What are the dangers of tea yellow mite to winter melon? What pesticides can be used to control tea

For prevention, it is recommended to dilute avermectin 2000 times once a month or so. Do not use it often. About three points poisonous.

Generally, avermectin is also used for about three seasons. When spraying, spray evenly, but also spray the back of plant leaves and soil. You can also use Dedabilin, Jin Wanzhi, Domineering Ridge, etc.

Spray according to the directions for use. In addition, it is necessary to deal with weeds in the crop field and keep the crop environment as clean and tidy as possible. Methane and infrared also have a certain killing effect on the subyellow mite, the pests and diseases are greater than **, the loss must be, and many farmers and friends should prevent it in advance as much as possible, so as not to affect the yield and taste of tea.

Hope to help this friend.

The body of the sex mite is ovate, millimeters long, light yellow to orange, translucent, shiny. Four pairs of feet with a white strap on the back. The end of the abdomen of the female is flat, and the end of the abdomen of the male is conical.

ovate, about millimeters long, gray and white, transparent. The oval surface has 5-6 rows of longitudinal protrusions. The pups are oval, milky white, with three pairs of legs, a white band on the dorsal back of the body, and a bristle at the end of the abdomen.

Rhomboids and translucency are the stages of temporary cessation of development, surrounded by the epidermis of young mites. Tea yellow mites can breed up to their 20s a year and can live all year round in sheds. Polyyellow mites are mainly hermaphroditic and can also reproduce with high cancer, but the albuminization rate is low.

Females scatter eggs on the back of watermelon leaves, in avocados, or in buds. Females live up to 17 days, a minimum of 4 days, and an average of days. The development period is different at different temperatures.

A warm and humid environment contributes to the occurrence of tea yellow mites, so it is more likely to occur when growing watermelons in a membrane chamber. Tea is mainly spread by creeping and wind, and can be spread inside the warehouse through field management, clothing, farming tools, etc.

The growth point is wilted, the leaf edge is curled back, and the leaf is shiny behind the leaf, the harmful symptoms of the hypoxanthus mite are very similar to those of the viral disease, but the main difference is that in the painting above, there is no streamer on the back of the viral diseased leaf, and in another case, if there are no totally poisonous insects, etc., it will not be detailed here. There are many ways to prevent **, these can be found in the data, we sprayed avermectin 2000 times twice, and the effect was obvious one week apart. After three days of spraying, observing the appearance of the green pepper plant, it can be found that the side buds are significantly released, and the performance is good after one week of spraying, and the performance is better after one month of spraying.

After the injection of the drug, the growth points in the upper part are rarely present, and the growth points on the axillary side of the leaf are more. The plant population can be reconstructed by pruning to remove the upper part.

The calendar time of the generations of the subyellow mite is very short. The warm and humid environment favors its series and occurrence. The room temperature is suitable, and it can happen all year round.

From mid to late June to mid-September, it is time for an erection. Mainly hermaphroditic, poisonous female reproduction can also be carried out, and most of the eggs of Hypoxanthus are laid on the back of young leaves and in the hollows of fresh fruits.

The affected leaves are thickened and stiff, smaller or narrower, yellowish brown or grayish brown on the back of the leaves, with an oily sheen, and the leaf margins curl to the back. The young stems turn yellowish-brown and twist into a whorl-like shape. The flower buds are damaged and deformed, and the heavy ones cannot bloom and set fruits.

Weeds on the edge of the field and litter in the field, level the land, destroy the wintering site, and eliminate the source of wintering insects. If this mite is found, it should be immediately controlled, field management should be strengthened, and strong seedlings and seedlings should be cultivated. Appropriately increase the amount of ventilation and light transmittance, prevent overgrowth and crazy growth, effectively reduce the relative humidity of the air in the field, ecologically break the climatic law of the occurrence of tea yellow mites, and reduce the degree of harm.

Do a good job in winter prevention and control, eradicate weeds in the field, remove dead branches and fallen leaves in time after vegetable harvesting, and burn them in a concentrated manner, so as to reduce the source of overwintering insects. When applying pesticides, attention should be paid to spraying the solution on the back of young leaves, young stems, flowers and young fruits on the upper part of the plant.

In general, the yellow mite of eggplant tea causes the original color of the eggplant to disappear and gradually turn dark yellow-brown. The surface of the eggplant fruit will harden, and with the continuous growth of the eggplant, the fruit will crack, affecting the yield of the eggplant. When the eggplant is harmed by the tea yellow mite, the leaf edge of the eggplant will curl downward.

The back of the eggplant leaves will be brown, and the new buds will also be harmed by the tea yellow mites, and the growth and development of the eggplant will decline significantly. Under the environmental conditions of suitable temperature, weak sunshine and continuous rain, it is easy to produce diseases, and will spread its diseases through wind and rain and artificial irrigation. It can effectively reduce the relative humidity of the air between eggplants, and can reduce the harm of yellow mites in eggplant tea; After eggplant sowing, high-quality and well-rotted organic fertilizer was applied in time, and nitrogen, phosphorus and potassium fertilizers were applied at the same time, and drainage was strengthened after rain. Agricultural personnel timely weeds and leaf litter between eggplant to effectively reduce the harm of insect sources between eggplant plants.

