can also damage the stems. At the beginning of the disease, pale yellow spots appear on the underside of the leaves, along with raised light brown or rust-colored blister-like structures; pale yellow spots appear on the upper leaf surface, slightly sunken, and soon the blister-like protrusions crack open and release yellow-brown powder. Warm and high humidity favors the disease. During the rainy season in April-May and the rainy weather in late autumn...
Chrysanthemum rust mainly damages the leaves, and can also damage the stems. At the beginning of the disease, pale yellow spots appear on the underside of the leaves, along with raised light brown or rust-colored blister-like structures; pale yellow spots appear on the upper leaf surface, slightly sunken, and soon the blister-like protrusions crack open and release yellow-brown powder. Warm and high humidity favors the disease. In the rainy season in April-May and the rainy weather in late autumn, the disease is more severe.
Before the disease occurs, regularly spray with 80% zineb 500-700 times dilution to prevent the disease from occurring. In the early stage of the disease, before the lesions rupture, you can alternately use 15% triadimefon wettable powder 1500 times dilution, 20% carboxin emulsifiable concentrate 400 times dilution, 25% metalaxyl wettable powder 800 times dilution, 5% metalaxyl-copper wettable powder 600 times dilution, 75% chlorothalonil wettable powder 500 times dilution for spraying, once every 7-10 days, for 3-4 consecutive treatments; or spray with 2.5% diniconazole emulsifiable concentrate 4000 times dilution, once every 20 days, for 2-3 consecutive treatments. While using chemical control, diseased leaves should also be removed or diseased plants pulled up and burned.