Symptoms and Control Methods of Polygonatum Leaf Spot Disease
The disease begins in April to May. On affected leaves, elliptical or irregular lesions first appear at the leaf tip, with brownish outer edges and pale white centers; the disease spreads downward from the lesions, causing the leaves to wither and die. The disease is more severe during the rainy season. Control methods: 1) After harvest, clean the field and garden, gather the dead branches and diseased plant debris and burn them to eliminate the overwintering pathogen. 2) Before the disease occurs and in the early stages, spray 1:1:100 Bordeaux mixture, or 50% Tuzet (thiram) 1000x solution, once every 7 to 10 days, for 3 to 4 consecutive sprays.
The disease begins in April to May. On affected leaves, elliptical or irregular lesions first appear at the leaf tip, with brownish outer edges and pale white centers; the disease spreads downward from the lesions, causing the leaves to wither and die. The disease is more severe during the rainy season.
Control methods:
1) After harvest, clean the field and garden, gather the dead branches and diseased plant debris and burn them to eliminate the overwintering pathogen.
2) Before the disease occurs and in the early stages, spray 1:1:100 Bordeaux mixture, or 50% Tuzet (thiram) 1000x solution, once every 7 to 10 days, for 3 to 4 consecutive sprays.