What are the causes of anthracnose in peach trees? How can I protect myself?

The young fruit quickly dries out after being infected, turning into a stiff fruit that hangs on the branches. When the disease occurs, the larger fruit sinks and turns brown, and when wet, it produces pink mucus, and the diseased fruit falls off quickly, or the whole fruit rots and loses its moisture, turning into a hard fruit that hangs on the branches. The onset of branching occurs mainly on fruit branches in early spring.

The diseased spot is brown rectangular, slightly depressed, and has a running glue. When the weather is wet, the diseased spots are also densely covered with pink spores. When the diseased point surrounds the branch for 1 week, the upper part of the branch, i.e., the wilted, diseased branch and the dead part, the leaves shrink and droop and roll forward into a tube.

Pathogenesis: fungal disease. Mycelium overwinters on diseased dead branches and diseased fruits, and in the early spring of the following year, they produce spores, infect the spores, and then spread to flowers and fruits, exacerbating the damage.

Continuous rainfall, hot and humid weather, easy to get sick when it is hot, and usually erupts after continuous rain or heavy rain. It is easy to get sick when the garden temperature is low, the drainage is poor, the pruning is rough, the branches are dense, the tree vitality is weak, and the nitrogen fertilizer is partially applied. The disease occurs three times a year in Shanghai, and is found on fruit branches from mid-March to early April.

It occurs on young fruits in early and mid-May, as well as ripening in June and July. Of the year, the damage is greatest during the young fruiting period. The incidence of the disease varies greatly between breeds.

In general, early-maturing varieties are the most affected, followed by medium-maturing varieties, while late-maturing varieties are more resistant to disease.

3. Prevention and control methods:

During winter pruning, dead branches, stiff fruits, and stumps should be carefully removed from the tree to eliminate the root cause of overwintering diseases. Perennial senescent and weak branches, which are prone to accumulation and latent pathogens, should also be cut off. At the same time, the main side branches that are too tall and too large should be retracted to facilitate the renewal and revival of the crown and branch groups, as well as the cleaning and spraying of the garden.

Cut off diseased branches before and after budding to prevent reinfection; Fruit branches with symptoms of leaf curling should also be cut off and buried deeply.

Choose disease-resistant varieties.

Strengthen drainage, increase the amount of phosphorus and potassium fertilizers, enhance tree vitality, and avoid excessive dense and long branches.

Spray 1-2 times 1:1:100 Bordeaux mixture at the budding stage (disabled after leaf development).

The young fruiting stage begins after flowering, with a zinc-copper-lime solution (350 g of zinc sulfate, 150 g of copper sulfate, 1 kg of quicklime, 100 kg of water), once every 7-10 days, and controlled 3-4 times in a row. These are the harmful symptoms and prevention methods of peach anthracnose that have been written.

The cause of anthracnose in peach trees is due to the accelerated epidemic of Longospora discs under the condition of continuous rainfall during the period. Strengthen cultivation management, reasonable fertilization, timely removal of water accumulation in orchards, timely removal of erect long branches in summer, improve ventilation and light transmission conditions, and remove pathogens.

The low temperature and rainfall of peach trees in the flowering and young fruit stages are high, and the incidence is high. During the fruit-ripening period, the disease is severe in a warm, cloudy, foggy and humid environment. Remove dead branches, dead fruits and fallen branches and leaves on the ground from the tree in a timely manner, and deal with them in a centralized manner.

Prevent water accumulation after rain to reduce humidity in the park. Appropriate application of phosphorus and potassium fertilizers can promote the growth of peach trees and improve disease resistance.

The causative agent that causes peach anthracnose is Longospora disc. When the average temperature reaches 10 12 and the relative humidity of the air reaches more than 80 in the early spring of the following year, the disease spots begin to produce conidia, and the spores spread by wind and rain and fall to the young fruits, new shoots and leaves, forming a primary infection. The peak period of onset is from mid-May to mid-June.

The occurrence of anthracnose in peach trees is also closely related to rainfall, and the continuous rainfall during the onset period makes the disease aggravated by the repeated infection of the pathogen. Canopy closure and partial application of nitrogen fertilizer are conducive to the disease.

