During the growth process of peach trees, their branches, trunks and fruits will be harmed by different degrees of pests and diseases. Peach root cancer causes the roots and stems of peach trees to form tumors and lignify, affecting the taste of fruits and harming peach trees. Peach gum disease mainly Occurs on branches, shoots, leaves, and fruits, causing the bark of the diseased branches to be rough, cracked, and difficult to heal. When the flow is serious, the tree is weak, and it is easy to become the spawning place of the pink-necked beetle and accelerate the peach. The tree died; the peach brown rot harmed the fruit and caused the surface to crack. When it was serious, the fruit became brown, rotted, and finally became a stiff fruit. Peach red-necked beetle and Hawthorn red spider are the main pests of peach trees, which damage the branches and leaves of peach trees, and seriously affect the yield of peach trees.

Peach trees, angiosperms. Rosaceae, a genus of genus, native to China, widely cultivated all over the world. Peach trees are hi-light species, with strong branching, fast growth, and fleshy and sweet taste. In addition to raw food, it can also be dried and canned. The fruit and leaves all contain almonds, and all the dried plants can be used as medicine. With the gradual warming of the early spring, various peach diseases and insect pests began to recover, breed and multiply. The early spring control of peach tree diseases and insect pests can effectively control the occurrence and spread of various diseases of peach trees and reduce the number of insect pests. The current situation of the occurrence and damage of the main pests and diseases of peach trees and their early spring prevention and control opinions are as follows:

1 Peach root cancer

1.1 Symptoms

It mainly occurs in the root and neck, and also occurs in the lateral root or root. The tumor is milky white or light red when it is formed. The surface is smooth and soft, then it turns brown. The tumor gradually becomes lignified and the surface is hard and rough. The probability that pathogens generally erode the roots of peach trees is much greater than that of roots, and the roots and stems have the greatest impact. The onset of peach trees is obviously poorly grown, the plants are relatively short, the obsolete yield is reduced and the taste is not good, and the whole plant will die seriously.

1.2 The law of onset

The pathogen is parasitic in the tissue of the cancer or in the nearby soil, and can be spread with rain or irrigation. The pathogen can inhibit the growth and reproduction of pathogenic bacteria mainly through the surface of the trunk and the alkaline environment of the peach tree. The probability of occurrence of heavy nursery or peach orchard is relatively large.

1.3 Prevention methods

(1) Nursery or orchard should try to avoid heavy planting. (2) Careful observation should be carried out during the growth of seedlings, and pests and diseases should be removed as much as possible; newly built orchards should strengthen quarantine and quarantine to prevent pests and diseases from entering. (3) Regularly check the orchard, and dig deep into the suspected diseased plants, confirm that the tumor is completely scraped off with a knife and disinfected with 1% sodium perchlorate or 0.1% liter of mercury solution; Immerse the roots (for diseased plants) or pour the roots (large trees). (4) The nursery uses soil to ensure no pathogenic bacteria and cultivate disease-free seedlings. (5) Strengthen soil management, rational fertilization, improve soil and enhance tree potential.

2 peach gum disease

2.1 symptoms

The diseased department sheds a translucent yellow gum, especially after the rain. When the oozing gum comes into contact with air, it turns reddish brown and is jelly-like. After drying, it turns into a red-brown to brown-brown hard rubber block. The diseased department is easily infected by saprophytic bacteria, causing the cortex and xylem to brown and rot, causing the tree to weaken, the leaves turn yellow and become smaller, and when severe, the branches or the whole plant die.

2.2 Causes

(1) Parasitic fungi and bacterial hazards, such as dry rot, rot, anthracnose, scab, bacterial perforation and fungal perforation, etc., these diseases or parasitic branches, or endangering leaves, causing diseased plants Growth is weak and reduces resistance. (2) Wounds caused by mechanical damage, as well as freezing damage, daily burns, etc. (3) Excessive pruning and acidity during the growing season. (4) Poor drainage, inadequate irrigation, and excessive water in the ground area.

2.3 Incidence conditions

Generally, between April and October, during the rainy season, especially after a long period of drought, heavy rain falls, and the gum disease is serious. The age of the peach trees is serious, and the young trees are light. The fruit flow gum is related to the insect pests, and the fruit gum disease is rarely caused by the cockroaches. The clay loam and the fertile soil are easy to occur.

2.4 Prevention methods

(1) Strengthen management and enhance the tree. Add organic fertilizer, pay attention to drainage in low-lying water, acid or alkali soil should be applied with lime or superphosphate, improve soil, salt and alkali should pay attention to salt, reasonable pruning, reduce branch wounds, and avoid continuous cropping. (2) Prevention and control of diseases and insect pests, prevention of pests and diseases, early prevention and control of pests on peach trees such as scale insects, mites, and beetles. The trunks are painted white in winter and spring to prevent freezing damage and daily burns. (3) Before the early spring germination, the diseased tissue of the gelatinous part is scraped off, and the wound is coated with 45% crystal stone sulfur complete agent 30 times liquid or 5° Be stone sulfur mixture, and then coated with white lead oil or coal tar to protect. Chemical control can be used 50% thiophanate-methyl ultra-wet WP 1000 times solution, 50% carbendazim WP 800 times solution, 50% carbendazim WP 1500 times or 50% Pythium WP Powder 2000 times liquid, better control effect. Severely sprayed branches are scraped in autumn and winter. The wounds are disinfected with 5~6°Be stone sulphur mixture or 100 times copper sulphate solution; or with 1:4 alkali water, it also has certain curative effect.