Plants that are found to be diseased in eggplant should be uprooted in time, taken away from the planting area and destroyed; When the rate of eggplant leaf curling reaches the rate, it should be sprayed in time to control. Or spray pesticides on the young leaves and young fruits of eggplant plants in time, and spray 3000 times of emulsifiable concentrate with fenoxin (avermectin, aifudin, etc.), and spray every 7-10 days; 20% compound liuyangmycin EC 1000 times liquid spray, sprayed every 7 days; 73% gram mite emulsifiable concentrate 2500 times liquid spray, sprayed every 7 days, can effectively control eggplant tea yellow mites.

Of course, it will cause a decrease in the yield of loofah. When the loofah is flowering, it is necessary to spray the corresponding pesticides to prevent the appearance of tea yellow mites and pests in the loofah, and prevent them in advance?

It will cause a decrease in the yield of loofah, mainly harm the young tissues on the plant, and will lead to stunted crop growth, flower and fruit drop. Choose drugs that can kill eggs and insects at the same time for control, and generally need to be sprayed several times in a row, about once a week.

Because the body of the tea yellow mite is very small and not easy to detect, the early investigation needs to be judged according to the damaged plant. After planting and slowing down the seedlings, the vegetables in the protected area should be investigated and treated in time when it is found that individual plants have symptoms of damage, so as to prevent further expansion and spread. The peak period of yellow mites in spring and autumn tea needs to be treated regularly with an interval of 7 to 10 days.

The focus of spraying is mainly on the young leaves, young stems, flowers and young fruits on the upper part of the plant, and pay attention to the rotation of medicine.

Characteristics of tea yellow mites: adult mites and young mites are concentrated in the young part of the crop to suck and suck, the back of the affected leaves is gray-brown or yellow-brown, with oily luster or oil-stained, and the edge of the leaf is curled downward. The affected young stems and shoots turn yellow-brown, twisted and deformed, and the top of the plant is dry in severe cases.

The damaged buds and flowers cannot bloom and set fruit in the most serious cases; The fruit is damaged, the fruit stalk, sepal and peel turn yellow-brown, lose luster, and the wood is corked, which eventually leads to the eggplant cracking, which is in the shape of flowering steamed buns, bitter and astringent, and inedible.

Those who were seriously affected by green peppers lost leaves, flowers and fruits, and the yield was greatly reduced. The leaves of the affected tomato become narrow, stiff and erect, shrunken or twisted and deformed, and finally bald. Due to the small size of the mite, it is difficult to see and identify with the naked eye, and these characteristics are often mistaken for physiological or viral diseases.

1) Agricultural control.

Clean the countryside. Eradicate weeds in the field in time, remove dead branches and fallen leaves in time after vegetable harvest, concentrate on burning, and strengthen the prevention and control of autumn and winter vegetables and tea yellow mites, which can reduce some insect sources. Cultivating clean seedlings.

The north should do a good job in the prevention and control of seedling greenhouses in autumn and winter, and avoid bringing mites from seedling greenhouses into production greenhouses or greenhouses and other protected areas. At the same time, attention should be paid to removing weeds and residues inside and outside the greenhouse, and paying close attention to the prevention and control in the greenhouse and other protected areas to reduce the source of mites moving into the open field.

2) Biological control.

At present, the natural enemies available for the control of tea yellow mite include Blunt Nissini, Blunt T. deli, Tonorium longiflora and P. parviflora.

3) Chemical control.

When the rate of leaf curling in the field reaches 2 3 heads (grains) per leaf, the average number of insects or eggs per leaf reaches 2 3 (grains) should be sprayed in time. The focus of the spraying is on the upper young part of the plant, especially the underside of the top few young leaves. Commonly used agents can be used 73% alkyne mite emulsifiable concentrate 1000 1200 times, 35% pyridoxine 1000 times, 20% pyridazine thionine 1000 times, 5% thiobenone emulsifiable concentrate 2000 times, etc., all of which have good control effects.

The prevention and control of tea yellow mite should be comprehensively used in agricultural control, biological control and pesticide control measures, and timely treatment should be selected and treated when the spot occurs.

1) Do a good job in the prevention and control of winter nurseries and production greenhouses, eradicate weeds around sheds and rooms, remove dead branches and leaves in a timely and thorough manner after harvesting, and eliminate the source of overwintering insects.

2) Cultivating insect-free seedlings. Before transplanting, the seedlings were comprehensively controlled with pesticides.

3) The available natural enemies of the tea mite include Nissini blunt mites, De's blunt mites, tumorous long-bearded mites and small flower bugs.

4) When it is necessary to carry out chemical control, it is necessary to pay attention to the selection of pesticides with low lethality to natural enemies, and pay attention to the rotation of different types of pesticides to avoid harming natural enemies and causing pest mites to develop resistance.

