Common diseases and pests of heavy fan and their control methods

Common diseases of heavy fans: leaf blight

Basic symptoms of severe fan leaf blight: Leaf blight mostly infects leaf margins and leaf tips. The lesions are irregular in shape, ranging from small to large, and are reddish-brown to gray-brown. The lesions are connected into large dead spots, and the dry area reaches 1/3-1/2 of the leaf. There is a darker band on the edge of the lesions; the boundary between the diseased and healthy spots is obvious. In the later stage, some small black spots appear on the lesions.

Causes of leaf blight: poor ventilation, high temperature and humidity, poor plant growth, etc.

Prevention and control measures for severe fan leaf blight: thoroughly remove diseased leaves and burn them in a concentrated area; for spraying pesticides, you can choose 50% thiophanate-methyl 500-800 times diluted, and spray once every ten days.

Common pests of heavy fan: scale insects

Basic symptoms of double-fan scale insects: Scale insects attach to the surface of double-fan leaves, and their secretions contaminate the leaves, even causing serious consequences such as leaf withering.

The cause of the occurrence of heavy fan scale insects: untimely disinfection and the breeding of insect eggs.

Control measures for heavy fan scale insect: Spray the pesticide in time during the nymph stage. You can use 1000 times diluted 40% omethoate, spray once every 8 days, for 2 to 3 times in a row. Mixing white wine with water can also effectively kill scale insects without damaging the heavy fan leaves.