3 peach brown rot

3.1 Symptoms

In the early stage of the young fruit, black spots appeared. Later, the lesions were corked and the surface cracked. When severe, the fruit became brown, rotted, and finally became a stiff fruit. The fruit grows more in the late stage of growth, and it appears brown in the early stage of the disease. It is round and small lesions. Afterwards, the lesions spread rapidly, and the gray powdery balls are exposed. They are shaped like a pile of cells, arranged in concentric circles, with most of the diseased fruit or Completely rotted and landed. The peach blossom infection showed withering and browning, and the diseased flower was dry and attached to the peach branch, and the peach-like tip of the flower rot was dead.

3.2 Causes

The pathogen is a stage of the genus Streptomyces, belonging to the ascomycete sub-gate. The pathogen is suitable for growing in foggy and rainy weather at 25 to 27 °C.

3.3 Prevention methods

(1) Artificial control: In the winter, the diseased branches are cut off, the diseased fruit is removed, and the burnt is collected. Control pests and diseases, pay attention to reduce other fruit surface wounds. (2) Chemical control: Spraying 3~5°Be stone sulphur agent +80% sodium pentachlorophenol 200 times solution in the period of bud expansion, spraying 65% of sensible zinc wettable powder 500 times after flowering for 10 days before harvesting Liquid, or 70% methyl thiophanate 800 times solution or 50% carbendazim 600 ~ 800 times solution or 20% triadazol emulsifiable concentrate 3000 ~ 4000 times solution. Each interval is 10 to 15 days. Various agents are used interchangeably. In the onset period, the diseased plant residues, diseased fruits, diseased leaves, and diseased branches are removed in time. (4) Thoroughly remove sick leaves and debris after pulling. (5) Ventilation and dehumidification of the protected land and the field, and the protection of the ground to reduce or avoid foliar condensation. (6) Applying nitrogen fertilizer, adding phosphorus and potassium fertilizer, and cultivating strong seedlings to improve the disease resistance of the plants themselves. Appropriate amount of water, rainy days or afternoons should not be watered to prevent freezing damage.

4 peach red neck beetle

4.1 Distribution and harm

Distributed throughout the country North and South. It is harmful to peaches, apricots, plums, plums, and cherries. The larvae in the cortex and xylem tunnels cause the trunk to be hollow, the cortex is detached, and the tree is weak, often causing the tree to die.

4.2 Prevention methods

(1) In the middle and late June, the artificial larvae were carried out during the adult emergence period; the larvae damage stage was based on the branches and ground scum and insect feces, and the larvae were assassinated with wire after finding the damaged parts.

(2) Before the adult eggs are laid in early June, the peach branches are painted with white paint to prevent the adults from laying eggs. The white paint formulation is prepared by mixing 10 parts of quicklime, 1 part of sulfur (or stone slag residue), 0.2 part of salt, 0.2 part of animal oil, and 40 parts of water.

(3) In the sunny day of April and May, the swollen leg bee (the natural enemies of the red-necked beetle) was released in the Taoyuan at noon, and the small larvae of the beetle were killed to carry out biological control.

5 Hawthorn Red Spider

5.1 Distribution and hazards

Distributed in East China, North China, Northeast China, South China, Southwest China, Inner Mongolia and other regions. Hawthorn red spiders often cluster on the back of the leaves and the sprouts of the first germination during the big period. After the leaves are damaged, there are chlorotic yellow spots, which gradually expand into reddish-brown plaques. When severe, the whole leaves turn yellow and the coke falls off. When the damage is serious, most of the leaves fall off, affecting the tree potential and flower bud differentiation.

5.2 Prevention methods

(1) Spray 3° Be stone sulphur mixture before germination. (2) The second pass after flowering, avermectin + chlorpyrifos + urea 0.5%, and the treatment of apple leaf curler, green blind mites and so on. The focus of prevention and control is the lower part of the peach tree and the inner mites. (3) In the end of May (before the wheat harvest) spray avermectin + a vitamin salt. (4) Before the end of July, when the number of cockroaches per 100 leaves is 400-500, it is necessary to spray and control the cockroaches. (5) From August to September, the spider mites were used to trap the spider mites. In February of the following year, the worm plate was dissolved and burned.

6 Farmers have the following misunderstandings in the control of peach trees and pests

(1) Blind prevention and treatment: pesticides are applied without clearing the disease. (2) The choice of pesticides is not correct: use insecticides when seeing insects, and use fungicides when seeing spots. (3) The best prevention and treatment period of conventional pests and diseases can not be caught. (4) Improper preparation of pesticides. (5) Spraying pesticides is not correct. (6) Improper time for pesticide application. Due to the above reasons, the period of prevention and control has been delayed, resulting in excessive control costs and poor control effects. In response to the above problems, combined with the actual production of several suggestions for production reference. It is worth noting that the peach peel is thin and is in combination with the flesh. When eating, it is necessary to pay special attention to the application. It is forbidden to use pesticides with high toxicity and long residual effect; pesticides that can be applied according to regulations should not be ripened in fruits. Period of application; should do a good job in the Qingyuan, to minimize the source of the disease, the source of the disease. Agricultural measures are used for prevention and control, and plant pesticides are used. It should be noted that the peach peel is thin and is in combination with the flesh. When eating, it is necessary to pay special attention to the application. It is forbidden to use pesticides with high toxicity and long residual effect; pesticides that can be applied according to regulations should not be ripened in fruits. Period of application; should do a good job in the Qingyuan, to minimize the source of the disease, the source of the disease. Agricultural measures are used for prevention and control, and plant pesticides are used.

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