Most often, home plants suffer from fungal diseases and the activity of insect pests. First of all, the leaves and root system are affected. By the characteristic signs of lesions, it is possible to determine the cause of diseases of indoor plants and eliminate it in a timely manner.
High temperature and high humidity are an excellent environment for the development of bacteria. For this reason, flowers should be sprayed and watered in moderation, since excess moisture increases the likelihood of the spread of pathogens.
Alternariosis is a fungal disease in which the leaves, tubers and stems of the plant are covered with brown spots. The causative agents are fungi of the genus Alternaria. First, the disease affects the lower leaves, and then the lesion rises higher in concentric circles. Over time, the spots turn black and grow. Alternariosis especially progresses with sudden changes in temperature.
The best environment for the development of microorganisms is a warm and moist microclimate, when the humidity in the room is 90% and the temperature is + 30 ° C.
Prevention of such a disease is good ventilation. Ventilation helps fight mold. Also, one should not allow a high density of shoots to exclude the source of bacteria: excess branches with leaves should be removed in a timely manner.
The disease is caused by deuteromycetes of the genera Gloeosporium, Colletotrichum, Kabatiella. The spots on the affected leaves can have a different shade: sometimes they are gray-yellow, in other cases brown or purple. Spreading, spots acquire a brown tint. They form spores, which appear in the form of hairs. In these places, the surface of the sheet is rough.
The fungus is resistant to frost and spreads with watering. It develops at high humidity and elevated temperatures.
At the initial stages of the disease, affected leaves are removed, watering the plant is reduced in order to reduce moisture. Plants are sprayed with Bordeaux mixture, vitriol, fungicidal preparation Strobi.
Phytopathology is accompanied by the appearance of small brown spots on the leaves with a diameter of 1-2 mm. Growing, they darken, a yellow border forms along the edge of the spot. When the disease affects the stem, then its fracture occurs at the site of infection. The first signs of the disease appear in the form of drying the ends of the leaves. At the border with the healthy part, a darkened, brown stripe appears.
The fungus is a pathogen that is very stable, and can withstand frost and drought. Tolerated with drops of water when sprayed. Control measures are the same as with anthracnose.
The disease is provoked by the activity of mushrooms - oomycetes. At the initial stage of the disease, yellow spots of irregular configuration appear on the upper part of the leaf plate. After a while they turn brown and then turn brown. A gray coating appears on the lower half of the sheet, which then turns black. Ill leaves gather in corrugations, turn yellow and fall off. In the later stages, the disease affects the vascular system of the plant. At the cut, this manifests itself in the form of darkened vessels.
Ideal conditions for the development of phytopathology are:
- high acidity of the soil substrate,
- high humidity,
- limited access to fresh air, poor ventilation of the room.
The source of the disease is poor disinfection of seeds and soil. For prevention purposes, seeds are planted in water at + 50 ° C for 20 minutes before planting. Warm seeds are lowered for 3 minutes in cold water, and then dried in air.
Low humidity is maintained in the room. Bushes require continuous thinning to improve air access. In order to disinfect the soil periodically need to be changed.
When the disease spreads to the plant, the infected leaves and side branches are removed. Spraying is carried out with Bordeaux liquid, Bravo or Quadrice preparations. If the soil is already contaminated, then spraying is excluded.
The disease is caused by ectoparasitic erysiphoid fungi. The first signs of damage are white spots on the leaves with a gray tint in the form of powdery coating. Then these spots darken and turn black. Over time, blackness spreads over the entire sheet, and covers it from two sides. Flowers, along with leaves, dry and fall. Humidity up to 60% and warm air from 15 to 26 ° C are especially conducive to the development of the disease.
To avoid powdery mildew, domestic plants should not be fertilized with nitrogen fertilizers, especially when the budding process is ongoing. Since spores easily cover significant distances, bacteria can be brought in from trees located outside the window. The development of the disease is affected by a lack of air, however drafts are also contraindicated. The affected buds can be treated with sulfur, whey or milk.
With this disease, rusty spots appear on the leaves. If they are rubbed in the hand, then a powder is formed. This disease also applies to fungal. It appears as a result of abundant watering, lack of sufficient lighting and lack of fresh air.
Sometimes the disease enters the earth with the seeds. It is impossible to recognize it in advance, therefore, before planting, the soil and seed are processed with potassium permanganate. Spores of the fungus can be carried by the wind if a flower pot is standing on the window. Therefore, in the spring, all plants should be treated with a Bordeaux mixture for prevention. If rust has affected a small part of the leaves, they should be removed.
The appearance of rust spots can be caused by improper dosage of fertilizers. If the soil substrate has not changed for a long time, the soil should be completely replaced.
Fungal disease caused by the activity of conidia and sclerotia in dead areas of plants. First, the stem is affected, which is covered with a grayish-olive coating. Later, the disease spreads to leaves and flowers.
The stain resembles dry rot or loose cotton wool. It is constantly increasing in size. If the stem is ringed, then its upper part disappears, because tissue decomposition occurs inside, the vessels die and the movement of juices stops.
The causes of the disease may be an infection brought from an open window, high humidity or lack of fresh air. Group plantings should be thinned out constantly, as they can be a source of bacteria formation.
