Treatment of gourds from diseases. Melon fly: what it looks like and why it is dangerous. Downy mildew on watermelons

Pests and diseases of melon

When growing melons in the backyard, many gardeners are faced with the problem of plant damage by various infections. Diseases and pests of melon can lead not only to growth inhibition, reduced yields, but also to the death of the crop. The main sources of damage are usually considered to be untreated seed material, weeds growing between rows and affected soil. Pests also cause great harm to crops, which suck out nutrients from plant cells, and also carry all kinds of infections.

Symptoms and treatment of diseases

Melon diseases can affect this crop not only in the beds, but also in closed greenhouses. As a result of exposure to diseases, melons develop poorly, and may die completely, so every gardener must learn to identify the symptoms of various infections and take appropriate measures.

powdery mildew

the main symptoms of the disease in question are the appearance of small white spots on the surface of the culture sheets. These spots look like scattered flour. After a while, the spots cover the entire leaf, it becomes brown and brittle, and soon dries out.

Measures to combat this disease are as follows:

• Compliance with crop rotation.

Destruction of weeds and organic remains of melons after harvesting.
Treatment can be carried out with the help of special substances. One of these is sulfur powder 80% concentration. This substance is scattered over the beds every 10 days at the rate of 4 grams per square meter area. The last treatment should be carried out no later than three weeks before the expected harvest date.

• Fusarium wilt

Important! The disease in question can appear in two stages: during the formation of 2-3 leaves or in the phase of crop formation.

The disastrous consequences of Fusarium wilt are the gradual withering of the leaves, their surface becomes light, and then gray spots appear on it. After about 7-10 days, the affected cultures die.

To prevent this disease, the following preventive actions should be taken:

• Cultivation of plants on bulk high beds.
• Place crops on the site according to the rules of crop rotation.
• Collect and destroy weeds and diseased remains of cultivated plants.
• Pre-sowing treatment of grains in a formalin solution of 40% concentration. The seeds are kept in
• this preparation for 5 minutes.
• Correct watering.
• Autumn tillage

Anthracnose

In addition to the culture in question, watermelon can suffer from anthracnose or copperhead. This disease is widely known in melon growing, it affects the surface of melon leaves, after which pink or brown spots appear on it, which begin to grow rapidly. Holes appear on the leaves and the culture begins to dry out. Melon lashes become thin and brittle, the fruits lose their original shape. Another reason for the deformation of gourds is the melon fly.

The following procedures will help prevent the disease:

• Compliance with crop rotation.
• Cleaning beds from organic remains.
• Moderate watering of plants along with loosening the topsoil;
• Treatment of plantings with a solution of Bordeaux mixture 1% concentration. Such operations are carried out with an interval of two weeks. Over the summer, it is necessary to process crops three or four times. Sulfur powder, which is used to pollinate melons, will help get rid of copperhead.

Peronosporosis

The main symptoms of this disease are damage to the leaves in the initial stages of development. At the initial stage, yellowish spots appear on the leaves, which grow rapidly. In the lower part of the plate, a specific purple coating with a gray tint is formed - this is the place of sporulation of the fungus.

You can treat the plant in the following ways:

• Disinfection of seed material in a thermos with hot water, the temperature of which is within 45 degrees. The grains are kept in the liquid for two hours.
• A good effect is the treatment of seeds in a solution of potassium permanganate 1% concentration for 20 minutes.
• During the growing season, the affected crops are sprayed with Oxyhom or Topaz.

root rot

Such diseases most often occur in weakened plants. The root system and stems of affected plants turn brown, after a while the shoots become thinner. Then there is wilting of the leaves and the rapid death of crops. In adult melons, yellowing and wilting of the leaves occurs, the roots and stems near the soil become brown.

You can fight this disease in the following ways:

• Compliance with the rules of crop rotation.
• Regular removal of weeds.
• Moderate watering, which is combined with the loosening of row spacing.
• Disinfection of seed material in a formalin solution of 40% concentration. Processing of grains occurs for 5 minutes.

