Zucchini or zucchini can be affected by various diseases that not only adversely affect their presentation, but also significantly reduce the yield of this crop. No less dangerous for her are some pests. To save your landing from such threats, it is important to know about them in advance.
List of zucchini diseases
Squash pathologies are fungal, viral and bacterial depending on the type of pathogen. These infections attack not only the surface of the leaves and the stem, but also the fruits themselves, so they lose their nutritional value. What pathologies do you need to protect your crop from? Let us consider it separately.
Anthracnose (coppers)
Why arises? This fungal disease is caused by a fungus of the genus Colletotrichum. It mainly affects weak and mechanically damaged plants at any stage of development. Copperwort is more commonly observed in greenhouse and greenhouse crops, but does not bypass even zucchini in the open ground. Favorable conditions for its development:
- soil with high acidity, which is fertilized with an insufficient amount of potassium and phosphorus fertilizing;
- watering in the heat;
- high humidity of air and soil;
- poor cleaning of the site from crop residues.
Signs. Anthracnose attacks all organs of the vegetable:
- The leaf plate is covered with rounded yellow or brown spots, which have a dark brown or purple border. Over time, they grow and spread to the rest of the plant, and the leaves curl and become spotty.
- Brown impressions with pink bloom form on the stems, flowers and fruits.
- Gradually, lesions deepen into the thickness of the plant, blocking the movement of water and nutrients. Against this background, the fruits gradually wrinkle, acquire a bitter aftertaste and begin to rot.
- If the disease affects the root part of the seedlings, then they are likely to die.
Control measures. At the initial stage of the development of copperfish, leaves can be sprayed with a 35% solution of colloidal sulfur (40-100 g per 10 l of water) or a 1% solution of Bordeaux mixture (100 g of copper sulfate and quicklime per 10 l). In severe lesions, the leaves should be watered once every 2 weeks with biological products for squash or other pumpkin (for example, Fitosporin). With mass infection, plants will have to be destroyed. If seedlings grow in a greenhouse, then after harvesting it will need to be disinfected with bleach (200 g per 10 liters of water).
Anthracnose can be transmitted through seeds, therefore, before planting in the soil, seedlings should be carefully selected. The seed itself can be treated with a 0.2% solution of boron, copper and manganese. If necessary, it is equally important to lower the acidity of the soil by digging it with wood ash, dolomite flour or lime, and also to make fertilizers containing phosphorus and potassium.
Ascochitosis
Why arises? Ascochitosis is a consequence of excessive moisture in the soil and air at low temperatures. The causative agents are fungi of the genus Ascochyta. The infection remains even on crop residues, and zucchini rot.
Signs. Fungal disease affects all aerial parts of the plant. Light black spots with pronounced black dots - mushroom pycnids appear on the stems and leaf plate. Affected areas quickly blacken, become soft and dry, and the plant dies. As a rule, ascochitosis affects the base and branching of the stems, due to which they lose their elasticity and break. It is possible that infection of the root part of the vegetable in conditions of excessive soil moisture.
Control measures. The affected areas should be powdered with copper-chalk powder (a mixture of chalk and copper sulfate 1: 1). In addition, they need to be treated with powdered charcoal to dry the affected tissue and prevent the spread of infection.
Bacteriosis
Why arises? It is considered the biggest threat to zucchini and other pumpkin crops, since it irreversibly affects not only parts of the plant, but also the root crops themselves. The causative agent of the pathology is carried by insects, drops of water, plant debris. In this case, the infection persists on the seeds and tissues of plants. Such conditions contribute to the development of bacteriosis:
- sharp changes in temperature during the day and night;
- high humidity of the soil and air;
- planting seeds without pre-treatment;
- poor harvesting after harvesting.
Signs. Depend on the type of bacteriosis:
- Angular leaf spot. It makes itself known even at the stage of the appearance of cotyledons. The spots on the leaves undergo such a transformation - they become dark green, and after brown, they dry out and fall through, forming holes of an angular shape between the veins. The fruits are covered with violent watery sores, due to which they are deformed.
- Apex bacteriosis of the fruit. At the tip of the zucchini, they first turn yellow, and then become covered with brown-brown spots. The base continues to grow further. Ultimately, the roots become vitreous and rot.
Control measures. Before planting, the seeds must be soaked for a day in a 0.2% zinc sulfate solution, and then dried thoroughly. They can be treated with Fitosporin-M or another fungicide. With this composition, it is also worth watering the garden 5 days before planting seeds or seedlings. In order to prevent and at the slightest suspicion of bacteriosis, the shoots should be treated with a 1% Bordeaux mixture or 0.4% copper chloride solution. However, it is important to interrupt the spraying of the fruit 15 days before harvesting. If there is serious damage, it is impossible to help the plant, so it will have to be eradicated and destroyed.
