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Why do pear leaves turn black and how to treat

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Many gardeners and gardeners, planting young pears in their area, do not even suspect that before enjoying the juicy and honey taste of fruits, they may have to face a lot of trouble. For example, the leaves on a pear turn black, because this may be due to a variety of different reasons, each of which requires an individual approach. And if one is easy to cope with, then others can lead to the complete destruction of the affected tree.

Why blacken leaves on pear

In fact, the appearance of black spots and spots on leaves, fruits and even pear bark is a fairly common symptom. And it can be both evidence of an innocent shortage of any nutrient, and a sign of a terrible disease, almost impossible to cure.

Diseases in which leaves and fruits turn black on a pear

Blackening of pear leaves can occur in diseases of both fungal and bacterial origin.

Bacterial burn

If not only the leaves turned black, but the whole top of the pear, and the leaf blades curled along with the color change, then there are all signs of a serious bacterial disease.

Bacterial burn, so called this insidious disease, especially activated in hot weather with high humidity at the same time, when it rains constantly. The very first blackened flower stalks and pear ovaries. At this stage you can try spraying with biological antibiotics: Gamar, Fitolavin.

Attention! Usually, the first symptoms of a bacterial burn on pear leaves appear at the end of June or in July.

The next youngest leaflets are affected, they are covered around the edges with brown-dark spots. Soon, the spots turn black and spread over the entire leaf surface, and the leaves themselves curl up into tubes. Then the tips of the young shoots turn black at the pear. In a relatively short period, all young branches may be overwhelmed by the omnipresent bacteria and look as if they were burned with fire. Therefore, this disease is called a burn.

The most susceptible to insidious disease are young pear trees from 2 to 10 years old. Apparently, this is due to the greater activity of the flow of various physiological processes in young trees against the background of still insufficiently developed immunity. Pears are most often affected by this disease in the southern regions. This may occur either due to the lack of resistance of southern pears to bacteria, or due to the specifics of a hot climate in which the disease spreads too quickly.

Bacteria can be carried by wind, insects and even birds. Infection also often occurs when using a non-sterile instrument when cutting branches.

Scab

Because of this most common fungal disease, not only the leaves turn black, but also the shoots, and flowers, and fruits on the pear and on the apple tree. The disease develops rapidly with the simultaneous development of such factors as increased humidity and heat. If it is not stopped in time, but allowed to progress, all pears and apples in the garden may die over time, especially where they grow with the thickening of the crown.

The first manifestations of the disease can be seen on the leaves of the pear shortly after their blooming. Small patches of a brownish-yellow hue form, over time they grow and darken, then turn black. The leaves of the pear are almost entirely covered with black spots. The causative agent of the disease, the fungus Dothideales, usually hibernates in fallen leaves. Faint dark tubercles appear in them, in which disputes ripen. With the appearance of buds and flowers in pear trees, scab spores are thrown out and actively spread over the leaf surface.

Those pears, which have time to form, are distinguished by hard corky pulp, a large number of dark spots on the peel and low taste qualities. There are varieties of pears that are relatively resistant to this disease. Among them are Gurzufskaya, Dessert, Klapp's Favorite, Strawberry, Victoria, Exhibition, Smuglyanka.

Attention! A variety of Forest Beauty, Marianna, Favorite Yakovlev, Phelps, on the contrary, to a large extent susceptible to scab.

Fruit Rot

The scientific name of this fungal disease is monilioz, and with it, fruits are primarily affected and blackened. The first signs appear in the period of pear fruit pouring and represent small specks of dark brown color. Then they begin to creep away over the fruit, and the pear becomes loose and tasteless. With the intensive development of the disease affects not only the fruits, but also the branches, which begin to shrink gradually.

Black fungus

This fungal disease can strike a pear, either during flowering or during fruit ripening. The following factors contribute to the spread of the disease:

  • lack of light;
  • thickened crown, in which air and light pass badly;
  • planting a tree in a valley with water stagnation;
  • the work of insect pests.

As a result, a dark bloom appears on the leaves and fruits, and the taste qualities of pears are reduced. Interestingly, these black spots are quite easily removed from the affected parts of the sheet. On this basis, the black fungus is easily diagnosed, it is difficult to confuse with some other disease.