How to identify and deal with pests

melon fly

Effective methods of dealing with spider mites are:

• crop rotation;
• destruction of weeds and organic residues after harvesting the predecessor crop.

Gnawing scoops

Farm grown in open field melons affected by bacterial, viral and fungal diseases can simply die. At best, diseases will greatly reduce the yield of this melon crop. Sources of infection are seeds, weeds, plant debris, soil. To prevent crop loss from disease, we treat melons in a timely manner with appropriate preparations, we comply with the requirements of agricultural technology and the rules of crop rotation.

No less harm to planting melons in the country (here, like them) is caused by a variety of pests that feed on the juices of these plants. They also affect fruit quality and yield. Some pests are still carriers of diseases, so their timely destruction is required.

powdery mildew

Small whitish spots that appear on the leaves and stems of the plant during this melon disease can eventually cover the entire leaf blade. Foliage, which acquires a brown color, becomes brittle, curls and dries out.

How to fight, treatment

To the timely destruction of any crop residues and weeds near melons, we add the correct crop rotation. When identifying signs of the disease, the treatment of plantings in the country (with an interval of 10 days) with 80% sulfur powder (400 g / 100 sq. M.) Helps. The interval between treatments is 10 days. We carry out the final processing before harvesting for 20 days.

Fusarium wilt

This fungal disease, which most affects middle and late varieties of melons, leads to a decrease in yield and a strong deterioration in fruit quality. Fruits from affected specimens have low sugar content. They are not flavorful or juicy enough. Affected fruits are poorly stored. The disease on fruits manifests itself after the appearance of 2-3 true leaves on seedlings, as well as during the period of fruit ripening. Leaves and stems of affected adult plants quickly wither. In this case, the leaf blades become light and covered with gray spots. The infected plant dies in 7-10 days.

How to fight, prevention

Compliance with the rules of crop rotation, with the timely removal of plant residues, weeds and the destruction of infected plants. Moderate watering of plantings, autumn deep digging of the soil. Before sowing, the seeds are disinfected in a solution of 40% formalin (5 min). We grow melons on high ridges. During budding, we spray country plantings with a solution of potassium chloride.

Anthracnose (verdigris)

With this disease (another culture familiar to us also suffers from it -), rounded brownish or pinkish spots that appear on melon leaves gradually increase in size. Holes appear on the affected foliage, the leaves twist and dry out. On a diseased plant, the lashes become thin and brittle. Infected fruits are deformed and quickly rot.

How to fight and heal

We remove the remains of crops from the beds in a timely manner, adhere to the rules of crop rotation. We carry out moderate watering, after which we loosen the soil. Spraying plantings of melons with 1% Bordeaux mixture or pollination with sulfur powder. Such treatments (with an interval of 10-12 days) will require 3-4.

Downy mildew (downy mildew)

With this fungal disease, leaves are most often damaged at an early stage of development, with the appearance of yellow-green spots on them, which grow strongly in size. At high humidity, a gray-violet coating (sporulation of the fungus) occurs on the underside of the leaf plate.

Disinfection how to deal

Disinfection before sowing seeds of melons, by heating them in a thermos with water, the temperature of which is 45 degrees. Warming up is carried out for 2 hours. A 20-minute treatment of seeds in a 1% solution of potassium permanganate is shown. We save dacha plantings affected by the disease with a solution of urea (1 g / 1 l of water), 1% Bordeaux mixture (1 l / 10 sq. M.). We treat plants with a 10-day interval with such preparations as Topaz or Oksih.

root rot

Weakened melon plants are most susceptible to this disease. On young specimens, browning of the stem and roots occurs. Over time, they thin out. It all ends with the withering of the cotyledons, leaves and the death of the plant. On adult melons, yellowing and wilting of the leaves are observed. The lower part of the stems and roots acquires a brown color.

Prevention and disinfection

We comply with the requirements of crop rotation, remove weeds in a timely manner, regularly loosen the soil, and carry out moderate watering. Before sowing the seeds, we disinfect them in 40% formalin (5 minutes).

