It is important to establish the cause

it is important to establish the cause Blog

Amateur gardeners and vegetable growers usually associate damage to plants with infection and, as a rule, chemical treatment is chosen as a control measure. But this does not always help, since the cause of the disease is often a non-infectious process caused by excessively high or, conversely, excessively low temperatures and humidity, impaired mineral nutrition, and adverse human impact. Treatment of plants with pesticides in this case leads to their even greater weakening.

What could be the causes of tree damage?

In summer, due to overheating of the bark during the daytime, more often from the southeast side, sunburns of the bark of fruit trees can be observed. Reddish, initially vesicular, then depressed spots appear on it.

In autumn, winter, early spring, due to sharp fluctuations in temperature, sun-frost burns often occur. On burnt trees, frost cracks and cracks appear, which, with especially sharp temperature fluctuations, capture not only the bark, but also the surface layers of the wood, as a result, the bark exfoliates.

During cold snaps, even without frost, when the temperature drops below the minimum for normal plant development, whitishness, yellowing of leaves and oppression of heat-loving plants are observed.

The alternation of frosts and warming in winter leads to the formation of frost holes and peels on tree trunks as a result of uneven compression and expansion of the inner and outer parts of the trunks.

To protect the boles and skeletal branches of trees, it is necessary to whitewash them at least twice: in autumn (in November) and in spring with lime milk. For better adhesion, heated wood glue (about 0.5%) is added to it. If, nevertheless, wounds appear, they should be cleaned, disinfected with 1% copper sulfate and covered with garden putty.

Young trees can be protected by tightly closing the trunks in the fall, when stable frosts set in (tying at an earlier date worsens the winter hardiness of plants), spruce branches – spruce branches. Put them with the needles down.

Violation of moisture supply also leads to various deformities. An increase in soil moisture following a relatively dry period often leads to cracking of fruits and vegetables.

High soil moisture, strong lighting in greenhouses are common causes of non-infectious tomato leaf curl. With the deterioration of transpiration associated with the onset of dry hot weather after rain, plants quickly lose turgor, wither and then die. In this case, it is possible to prevent or slow down the death of leaves by loosening the soil in a timely manner and applying mineral fertilizers, especially chlorine-containing ones.

Plants can grow and develop normally, give high yields only if all the necessary nutrients are present in the soil, moreover, in a certain ratio that changes in different phases of the annual cycle.

The cause of damage is a lack of trace elements

Each element has its own specific meaning. Nitrogen plays an important role in growth processes. With its deficiency, plant growth is delayed, the leaves on them form small, pale green. An apple tree, for example, needs a lot of nitrogen in spring and early summer during a period of increased growth. Therefore, early spring fertilization of trees with nitrogen gives good results.

The importance of phosphorus in plant life is great and varied: it accelerates the onset of fruiting and increases the sugar content of fruits, enhances winter hardiness and drought resistance, and promotes the absorption of nitrogen fertilizers. With phosphorus starvation, brown spots form on the leaves of many plants. This disease is especially characteristic on potatoes: rusty spots are visible on the cut of the tuber, hence it got its name – glandular spotting.

Potassium helps to increase the resistance of trees to frost and drought, increases the resistance of plants to fungal diseases, and improves the keeping quality of the crop. Usually clay soils contain enough potassium, and sandy soils are poor in it. As a rule, potassium deficiency is accompanied by mild leaf chlorosis between the veins. Acute potassium starvation of fruits can easily be seen by burning the edges of the leaves. It is brown in apple and black in pear. On diseased potato plants, the leaves wrinkle, later the old plates turn slightly yellow. First, the top and edges of the leaves, and then the whole plant acquires a bronze color.

Iron is usually found in the soil in sufficient quantities, but in alkaline, in particular carbonate, soils it becomes indigestible. Iron deficiency poses a threat to plant life. Tops of shoots, young leaves become pale yellow, green color is preserved only along the veins. Trees weaken, lag behind in growth, their top often dries out, and they die. This phenomenon is called glandular chlorosis. Chlorotic trees before and after the growing season are recommended to be sprinkled with a solution of iron sulfate, to make, under them, full mineral and organic fertilizer. A good effect is obtained by sowing alfalfa, clover, sweet clover in the aisles of the garden (but we must not forget to water the trees).

Of the trace elements, most often plants lack boron, zinc, copper, manganese, less often – molybdenum, cobalt.

With a lack of boron, which is often observed on light sandy, podzolic and carbonate soils, the apple trees are less likely to set fruits, they crumble more strongly, external and internal corking appears, accompanied by the formation of depressions, cracks and fruit deformation. With a strong boron starvation, the fruits completely lose their presentation.

The lack of boron in beets is manifested in the death of the growing point and young parts of plants, the young inner leaves of the rosette turn black and dry. This disease is called heart rot. Boron deficiency can be eliminated by spraying the plants with a solution of boric acid (5 g per 10 liters of water).

The lack of zinc in the apple tree causes rosette: bare shoots bear a rosette of small narrow leaves only at the tops. Often, rosette is accompanied by chlorosis and leads to the death of shoots and entire branches, the cessation of flowering, fruiting and death of the tree. Rosette is usually cured by spraying the plants in the spring, before the buds swell, with a solution of zinc sulfate (500 g per 10 liters of water).

The most characteristic sign of copper deficiency is the formation of brown spots on the leaves. In hot weather, the signs of copper starvation increase. First, the upper leaves become stained, then they become deformed, turn brown and fall off.

With many years of suffering from copper starvation, the tree takes on a bushy appearance. It can be treated by adding finely ground copper sulphate to the soil or spraying the trees with a Bordeaux mixture.

Signs of magnesium starvation in fruit appear differently depending on the variety. In many varieties, yellowing is observed between the veins of the leaf, and the veins themselves retain a dark green color. The yellowed areas subsequently die off. Diseased leaves fall off prematurely, the fruits are formed small, slightly colored, with low taste. In cherries, yellowing of the leaves occurs in the middle of the leaf blade. In raspberries, the color of the tissues between the veins of the leaf is yellowish with a red tint, in blackcurrant it is purple-red. Due to the shedding of diseased leaves in acute magnesium deficiency, trees can be completely bare already in August.

The lack of calcium primarily affects the root system, slows down its growth. Plants are especially sensitive to a lack of calcium on podzolic soils, so they need to be limed.

Do not treat plants without establishing the cause of the disease

Severe damage to plants can also develop with the directed use of pesticides, when the regulations for use are not observed. Exceeding the concentration of drugs, violating the timing of treatments (for example, iron or copper sulfate, 3% Bordeaux liquid at a later period than allowed) can lead to burns and leaf fall.

Non-communicable diseases pose a threat to the life of plants, in addition, weakening them, contribute to the defeat of various harmful organisms. So, trees with frost holes, burns become a victim of stem pests, bole diseases, which can quickly lead to their death.

This is by no means a complete list of examples showing how severe plant damage can be caused by non-communicable diseases, the causes of which are a variety of factors. But even these examples clearly show how important it is to correctly establish the cause of the disease in order to select the necessary control measures in each specific case.

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