Indoor plants are less likely to be infested by parasites, but sometimes this happens. These pests can be:
- Aphid. An insect that sucks juice from plant tissues.
- Cyclamen tick. It sticks to the surface of the leaves, a large accumulation of ticks looks like dust.
- Nematode. It is difficult to deal with these pests, but they rarely affect indoor flowers.
- Mealybug. This is a small beetle covered in feathers.
- Shield. It is protected by a shield of wax, so the drugs do not act on the insect.
- Grape elephant. Beetle eating leaf.
- Caterpillars. Rarely affect indoor plants.
The maintenance of indoor plants requires constant care and maintenance of the necessary climatic conditions. You need to monitor the main factors: humidity and air temperature in the room. A sharp drop or increase in these indicators cannot be allowed. It is necessary to change the soil more often and check its acidity. So you can avoid damage to indoor plants by fungal diseases and pests.
It describes the most common plant diseases that occur on indoor flowers. Attention: on any plants, in violation of agricultural technology (bay, hypothermia, overfeeding with fertilizers) or when planting in non-sanitized soil, signs of several diseases may appear. In the world around us, not one or two types of microorganisms, but millions. We can guess the disease by single characteristic spots. There are specific diseases that can not be confused with anything: gray rot (long strands of gray mold), powdery mildew (leaves seem to be covered with white dust), dropsy of the succulent leaves (green pimples, the plant is not oppressed), ring patterns from viruses and some others.
But very often in plants several diseases appear simultaneously, for example, in orchids, tracheomycosis (fusarium) and at the same time septoria or phylosticosis. Root rot and alternariosis. The good news is that the fungicides that we are offered in the store are usually effective against many diseases. But do not forget that for personal households (i.e. for home), drugs of hazard classes 3 and 4 are allowed.
Alternariosis and dry spotting
The causative agent is fungi of the genus Alternaria. The fungus mainly affects leaves, sometimes stems and tubers.
Symptoms: first, dry brown spots appear, primarily on the lower, and then on the upper leaves. Concentric circles are usually visible on spots. As the spot increases, it gradually blackens, and gray conidia become visible on it.
Frequent temperature changes and humidity changes, i.e. alternation of dry and wet periods. But the optimal conditions for the development of the fungus at temperatures above about 25-30 ° C and humidity up to 90%.
Avoid thickened plants, while cutting excess branches and leaves. Ventilate the room or the greenhouse, if the flowers are on the balcony, make sure that there is good ventilation and mold does not grow on the walls - this is an indicator of microclimate violations.
Fungicides used to combat alternariosis:
- Abiga peak 50 g per 10 l of water
- acrobat MC 20 g per 5 l of water
- oxychom 20 g per 10 l of water
- home 40 g per 10 l of water
- Alirin-B 2 tablets per 1 liter of water
- Vitaros 2 ml per 1 liter of water
Spraying thrice in 10 days.
The causative agent is fungi of the genera Colletotrichum, Gloeosporium, Kabatiella. More often prone to palms, ficuses, anthurium, etc.
Symptoms: the disease affects the leaves, stems, petioles and fruits of plants. Spots on different plants, and depending on the pathogen, look different.
- Kabatiella zeae - causes the formation of small round or irregular spots, 2-5 mm in diameter with a clear contour. It looks like a yellow spot, with a brown or black dot inside. If the spot is larger, a dark rim is formed instead of a black dot, and a grayish ring is inside.
- Colletotrichum orbiculare - causes the formation of usually reddish-brown, often with a light yellow border of spots, from 2 to 12 mm. On some plants, the spots are pale green. The shape is rounded or elongated. In the affected areas, the spots merge, dry out, become like parchment, crack, holes form.
- Colletotrichum trichellum - large yellowish-brown or gray-brown spots on leaves and stems with dark sporulation pads. If you look closely, it is noticeable that on the spots on the upper side of the leaf, the surface is not smooth, but covered with fluffy hairs of spores, however, the spores are already noticeable when the plant is severely damaged. On fruits, spots are gray-brown with a dark middle, depressed.
Anthracnose develops rapidly in greenhouse conditions, i.e. at high humidity (about 90-100%) and elevated temperature of 22-27 °. And also with frequent (several times a day) spraying of plants. The fungus is frost-resistant - stored in plant debris, in seeds and spreads with water during irrigation.
Why do spots appear?
There are so many different types of orchids. This chic flower is taken by many people who want to decorate their home, but the orchid is capricious in care. Without proper treatment, this flower may soon lose its attractive appearance, become ill and even die. Many gardeners who are fond of orchids at least once encountered the problem of the appearance of characteristic spots on their foliage. They can have a different color, be dry, wet, sticky and even fluffy. Let us consider in more detail what causes the formation of such defects on the leaves.
Often black spots appear on the leaves, which indicates that the plant suffers from a certain disease.
Most often, black spots indicate developing late blight. This ailment often affects orchids and is dangerous.
Initially, the spots on the flower have a purple hue, and then darken, becoming black. If you notice such neoplasms, then you should hurry up with treatment, because the flower can die. In most cases, black spots appear due to excessive watering of the plant.