Most often, the fungus on pears appears as a result of feeding on sucking insect pests. As a result of their activity, they secrete a sugary liquid, which becomes the basis for the development of soot fungus.

Black pear crab

This disease of fungal origin is sometimes referred to as cytosporosis. As a result of its impact, the bark of pears and branches blacken first of all. True, with a strong defeat, leaves and even fruits begin to suffer, becoming covered with reddish spots. On the trunk, at first, small black specks are formed, which expire with gum. Soon, on the spot of the specks, extensive wounds of a brownish hue appear, and soon the whole trunk on the pear may turn black. It is believed that the disease is not treated, and the badly affected tree must be destroyed. But gardeners have invented many ways, if not guaranteeing a cure, then able to stop the course of the disease.

Pests

Among the main pests of pears, the activity of which leads to the fact that the leaves of the pear turn black, we can name the medyana, aphids and the moth.

Medianitsa is a small winged insect that can jump and fly from tree to tree. Pests suck the juice from the shoots and leaves, resulting in fall flowers and ovaries, the size of the leaves decreases. In the course of its life, the leaves are covered with sticky, sweetish dew, which serves as an excellent breeding ground for soot. As a result, the leaves on pear seedlings turn black and fall off.

Aphids multiplied in large quantities are no less dangerous to the leaves of pear trees. Just as in the case of an attack by a leaflet, the leaves begin to curl, turn black, and gradually fall off.

Improper care

The lack of certain macro- and microelements in the nutrition of the pear tree can also cause blackening of certain leaf areas.

Most often, acidic soils can be deficient in calcium, which results in the appearance of dark yellow areas on the leaves. Over time, they turn black and dry, and the tree looks weakened.

Pear leaves turn black and with a shortage of boron, but in this case they also twist, and the tips of the shoots are deformed and also begin to dry out.

The leaves turn black on the pear and from a lack of humidity in the air when a large amount of dust particles accumulate in it.

What if blackened leaves on a pear

The easiest way to cope with the problem is if black spots on pear leaves appear due to a lack of certain nutrients.

For example, the introduction of calcium nitrate or another complex calcium-containing fertilizer easily saves from a lack of calcium.

Attention! Spraying pear trees with boric acid can help with starvation.

And in order to increase the humidity of the air, it is enough just to regularly spray trees with ordinary water until the problem ceases to be topical.

The most difficult to cope with a bacterial burn. In general, the official effective treatment of a bacterial burn has not yet been invented. But you can try to save the tree with ordinary antibiotics.

First, with the help of a secateur and a container with medical alcohol, each branch on which even the slightest damage is found should be cut off. After each pruning, the secateur must be disinfected in an alcohol solution. All cut pear branches are placed in a metal basin and burned as soon as possible. All sections are also disinfected, wiping them with a rag dipped in alcohol.

Then you need to find one of the following antibiotics:

  • Ofloxacin;
  • Penicillin;
  • Agrimycin;
  • Thiomycin

The drug is diluted in a small amount of boiled water and carefully sprayed each branch and each leaf from all sides. The first treatment is carried out in the phase of budding-the beginning of the flowering of the pear. Then repeat the operation at least three times, every five days.

If the procedures performed do not help, you will have to part with the pear, cutting it to the root. The root must also be burned, and the place where the tree grew should be treated with strong bactericidal preparations.

It is also not easy to cope with a situation when the young pear has a blackened trunk. It is necessary to realize that black cancer is most often the result of frost craps received after the winter, when an infection gets into the weakened wood. But if the disease managed to seize in the initial stage, then you can try to cope with it.

The treatment of black cancer on the pear must begin with careful cutting and even scraping all the affected parts of the wood down to healthy tissue. All wounds must be treated with a solution of copper sulfate and covered with oil paint.

The following components can also be effective for washing the remaining parts of the tree:

  • pharmacy greens;
  • copper preparations;
  • a solution of clay and mullein in equal parts;
  • strong solution of potassium permanganate;
  • saturated salt solution with a few drops of iodine;
  • diluted alcohol or vodka;
  • Vitaros;
  • "Kresoksim-methyl".

