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The spots on the leaves of violets can appear for different reasons and have different consequences. Examine the sheet carefully to understand the nature of the lesion, use a magnifying glass. You can take a picture of the spot and then maximize it in a graphics editor. The presence of black dots on the spot can indicate the appearance of spores of parasitic fungi, and small dots with an increase can immediately be identified as insect bites, sometimes you can even see pests on leaves with egg-laying spots, a web of the corresponding type of mites, etc.
If direct sunlight fell on the violet for a long period of time, then yellow rounded spots appear on the leaves - burns. The fleshy violet leaf is simply boiled in the sun, it softens, in the center the spot turns light brown, the same spots can appear on the flowers. Sunburns are easy to distinguish - they always appear on the side of the outlet that was facing the sun after a sunny day. All burnt leaves must be removed without fail, as the cooked leaf cells will begin to decompose and become a source of infection. The violet will lose its decorative effect, and yet this is not critical, the variety will remain.
The best places for Saintpaulias are in the north, northwest and northeast windows. If there are no such in the apartment, then the glass must be closed from early spring with a suitable transparent material: a special mirror film, a thin translucent cloth or paper, sometimes a small mosquito net is enough.
Spots of gray-beige color, small and covering almost the entire leaf, in the form of curls, blots, pea stripes along the edge of the leaf. Over time, due to the loss of chlorophyll, the leaf tissue becomes thinner, but does not rot. The reason for the appearance of the spots is that the violet was blown hard by a draft.
In the summer, when the apartment is hot, it seems that an open window or air conditioner will not lead to hypothermia, but a draft causes severe stress in violets, which leads to the manifestation of a disease of probably viral origin. The appearance of the outlet becomes sloppy, dirty, but nothing can be done, you have to wait until new leaves grow. There is no danger of contamination of other plants.
Dark spots along the edge of old leaves of the lower row, arise from a lack of nutrition, a sign of a lack of potassium. If the violet was not transplanted for a long time, the earthen mixture becomes alkalized, which prevents the absorption of potassium and some trace elements, even if fertilizers are applied during watering. The leaves of the lower row become light, almost yellow - also a sign of lack of nutrition.
The violet must be carefully removed from the pot when the top layer of the earthen mixture dries. Using a fork, try to remove the upper strongly alkalized layer by tapping it and tilting the plant, try to remove the old earth from the rest of the coma, as if by combing it, trying not to damage the roots.
Replace the old drainage, preferably with sphagnum moss (gives an acidic reaction). Remove the bottom layer of yellowed leaves and sprinkle with crushed coal. You can make a bandage of sphagnum moss soaked in a weak solution of potassium permanganate. Then transplant the plant into a slightly larger pot (1-1.5 cm). The darkening and gradual dying off of the lower leaves of violets is a natural aging process. Excess phosphorus in the soil leads to premature aging of the violet.
Spots in the form of a white or light gray powdery bloom. If the plaque is scraped off, the leaf tissue is damaged under it, the leaf gradually turns brown, dries, deforms and dies, the buds covered with a mycelium film do not open. The violet is affected by powdery mildew - these are fungi of several species and genera.
The disease was preceded by a violation of the requirements of the culture: high humidity, too low or high temperature, insufficient illumination, increased nitrogen content in the feeding, with a lack of phosphorus and potassium. Fungus spores often enter the planting substrate with soil taken from the garden.
Предпочтительнее использовать лесную землю или некоторые купленные торфяные субстраты. С токами воздуха споры гриба могут передаваться от растения к растению. Необходимо удалить все пораженные части больной фиалки, а затем с осторожностью подвергнуть обработке инсектицидом (Топаз, Медный купорос, Скор и др.) при помощи распылителя. Если поражение минимально, то лучше не применять столь радикальные меры, а после удаления пораженных листьев, обработать фиалку раствором марганцовки (0,25 г на 1 л воды, светло-розовый цвет), через 5-7 дней повторить. Можно применить раствор антибиотиков: пенициллин 100 ед/мл и стрептомицин 250 ед/мл в соотношении 1:1.
Dark spots covered with a gray fluffy bloom (fungal mycelium) appear more often on necrotic areas of the leaf or petiole caused by burns, insect damage, bacterial diseases, etc. - this is gray rot. In addition to several varieties of gray rot, violets are also affected by other types of fungal diseases, as a result of which rusty, brown, gray spots appear. A distinctive feature of such spots may be the presence of some kind of plaque on them, a darker narrow or wide border around the spot, as well as the presence of spore-bearing pustules of different colors: gray, black, orange spots or bulges.
