Causes of white spots on the leaves of zucchini

White spots on the leaves of squash are a sign of a disease common in pumpkin, they are clearly visible and cover the leaf surface in large quantities, and sometimes spread to the stem.

Causes of white spots on zucchini leaves

The main causes of white spotting

White spots and plaque on zucchini foliage and fruits have different pathogenesis, indicating damage to the fungus or attack by a harmful insect.

Powdery mildew

One of the common reasons why leaves of zucchini have turned white is a fungal disease – powdery mildew.

It appears in conditions of high humidity and at a low ambient temperature to 18 ° C and below.

The saturation of soils also favors the appearance soil with nitrogen-containing fertilizer complexes in the absence of regular watering.

False powdery mildew is accompanied by the appearance of yellow or brown oily fragments

After some time, the spots increase in diameter, they are gradually covered with a powdery coating that can spread to the stalk of the squash .

The infected foliage fades and dies. Damaged stems lose their elasticity, become lethargic and brittle.

With the appearance of powdery mildew at the fruiting stage, the ripening time of vegetables is reduced, but zucchini lose their gastronomic qualities and acquire a bitter or sour taste.

Spider mite

The attack of the spider mite on planting zucchini is associated with increased humidity when growing vegetables in greenhouse and greenhouse conditions, as well as thickening bushes.

The pest settles on the lower part of the foliage in a short space time it is surrounded by a thin web.

The spider mite has a small oblong body up to 0.4-0.6 m in size with a light green color.

When this pest is infected zucchini leaves are covered with white specks, which after some time are converted into spots. Later, it begins to turn yellow and dies over time.

With large damage, the plant dies due to disruption of the photosynthesis process.

A mass attack is observed in the summer from June to August, when the street is stable, warm weather.

Rot

Rot appears due to temperature changes

Often the leaves of the zucchini turn white due to a fungal disease called Gray Rot.

The disease appears with sudden changes in temperature at night and daytime .

Favorable factors that enhance its development are high humidity of the environment and soil and oversaturation of the soil with nitrogen, which contributes to the active growth of green mass and thickening of plantings.

More often P The appearance of gray rot occurs in the last days of May and the end of August.

Initially, it affects the squash leaves and ovaries, causing them to die. Spots cover the plaque, subsequently they become moistened, soften the structure of the vegetative parts of the vegetable culture, spreading to healthy specimens.

Mosaic

White mosaic also appears as white spots on the leaves of squash, they form a mosaic pattern

It is considered one of the dangerous diseases of the pumpkin family.

After a short amount of time, only veins remain green in the vegetable crop, the rest of the leaf burns out.

When hit by a mosaic sheet and not subject to deformation and not twisted zhuhnet.

Causes of occurrence: sharp changes in water temperature during irrigation and soil, as well as improper selection of predecessors.

Fungal disease leads to a delayed development of vegetable culture, fading of stems, foliage and fruits . Vegetables are obtained in a deformed shape, often with white stripes and growths.

Fight with chemicals

The use of chemicals in the fight against white spotting on leaves depends on the source of its appearance .

From the spider mite

From the spider mite use insecticides: Karbofos, Fitoverm, Actellik.

They kill the parasitic insect and effectively protect the plant for up to 2 weeks. With a massive lesion of squash plantings, it is recommended to treat the vegetable culture with insecticides in several approaches. It is not recommended to use insecticidal treatment on fruits.

From powdery mildew

To prevent fungal spores of powdery mildew from spreading, planting zucchini is treated with copper chloride (40 g is dissolved in 10 l water).

Also effective against the fungus are:

• copper sulfate (50 g per 10 l);
• Topaz (2 ml per 10 l of water );
• Phytosporin (5 g per 10 liters of water).

From gray rot

Fungicides will save you from the problem

In the fight against gray rot in zucchini, fungicidal preparations like Rovral and Bayleton are used, while fertilizing the vegetable culture with organic and prepared mineral complexes.

From mosaic

It is impossible to eliminate the viral white mosaic, because it is not treatable.

To prevent it from appearing, preventive measures are needed.

Alternative methods of treatment

Alternative means in the fight against the causes of white plaque and spots on zucchini, they are an effective alternative to chemistry.

From the spider mite

Effectively against the parasitic insect:

• laundry soap in solution (100 g per 10 l of water) for washing foliage;
• onion peel in infusion (500-700 g per 10 l of water is boiled and infused for 8-12 hours) for spraying ;
• garlic in infusion (5-6 garlic heads in 4-5 liters of water, insist 4 hours) for spraying;
• tobacco in infusion (40 g per 1 liter for 2 days) for spraying.

From powdery mildew

Folk remedies help to control powdery mildew:

• soda ash, on the basis of which they make working solution: mix 25 g of soda, 5 l of water and 1 tbsp. soap.Zucchini is sprayed with this composition, it is recommended to process it 2-3 times with an intermediate interval of 8-10 days;
• iodine (1 ml) in combination with milk (1 l) and water (9 l). The solution is sprayed on the affected areas with an interval of 14 days.

From gray rot

Milk whey helps to get rid of gray rot (1 liter of acidic milk product for 3 liters of water insist 3-4 hours). Used for spraying.

From the mosaic

It is problematic to cope with the white mosaic with folk remedies. The main measure against fungus is replacing soil.

Preventive measures

Preventive measures help prevent zucchini from being damaged by diseases and pests and avoid white spots and plaque on their leaves.

Basic preventive measures:

• regular weeding with careful removal of weeds;
• crop rotation with the correct selection of predecessors and a change of months planting zucchini every year;
• dressing vegetables with drugs that increase resistance to diseases and pests; maintaining the required moisture level in soil and the environment, especially in greenhouses and greenhouses;
• watering plantings with room temperature water;
• pre-sowing disinfecting treatment of seed material.