How to prevent and cure red leaf spot of Zhu Ding?

If Zhu Dinghong is not properly maintained, leaf spot disease will occur easily in late autumn and early winter, and leaf tip, leaf surface and leaf edge will get sick. Small purple-brown spots appeared on the leaves in the early stage of the disease, which would expand into brown and irregular spots, then mottled withered yellow, and finally grayish white, with conidia of black punctate pathogens scattered above. The prevention and control methods are as follows:

1. Clear the diseased leaves. Diseased leaves should not be completely removed in winter to reduce the source of infection in the following year.

2. Chemical spraying. During the onset of the disease, 800 times carbendazim solution was sprayed in time for several times.

3. Pay attention to maintenance. Usually pay attention to ventilation and maintenance to make the plant grow strong and increase the ability to resist disease.

Control methods of red insect disease:

1. Red spider

The red spider mainly harms the leaves of Zhu Dinghong, sucking juice, making the leaves show gray-yellow spots or patches, and the leaves are orange and shedding. Solution: spray with 1000 times of dicofol EC.

2. Nematodes

Mainly from the stomata on the leaves and stems invaded, caused by the invasion of leaves and stem flowers, and gradually spread to the direction of the bulb. Solution: the bulb can be soaked in 43 ℃ warm water and 0.5% formalin for 3-4 hours to achieve the control effect.

3. Longicorn beetles

The chrysanthemum longicorn beetle mainly bites the stem when the adult lays eggs, the stem tip above the wound withered, and the larva eats the stem and root, resulting in the death of the whole plant.

Solution: cut off the withered and drooping shoots in time, eliminate the eggs and larvae, and spray 500,800 times of trichlorfon or fenvalerate, 2500 times of fenvalerate and 25% of Yuanke No. 3.

4. Bran cutlet scale

The main reason is that the adults suck the juice of Zhu Dinghong, which causes the leaves to fall early and the branches to die, which affects the flowering. Solution: when a large number of worms are found, the worms can be scraped off and sprayed with 1000 times liquid of 90% trichlorfon or 1500 times liquid of 50% Daofeng Powder, once every 15 days, 2 times in succession.

5. Virus disease

It mainly harms the roots and leaves of Zhu Dinghong, causing the roots and leaves of Zhu Dinghong to rot. Solution: the disease can be sprayed with 75% chlorothalonil miscible powder 700 times.

6. Leaf spot

After the invasion of leaf spot, the leaf tip, leaf edge and leaf surface all formed purple-brown dots, and gradually expanded the brown-red oval or irregular disease spots. Solution: during the onset of the disease, carbendazim was sprayed with 600 × 800 times of carbendazim for 3 consecutive 4 times.

The red flower of Zhu Ding is beautiful in color, which is of great ornamental value, and it is a good embellishment to decorate it at home, but we should pay attention to the prevention and control of red insect disease, which is what we must understand to raise it well.