Black flaws appear on the leaves and in the case of its disease with chlorosis. With such an ailment, the foliage is first covered with dark spots, and then curls.
Fungal infection can also cause black and yellow dots. The size of the spots may vary. It is at this time that the fungus develops actively inside the tissues of the flower. As a result, he can hit the leaflet, because of which he will die.
Sometimes noticeable spots of yellow may appear on the leaves of this beautiful flower. Sometimes their formation indicates uncomfortable conditions of plant maintenance, for example, in direct sunlight. Because of this, very often small yellowish dots appear on the leaves of the orchid. To solve this problem, you do not have to use special medicinal formulations - you only need to rearrange the pot with the plant in a place more convenient for it.
Yellow spots may appear on the foliage of the orchid along with black dots. This will indicate that the plant has been attacked by a fungal infection described above.
And also many flower growers are faced with the fact that uneven convex spots of yellow color appear on the leaves of the flower. Subsequently, they seem to push through themselves an infected area of the leaf. The death of tissue of flower leaves is not the worst problem that can be solved very quickly and simply. The main thing is to provide the orchid with proper and constant care, use suitable water for irrigation.
Yellow spots also appear due to the development of bacterial diseases. With this ailment, the points have a uniform color. Their size usually reaches about 7 mm. Such a disease appears due to too high temperature conditions and poor ventilation in the room.
Brown and brown
Brown and brown spots appearing on the leaves of the orchid may indicate more serious problems. Such defects are both fatty and wet, and dry. So, dry spots are often manifested due to too high levels of humidity in the room where the flower is located. This ailment should be feared, because spots will spread further over the plant over time, capturing more and more areas.
Brown spots on the leaves are also formed due to bacterial rot.
With such problems, defects propagate over the entire surface of the plant. It happens that the orchid leaf is completely blocked by such formations. In this case, there is nothing left but to remove the damaged item.
Brown spots appear on the leaves of the orchid, if there is a disease such as brown rot. The roots of the flower usually suffer from this disease, and then the leaves. At first, small spots fall on the spots, but then defects cover the entire sheet completely.
One of the most common ailments encountered by orchid holders is white spots that appear on the leaves of the plant. If the leaves of the plant are covered with similar lesions, then this indicates an active bacterial, viral or fungal disease.
There are cases when an almost transparent light or whitish coating appears on the leaves. Such a defect usually makes itself felt on the lower leaves of the flower. In the future, spots pass from the leaves to the rhizomes and stem, due to which the latter dry out, and the plant itself simply dies. This serious disease is called powdery mildew. You need to start fighting it as soon as possible. The treatment of such ailments is a complicated and long matter.
The spots appearing on the leaves of orchids are usually not very bright. The most striking and noticeable are usually yellow and white blotches that arise for various reasons. However, it also happens that bright red patches appear on the leaf blades of this magnificent flower. The cause of these defects can be:
- the presence of orchids in direct sunlight, which affect this plant is detrimental,
- brown rot
- spider mite attack, scale insects.
What to treat?
It doesn’t matter at which particular area of the leaf spots and dots of different colors appeared - they can form on top or on the back of the plate.
In all cases, it is necessary to start treatment of the flower in time, otherwise it will die. For this, various chemical agents and effective alternative methods are used.
Today in specialized garden stores you can find many effective and inexpensive chemicals that protect the orchid from all sorts of misfortunes. You can get rid of the spots on the leaves of this flower by using the following popular products, proven by many gardeners:
- special fungicidal solutions
- антибактериальные и антисептические препараты,
- медьсодержащие препараты,
- Бордосскую смесь,
- средство с маслами в основе – Promanal,
- кишечные яды – «Актеллик», «Актара», «Нурелл-Д»,
- контактный яд – «Фозалон» и многие другие.
Прежде чем пускать в ход высокоэффективные химические средства для лечения орхидей, очень важно ознакомиться с инструкцией по их применению. Even if you consider yourself an experienced florist, you should not neglect this rule if you do not want to seriously harm plants and your own health.
If you are a beginner florist, then it is advisable to consult about the use of such funds with specialists who have sufficient experience. This way you can avoid serious mistakes in the treatment of orchids.
Buying all the funds listed (and the like) is necessary only in specialized stores, so as not to stumble on low-quality goods or fakes.
Not all flower growers resort to the treatment of orchids with aggressive chemicals. Of course, they demonstrate themselves as very effective, but you need to work with them carefully if you do not want to harm the flower. Many people decide to abandon the use of such funds, preferring folk methods.
- In many cases, it is enough to isolate the affected plant and provide it with ideal conditions, for example, to achieve the optimal percentage of humidity in the room.
- It is permissible to treat the leaves with cinnamon or activated carbon. Such remedies are effective when it comes to the appearance of dark spots on the leaves.
- Many flower growers treat damaged areas on leaflets with iodine. Of course, such a method will be effective if defects are not already running. If the situation is not simple, then without the use of chemicals, most likely, it will not be possible to do.
Each grower has his own secrets to combat orchid diseases in the arsenal, but experts advise you to immediately contact the chemicals and not lose precious time.
Consider the basic rules for processing orchids, if spots appear on it.
