Diseases of zucchini in the open field and the fight against them photo

Many gardeners are faced with such a problem as diseases of zucchini in the open field and the fight against them, a photo will help identify the problem.

Zucchini suffer from viral or fungal pathologies, they are affected by various pests. An accurate understanding of the problem will help determine the choice of method, how to deal with it, how to save and protect the crop.

How to deal with zucchini diseases?

The most common diseases of zucchini, depending on the pathogen causing them, are fungal.The culprits of the diseases can cause the death of leaves, fruits or roots. Control methods common to all diseases: crop rotation, timely removal of debris and weeds from the territory of the site, destruction of the affected parts of the plant.

Favorable conditions for the development of diseases are nighttime temperature changes and increased humidity, for example, after rain or excessive watering. The source of the pathogen are affected plants and seeds. Insects contribute to the spread.

Anthracnose

Fungal diseases of squash and their treatment is the most common problem that occurs when growing a crop in open ground.

Zucchini anthracnose is a fungal disease caused by a fungus of the genus Colletotrichum. First of all, weak and mechanically damaged plants at any stage of development are affected. Anthracnose affects zucchini planted in soil with high acidity, with insufficient amounts of potash and phosphorus fertilizers.

Yellow or brown spots appear on the leaves with a dark brown or purple edging, which quickly grow first on the entire surface of the leaf plate, and then on the stem, flowers and fruits. Lesions deepen into the body of the plant and impede the movement of water and nutrients.

The stems and fruits are covered with weeping, slimy spots and begin to rot over time, and the leaves curl up. The fruits shrivel, acquire a bitter aftertaste. The defeat of the root zone leads to the death of the plant.

At the initial stage of development of anthracnose, shoots are sprayed with a 35% solution of colloidal sulfur, 1% solution of Bordeaux mixture (100 g of copper sulfate and quicklime are diluted in 10 liters of water), EM preparations.

Dig up the soil before sowing to reduce acidity with wood ash, dolomite flour or lime, apply fertilizers containing phosphorus and potassium.

Bacteriosis

Bacteriosis is of 2 types and manifests itself as either angular leaf spot or fruit vertex rot.

With angular spotting, the leaves turn white at first, it is not easy to determine why and why the leaves of zucchini turn white, since such damage develops with several more diseases of the culture. If in the future, instead of small white spots, angular brown spots appear, this is a bacteriosis.

The disease affects the plant at the stage of emergence of the cotyledons. At first, the spots become dark green, then brown, dry out, fail, forming holes between the veins of the leaf plate. Since the holes are limited by veins, they are angular in shape. Brown watery sores appear on the fruits, which lead to deformation of zucchini.

The struggle is to remove the affected parts of the culture. With minor lesions, the shoots are treated with a 1% Bordeaux mixture, a 0.4% solution of copper oxychloride. As a preventive measure, seed treatment with a 0.02% solution of zinc sulfate is used, in which the seeds are immersed for a day and then dried.

Another kind of disease is vertex bacteriosis of fruits. In this case, the tops of the fruits first turn yellow, then brown-brown spots appear on them. At the same time, the lower part can grow further. In the future, the fruits become glassy and rot.

It is impossible to save a plant from apical bacteriosis - it will have to be destroyed.

Sclerotinia white rot

The fungus can cause various putrefactive diseases of squash in the open field, it is much easier to identify the type of rot with a photo.

With white rot, or sclerotinia, a flaky white coating appears on the leaves of zucchini with black dots, which eventually spreads to fruits, antennae, cuttings and stems. They develop white colonies of the fungus - sclerotia, which soon turn black.

Sclerotia fall off and overwinter in the ground, and in the spring they are a source of infection. Damaged areas of the plant become covered with mucus, soften and rot. If the base of the stem rots, the plant dies.

Infection of plants contributes to an excess of nitrogen in the soil. Treatment consists in treating the affected areas on zucchini with crushed activated charcoal, wood ash or quicklime.

The following measures are taken to combat the pathogen:

Using warm water for irrigation.
Basic feeding with a mixture of 10 liters of water, 1 g of zinc sulfate, 2 g of copper sulfate, 10 g of urea.
In dry and hot weather, the affected organs of the plant are removed. The sections are sprinkled with crushed coal or washed with a 0.5% solution of copper sulfate.
As a top dressing, substances containing calcium are used: ground chicken egg shells, wood ash at the rate of 200 g of the substance per 1 m². Phosphate fertilizers are introduced.
The soil is irrigated with Fitolavin solution, and compost is added to restore microflora.