White rot (sclerotinia)
Why arises? The source of infection are sclerotia, which fall from plants and winter in the ground, and in the spring they attack the plant. It is especially susceptible to disease at the fruiting stage. The following factors contribute to infection:
- excess nitrogen in the soil in combination with a low ambient temperature;
- overly thickened plantings;
- sudden changes in temperature;
- an excess of nitrogen fertilizing.
Zucchini can become infected with sclerotinia through air currents, as well as due to the ingress of pieces of mycelium in the stomata and mechanically damaged places.
Signs. The fungus affects all parts of the plant - fruits, mustaches, leaves and their petioles, stems and roots. Initially, a flaky white coating forms on them, and then black dots appear - fungal spores. The affected parts become soft, become covered with mucus, soften, rot and die. As a result, the fruiting of the plant is disrupted.
Control measures. If on the bushes there are symptoms of white rot, in particular, a white coating on the leaves is noticed, it is necessary to begin the fight against the pathogen. The following measures will help in this matter:
- powdering the affected areas with a mixture of crushed chalk and copper sulfate powder (1: 1);
- sprinkle the surface of the affected areas with crushed coal to dry them and stop the spread of infection;
- if zucchini is infected in a greenhouse, reduce air humidity and regularly ventilate the room to prevent the mass spread of sclerotia;
- with a strong spread of white rot in dry and hot weather, remove the leaves of the plant, and sprinkle the places of cuts with powdered charcoal or wipe with a 0.5% solution of copper sulfate;
- water the plant with warm water;
- carry out radical top dressing (1 g of zinc sulfate, 2 g of copper sulfate and 10 g of urea per 10 liters of water), as well as phosphate fertilizers and top dressings with calcium content (ground eggshell or wood ash at a rate of 200 g per 1 sq. m plot);
- water the soil with a solution of Fitolavin, and also make compost to maintain microflora.
If the fruits are covered with white coating, they should not be eaten. They need to be separated from the rest of the crop and destroyed so that sclerotia can not spread to healthy areas.
In order to prevent white rot, the bushes can be sprayed with a composition of 1 g of copper sulfate, 1 g of zinc sulfate and 0.5 tbsp. l urea in 10 liters of water.
Root rot
Why arises? It is a consequence of excessive introduction of organic fertilizing. It also arises due to sudden changes in temperature, weakening of the vegetable crop, irrigation with cold water (up to 20 ° C) or a clogged bed.
Signs. The disease affects the plant at the stage of fruit formation. In this case, the root system, stems and necks rot, and the affected tissues darken and brown, become rotten and soft. The lower leaf plate is covered with yellowness. All this stops the growth of the plant, it fades and dies over time.
Control measures. For preventive purposes, 3 weeks before planting, seeds can be treated with Tiram (5-7 g per 1 kg of seed). If there is suspicion of the development of basal rot, it is worth adding soil to the stem for the formation of new roots. In addition, you need to water the plant with 0.1% Previkur solution (200-300 ml for each bush). You can also use solutions containing metalaxyl (mefenoxam). Infected plants will have to be removed from the garden and burned, and the soil treated with copper sulfate.
Yellow mosaic
Why arises? This is not a fungal, but a dangerous viral disease that is extremely stable in the external environment and easily spreads throughout the garden. The carriers of the virus are pests - aphids, thrips and whiteflies. In addition, the disease is transmitted through infected seeds, soil and plant debris. Mosaic causative agents can remain in the ground for several years.
Signs. With the development of the mosaic, star-shaped white-yellow spots appear on the leaves, which gradually grow, causing twisting of the young upper leaves first, and then the lower ones. White and yellow stripes appear on the affected fruits.
Methods of struggle. The disease is not treatable, so the whole planting will have to be pulled out and burned, and the infected soil replaced with new ones to get rid of the mosaic pathogens. To prevent its development, you need to use the seeds of only uninfected plants, and before planting, disinfect them by soaking for 60 minutes in a 15% trisodium phosphate solution.
Fusarium wilt (fusarium)
Why arises? It is provoked by soil fungi, which can affect the plant at any stage of development. Pathogens penetrate the root system of the vegetable from the soil, lead active life in the vessels that conduct it, and gradually grow.
Signs. Yellowing and weakening of the upper leaves of the bush speaks of fusarium, first of all. In the basal part, the stems are browned, covered with pink or orange bloom and rot. On their cross-section, one can notice the browning of the veins. The disease and the root system are affected, due to which the plant dries and dies within a few days.