- First, the damaged flower must be isolated from the rest of the plants.
- Fix the size of the spots formed on the plant.
- Do not rush to spray the orchid. Analyze the watering mode you are accessing. If necessary, reduce watering.
- If the speck is dry and does not grow further, then nothing needs to be done - watch how it will “behave” further.
- If the stain is wet and growing, then it is necessary to cut it to a section of healthy green tissue. Dry the cut places and treat with a suitable product. Cinnamon, activated angle or chlorhexidine can be used.
- Treat the flower with phytosporin.
- Handle all tools well. Burn on an open fire.
- Place the flower in a bright place, but not under direct ultraviolet rays.
- Observe the quarantine of the plant for a few more weeks.
Dropsy of leaves (edema)
A disease caused not by a fungus or bacteria, but caused by waterlogging of the soil, often with a lack of lighting. It usually manifests itself in succulents, typically for peperomia, chubby women, Kalanchoe, possibly in pelargonium, Scheffler.
Symptoms: in a plant, most often on the underside of the leaf there are barely noticeable pimples, they seem watery, but actually dense, sometimes like cork growths, some are similar to warts, the color of the leaf may remain, i.e. spots are green, can acquire a gray necrotic color. This is caused by the fact that part of the roots die off (from overdrying, overmoistening, supercooling), and nutrition is disturbed along conducting vessels that were supplied with these very roots. Since waterlogging is not strong, the soil had time to dry out, rotting did not spread further, but the spots remained. Affected leaves will not recover, but if the plant is created good conditions, then the new leaves will be healthy.
The difference between dropsy (edema) from other diseases, root rot is that the plant is not inhibited, grows noticeably, and the spots themselves in small areas, affect 1-3 leaves on the bush. Leaves with dropsy do not turn yellow, do not dry out and do not fall off!
Treatment and prevention: Adjust watering, do not fill, after heavy watering and when compacting the soil in the pot, pry the ground. Make up the soil with a high proportion of draining, loosening particles - at least 1/5 or 1/4 of the volume of the pot.
Do not forget about the necessary preventive measures.
- Provide the plant with proper watering. The soil will need to be moistened again only after 2-3 days, which it will remain dry.
- Take care of proper air temperature. Daily differences should not exceed 4–5 degrees.
- The plant should be lit 10-12 hours a day. Light must be diffused.
- Fertilize an orchid a couple of times a month.
- Pick up good soils containing tree bark, moss, peat and river sand. Provide a good drainage layer.
Powdery Mildew (Peronosporosis)
The causative agents are fungi of the genera Peronospora, Plasmopara, Pseudoperonospora, Mildew. The disease can affect any indoor plants, but the disease is quite rare.
Symptoms: yellow, then brown spots of irregular shape are formed on the upper side of the leaves, with a downy powdery rose of cucumbers, the spots are angular (the specific structure of the leaf). Gradually, necrosis occurs in these places, and the spots become brown. On the underside of the leaves - at the beginning of the disease, a light gray coating from the conidial sporulation of the pathogen that emerged on the leaf surface through the stomata, then this coating gradually blackens. Sick leaves turn yellow, become wrinkled or corrugated, wither and dry. The pathogen with a severe degree of damage can penetrate into the vascular system, which is noticeable on the cut in the form of darkened vessels (mycelium and spores).
The disease prevails in heavy acidic soils. Humidity and poor ventilation aggravate the spread. The source of infection is uninfected soil and seeds.
A common plant disease caused by fungi of the species Podosphaera fuliginea, Erysiphe cichoracearum and Oidium is powdery mildew on Oidium grapes.
Symptoms: at the beginning of the disease, small powdery spots appear on the flowers and leaves. They are easily erased, but then reappear and increase in size, becoming a saturated gray color. Gradually, the mycelium condenses and becomes almost brown. Powdery coating can be on both sides of the sheet. Leaves gradually dry up, buds and flowers crumble, plant growth stops. The most favorable conditions for the development of the disease are high humidity - about 60-80% and warm air in the range of 15-26 ° C.
Of the domestic plants, powdery mildew most often affects: laurel, Saintpaulia, gloxinia, roses, gerberas, Kalanchoe, etc.
The fight against powdery mildew at home
If powdery mildew has got on indoor flowers, and especially violets (senpolia), potted gerberas, indoor roses are especially susceptible, then you can use the same means as for garden plants, except for very toxic ones (bayleton), but fungicides like topaz should be preferred speed
You can use the preparations Chistotsvet, Skor, Rayok - all of them are produced in small packaging, contain diphenoconazole, dilute 2 ml in 5 l of water. For fruit trees, vegetables and berries, we plant 2 g per 10 liters of water, a maximum of 4 treatments: the first - on a green cone, the rest - after 12-14 days, stop processing 20 days before harvesting.
It is quite safe to spray from powdery mildew at home with a solution of soda ash and copper sulphate: in 1 liter of water, dilute 10 g of soda ash and 2 g of soap (household, tar), separately dissolve 2 g of copper sulphate in a glass of water. Pour the copper solution into the soda solution, add water to a liquid volume of 2 l and spray the plants.
