Pests and diseases of courgettes

Even the most unpretentious crops require care, and gardeners and gardeners have to make a lot of efforts to grow a good harvest. A lot of trouble to the cottagers is caused by zucchini diseases, and pests are also pestering insects. To deal with them, the enemy must be known in person, ie, it is necessary to study in detail what can threaten plants and how to deal with it.

Causes of Disease Development

The source of infection are, as a rule, fungi and viruses. While they are in the soil, the harvest will suffer from year to year. Infections are affected by all the pumpkin crops, and the most painful among them are zucchini. Diseases of leaves, fruits and other parts of these plants are observed, as a rule, in cold and wet weather.

It contributes to the development of diseases for a number of reasons: sudden changes in night and day temperatures, lack of trace elements, excessive or, conversely, insufficient moistening of the soil, watering with too cold water, etc. A good preventive measure is the timely application of fertilizers with the observance of dosages, maintaining the necessary humidity, Control of weeds. In closed greenhouses for the purpose of prevention, it is recommended to disinfect with a solution of bleach. It is necessary to immediately react to the emerging signs of any disease of courgettes and their treatment to begin without delay.

Anthracnose

All ground parts of the plant suffer from it. This disease usually begins with the formation on the leaves of rounded yellow-brown spots, which gradually transform into stems and fruits, where they acquire an oblong form. Over time, the area of affected areas increases, they appear mucous plaque. Leaves as a result wither, and the fruits wrinkle, acquire a bitter taste and rot. The appearance of signs of anthracnose on the root part of the plant is a clear signal that the plant is dying. It contributes to the development of the disease excessive humidity, as well as watering in the hot time of the day.

More often anthracosis affects crops grown in greenhouses and greenhouses, although the causative agents of almost any zucchini disease in the open ground (with photos of plants affected by this disease, can be found below) feel good too. Infection occurs throughout the growing season.

Pathogenic microorganisms can persist on the diseased plant for a long time, hibernating on its remains. The fight against infection is reduced to careful selection of seedlings and seed dressing. In addition, immediately remove all affected plants and then disinfect the greenhouse. It helps to cope with the disease Bordeaux fluid or sulfur colloid.

White rot

It covers the stems, leaves of the plant with a dense coating of white color. This is the fruiting body of the sclerotia fungus, which is the causative agent of this zucchini disease (in the open and closed ground the fungus feels equally well). The damaged tissues of the plant soften, the leaves dry up, and the fruits turn into a gruel-like mass. The disease spreads in cold and wet weather, especially if the plantings are heavily thickened. More zucchini are more susceptible to it during fruiting. The infection is perfectly preserved in the soil and on the remains of damaged plants. Infection can occur in a variety of ways - through air currents, mechanical damage, during care.

To get rid of white rot, you can only completely destroy the affected parts of the plant, sprinkling the cut with charcoal or rubbing with a half-percentage solution of copper sulfate. To prevent the disease, timely harvesting of weeds, use of warm water for irrigation, non-root dressings, including copper sulfate, zinc sulphate and urea at the rate of 2 g, 1 g and 10 g, respectively, for every 10 liters of water. Sections of the stem, where only the signs of the appearance of white rot are seen, can be wiped with a piece of cotton wool and sprinkled with crushed chalk or charcoal.

Gray rot

Usually occurs on young ovaries, then turning to leaves. The affected parts of the plant become watery, softened and covered with a touch of gray. Under the film, the zucchini rot is much more likely to suffer from this. Diseases in the open ground rage, as a rule, only during prolonged rains or in cold weather.

The causative agent of gray rot is the main source of infection. It can remain in the soil for up to two years. The spread of the disease is also facilitated by insects that carry fungal spores from one plant to another.

To prevent gray rot, like all zucchini diseases, it is possible only by observing the rules of crop rotation, destroying the weeds in time and making the necessary fertilizing. Discovered on the plant affected ovaries and fading leaves should be immediately removed.