Control measures. If pathology is detected at the initial stage of development, then the bush and the ground around it must be dusted with wood ash. However, this will not be enough. In order to get rid of Fusarium precisely, it is necessary to improve the soil - to plant green manure, to add organic and mineral fertilizers, to remove weeds, to add EM products and calcium preparations.
Powdery mildew
Why arises? A fungal disease whose pathogens hibernate on plant debris such as plantain, sow thistle, etc. During the growing season, they spread to vegetable crops, which are especially promoted by such factors as winds, high air humidity, rare watering, and excessive fertilizing with nitrogen fertilizers.
Signs. They often appear on leaves and to a lesser extent on stems and petioles. Powdery mildew is manifested by rounded white spots of small sizes, which are called flour coating. Gradually they increase in size and cover the entire sheet plate with a powdery white coating, which subsequently turns yellow and dries. The tops themselves curl and dry out due to a violation of the photosynthesis process. This is the sporulation of the fungus, which absorbs all nutrient juices from the culture and makes the formation of full-fledged fruits with a pleasant taste impossible.
On heavily affected foliage, fruiting bodies (cleistocarpies) form, which infect the plant next year.
Control measures. So that white powdery mildew does not ruin the entire crop and does not threaten future plantings, at the first defeat, the planting should be sprayed with this means:
- 35% colloidal sulfur solution;
- 0.5% sodium phosphate solution;
- 10% isofrene solution.
Landings can be treated every 80 days with 80% sulfur powder (400 g per 100 sq. M) or dusted with ground sulfur (300 g per 100 sq. M), which should be applied to the affected areas with a fleece. The final processing should be done 10 days before harvest. If there are specimens with severe lesions, on a sunny day (at a temperature not lower than 23 ° C) they must be immediately cut off and the plant pollinated with ground sulfur. If the weather is cloudy, it is better to use the same solution of colloidal sulfur (40 g per 10 liters of water) for processing.
To protect the zucchini from powdery mildew, it can be sprayed with mullein infusion. To prepare it, 1 kg of raw material must be filled with 3 liters of water, left for 3 days, filtered and diluted with water at the rate of 1 liter of infusion per 3 liters of water.
Downy mildew (peronosporosis)
Why arises? It affects zucchini at all stages of their growing season also due to the vital activity of fungi. Has the same description as white flour dew.
Signs. Leaves on the outside are covered with yellow-green spots, and on the bottom - gray-purple spores of the fungus. Gradually, the spots expand their boundaries and unite, causing drilling and drying of the tops. In some cases, the outer part of the leaf plate is also coated with white coating. The disease progresses rather quickly.
Control measures. For disinfection, the seeds before planting should be soaked for 20 minutes in a 1% potassium permanganate solution or for 15 minutes in hot water (+ 50 ° C). If the disease manifests itself, then at the time of treatment you need to stop watering the plant. Sick specimens can be treated with a 1% Bordeaux mixture, Topaz or Oksikhom. Unscathed leaves should be fed with a tank mixture, a solution of copper chloroxide, a mixture of fungicides and growth stimulants.
Black rot (mold)
Why arises? It is provoked by spores of the Aspergillus fungus. The development of black rot spurs violation of the rules of agricultural technology, high humidity and severe temperature changes.
Signs. The disease manifests itself on the leaves and other terrestrial parts of zucchini. The plant is covered with small light brown spots that can stick together and form foci of necrosis. As a result, they are covered with a black coating - mushroom spores. For this reason, the tops turn yellow and dry, and the fruits lag behind in development, wrinkle and rot.
Control measures. If you do not respond in a timely manner to the appearance of black rot, then soon all zucchini in the area may become ill. Sick specimens must be removed from the garden and burned.
Gray Rot (Botritis)
Why arises? It is a variety of putrefactive mycosis. The spores of the fungus that provoke it can be on the green of the weed grass and transferred when polluted by insects from one flower to another, which increases the prevalence of the disease. Such factors contribute to this:
- adverse weather conditions - sudden changes in temperature, excessive humidity of air and soil;
- poor care (irregular watering, the use of cold water from a well or water supply, watering after sunset, an excess of nitrogen fertilizers or a lack of trace elements).
Signs. Botritis often affects young zucchini. From it suffer leaflets and fruit ovaries. They acquire a watery consistency, turn brown and gradually become covered with a gray coating. Black dots also appear on them - fungal spores that are able to persist in the soil for up to 2 years.