If you heard from someone a recipe for the control of powdery mildew with antibiotics, do not try to repeat, penicillins, tetracyclines and other antibiotics do not affect fungal infections, in extreme cases, they will help against bacteriosis, but no more.
You can use drugs such as Topaz, Vectra, Hom, Oksikhom, Bordeaux liquid (1%). How to get rid of powdery mildew on gooseberries, currants, roses and other garden crops - read more: Powdery mildew.
Spraying with iodine solution helps as prevention and treatment: dilute 1 ml of alcohol pharmacy tincture of iodine in 1 liter of water. You can increase the concentration of roses - dilute 1 ml per 400 ml of water.
The causative agent is fungi of the genus Septoria.
Symptoms: dark brown or dark gray spots with a yellowish border (on the anthurium) or, as on azaleas, small reddish or reddish-yellow spots that gradually increase. Then on the spots appear blackening in the center - the fruiting organs of the fungus, which can even overwinter on the leaves at sub-zero temperatures and the disease will begin to spread in the spring. Some forms of septoria have different manifestations (depending on the type of plant):
- The causative agent of Septoria albopunctata - looks like small 2-5 mm reddish-purple or brown spots with a gray center. With the development of the disease, spots increase, and in the center of some of them you can see small dark brown or black spores of the fungus. Over time, the spots merge, turn brown, and the leaf dries out. Ideal conditions for the development of the disease - high humidity and temperature in the range of 28-31 °.
- The causative agent of Septoria populi - the so-called white spotting, first causes the formation of small whitish or gray spots with a brown rim along the edge, round or oval.
When the spots have already appeared and spread further, spraying should be carried out using chemicals: among them 1% solution of Bordeaux liquid popular in gardening (100 g of copper sulfate + 100 g of lime per 10 l of water should be diluted strictly according to the instructions), a solution of copper oxychloride (hom, oxychom), copper sulfate (100 g per 10 liters of water). As well as:
- colloidal sulfur 50-100 g per 10 liters of water
- gates in the system with other fungicides, 4 g per 10 liters of water
- Abiga peak 40-50 g per 10 l of water
- fungicides: pure color, scor, rake, diskor, keeper - dilute any 4 ml into 5 l of water
- Vitaros 2 ml per 1 liter of water
Repeat spraying after 7-10 days.
The causative agent is the fungi of the genus Botritis Botrytis.
Symptoms: most often, the affected areas appear on the stems in the form of a fluffy greyish-olive coating. With further development, the disease passes to leaves, ovaries of flowers and fruits.
Over time, the lesion takes the form of dry rot with concentric spots. After a few days, the stain grows and rings the stem. The first week on the spot there is no sporulation of the fungus, it in the center fades to a straw color, blurred ring-shaped stripes become visible. Gray rot is similar to gray loose cotton wool or mold. Inside the stem, tissue necrosis develops, while the vessels die, and the movement of water stops. Escape above this zone fades.
The causative agent refers to the so-called wound parasites, the infection spreads mainly with wind, dust, splashes of water, unwashed hands, etc. Also contributes to the spread of the disease poor lighting, high humidity, dense group plantings, and the optimum temperature for the development of the disease 17-25 ° C.
Appears in the form of a dry soot film on aucubs, axles, laurels. Caused by the fungus Capnopodium, which settles on the secretions of aphids, whiteflies, and mealybugs. Plaque in itself is not dangerous for the plant, but it clogs the stomata on the leaves, thereby disrupting the respiration process. The plant slows growth and weakens.
Control measures: timely spraying from pests forming sweet secretions (aphids, scale insects, thrips). After recovering from the diseases, wipe the affected plants with a sponge dipped in soapy water, rinse with warm clean water, treat with phytosporin: take a liquid or paste and dilute in a glass of water to the color of a weak tea. Spray the leaves.
Sometimes a soot fungus settles on the surface of leaves affected by other fungi, carefully examine the nature of the spots, put the plant in quarantine.
The causative agent is rust fungi, for example, of the genus Phragmidium or Puccinia.
Symptoms: expressed in the appearance on the upper surface of the sheet of orange-brown tubercles, sometimes yellow or red round spots. On the reverse side of the leaf, pustules are clearly visible - pads (like warts) of oval or round shape. Gradually, the spots grow into stripes, the leaves turn yellow and fall off.
Phyllosticosis (brown spotting)
The causative agent is fungi of the genus Phyllosticta. Of domestic flowers, hibiscus, roses, orchids, etc. are susceptible to the disease.
Symptoms: on the affected plants, small dark reddish or dark purple dots first appear. They grow and turn into brown spots with a purple, almost black border around the edge. The middle of the spot becomes thinner, dries up and falls out in plants with non-greasy leaves, holes form. When viewed through a magnifying glass, black rounded spores can be seen on brown spots. The disease spreads with the wind, non-sanitized soil, drops of water.
Phillosticosis of orchids manifests itself in small spots about 2 mm in diameter, dark brown, slightly depressed, holes do not form, the disease is often called a “black spot”, since the leaf is mottled with small spots as a rash - the spots do not merge into large ones, remain loose, but the leaf turns yellow, and then the spores of the fungus become noticeable. The disease spreads quite quickly, since orchids are often in an atmosphere of high humidity.