Prevention and control methods: Agricultural control: try to eliminate the tea yellow mite in the protected area and clean the field to reduce the damage on the open field vegetables in the following year.

Cultivating mite-free seedlings: spraying pesticides to kill mites before planting, and early maturing varieties can be selected, planting early and harvesting early to avoid the peak of pest mites. Pharmaceutical prevention and control:

In the early stage of the occurrence of the following agents for spraying, generally every 7 10 days spray 1 time, spray 2 3 times, spray all parts of the spray, especially the growth point, the back of young leaves, young stems, flowers and young fruits. You can choose 20% dicofol, 25% quinthion EC, 20% pyridazion 1500 times EC, or 5% Nisolan EC, 50% tricyclic tin wettable powder or kill (21% synergistic cyanoma EC).3000 times of 5% Uranus (bifenthrin) emulsifiable concentrate, or 1000 times of 73% alkyne mite emulsifiable concentrate, or 1000 1500 times of 25% acaricide wettable powder, or 1500 2000 times of 40% cycloprofenofol wettable powder, or 1000 times of 20% compound liuyangmycin.

Tea yellow mites, also known as tea young leaf mites, tarsal mites. The eggs are scattered on the back of young leaves, the recesses of young fruits or young buds, hatched after 2 3 days, the young mite period is about 2 3 days, and the mite period is 2 3 days. The optimal temperature for development and reproduction is 16 23 and the relative humidity is 80% 90%.

The duration of generational development is 28 30 days, which is 4 5 days; In 18 to 20, for 7 to 10 days. Adult mites are lively, have strong tenderness, eggs and young mites have high requirements for humidity, and can only develop when the relative humidity is above 80%, so the warm and humid environment is conducive to the occurrence of tea yellow mites. Due to the continuous expansion of the cultivation area of the protected area, the tea yellow mite can occur all year round in the middle and lower reaches of the Yangtze River, and the reproductive ability of the tea yellow mite in winter is low.

In the greenhouse, the damage starts in late April, and the peak season is from late June to mid-September, and the winter is mainly overwintered in the greenhouse.

Tea yellow mite mainly harms eggplant, tomato, cowpea, kidney bean, green pepper, etc., and eggplant and pepper are the most serious. The juice is usually sucked by adult mites and mites concentrated in the tender part of the eggplant or pepper. The symptoms of tea mite damage on the back of the leaf are obvious, which is reflected in the curl of the affected leaf to the back of the leaf, and the mesophyll is oily pink, which has brownish-yellow or brown dots, and the leaf or young stem is twisted and deformed in severe cases; Tea mite mostly occurs in leaf tips, with the main damage site of 3 4 leaves below the growth point.

When the fruit is harmed, yellow-brown pinhole-like spots are formed on the surface of the fruit stalk, peel and sepals, and the fruit loses its luster, stiffness and cork, which seriously affects the edible value.

Control methods: The control of tea yellow mite is relatively simple, but due to the short life cycle and fast reproduction of tea yellow mite, special attention should be paid to early control. 2,4-D pesticide damage and thrips damage also have similar symptoms (leaf curling) to tea mite damage, but they can be distinguished from the damaged parts, the color of the affected leaves, and the main oil stain.

Pesticide control is controlled once every 7 10 days, and applied 3 times as appropriate, which can control the hazard. It can be used 2000 3000 times of insect mite light emulsifiable concentrate, or 20% mite net 2500 4000 times, or 40% tachycarnone 4000 4500 times, or 73% gite emulsifiable concentrate 2000 times, or 5% nisolan emulsifiable concentrate 2000 times, 1% insecticide 2000 times liquid, 20% metformamidine emulsifiable concentrate 1000 times liquid, 21% killing emulsifiable concentrate 2000 times liquid, Uranus emulsifiable concentrate 3000 times liquid spray. In addition, plant residues and weeds should be removed in time in winter to reduce the source of overwintering insects.

1) Harmful characteristics Adult mites and young mites gather in the young parts of the plant (such as growth points, new leaves, flower buds and fruits) to suck the sap, causing deformity of the damaged plant, such as leaf rolling, leaf shrinkage and leaf thickening and stiffness, making the back of the leaf yellow-brown, and the leaf has oil-soaked luster. When the flower bud is damaged, it forms a deformed flower. After the young stems are damaged, they turn yellowish-brown and twist and deform, so that they dry up and bald.

If the young melon is damaged, it is stiff and deformed, and it cannot develop normally.

2) prevention and control methods 73% gram mite emulsifiable concentrate 2000 times liquid, 25% mite exterminating mite wettable powder 1000 times liquid, killing 2000 times liquid, 10% Uranus emulsifiable concentrate 3000 times liquid, 20% exterminating 800 1000 times liquid, 3000 4000 times of eupsifiable concentrate of toss mite mite, 45% sulfur gum suspension 150 300 times liquid, Qi mite emulsifiable concentrate 3000 4000 times liquid, any one of the above agents, sprayed every 10 14 days, focusing on spraying the front of young leaves and stem ends, Squirt 3 times in a row.