Pesticide control, in the flower bud expansion stage, spray 1:1:160 Bordeaux liquid, or 5 Baumé stone sulfur mixture, after leaf development can not use Bordeaux liquid.

After flowering, spray fungicide in time, you can use 70 methyl tobuzin wettable powder 1 000 times, or 50 carbendazim wettable powder 800 times, or 40 carbon trane wettable powder 600 times, or 75 chlorothalonil wettable powder 1 000 times.

At the beginning of the disease, light brown lesions appear on the leaves, and after expansion, they appear nearly round, irregularly shaped, yellow-brown; There are small black-brown dots on it, and ochre-red muxspores overflow under high humidity, so what are the prevention and control methods of anthrax? In the early stage of the disease, cut off the diseased leaves, and burn the dead branches and leaves in the green space in time to prevent the expansion; Do not plant too dense or place indoor flowers too densely, do not pour indoor flowers from the top of the plant, and always keep ventilation and brightness. Clean the countryside in winter, and burn the sick and remnants in time; During the onset of the disease, spray 1000 times of 75 methyl tobuzine wettable powder, 600 times of 75 chlorothalonil wettable powder, or 500 times of 25 carbon trane wettable powder, 900 times of 25 diphantyl emulsifiable concentrate, or 50 antibacterium 800 to 1000 times of grinding, or 50 times of 500 times of carbon Fumei wettable powder.

Once every 7 to 10 days, 3 to 4 times in a row, the prevention and control effect is better.

In terms of early prevention and management, 3-4 Baumé stone sulfur mixture, 1000 times 12 alconazole, 250 times 80 sodium pentachlorophenol, 10 heavy diesel emulsion and other drugs can be used before the germination of fruit trees. At 10-15 days after flowering, use 200 times high lipid film emulsion, 1000 times 70 thiophanate-methyl, 1000 times 72 fu? Zinc and other drugs are sprayed for prevention.

Prevention and control methods of peach tree anthracnose 1, pruning and disinfection.

After the tree leaves fall in autumn to early spring, combined with fruit tree pruning, all the diseased branches, leaves, fruits, residual branches and fallen leaves and weeds in the garden are cleared out of the garden, and they are buried or burned in a concentrated manner, and sprayed for disinfection and sterilization of the whole garden.

2. Fertilization and disinfection

When fertilizing, try to increase the application of rotting organic fertilizer, farmhouse manure fertilizer, biological fertilizer, scientific proportion of nitrogen, phosphorus and potassium fertilizer, and do not overapply nitrogen fertilizer.

When applying basal fertilizer in autumn, quicklime can be sprinkled with quicklime throughout the garden for soil disinfection according to the dosage of 60-80 kg per mu.

3. Watering prevention

According to the demand for water during the growth period of peach trees, reasonable watering should be carried out in different growth periods, and flood irrigation should not be carried out in large quantities, and drainage should be carried out in time after rain to prevent excessive humidity in the field from inducing diseases.

4. Thinning flowers and fruits

According to the soil moisture, tree potential, tree age, planting varieties and large loads, do a good job of pruning fruit trees in each season, and reasonably thin flowers and fruits during the flowering and fruit period.

Maintain the uniform distribution of fruit branches, the moderate amount of flowering and fruit set, the excellent wind and light environment of the tree body, and the balance of vegetative growth and reproductive growth.

5. Prevention and treatment drugs

In terms of early prevention and management, 3-4 Baumé stone sulfur mixture, 1000 times 12 alconazole, 250 times 80 sodium pentachlorophenol, 10 heavy diesel emulsion and other drugs can be used before the germination of fruit trees.

At 10-15 days after flowering, use 200 times high lipid film emulsion, 1000 times 70 thiophanate-methyl, 1000 times 72 fu? Zinc and other drugs are sprayed for prevention.

In the new slightly extracted repentance period, young fruit stage, and fruit expansion stage, 800 times 75 carbendazin, 600 times 50 antibacterium, 1000 times 70 methyl tobuzin or Bordeaux liquid and other drugs were sprayed to protect the fruit.