Control measures. Sulfur rot will not occur if timely weed removal near the vegetable is observed, agricultural regulations are followed, phosphoric fertilizers and foliar fertilizers are added, and zucchini every 10 days. If affected areas are found, they should be dusted with a mixture of copper sulfate and ground chalk (1: 2). Planting should also be sprayed with a solution of 10 g of urea, 2 g of copper sulphate and 1 g of zinc sulfate per 10 l of water. It is desirable to remove diseased ovaries and fruits, and then destroy.
Olive spotting
Why arises? A fungal disease that affects seedlings, leaves and stems due to high humidity. In hot time, it appears at the end of the growing season of zucchini, when cool nights with a considerable amount of dew come. In the greenhouse, the pathogen spreads with drops of condensed moisture, and in the open ground - by the wind, during irrigation, or in the rain. The infection persists for a long time in the soil and on plant debris.
Olive spotting is actively progressing in the conditions of sharp temperature drops and cool rainy summers.
Signs. Pathology affects all terrestrial parts of the plant. Brownish spots of various shapes with a lighter border and a lighter center appear on the leaves. On petioles of leaves and shoots ulcers are formed, which are covered with an olive coating. As for the fruits, they also appear watery small ulcers, which rapidly expand in size and lead to cracking of the skin. As a result, zucchini bend, and young ovaries die.
Control measures. With the development of olive spotting, the planting should be treated with 1% Borodsky liquid (100 g of copper sulfate and the same amount of lime), with a suspension of 80% Kuprozan.
List of zucchini pests
For a vegetable crop, the danger is not only the listed diseases, but also some pests. Why they attack landing and how to get rid of them, we will understand further.
Slugs and garden snails
Description. These are gastropod mollusks, reaching a length of 2-3 cm to 10 cm. Their body is thick, vermiform and completely covered with mucus. Snails have the same description, only their body is under the sink. These pests in sunny and dry weather hide in damp and secluded places, but with the onset of darkness creep out and attack vegetable crops in the garden.
Signs of defeat. Mollusks gnaw seeds in seeds, eat leaflets on seedlings and gnaw stems, causing the death of the whole plant. When young zucchini appear, they also eat the flesh in them and even thread moves. They not only reduce productivity, but also spoil the presentation of vegetables, leaving behind mucus and other secretions.
Control measures. The primitive method of combating mollusks is mechanical. It involves the collection of mollusks by hand or using special traps made from pieces of burlap or plywood and located around the perimeter of the site. Around the landings, you can also dig protective grooves up to 30 cm wide and fill them with needles, sand or sawdust in order to prevent the progress of pests. Against them, you can also use granules of Metaldehyde (4 g per 1 sq. M), a solution of copper or iron sulfate, lime.
Sprout fly
Description. These are small flies of gray color with a dark longitudinal line on the belly. In length they reach 3-5 mm. Flies lay eggs under lumps of soil. After 5-10 days, white larvae already narrowed in front of them, with teeth on the end of the body and up to 7 mm long, which can destroy all crops in 2 weeks, especially in cold summers. Then the larvae pupate. During the warm season, 2-3 generations of insects may appear.
Signs of defeat. Pests can be found on the seedlings of the plant. The larvae destroy the germinating seeds, gnaw the submucosal knee and penetrate the stem. As a result, a young plant may die.
Control measures. If you dig a deep soil in the fall with the introduction and careful incorporation of manure, this will be an excellent prevention against flies. In the spring, before the start of the summer season, Karbofos or Fufanon should be introduced into the soil. Seedlings can be pollinated with wood ash, ground black pepper or tobacco dust. For irrigation, a saline solution (200 g per 10 liters of water) is suitable.
Gourd aphids
Description. Aphids are small insects (3 mm) that not only gnaw leaves, young shoots and buds, but also carry dangerous infections. Female aphids are wingless, have an oval body 1.25-2.1 mm long, and differ in dark green or black color. Larvae are yellow or green, with or without wings. The insect reproduces asexually and in the season gives 14-20 generations.
Aphid develops on weeds, where it hibernates, but with the advent of spring and heating of the air to + 12 ° C, it migrates to pumpkin plants, including zucchini. The optimum temperature for her life is + 16 ... + 22 ° C. Colonies of adult pests and their larvae settle on the bottom of leaves, shoots, ovaries and flowers.
Signs of defeat. Melon aphids eat green tops, resulting in shoots, leaves and flowers turn yellow and curl, and then dry and fall. With a large invasion of pests, flowers are showered from the bush. The plant lags in growth, and then dies.
Control measures. In order to prevent the aphid invasion, it is worth planting the following crops near the garden bed with zucchini:
- spicy plants (mint, coriander, fennel);
- flowers (lavender, marigolds);
- garlic, onion, mustard, basil.