- Vectra fungicide - dilute 2-3 ml of the drug in 10 liters of water
- Abiga peak - 50 g per 5 l of water
- gates - 4 g per 10 l of water
- oxychom 20 g per 10 l of water
- fungicides: pure color, scor, rake, diskor, keeper - any dilute 1 ml per 1 liter of water
- Vitaros 2 ml per 1 liter of water
Spraying when the first signs of the disease appear or prophylactic, then subsequent with an interval of 7-10 days. In some plants, you can safely remove the affected leaves (for example, hibiscus), in orchids do not rush to cut the affected areas to healthy tissue, this can weaken the plants even more. You can trim the sheet only when it is already very yellow. The rest is treated with spraying.
This is a group of diseases caused by a number of pathogenic fungi of the genera: Pythium, Rhizoctonia, Phytophthora, etc. All these diseases appear sooner or later on the crown, tops of plants, but infection begins through the root system. If the pathogen is serious, and the plant is young (cuttings, seedlings, seedlings), then the leaves do not even have time to turn yellow - the roots and lower part of the stem quickly rot.
Orchids, senpolia, cacti and succulents are most susceptible to root rot. The reason is a violation of agricultural technology.
The black leg - the scourge of seedlings, manifests itself in the decay of the lower part of the shoot, cuttings. Rot is the most typical - blackening, softening of tissues. The part of the black leg is very striking when the soil is waterlogged, poor aeration, if the lumps of the earth are so dense that there is an anaerobic environment around the roots. The source of infection is unsterilized earthen mixtures, tools, pots and seedlings after diseased plants.
This is a type of root rot. In this case, the plant first slows down growth, fades somewhat, the leaves lose their color, become pale, only then the roots rot and the plant dies. The first impression with this disease is that the plant does not have enough water, but after irrigation the turgor does not recover, and the leaves fade even more. In plants with dense leaves, the leaves do not fade, but are covered with brown broad spots that begin with the central vein.
This is a whole group of diseases having both fungal and bacterial nature.
The causative agents are fungi of the genera Ascochyta, Colletotrichum, Phyllosticta, Pestalotia, Septoria, Vermicularia, and others. Spotting refers to diseases whose causative agent is difficult to identify, it can be anthracnose, septoria, phylostictosis, ascochitosis, but the nature of the spots is not expressed. In this case, brown spots appear on the leaves of the plant, which with the spread of the disease grow in size, merge and affect the entire leaf. If the plant is strong enough, resistant to disease, or is very well looked after, the spots grow slowly and the leaves also dry out slowly.
The causative agent is the fungus of the genus Stangospore Staganospora. A disease characteristic of hippeastrum and some bulbous.
Symptoms: red narrow spots appear on leaves and peduncles, on which spore-bearing crusts subsequently form, the scales completely turn red on the bulbs. In a sick plant, deformation of the leaf begins
Black Spotting Disease - Description
Black spotting appears with dark brown, almost black spots with a bright center or, conversely, light edges. Rounded or oblong swellings may form on the spots. Signs of the disease usually appear in early summer. With rapid development, the disease covers significant areas of leaf tissue, as a result, the leaves prematurely turn yellow and fall, the branches become bare, the plants weaken and poorly develop, bloom and bear fruit. The infection is spread by wind, water and insects. Black spotting progresses during prolonged rains against the background of low temperatures and deficiency in potassium soil. The cause of the disease can be mechanical damage to the bark or leaves of the plant.
Black spotting - prevention
В первую очередь вам нужно ответственно подойти к выбору места, на котором вы собираетесь выращивать ту или иную культуру. Это значит, что светолюбивые растения не нужно сажать в тени и, наоборот, тенелюбивые культуры нельзя выращивать на ярком солнце: это ослабляет растения и делает их восприимчивыми к инфекциям. Of great importance is also the quality of the soil: you must adapt the soil on the site to the requirements of the cultivated crop. When choosing plant varieties, give preference to resistant to diseases and pests. It is also important that these varieties are adapted to the conditions of your region. Disinfect the seed, especially if it came to you from a little-known source. Plant the plants at the recommended times by the professionals according to the developed schemes, follow the necessary agrotechnical conditions, regularly conduct preventive treatment of plants from diseases and pests, maintain a balance in fertilizing and moistening the soil. After harvesting, do not forget to remove plant debris from the site and clean up the soil.
Black spotted tomato
The causative agent of black bacterial spotting, affecting tomatoes in both open and closed ground, is the gram-negative rod-shaped bacterium Xanthomonas vesicatoria. On the leaves of seedlings and young plants, watery point spots form, increasing in size to 1-2 mm, and the edges of these spots gradually turn yellow. On adult plants, spots are located mainly along the edges of the leaves, as well as on the petioles and stems. Bacterial spotting also appears on tomato fruits in the form of dark convex points with a watery border, increasing to 6-8 mm and turning into sores. The causative agent of the disease can persist on seed and plant debris, which is why it is so important to pickle tomato seeds before sowing seedlings.
