1. Symptoms: mainly harmful to the leaves of Dracaena fragrans. The shape of the spots is different, slightly raised, and the spots are yellow to purple brown. When the disease is serious, the leaves will wither and droop.
2. Prevention and control method: if any disease is found, it shall be removed in time, and the plants shall be sprayed with Benazolin or chlorothalonil for treatment. Spray once every 10 days or so, and spray 2-3 times continuously to cure.
1. Symptoms: in the early stage of the disease, small yellow spots appeared at the tip and edge of the leaves, and gradually changed into big red brown spots with different shapes. In the late stage of the disease, the center of the lesion became brown or gray white, and the edge of the lesion was dark brown. When the disease is serious, it will cause the whole leaf to dry and rot.
2. Prevention and treatment method: spray 50% zuibake, shibaogong wettable powder 1000 times or 25% carbofuran wettable powder 500 times in the early stage of the disease. Spray once every 7-10 days.
1. Symptoms: the larvae will eat up and down in the cortex of the wood column. When the wood column is light, there will be insect passages in the stem, and a small amount of insect excrement will be discharged. When the skin is heavy, the fleshy part will be eaten up, which is full of fecal debris, and there are many vent holes that bite the epidermis. Finally, the branches and leaves will gradually wilt and yellow, causing the whole plant to die.
2. Control method: peel off the epidermis of the injured part in time, clean up the dung and kill the larvae. At the same time, spray the diseased plant with 1000 times of 40% Omethoate emulsion once a week and three times continuously. After that, dichlorvos can be used to spray the stem of the diseased plant, and then plastic film can be used to wrap and seal it for 5 hours to further kill the bagasse moth.
