Symptoms: most of them occur in summer. From the first ten days of June, the bark begins to appear. From the first ten days of July, the outside of the bark begins to change color gradually, leading to ulceration and affecting the health.
Prevention and treatment: this disease is very hidden. After infection, it can not be shown immediately. We need to start from the source of prevention and control. When pruning in winter, we need to cut off the diseased branches and dead branches, burn them intensively, and add suitable fertilizer. After the disease is found, the necrotic tissue on the bark can be scraped off first and then sprayed with 50% fungicide 50 fold solution.
Symptoms: the disease spots appear from the lower leaves, which are small yellow brown dots at the beginning, then gradually expand, yellow halos appear on the periphery, and dark brown or dark brown mold will appear on the disease spots.
Prevention and control: when the disease is found, you can use tobujin, stone sulfur mixture and other chemicals for prevention and control, the effect is also very good.
Symptom: Scarab is a kind of pest that mainly damages the stem and leaf of the plant. In the later stage, the plant will be incomplete.
Prevention and control: spray a little Omethoate solution and then loosen the soil.
