Even the most unpretentious crops require care, and gardeners and gardeners have to put in a lot of effort to grow a good crop. A lot of trouble for summer residents is caused by diseases of zucchini, and pests also annoy. To deal with them, you need to know the enemy in person, that is, you should study in detail what can threaten plants and how to deal with it.
Causes of disease development
The source of infection are usually fungi and viruses. As long as they are in the soil, the crop will suffer from year to year. All pumpkin crops are susceptible to infections, and zucchini is the most painful among them. Diseases of leaves, fruits and other parts of these plants are observed, as a rule, in cold and wet weather.
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 soil moisture, watering too cold water, etc. Gooda preventive measure is the timely application of fertilizers in compliance with dosages, maintaining the required humidity, and weed control. In closed greenhouses, for the purpose of prevention, it is recommended to disinfect with a bleach solution. It is necessary to immediately respond to the signs of any disease of zucchini and begin their treatment without delay.
Anthracnose
All terrestrial parts of the plant suffer from it. This disease usually begins with the formation of rounded yellow-brown spots on the leaves, which gradually pass to the stems and fruits, where they acquire an oblong shape. Over time, the area of \u200b\u200bthe affected areas increases, a mucous coating appears on them. As a result, the leaves dry up, and the fruits shrivel, acquire a bitter taste and rot. The appearance of signs of anthracnose on the basal part of the plant is a clear signal that the plant is dying. Excessive humidity contributes to the development of the disease, as well as watering during the hot time of the day.
More often anthracosis affects crops grown in greenhouses and hotbeds, although the pathogens of almost any zucchini disease in the open field (with a photo of plants affected by this disease can be found below) also feel good. Infection occurs throughout the growing season.
Pathogenic microorganisms can persist on a diseased plant for a long time, overwintering on its remains. The fight against infection comes down to the careful selection of seedlings and dressing the seeds. In addition, you must immediatelyremove all affected plants and then disinfect the greenhouse. Bordeaux fluid or colloidal sulfur helps to cope with the disease.
White rot
It covers the stems, leaves of the plant with a dense coating of white. These are the fruiting bodies of the sclerotia fungus, which is the causative agent of this zucchini disease (the fungus feels equally good in open and protected ground). Damaged tissues of the plant soften, the leaves dry up, and the fruits turn into a mushy mass. The disease spreads in cold and wet weather, especially if the plantings are heavily thickened. Zucchini is more susceptible to it during the fruiting period. 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.
You can get rid of white rot only by completely destroying the affected parts of the plant, sprinkling the cut with charcoal or wiping with a half-percent solution of copper sulphate. Timely cleaning of weeds, the use of warm water for irrigation, foliar top dressing, including copper sulfate, zinc sulfate and urea at the rate of 2 g, 1 g and 10 g, respectively, for every 10 liters of water, will help prevent the disease. Stem sections where only signs of white rot are noticed can be rubbed with a piece of cotton wool and sprinkled with crushed chalk or coal.
Grey Rot
Usually occurs on young ovaries, then moving to the leaves. Affected partsplants become watery, soften and covered with a gray coating. Under the film, zucchini suffer from this rot much more often. Diseases in the open are rampant, as a rule, only during prolonged rains or in cold weather.
The causative agent of gray mold is the main source of infection. It can survive in soil for up to two years. The spread of the disease is also facilitated by insects that carry spores of the fungus from one plant to another.
It is possible to prevent gray rot, like all diseases of zucchini, only by observing the rules of crop rotation, destroying weeds in a timely manner and making the necessary feeding. Affected ovaries and fading leaves found on the plant should be removed immediately.
Root rot
Most often this disease occurs in protected ground. It manifests itself in the fact that the roots begin to darken, soften, and the stem gradually turns brown. The lower leaves turn yellow and wilt. 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 too early planting, sudden changes in temperature, the use of cold water for irrigation, excess moisture in the soil. This and other types of rot are quite often diseases that affect zucchini. The fight against them is carried out in approximately the same way and consists in observing agricultural technology, disinfecting the soil, maintaining a certain soil moisture.
Powdery mildew
This disease first affects the leaves of the plant. Spots of loose grayish plaque form on them, which aftermerge for some time, covering the stems. This is the sporulation 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 cleistocarps are able to 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 until the first signs of the disease appear, it takes about 3-4 days.
Zucchini most suffer from powdery mildew when there are sharp fluctuations in air humidity, with an excess of nitrogen fertilizers, insufficient watering.
You can avoid this disease if weed weeds in a timely manner, after harvesting, remove all plant residues and dig the soil deep. At the first signs of fungal infection, the plant should be treated with any of the following drugs:
- Gray colloidal - 40 to 100 g of sulfaride per 10 liters of water for treatment in protected ground.
- Grey ground.
- "Isophene" (for greenhouses - 60 g per 10 liters of water).
- Infusion of mullein. It is prepared in the following way: 1 kg of manure must be poured with water (3 l) and left to infuse for 3 days. After that, the solution is filtered and diluted with water (1: 3) before processing.
- Gardeners often use ordinary potassium permanganate for spraying - 1.5 g of potassium permanganate per 10 liters of water.
Peronosporosis
This disease affects zucchini at any age. First on the leavesrounded spots of yellow-green color appear, which gradually become brown. Soon they begin to dry out and crumble. Sporulation sites are located on the underside of the leaf and are a purple bloom. The disease develops during a period of heavy dew, fog, when the humidity is especially high. Its causative agent can persist in the soil for several years.