You can also scare away pests from zucchini with a soap solution (100 g per 10 l of water) and dusting with sulfur powder.
If a small number of pests has already settled on the plant, in the fight against them, you can use gentle folk remedies:
- Tobacco infusion. To prepare it, 1 part of the raw material must be filled with 10 parts of water and left for a day. Dilute the composition with water in a ratio of 1: 3 and use it for leaf treatment.
- Yarrow infusion. Within 2 weeks, 1 kg of raw materials should be infused in 10 liters of water, and then used as directed.
Sick plants can be treated with such an effective microbiological agent as Bitoxibacillin. It must be prepared a few minutes before use. For this, the substance must be diluted with water from a ratio of 80-100 g per 10 liters of water. You can use the composition to treat the plant every 10 days. Among other drugs, it is also worth highlighting a 10% solution of Karbofos (60 g per 10 l of water) or Trichloromethafos-3 (50-100 g per 10 l of water).
Whitefly
Description. This is a polyphagous small insect of white or slightly yellowish color, the body of which is covered with powdery pollen and has a length of up to 2 mm. Outwardly, it resembles a moth. Adult individuals and larvae infect zucchini in June, settling below the leaf plate. They eat leaflets and young shoots, sucking out nutritious juices from them and at the same time infecting them with various diseases.
Signs of defeat. Insects first hit young shoots (leaves). They can be easily recognized by the bright spots that appear on the tops of the tops. In the process of life, the larvae secrete a sticky mass, which helps to tighten the leaves, prevents them from developing and serves as a favorable environment for the development of fungi. Adult insects corrode the plant and leave feces behind, so black spots appear on it. As a result, the affected specimens become discolored, curled and gradually fade. The buds are deformed, dry and fall off.
Control measures. To prevent the death of the plant, it can be sprayed with infusion of garlic or tobacco (you can add liquid soap) every 3 days. Leaves should also be sprayed with settled water. With a strong invasion of whiteflies, the bushes and the soil around them can be watered with insecticide solutions. Such drugs are effective:
- Actara;
- Actellik;
- Double effect;
- Commander
- Tanrek;
- Oberon.
After watering, it is worthwhile to loosen the soil.
Spider mite
Description. It is a sucking pest having an oval-oblong body 0.3-0.4 mm long. The eggs are spherical, at first they have a greenish transparent color, but then it stops unclear. Ticks winter in groups under plant debris, debris, and even in the surface soil layer at a depth of 30-60 mm. Most often appear in June and settle on the underside of pumpkin leaves. Egg larvae emerge within 5-7 days. During the season, ticks give up to 15 generations, and it takes 10-28 days to develop each of them.
Signs of defeat. Ticks attack the undersides of leaves and leave a thin spider web. Yellow spots appear at the lesion sites, which gradually spread to all leaves and lead to their drying out. In severe cases, zucchini die.
Control measures. To get rid of spider mites, against them you can apply the following measures:
- spray the leaves in the heat with an infusion of garlic or onion peel (pour 200 g of raw materials into 10 liters of water and leave for 2 days);
- sprinkle with infusion of black pepper (chop capsicum, pour 50 g of 10 l of water) with the addition of liquid soap (1 tbsp.) and wood ash (3 tbsp.);
The composition must be infused for a day, and then strain and use to process zucchini every 7-10 days.
- spray with a 20% solution of Chlorethanol (20 g per 10 liters of water) or irrigate with a 10% solution of Isophene (60 g per 10 liters of water);
- spray ground sulfur at a rate of 300 g per 100 square meters. m
To improve the adhesive properties of any solution, 30 g of grated laundry soap can be added to it.
Protection of squash from diseases and pests
To protect zucchini from all of these threats, it is important to adhere to the following preventative measures:
- observe crop rotation (do not plant zucchini in the area on which related pumpkin crops grew last season);
In the same place, zucchini can be sown once every 3-4 years.
- remove garbage, weeds and plant debris from the site in a timely manner;
- replace contaminated soil in greenhouses;
- thoroughly prepare the soil before planting so that it is enriched with all the nutrients (humus, peat, wood ash, compost, etc.);
- carefully choose seedlings for planting in the ground;
- from time to time to inspect the crops and timely destroy the affected parts of the plant, as well as remove diseased specimens from the garden;
- timely water the culture with settled water at a comfortable temperature;
- introduce fertilizers and fertilizing to maintain the immunity of the plant.
Proper agricultural technology and adherence to prevention will allow you to harvest zucchini up to the coldest. If the plant shows signs of damage, you need to respond to them in a timely manner and take all steps to improve your garden.