Root rot

Most often, this disease occurs in a sheltered soil. It appears that the roots begin to darken, become soaked, and the stalk gradually grows brown. The lower leaves turn yellow and fade. Root rot is most susceptible to weakened plants. Under adverse conditions, they are more likely to be affected by a parasitic fungus. Contribute to the disease is too early planting, sudden temperature changes, the use of cold water for irrigation, excess moisture in the soil. This and other types of rot - quite often infectious zucchini disease. The struggle against them is carried out approximately equally and consists in observance of the agrotechnics, conducting disinfection of the soil, maintaining a certain soil moisture.

Powdery mildew

This disease first affects the leaves of the plant. They form spots of loose grayish plaque, which after a while merge, covering and stems. This is the sporification of the fungus, which is the causative agent of the disease. It disrupts the process of photosynthesis, absorbs nutrients, which leads to a decrease in yield. The resulting cleistocarpas can infect plants in the next season. The fungus is completely preserved during the winter, spending it on the remains of weeds. From the moment of infection and before the first signs of the disease appear, it takes about 3-4 days.

Most suffer zucchini from powdery mildew, when there are sharp fluctuations in air humidity, with an excess of nitrogen fertilizers, insufficient irrigation.

Avoid this disease can, if the weeds are weeded in time, after harvesting, remove all plant remains and dig deep the soil. At the first signs of fungal infection, the plant should be treated with any of the following preparations:

• Gray colloidal - from 40 to 100 grams of sulfide per 10 liters of water for treatment in sheltered soil.
• Gray ground.
• "Isophene" (for greenhouses - 60 grams per 10 liters of water).
• Inflorescence mullein. It is prepared in the following way: 1 kg of manure should be poured in water (3 liters) and leave for 3 days to infuse. After that, the solution is filtered and before the treatment is diluted with water (1: 3).
• Ogorodniki often use for spraying the usual potassium permanganate - 1.5 g potassium permanganate per 10 liters of water.

Peronosporoz

This disease zucchini susceptible at any age. At first, on the leaves appear rounded spots of yellow-green color, which gradually become brown. Soon they begin to wither and crumble. The areas of sporulation are located on the underside of the leaf and are a violet plaque. The disease develops during a period of heavy dew, fog, when the humidity is particularly high. Its causative agent may persist in the soil for several years.

Cope with the disease is possible only by disinfecting or completely replacing the soil. One of the preventive measures is the frequent airing of the greenhouse or greenhouse.

Ascochitis

The causative agent affects the leaves and stems of the plant. First, they form gray spots, which are soon covered with black dots. The infection begins, as a rule, with the lower leaves, which receive the least amount of light, and gradually moves to the upper ones. The harvest from this disease-damaging crop is severely affected. Fruits at the end of the season is saved a little - infected with a fungus, they quickly dry up and turn black. The causes of infection are usually sharp temperature changes, high humidity and excessive thickening of plantings.

It is possible to get rid of a fungal infection by eliminating the excessive watering, it is equally important to get rid of the affected plants in a timely manner. Small pockets of the disease can be powdered with chalk powder mixed with sulfuric copper in a ratio of 1: 1. This measure will avoid the spread of infection.

Black mold

On the leaves, you can first see small rusty spots, which eventually become dark plaque. This is the spore of the fungus. Gradually, the leaf blade under the stain dries up and crumbles, causing holes to appear on it. The development of fruits stops. It is possible to get rid of this zucchini disease by completely burning the affected plants.

Fusarium wilt

The soil fungus, which is the causative agent of the disease, penetrates into the root system, growing in the vessels of the plant. As a result, the stem rotates at the base itself. The leaves are covered with spots, the plant fades, breaks and dies. Cope with the problem will help only complete replacement of the soil. For the purpose of prevention, strict adherence to the rules of agricultural technology and the timely destruction of weeds on the site.