Gray mold botrytis

Another type of putrefactive mycosis is gray rot. At the same time, the greenery of the grass changes, the leaves become ill, the leaves, the ovary of fruits suffer. Most often, young vegetable ovaries are affected. The fruits become watery, like other affected tissues, get wet, soften, turn brown, covered with a gray coating with black dots.The spores of the pathogen persist in the soil for up to 2 years.

The causes that exacerbate the conditions and methods of infection with the disease are the same as with white rot. Ways to fight are also the same. The affected areas of the fruit can be powdered with a mixture of copper sulfate and chalk, combined in a ratio of 1: 2.

Basic rot

Root rot affects the plant, like top rot, in the phase of fruit formation and is manifested by rotting of the root system and neck. The affected tissue darkens and turns brown, becomes rotten and soft. The lower leaves turn yellow. Culture stops growing and withers, and eventually dies.

Root rot appears due to the frequent application of organic top dressing. Plants can be treated with biological preparations Trichodermin and Glycoladin, which contain fungal spores - antagonists of the rot pathogen.

Seeds 3 weeks before sowing can be treated with TMTD (Thiram) at the rate of 5-6 g/kg of seed. Infected plants are watered with a 0.1% solution of Previkur at the rate of 200-300 ml for each bush. In addition, solutions containing metalaxyl, mefenoxam are used.

Powdery mildew

Another fungal disease of zucchini is white powdery mildew. In this case, ailments are manifested by the appearance on the leaves, less often on the stem and cuttings, of small rounded white spots, sprinkled with powdery pollen - spores of the fungus.

Over time, the spots increase, merge with each other and cover the entire plant, as a result of which it turns yellow and dries out due to the impossibility of photosynthesis. In addition, the body of the fungus sucks nutritious juices from the culture, which leads to the impossibility of fruit formation. Mushroom overwinters on weeds.

Affected plants are sprayed with a solution of colloidal sulfur 35%, a solution of sodium phosphate 0.5%, a solution of isophrene 10% or powdered with ground sulfur at the rate of 300 g per 100 m².

Downy mildew downy mildew

Peronosporosis affects the leaves of zucchini at all stages of the growing season. First, yellow spots appear on the upper side of the leaves, which on the other side of the leaf are covered with gray-purple spores of the fungus.

The spots increase, merge with each other, which leads to browning and drying of the foliage. The disease progresses very quickly. Sometimes the outer side of the sheet is covered with a white coating. Despite the similar description, the treatment of downy mildew is somewhat different from the removal of powdery mildew.

Watering is completely stopped for the duration of treatment. He althy leaves are treated with a tank mixture, copper oxychloride solution, Metriam, a mixture of fungicides and growth stimulants. For prevention, the seeds are poured for 15 minutes with hot water (+50 ° C).

Black gourd mold

Black mold of cucurbits can appear on the leaves and other above-ground organs of squash. Outwardly, it manifests itself as small light brown spots, which eventually merge, turn into foci of necrosis, covered with black plaque - spores of the fungus from the genus Aspergillus.

The green parts of the plant turn yellow and dry out as a result of its vital activity, and the fruits stop developing, shrivel and rot. High humidity and large temperature fluctuations stimulate the course of the disease.

If a plant could get sick and not cure it, all the zucchini in the area get sick.

Fusarium wilt

Diseases and pests: Zucchini pests most often affect the aerial parts of plants. Fusarium is no exception. The first sign of this disease is yellowing and weakening of the upper leaves of the bush.

The stems turn brown at the bottom (basal part) and are covered with a pink or orange coating. Fusarium also affects the roots. As a result, within a few days the plant dries up and dies. On the cross section of the stems, you can see the browning of the veins.

In the initial stage of the lesion, you can dust the bush and the ground around it with wood ash, but this is of little effect.The struggle consists in improving the soil - sowing green manure plants, applying organic and mineral fertilizers, applying crop rotation, removing weeds, applying EM agents and calcium preparations.