6. Spraying control

In the early stage of the disease, 700 times 70 mancozeb + 900 times 70 thiophanate-methyl, 700 times 70 mancozeb + 800 times 50 carbendazim, 700 times 70 mancozeb + 800 times 10 difenoconazole and other drugs were used for compound spraying and control.

7. Serious treatment of diseases

When the disease is severe, can you use 600 times 70 thiophanate, 500 times 50 iprodione, 2500 times mycloconazole, 2000-2500 times 10 difenoconazole, 1000-1500 times carbendazim? Ethyltrimencarb and other drugs are sprayed for prevention and control.

Fruit tree rot, also known as branch blight, mostly occurs on main stems and long branches. The questioner directly asked what kind of medicine can be used**, in fact, this disease is more important to prevent. Rot disease is more common in the main and long branches, and can also cause root rot in the early stages, and often cause the long branches or even the whole fruit tree to die in the middle and late stages.

In the early stages of the disease, we are generally negligent and careless because it is not too obvious. The roots of the diseased tree will initially turn light brown with a slight downward dentation, and there will be pale yellow sap discharge, and eventually it will turn purple-brown and wither.

If we look at it, we will see that the lesions are tan and smell of sake lees. Fruit tree rot disease is also called blight, the pathogenic bacteria generally spend the winter in the branch disease tissue, and the spring arrives according to the precipitation and insect dispersal, mainly from the wound invasion injury, easy to make the roots of the tree oily, the root mechanism rots, a little bit of pathogenic bacteria in the room, serious time the tree withered. In the early stage of the rot disease, there are many light brown water traces on the branches, and you can feel a clear surge feeling, and when you light it with your hands, there will be dents, and the rot disease of fruit trees is very serious, and there will be brown sap overflow.

Fruit tree rot disease, the diseased area can be easily peeled off, after peeling off the roots, you can see the rot of the phloem of the fruit tree, often see light brown color, and there will be the smell of wine troughs. In the middle and late stages of the disease, there will be collapse after drying up due to lack of water at the disease location, and gaps will occur at the junction with the outer skin of healthy branches. The pH of the soil layer is generally suitable for the growth and development of fruit trees, and if the pH is exceeded, it is easy to cause the leaves of fruit trees to wither and yellow.

The effective ratio of N, P and K required for the growth process of fruit trees in the whole year is 1, and too much phosphorus or special phosphorus fertilizer is easy to harm the absorption and application of iron, magnesium, zinc and other elements.

Too high alkali and excessive phosphorus will inhibit the absorption and use of trace elements, and fruit trees will be prone to physiological diseases such as yellowing and twigs. Yellowing and twigs have no photosynthetic effect, which can further make the root growth and development of fruit trees poor, cut the soil layer, and susceptible to unhealthy growth and development of rhizomes. Gently pull the stem with your hand, the roots are very easy to shake, the capillary roots are very few, and some of the roots of the teeth are atrophied.

Peach brown rot damage to the fruit, from veraison to ripening can be harmful, the fruit in the early stage of the infection of the disease is dark brown annular lesions since then and gradually spread to the surface of all fruits, until the fruit rots, the lesions damage the fruit has obvious characteristics: black-brown velvety mold bushes, the figure produces a circular ring pattern, the fruit of the disease generally falls down, stiff fruit.

Peach root rot can be said to be a more serious disease, and it is still very common, and this disease will seriously affect the yield of peach trees. Peach root rot generally occurs in late April to the month of April, when the leaves of peach trees suddenly wilt and fall off. Because the peach tree is a small tree, its root system is relatively shallow, so when planting the tree, it is appropriate to plant a little shallower, and you can also apply a little more organic fertilizer.

Symptoms of peach tree rot disease mainly damage the trunk and main branches. The disease of the tree can occur from early spring to late autumn, and the disease occurs quickly in early spring. After the branch is damaged, the lesion is slightly sunken, and the surface has a flow of gum the size of a grain of rice.

Later, with the increase of the flow glue point and the increase of the amount of flow gum, the tissue at the flow gum decay, slightly soft, reddish-brown, and smelled of sake lees. In the later stage, the lesion loses water and shrinks into depressions, and there are many gray-white dots on it, which is the subseat of the pathogenic seedling. When the weather is wet, reddish-brown filamentous spore piles can be expelled from the subbase.