Bacteriosis

The onset of the disease is characterized by the appearance on the cotyledons and on the real leaves of ulcers of brown color. On fruits, they also occur (only a small size and brown color), leading to their distortion. Bacteriosis can persist for a long time on plant remains and seeds. Progression begins with sudden changes in temperature and excessive humidity. The spread of the disease is facilitated by insects, droplets of water and particles of infected plants. Very severely affected by the crop from this zucchini disease. Measures to combat it necessarily include seed treatment with zinc sulphate. They are placed in a 0.02% solution per day, then slightly dried. Plants with the first signs of bacteriosis are treated with Bordeaux fluid (10 g of lime and copper sulfate), and with a preventive purpose - copper chloride.

Viral diseases

Most zucchini suffer from cucumber and pumpkin mosaic. In this case, the leaves are mostly affected.

Cucumber mosaic is manifested in the form of small yellow-green spots. After a while, the leaves twist, and between the veins are formed tubercles. The growth of plants slows down, and they practically do not yield a crop. The reservoirs of infection are perennial weeds - in their roots the virus tolerates winter very well. With seeds it is not transmitted. For this reason, the whole struggle is reduced to the destruction of weeds.

With pumpkin mosaic, the leaves are also covered with light green spots. But then the ends of the veins begin to stand out at the edges, since the growth of the leaf blade slows down sharply. The flesh completely drops out in places. The virus that causes this disease is transmitted through the seeds. It can persist for many years. Before planting, it is recommended that the seeds be heated at a temperature of 50-60 ° C for three days.

Insect pests

Not only the diseases of zucchini (in the open ground), the struggle with which requires considerable effort, bring a lot of trouble gardeners. Rodents often eat seeds, seedlings suffer from a wireworm and a bear. However, most harm is caused by insects.

Smoothing aphid

Its larvae spend the winter on the remains of plants and with the onset of spring form whole colonies. Reproduces very quickly, giving offspring up to 20 times per season. By the summer, aphids have wings, and, being able to move even faster, sucks out the zucchini from the zucchini, damaging the leaves and stems. Affected parts of the plant gradually dry out and deform. If we take into account also what kind of disease zucchini tolerates aphids, then once it becomes clear that it must be seriously combated. To prevent the invasion of this insect helps to destroy all plant residues after harvesting and thorough digging of the soil. If the aphids are found to get rid of it, help infusion of pomegranate pepper. It is prepared as follows: mix pepper, powdered (30 g), liquid soap (1 tbsp.) And wood ash (3 tbsp.). The resulting mixture is diluted in 10 liters of water, insisted for 24 hours, then after filtering, they start spraying the affected plants. The broths and infusions from potato leaves, onion husks, and tobacco are also good.

Spider mite

These rather small insects (no more than 0.4 mm in size) are capable of causing irreparable damage to the crop. They colonize plants as soon as warm days occur, placing themselves on the underside of young leaves and feeding on cell sap. It also lays eggs, of which larvae appear in a week. The damaged leaf is covered with light dots, then acquires a marbled spot and withers.

The fight against this pest is the burning of all the remains of vegetation after harvesting and deep digging of the soil. When a mite is found on zucchini, it is possible to practice spraying with various means. Especially effective infusion of onion husk. Half filled with a bucket is poured over with boiling water and insisted 24 hours. Then filter and dilute with water in a ratio of 1: 2. Used for spraying and infusions of potato leaves, datura ordinary. To allow the solution to adhere to the surface of the leaf, it is recommended to add a little laundry soap to it.

Whitefly

It appears in large numbers towards the end of summer, settling on the underside of the leaves and leaving after itself the products of vital activity in the form of sticky sugary excretions. This becomes an excellent medium for the development of black fungus, which leads to the withering of the plant. Many diseases of zucchini in the open ground (with photos depicting the affected plants, you had the opportunity to see in this article) are distributed by these insects.

The whitefly can be washed off with water, carefully loosening soil after this. Sometimes you have to resort to spraying with the insecticide "Commander". Processing is carried out only after the harvest is harvested.

Throughout the season, we have to closely monitor the pests and diseases of courgettes that threaten plants. In time, the measures taken will help to save the planting and get a full harvest.