How to deal with zucchini pests?

The appearance and number of pests is affected by air humidity and temperature, crop density, irrigation intensity and general care of the site and crops. The reasons for the appearance of insects are too dense planting, weedy beds, high humidity.

Melon aphid

Melon aphid first infects weeds, and then moves on to cultivated plants. Aphids gnaw on leaf plates from the underside, stems, ovary, flower petals. Affected organs curl up, dry out, flowers fall off. The growth and development of plants slows down, and then they die.Aphids can produce up to 20 generations per season. The pest overwinters on plant debris.

The method of prevention is timely weeding of seedlings, harvesting plant residues immediately after harvest, competent crop rotation.

To kill aphids, use 10% solutions of Karbofos or Trichlormetaphos-3, tobacco dust infusion (1 part of dust is infused with 10 parts of water and diluted with clean water in a ratio of 1: 3), yarrow infusion (1 kg of grass is infused for 10 l of water for 2 days).

Whitefly

Whitefly is a small white insect covered with powdery pollen. Both adults and larvae eat leaves and young shoots, suck the juice out of them, and also infect with various diseases. The feces of adult insects corrode the leaf plate, which leads to the appearance of black spots on it.

The defeat of zucchini is manifested by discoloration, twisting and death of the leaves, and later on the whole plant.

The most effective drugs against whiteflies: Aktara, Actellik, Double effect, Commander, Tanrek, Oberon and others. The products are diluted according to the instructions and sprayed on the plants and the soil around them at the frequency recommended by the manufacturers. Watering zucchini with insecticide solutions is more effective.

You can spray zucchini with onion or garlic infusion daily for a week.

Spider mite

The activity of the spider mite is very harmful. It strikes the undersides of the leaf plates, braids them with a thin cobweb. Yellow dots form in the affected areas, then the leaves turn completely yellow, acquire a marble pattern and dry out. With a large degree of damage, zucchini die. Ticks give during the season up to 15 generations, and hibernate in groups under plant debris and debris.

There are ways to get rid of the pest, the spider mite can be destroyed by the following means:

Spraying the leaves in hot weather. Water can be replaced with infusion of onion peel or garlic. To prepare tinctures, 200 g of raw materials are poured into 10 liters of water and kept for 2 days.
Spraying with 20% Chloroethanol solution.
Irrigation with Isophene solution 10%.
Spraying ground sulfur at the rate of 300 g per 100 m².

To improve the adhesive properties of solutions, 30 g of laundry soap is added to them.

Sprout Fly

Sprout fly larvae can be found on germinating seeds and seedlings. Gray flies have a body size of no more than 3-5 mm. The flight of insects begins in spring. They lay their eggs in places with high humidity, especially near manure.

Within a week, larvae appear from eggs, which destroy crops in 14 days. The larvae then pupate. During the warm season, 2-3 generations of sprout flies appear. Especially often larvae of germ flies on leaves can be found in cold summer.

As a preventive measure, manure must be carefully incorporated into the soil, plant residues removed, and watering regulated. In the spring, before the start of summer, Karbofos or Fufanon are introduced into the soil. The aerial part of the plant can be pollinated with wood ash, ground black pepper, and tobacco dust. For irrigation use the following solution: 200 g of table s alt and 10 liters of water.

Slugs

Slugs gnaw embryos in seeds, eat leaves on seedlings. Fixing on the stem, the mollusk gnaws through it, which leads to the death of most of the plant. Later, pests gnaw out the fruit ovaries or damage young squash, eating the pulp in them and even making moves.

In addition to reducing the yield, snails leave traces of mucus and other secretions on the affected area of the stem, leaf or fruit, thereby reducing the presentation of products. Once in the storage with the collected fruits, the slugs continue to harm, destroying the crop.

The easiest way to deal with shellfish is mechanical. They are harvested by hand or with the help of special traps. Traps are made from pieces of burlap or plywood and placed around the perimeter of the site. Protective grooves up to 30 cm wide are broken around the plantings and filled with needles, sand, sawdust, which hinder the progress of pests.

Use special preparations: lay out Metaldehyde granules (at the rate of 4 g per 1 m²), eating which leads to the death of slugs, spray the soil and plants with a solution of copper or iron sulfate, spray lime.