Agrotechnical events

In order to cope with many reasons causing the appearance of black leaves on a pear, it is sometimes sufficient to carry out a complex of agronomic and mechanical measures in a timely manner. They include the following actions:

  1. In early spring, immediately after the snow melted, the ground under the pear is cleaned of all plant debris.
  2. Then dig up the soil around the circumference, covering the crown of the tree, at the same time making it organic or mineral fertilizers.
  3. Before blooming, the pear is treated with hot water at + 60 ° C.
  4. In the period of the appearance of buds sprayed with biofungicide "Agat".
  5. After flowering, pear potash phosphate fertilizer.
  6. After 18-20 days, repeat the treatment with biofungicide.
  7. In mid-summer, they feed the pear for the last time, using ash and humus.
  8. In the autumn, in order to prepare for the winter, they do sanitary pruning of a tree; they remove and burn all plant residues.
  9. The kidneys are treated with 5% urea solution. And to disinfect the soil around the tree, use a solution with 7% concentration.
  10. The trunk and main skeletal branches are coated with a solution of lime with the addition of copper sulfate.

Biological agents

Recently, quite effective biological agents have appeared, consisting of beneficial bacteria, which can quite successfully fight against certain diseases. Even with a bacterial burn on pears in the early stages of the development of the disease, you can try to cope with biopreparations.

For this you can use Fitolavin and Gamar. The first drug has a really strong effect and can be used at the beginning of the growing season, before the fruit ripens. 20 ml Fitolavin diluted in 10 liters of water and the resulting solution is watered and sprayed with wood.

It is advisable to use gamair during fruit ripening, as it is completely safe for human health. 2 tablets Gamair diluted in 1 liter of water and sprayed with pear branches.

Also, biological products will be effective against soot fungus. After all, the microorganisms used in them, eat sugar from insect secretions, thereby leaving the fungus without sustenance. You can use Shining, VostokEM1 and Baikal.

Chemicals

All fungal diseases, as a result of which blackened leaves and branches on a pear, should be treated at the first detected signs with copper-containing preparations: Bordeaux liquid, copper sulfate and others. Especially effective spraying these funds in the spring and autumn periods. After blooming of kidneys it is better to use fungicides - Fitosporin, Folikur, Topsin.

You can also use solutions prepared according to the following recipes:

  • 300 g of copper sulphate + 350 g of lime + 10 l of water (before bud break);
  • 100 g of copper sulphate + 100 g of lime + 10 l of water (after bud break);
  • 30 g of Azofos + 2 ml of SCOR (fungicide) + 6 g of biletone + 40 g of chlorine oxide of copper + 10 l of water.

And against insect pests, it is necessary to use insecticides such as Fitoverm, Alatar, Biotlin and Fufanon. All damaged leaves and fruits are necessarily removed from the pear and burned.

Attention! And if the moment was missed, and the number of insects exceeded all possible limits, then it is worth using a solution of trichloromephos for processing.

Folk methods

As for insect pests, the easiest way to get rid of them is to wash them off the trees with good water pressure.

For spraying, you can also use a solution of conventional dishwashing detergent in water. The procedure is repeated every other day for two weeks.

You can also dilute 400 ml of 70% alcohol and 1 tbsp in 1 liter of water. l liquid soap and spray trees in the morning, until the sun rose.

Are good against insects and infusions of all kinds of herbs: garlic, tansy, onion peel, yarrow and tobacco. For this 400 g of any herb pour 3 liters of water and insist about 3-4 days. Add a handful of wood ash. Filter, bring to a volume of 10 liters and sprayed the trees.

Preventive measures

The timely implementation of all agrotechnical measures will already serve as an excellent prevention of many diseases of the pear and will help prevent the blackening of the leaves.

Therefore, in addition to the above measures, one should not forget:

  • regularly carry out pruning of trees, especially sanitary;
  • do not forget to disinfect instruments after pruning;
  • ensure proper watering;
  • make all the necessary nutrients;
  • not to allow overmoistening of the root neck of the tree;
  • provide reliable protection from frost in the winter.

In addition, it is important to choose a healthy and high-quality material for planting.

Conclusion

If the leaves on the pear turn black, this can be a sign of both the most dangerous and quite harmless diseases. But in fact, and in another case, it is necessary, first of all, to make a correct diagnosis. After all, the success of the solution of the problem will depend on this. And the abundance of modern agricultural methods, as well as chemical and biological remedies will help to cope with any problem.

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