What harm does grape felt disease have? What are the prevention and control techniques?

Grape felt disease is actually caused by a pest, rust tick, and its symptoms are similar to diseases, so people are used to being included in the category of diseases. So specifically, what is the harm of grape felt disease? What are the prevention and control techniques?

What is the harm of grape felt disease?

1. Hazard characteristics

According to the investigation, the insect is mainly harmful to grape leaves, which begins to spread in spring and can continue to damage to defoliation. The main damage: after the leaf was killed, the irregular pale disease spot occurred on the back of the leaf at first, the shape was irregular and the size was different, the diameter of the disease spot was about 2~10mm, and then the leaf surface formed bubble-like protuberance, dense felt-like villi, like felt, hence the name. The villi gradually changed from white to brown, and finally to dark brown.

When the damage is serious, the leaf shrinks, the texture thickens and hardens, and the leaf surface is uneven, sometimes dry and broken, often causing early defoliation.

When it is serious, it can also harm tender shoots, young fruits, tendrils, pedicels and so on. The leaf shrinkage of the damaged plant seriously affects leaf photosynthesis, so the growth of branches is weak, the ear is small, the grain is small, the yield is reduced, and the quality becomes bad, which often results in early defoliation, which not only affects the yield of the current year, but also weakens the tree potential and affects the differentiation of flower buds. Therefore, it also affects the yield and quality of the second year.

2. Occurrence regularity

Grape felt disease occurs for three generations a year in Turpan. It began to occur in mid-late April and seriously damaged in mid-late May and September. The high temperature and drought weather in Turpan in summer is beneficial to its growth and development, so it can be harmful to grape in the whole growing season. The female adult mites began to lay eggs in the first and middle of April and overwintered in the hairs of bud scales and the seams of branches and vines in the middle of October, with the largest number of insects in the lower part of branches and annual shoots and bud scales.

The grape began to sprout in the following spring. I migrated to the back of the tender leaves to absorb nutrients. The felt was formed by the hypertrophy and deformation of the upper epidermis of grapes stimulated by gall mites, which had a protective effect on gall mites.

Second, what are the prevention and control techniques of grape felt disease?

1. Select disease-free seedlings

Felt disease can be spread with seedlings or cuttings, and it is best not to introduce seedlings from the disease area. When it is necessary to introduce seedlings from the disease area, disinfection must be carried out before planting, and a relatively simple method is to soak in hot water. The method is to soak the seedlings or cuttings in 30: 40 ℃ warm water to soak 3~5min, and then move to 50 ℃ warm water to soak 5~7min to kill the rust tick lice lurking in the bud.

2. Strengthen the management of fertilizer and water

Increase the application of organic fertilizer, control the amount of nitrogen fertilizer, reasonable irrigation, improve the resistance of grape itself.

3. Strengthen the tree management.

When the grape opens the mound, it is necessary to ensure that the grape branches will not be damaged. Otherwise, it is easy to invade a variety of germs from the wound. Remove the old skin from the stem vines to increase the mortality of overwintering pests under the skin.

4. Chemical control

After sprouting, before and after leaf expansion, the early spring grapes were sprayed with crystal stone sulfur mixture of 100-150 times as much as 45% when the twigs grew 13~15cm, respectively, in order to kill the overwintering adults. 0.3% washing powder could be added to the solution to improve the spraying effect. (note: spray must be comprehensive and thoughtful. The leaves of grape vines must be sprayed until they are wet; do not spray when the temperature is above 28 ℃. Otherwise, it is easy to cause drug damage.

After the grape leaves are unfolded, if the damaged leaves are found, they should be removed and buried or burned immediately. Acaricides such as 1000-fold solution of Lexben, 1000-fold solution of Emicidone or 2000-fold solution of Amijing were used.