Twig injuries often show sunken ulcer spots, and in severe cases, the branches die.

Peach rot disease can occur from early spring to late autumn, and April to June is the peak period of the disease, and the damage to peach trees is also the greatest. The prevention and control of peach tree rot disease should pay attention to the following aspects, the first is to adopt the high ridge cultivation mode, should insist on digging deep pits, increasing organic fertilizer, nitrogen, phosphorus and potassium combination, to create good conditions for the growth of seedling roots, reduce the causes of disease. The second is to select high-quality disease-free strong seedlings, seedlings planted with 50% carbendazim wettable powder 500-600 times liquid, soaked seedlings for 20 minutes, and then rinsed with water to disinfect seedlings and prevent root rot.

The third is to strengthen the management of fertilizer and water, small trees should promote the roots and seedlings, and large trees should be reasonably loaded to prevent the tree from weakening. Increase the proportion of microbial fertilizer in fertilization, improve the soil properties and structure through microbial flora, and restore the ability of soil to store water and fertilizer.

Peach Tree Major Pest and Disease Prevention Techniques:

1. Peach bacterial perforation disease. It mainly damages leaves and fruits, causing leaf perforation and peeling and fruit cracking. The lesions on the leaves are nearly rounded, about 2 5 mm in diameter, reddish-brown, or several lesions are connected to form large lesions, and there are yellow-green halos on the edges of the lesions; The fruit is damaged, initially a light brown water-stained small round spot, then expands to brown and slightly concave.

Prevention and control methods: pay attention to remove diseased and dead branches and eliminate pathogens during winter pruning.

In early spring, spray Bordeaux liquid during the germination period of peach buds, or spray Baume 5 degrees stone sulfur mixture to kill overwintering bacteria; In the early stage of the disease, 72 streptomycin sulfate wettable powder, quinoline copper suspension and other agents can be sprayed.

2. Peach gum disease. Glue flow can occur on branches, new shoots, leaves, and fruits, with branches being the most serious. The bark of the diseased branches is rough, cracked, and not easy to heal, and a yellow-brown transparent gel is discharged.

There are many reasons for peach tree gum flow, one is physiological reasons, such as suffering from pests and diseases, improper fertilization (lack of fertilizer or partial nitrogen fertilizer), soil clay and heavy drainage, excessive pruning in summer, too deep planting, and one is caused by fungal infection.

Control methods: Strengthen comprehensive management, promote the normal growth and development of the tree, and enhance the tree potential.

The branches with serious flow gum should be scraped in autumn and winter, and the wound should be disinfected with Baume 5-6 degree stone sulfur mixture or copper sulfate solution.

The main stem is whitewashed, and the main stem is whitened twice in winter and summer to prevent the occurrence of gum disease.

3. Peach borer. It is an important fruit boring pest, after hatching, the larvae are bored from the fruit pedicle or the junction between the fruit and the leaf and the fruit and the fruit, and reach the heart of the fruit, and there are a large number of insect feces and yellow-brown glue in the damaged fruit and outside the fruit.

Prevention and control methods: scrape off the old warped bark of peach trees in winter or early spring to eliminate overwintering cocoons; In the growing season, the damaged fruit is removed in time, and the overwintering larvae are collected and killed in a concentrated manner before the fruit is picked in autumn. At the egg stage and larval hatching stage, 25 larvalurin suspension agent, 20 fenvalerate EC and 5 cypermethrin EC can be sprayed for control.

4. Peach heartworm. In recent years, the harm of peach heartworm has become more and more serious, which has a great impact on the quality of fruits.

Control method: Before the overwintering larvae are unearthed, cover the ground of the tree plate with a wide plastic film to prevent the overwintering adults from flying out and laying eggs, and combine it with ground pesticide control, the effect is better.

In the initial incubation period of larvae, 10 cypermethrin EC, or deltamethrin EC, or avermectin EC, and 25 chlorpyramide suspension were used to spray evenly. The focus of the spraying is on the fruit, spraying 2 times per generation, with an interval of 10-15 days.