The bacterium can penetrate the ground organs of plants through cracks, breaks, and any mechanical damage. It spreads rapidly through the tissues: from the moment of infection to the appearance of the first signs, 3-5 days pass, on the fruits the symptoms of spotting appear later, and the infection spreads to neighboring plants within two weeks. The temperature of the air contributes to the development of the disease above 25 ºC, and at a lower temperature, the disease only slows down its development, but does not pass. Another condition for the rapid development of bacterial spotting is increased to 70-75% humidity and direct moisture on the ground organs of the plant. Under such conditions, black bacterial spotting develops rapidly on tomatoes.
The bacterial pathogen is preserved as long as there is a source of nutrition, but on a purely cleaned soil after harvesting it dies after 4-5 weeks.
I must say that scientists have not yet developed varieties of tomatoes that are resistant to bacteriological spotting, but tomatoes that are not subject to fungal diseases provide worthy resistance to black spotting. In the fight against bacteria, preventive measures, such as seed dressing before sowing, are of paramount importance. This can be done in the following ways:
- hold the seeds for one hour in a fungicide solution,
- treat the seeds for half an hour in a pink solution of potassium permanganate,
- dissolve 12 g of Trisodium phosphate in 100 g of water and lower the seeds into the solution for 1 hour, then very thoroughly rinse them in a sieve or under running water for 20-30 minutes,
- hold the seed for 20 minutes in water at a temperature of 60 ºC.
Such simple methods can be used to destroy the infection located on the surface of the seeds, but it is necessary to deal with the internal seed infection differently: soak the seeds before sowing for 6 hours in a one percent solution of Planriz biofungicide.
Tomato seedlings are also subjected to double treatment by Planriz, Fitosporin-M, Gamair or Bactofit before planting in the ground. It is very effective on tomatoes Fitolavin, which destroys not only the causative agents of bacterial spotting, but also bacterial cancer, vertebral rot and other diseases of nightshade crops.
In the future, growing tomato bushes from time to time are treated prophylactically with copper-containing preparations: a one percent solution of Bordeaux fluid, Oksikhom, Khom and other fungicides of a similar effect.
Black pepper spotting
The same bacteria parasitizes on sweet pepper as on tomatoes: Xanthomonas vesicatoria. Most often, it affects young organs, forming on the stems, leaves, cotyledons, fruits and petioles, watery dotted spots, which blacken over time and acquire an angular or round shape. In size, these black spots, surrounded by a yellowish border, reach 1-2 mm. Spots spread along the veins of the leaves, and light yellow necrosis with dark edges are formed in their center. Black convex dots first appear on the fruits, surrounded by a watery border. They gradually increase to 6-8 mm and turn into rotting sores.
Both preventive and therapeutic measures to combat the causative agent of black bacterial spotting on peppers are exactly the same as on tomatoes.
Black spotting on grapes
Black spotting of grapes, or escoriois, or phomopsis, or the death of shoots, or cracking of the bark, or dry sucking, is caused by the fungus Phomopsis viticola. It appears in June at the nodes of annual shoots with black-brown or black dots of a round or oval shape - swelling of tissues with a focus of necrotic cells in the center. As escoriosis develops, the points become more and more, they begin to merge into spots that open in the middle. The darker edges are covered with cork and look like scabs. Spotting usually affects the first 6-7 internodes of the shoot. The lowest leaves, antennae, clusters and even flowers are infected. Necrosis of the leaves is surrounded by a light dense border, from the tension of the tissues, a curly sheet appears, its breaks occur, holes arise. The leaves turn yellow prematurely. Due to deformation and leaf breaks, photosynthesis is weakened, and in the lower internodes of annual shoots more than half of the buds can die. Berries affected by black spotting, which turn dark purple, have an unpleasant taste, and annual wood turns whitish-gray.
The pathogen spreads with dew, rain, wind, insects and enters the plant through mechanical damage and stomata. Black spotting reduces the winter hardiness of grapes, and if you do not fight it, after 5-6 years the disease will destroy the plant.
Growing grapes, you need to give preference to varieties that are resistant to black spotting. The most famous among them are Cabernet Sauvignon, Liana, Traminer, Tavrida, Spark, Riesling, Bastardo Magarach, Relay. If the disease has already affected your grapes, proceed to treatment immediately, however, because the fungal mycelium is deep in the tissues, attempts to destroy black spotting with fungicides will be ineffective, but treating grapes with DNOC or Nitrafen chemicals can affect fruiting bodies and spores. And if you regularly carry out preventive treatments against fungal diseases, then black spotting will bypass your grapes.
During the growing season, as a prophylaxis, grapes are sprayed with one percent Bordeaux liquid or Euparen, Efal, Mikal preparations, and these treatments should be started even earlier than anthracnose prophylaxis and mildew: the grapes are sprayed the first time when the buds are swollen on it, and after 4-5 leaves will appear on the shoots, a second treatment is carried out. The third time the grapes are sprayed after it has faded, it is advisable to use a drug that is effective not only against black spotting, but also destroys the causative agents of powdery mildew and peronosporosis.