It is difficult, sometimes impossible, to correctly identify the type of fungal spot. It is known that in nature there are more than 100 thousand species of fungi that parasitize plants. A huge number of them can also infect violets (about 80% of all dangerous diseases are caused precisely by fungi).
The spread of fungi occurs by spores, mycelium particles (mycelium), sclerotia upon contact of a violet with an infected plant, as well as with the help of water, wind, insects, dirty tools, pots, and hands. Fungal diseases are easier to prevent than to cure. The affected parts of the plant are cut and destroyed (hands and a knife are thoroughly washed). The plant is created with comfortable conditions. Watered in the morning, dosed, preventing drying out, but not pouring, so that by night, with a decrease in fluid consumption, the earthen lump is already a little dry. A good supply of fresh air is needed, but by no means a draft. There should also be enough light, in the fall additional illumination will be required (daylight hours 10-12 hours).
Thus, the disease can be prevented. British flower growers do not recommend using any chemicals at home, believing that it is cheaper to lose a flower than to spend money on your own treatment. Like this! In addition, all drugs are powerless against some types of mushrooms. But it so happens that we are afraid of losing the variety that we have been looking for for so long. Then, observing all the precautions that were written earlier in the article The violet dies, we use fungicides (Fundazol, Skor, Chistotsvet, Vetra, etc.) With Kuproksat (copper sulfate), you can disinfect all wounds after removing the affected areas of the plant, as well as it is used for dressing soil that may contain fungal spores.
For prevention, you can add Zaslon or Barrier preparations to the soil, which nourish the substrate and at the same time contain antifungal compounds. If the disease progresses, then it is necessary to choose the healthiest leaf, shorten the petiole and root it. Better in water. If the leaf has not been infected, then spots on it will not appear as the roots grow.
Bacterial spots differ from those of fungal origin by the absence of spore-bearing pustules, as well as the presence of a lighter, pale green border. Bacterial spot can look like small oily spots on the leaves that quickly grow in conditions of high humidity and high temperature, while the petioles and peduncles turn black. The leaves then die off.
During the summer heat, you just want to better water your violets, but overflow at this time is especially dangerous and can lead to the rapid death of the plant. Leaves can be caused by bacterial burns. The edge of the leaf turns black, dries up, and the entire leaf can gradually die off. Young leaves, flowers, peduncles are often affected. Sometimes bacterial infection is accompanied by darkening of the veins on the leaves, bacteria penetrate the vascular system, cause a delay in the flow of water, and cause toxic poisoning of the entire plant.
The causes of the disease are the same as for the defeat of fungal diseases - violation of the conditions of detention. Control measures are similar. Some varieties of violets are more susceptible to bacterial diseases (they must be treated with particular care or disposed of), and some, on the contrary, are very resistant. Preparations for processing: Cuproxat (copper sulfate), Copper oxychloride (copper oxychloride).
How to treat violets
Which fungicils for violets are better
When choosing means of combating diseases of violets, one must adhere to the following rules:
- The fungicide must be approved for home use. Toxicity class 3, not less.
- When buying a drug, you must carefully read the instructions on the package, which should indicate which diseases it can be used for. Some phyto-drugs are only a means of prevention, not treatment. For example, Fitosporin-M and others, if the violet is already affected, then there will be no benefit from them.
- The harm from using the drug should not exceed the benefits. For some diseases, no fungicides are effective, spraying and getting on the roots will only worsen the situation. Initially, you just need to try to remove all the affected parts of the plants, lubricate the sections with copper preparations or sprinkle with crushed coal.
- There are good drugs - biostimulants that increase the resistance of plants to diseases. These are Epin, Zircon, Agate, Potassium humate, Sodium humate. You can spray the plant with one of them after all its diseased parts have been removed and the sections have been processed. It is better to prevent the disease than to fight it, so you can use such drugs in stressful situations for violets. After processing, place in a warm, draft-free and dimly lit place. the drug disintegrates in the light.
- The preparation should not spoil the appearance of the violet after spraying. For example, spraying with Bordeaux mixture leaves a whitish bloom on the violet. When processed by Maxim - red.
- The systemic fungicide is more effective, since it is transferred through the vascular system of the plant to all its parts. Contact fungicides work only on those areas of the plant surface, where they are directly exposed during treatment, in order to improve the contact of the drug with the leaves, it is used together with green soap, and is not sprayed, but the plants are washed. This is a very big work if there are a lot of violets, and for some varieties with wavy leaves, for peduncles with buds, it is impossible.
- It is advisable to avoid the use of fungicides with a strong, pungent odor.
- The best treatment is not chemicals, but culture-appropriate living conditions. Otherwise, no fungicides will help.
The author of the article is T.A. Rusinova
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