It is possible to cope with the disease only by disinfecting or completely replacing the soil. One of the preventive measures is frequent ventilation of the greenhouse or greenhouse.
Ascochitosis
The pathogen affects the leaves and stems of the plant. At first, grayish spots form on them, which soon become covered with black dots. Infection begins, as a rule, from the lower leaves, which receive the least amount of light, and gradually moves to the upper ones. The crop suffers significantly from this disease that affects zucchini. By the end of the season, few fruits remain - infected with a fungus, they quickly dry out and turn black. The causes of the spread of infection are usually sudden changes in temperature, high humidity and excessive planting density.
You can get rid of a fungal infection by eliminating excessive watering, it is equally important to get rid of affected plants in a timely manner. It is enough to powder small foci of the disease with chalk powder mixed with copper sulphate in a ratio of 1: 1. This measure will prevent the spread of infection.
Black mold
On the leaves, you can first notice small rusty spots, whichover time, they turn into a dark coating. These are fungal spores. Gradually, the leaf blade under the stain dries up and crumbles, causing holes to appear on it. Fruit development stops. You can get rid of this disease of zucchini only by completely burning the affected plants.
Fusarium wilt
Soil fungus, which is the causative agent of the disease, penetrates the root system, growing in the vessels of the plant. As a result of this, the stem rots at the very base. The leaves become stained, the plant withers, breaks and dies. Only a complete replacement of the soil will help to cope with the problem. For the purpose of prevention, one should strictly observe the rules of agricultural technology and destroy weeds on the site in a timely manner.
Bacteriosis
The onset of the disease is characterized by the appearance of brown sores on the cotyledons and on true leaves. They also occur on fruits (only small in size and brown in color), leading to their curvature. Bacteriosis can persist for a long time on plant debris and on seeds. It begins to progress with sudden changes in temperature and excessive humidity. The spread of the disease is facilitated by insects, water droplets and particles of infected plants. The crop is seriously affected by this disease of zucchini. Measures to combat it necessarily include the treatment of seeds with zinc sulfate. They are placed in a 0.02% solution for a day, then slightly dried. Plants at the first signs of bacteriosis are treated with Bordeaux mixture (10 g of lime and copper sulphate each), and for prophylactic purposes - chlorine oxidecopper.
Viral diseases
Most often, zucchini suffer from cucumber and pumpkin mosaic. In this case, mainly leaves are affected.
Cucumber mosaic appears as small yellow-green spots. After some time, the leaves curl, and tubercles form between the veins. Plant growth slows down, and they practically do not produce a crop. Reservoirs of infection are perennial weeds - in their roots, the virus tolerates winter very well. It is not transmitted by seeds. For this reason, the whole fight comes down to the destruction of weeds.
In the pumpkin mosaic, the leaves also first become covered with light green spots. But then the ends of the veins begin to stand out along the edges, since the growth of the leaf blade slows down sharply. Its flesh falls out completely in places. The virus that causes this disease is seed-borne. It is able to remain in them for more than one year. Before planting, it is recommended to warm the seeds at a temperature of 50–60 ⁰С for three days.
Insect pests
Not only diseases of zucchini (in the open field), the fight against which requires considerable effort, bring a lot of trouble to gardeners. Rodents often eat seeds, shoots suffer from wireworms and bears. However, insects cause the most damage.
Melon aphid
Its larvae spend the winter on the remains of plants and form entire colonies with the onset of spring. It reproduces very quickly, giving offspring up to 20 times per season. By summer, aphids have wings, and, having the ability to move even faster,sucks nutritious juices from zucchini, damaging leaves and stems. The affected parts of the plant gradually dry out and deform. If we also take into account what diseases of zucchini the aphid suffers, then it will immediately become clear that the fight against it should be serious. To prevent the invasion of this insect, the destruction of all plant residues after harvesting and careful digging of the soil helps. If an aphid is found, an infusion of hot peppers will help get rid of it. It is prepared as follows: pepper, ground into powder (30 g), liquid soap (1 tablespoon) and wood ash (3 tablespoons) are mixed. The resulting mixture is diluted in 10 liters of water, insisted for a day, then, after filtering, they begin to spray the affected plants. Decoctions and infusions from potato tops, onion peels, and tobacco also help well.
Spider mite
These rather small insects (less than 0.4 mm in size) can cause irreparable damage to crops. They populate plants as soon as warm days come, settling on the underside of young leaves and feeding on cell sap. In the same place, it lays eggs, from which larvae appear after a week. The damaged leaf becomes covered with light dots, then becomes marbled and dries out.
The fight against this pest consists in burning all the remains of vegetation after harvesting and deep digging of the soil. If a tick is found on zucchini, spraying with various means can be practiced. Onion infusion is especially effectivehusks. A bucket half-filled with it is poured to the top with boiling water and insisted for 24 hours. Then filter and dilute with water in a ratio of 1:2. Used for spraying and infusions of potato tops, dope ordinary. In order for the solution to stick to the surface of the sheet, 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 behind waste products in the form of sticky sugary secretions. This becomes an excellent environment for the development of soot fungus, which leads to the wilting of the plant. Many diseases of squash in the open field (with a photo depicting the affected plants, you had the opportunity to familiarize yourself in this article) are spread by these insects.
Whitefly can be washed off with water, after carefully loosening the soil. Sometimes you have to resort to spraying with the insecticide "Commander". Processing is carried out only after the harvest.
Throughout the season, you have to carefully monitor which pests and diseases of zucchini threaten plants. Measures taken in time will help to save plantings and get a full harvest.
