Common diseases and pests of holly and their control

Common diseases of holly

Leaf spot

The symptoms are gray-brown spots on holly leaves, which are mostly round or oval. When the humidity is high, a gray-white mold layer grows on the surface of the diseased parts. The prevention and control measures are as follows:

Remove and burn diseased leaves promptly to reduce the source of infection; apply oak leaves or cottonseed powder to the soil; spray plants with copper preparations such as Bordeaux mixture or fungicides such as ferbam for prevention and control, and spray with 600 times diluted 75% thiophanate-methyl wettable powder.

Blight

The disease causes the bark of holly branches to turn brown, large leaves to dry up and fall off, and the plant dies because it cannot obtain nutrients. The symptoms of this disease are extremely similar to the death of plants due to dehydration. Careful to distinguish them and detect the disease in time. Once symptoms occur, they are often quite serious and relatively difficult to prevent and treat, so prevention is generally the main approach. Specific prevention and control methods are as follows:

① Immediately after pruning, spray 800 times diluted New Posture WP and 1000 times diluted Amidoxan to prevent pathogens from invading through the wound;

② Spray the fungicide once every 10 days with 600 times diluted Bacterial Aseptic or 600 times diluted Xinziqing wettable powder, and spray three times in a row.

Root rot

You can spray 10% antibacterial agent 401 acetic acid solution 1000 times diluted.

Common Pests of Holly

To prevent pests, we must first choose healthy holly seedlings for planting. The planting density should be appropriate and attention should be paid to ventilation, etc.

For aphids, leafhoppers and scale insects, you can spray 1000 times diluted 50% cypermethrin emulsifiable concentrate. When red spider mites occur, you can spray them with 1000 times diluted 20% trichlorosulfonyl wettable powder.