In late autumn, if the grapes are severely affected by black spotting, they should be sprayed with a copper-containing preparation after cutting or leaf fall so abundantly that the bushes are literally washed with a medicinal solution. Sleeves with signs of drying should be removed. From black spotting on grapes, the fungicides Maxim, Kaptan, Mankozeb and Triadimenol have proven themselves well. The following preventative measures should be taken to avoid infection:
- plant only a healthy vine,
- regularly inspect the vineyard, monitor the health of plants,
- immediately after detecting signs of the disease, remove and burn affected areas of the plant,
- to tie up shoots, not allowing them to lie on the ground,
- to feed grapes with a balanced fertilizer, which should include trace elements such as zinc and boron.
Since black fungal spotting is a chronic disease, tune in to a long fight. But even if you destroy all pathogens in your vineyard, the preventive work must be continued.
Black spotting on roses
Black spotting of roses is caused by the fungus Marssonina rosae, which affects the leaves and green shoots of the plant. On the upper side of the leaves of the rose, red-white, and then black, rounded radiant spots form, as if bordered by a fringe. The defeat begins with the lower leaves, but the disease quickly covers the entire bush. Sick leaves become gray-brown, curl, die and fall off, the rose weakens, forms fewer buds or refuses to bloom at all. With a severe defeat, some bushes by the fall may even be left without leaves.
As soon as you see the signs of the disease, remove the leaves affected by the disease from the bush and from under it. How to deal with black spotting on roses? Every 7-12 days, treat the bushes with a solution of fungicide - Abig-Peak, Bordeaux mixture, Previkur, Skor, Topaz, Fundazol, Mankozeb, Thiofanate methyl or Trifloxystrobin, and pour soil around the bush 2-3 times with Fitosporin-M solution. In autumn, before covering the rose for the winter, collect from the bush and from under it all the leaves and burn them, and treat the bare bush with a three percent solution of iron sulfate. In the spring, before the start of the growing season, cut the shoots and branches of the rose to healthy wood, and then treat the bush and soil under it with one of the listed preparations.
Black spotting (Marsonin) can be confused with diseases such as brown spotting, peronosporosis, phylostictosis, cercosporosis, septoria, purple spotting, ascochitosis and sphacelloma. However, if confusion occurs in the diagnosis, do not be discouraged: all these diseases are treated with fungicides.
Black spotting drugs (fungicides)
When choosing drugs against a particular disease, you should have at least a rough idea of their effect and purpose. We offer you a list of fungicides that will help you in the fight not only with black spotting, but also with other fungal diseases.
- Abiga-Peak - a copper-containing contact fungicide with a wide spectrum of action, designed to combat fungal and bacterial diseases,
- Bactofit is a biological drug for the fight against bacterial and fungal diseases,
- Bordeaux mixture - a contact fungicide of a wide spectrum of action to protect vegetable, fruit, berry, melon and other crops from fungal diseases,
- Gamair is a biological bactericide for the suppression of certain fungal and bacterial diseases on plants and soil,
- Captan - contact fungicide with a multi-vector mechanism of action on fungal organisms,
- Maxim - contact action fungicide for pickling planting material,
- Mancozeb - contact fungicide protective action against fungal diseases,
- Nitrafen is a complex fungicide with insecticidal, bactericidal and fungicidal properties,
- Oxychom is a systemic contact fungicide with a wide spectrum of action for combating fungi,
- Planriz - a microbiological preparation of bactericidal and insect-fungicidal action to protect plants from many diseases,
- Previkur is a fungicide with systemic properties, which has protective and growth-promoting properties,
- Skor is a systemic fungicide with a long preventive and pronounced therapeutic effect for the fight against fungal diseases,
- Thiophanate-methyl - contact and systemic pesticide, protective fungicide and insecticide,
- Topaz is a systemic drug to combat many fungal diseases,
- Triadimenol is a systemic fungicide used to treat vegetative plants from many diseases,
- Trifloxystrobin is a powerful fungicide of systemic and contact action, which has a protective and therapeutic effect in the fight against plant diseases,
- Phytolavin is a systemic biological bactericide for the treatment and prevention of many fungal and bacterial diseases,
- Fitosporin-M - biological contact fungicide, microbiological preparation for protecting plants from a complex of fungal and bacterial diseases,
- Fundazole is a disinfectant and fungicide with a wide range of systemic effects against a large number of fungal diseases,
- Hom - a fungicide of systemic local and contact action for combating plant diseases,
- Euparen - protective contact fungicide that destroys condial sporulation,
- Efal is a systemic protective fungicide for vegetable and fruit crops from various diseases.
Folk remedies to combat black spotting
Folk remedies are used not so much for treating plants for black spotting as for preventive treatments.
A proven prophylactic is iodine: 1 ml of iodine is diluted in 400 ml of water and this solution is used to treat plants.
One part of the mullein is poured with 10 parts of water, for several days it is insisted and doused with a rose bush in early spring after removing the shelter. Such procedures are carried out from May to July another 2-3 times.
30-40 g of onion or garlic husks are boiled, insisted for 6-8 hours, filtered and used to process rose bushes and soil around them. The flowering bush should be watered with this composition under the root, since if the broth gets on the flowers, it is possible to stain the petals.
Such folk remedies as herbal infusions (horsetail, nettle or other herbs) or a decoction of citrus fruits proved to be ineffective in the fight against black spotting.