Description of the signs of melon pests, prevention and control

melon aphid

These very fast multiplying sucking pests (which also annoy others), accumulating in groups from the bottom of the leaf, cause considerable damage to the plant. Affected melon leaves turn yellow, curl and dry out. The flowers fall before they open.

Fight her

We clean the beds from plant residues and weeds in a timely manner. We spray summer plantings with 10% karbofos, soapy water (100 g / 10 l of water), 30% Aktelik solution.

spider mite

These small pests settle at the bottom of the leaf blade. Thin cobwebs on the foliage testify to their presence. These insects suck the juice from all parts of the plant. Melons affected by pests gradually turn yellow and die.

How to fight

We destroy all weeds, plant residues and carry out deep digging of the soil in the fall. We comply with crop rotation requirements.

wireworms

Planting melons in the country can be attacked by real (larvae of click beetles) and not real (larvae of dark beetles) wireworms. They gnaw through the underground part of the stem, which often leads to the death of young plants.

Prevention

Timely remove weeds and plant remains in which this pest likes to accumulate.

Gnawing scoops

The caterpillars of these insects live in or on the soil. These pests damage the stem of the melon, sometimes resulting in the death of the entire plant.

Pre-Prophylaxis

We remove plant residues and weeds. In autumn, we dig deep into the soil. We follow the rules of crop rotation.

Having applied all these simple, but effective means of protection, we will enjoy not only fresh fruits (here, by the way, there are many recipes), but we will also cook such a homemade preparation for the winter, which goes so well on winter evenings.

Diseases and pests cause great harm to gourds, many of which are easier to prevent than to deal with them during mass dissemination. Consider what diseases melons and watermelons affect these plants and methods for their treatment and prevention. TO preventive activities include all agrotechnical methods (compliance with crop rotation, deep autumn plowing or digging, destruction of plant residues and weeds, timely sowing, application of mineral fertilizers, etc.) that contribute to good growth and development of plants and increase resistance their diseases and pests.

Fusarium, or wilting

This disease causes significant damage to melons, especially on loamy and clay soils, where the water-air balance and food regime are often disturbed. The disease is caused by fungi of the genus Fusarium, which live on plant debris, in the soil and on seeds. The fungus enters the plant through root hairs, young tissues and damaged areas. The external signs of fusario are varied - the seeds are affected and rot, the roots die off or the root collar or subcotyl knee softens, seedlings and adult plants wither. In the latter, the leaves lose turgor, their color becomes light green, with a yellowish tint.

In the fight against fusarium, the above are of great importance. preventive agrotechnical Events . It is also recommended to pickle the seeds with Prestige before sowing (according to instructions). During the growing season, plants are given regular and foliar top dressing. In the first case, 1 g of superphosphate and 5-6 g of ammonium nitrate are added per 1 sq. m. Foliar top dressing is done with a 5% solution of superphosphate at the rate of 0.3 l of solution per 1 sq. m.

bacteriosis

This melon and watermelon disease is caused by bacteria. It appears in the form reddish brown spots on cotyledons and leaves and elongated brown spots on stems. Bacteriosis is transmitted through seeds, plant debris and soil.
In the fight against bacteriosis, a strict alternation of cultures is necessary, the destruction of the remains of affected plants and the disinfection of seeds with formalin. Seeds are kept in a solution of the drug for 10-15 minutes, and then dried. During the growing season, plants are sprayed with 1% Bordeaux liquid: 0.25 -0.3 l / sq. m. The first spraying is carried out immediately after the discovery of the disease, and then after 15-20 days. Do 2-3 sprays in total.

Anthracnose

This is a fungal melon disease, its causative agent (mushroom) hibernates on plant debris. Distributed by insects and seeds. All plant organs are affected, on which brown streaks appear. pinkish copper shade of stain. Diseased leaves crumble and stems break easily. The fight against anthracnose is carried out in the same ways as with bacteriosis.

In the open field, it is imperative to provide for the installation of temporary film shelters by the time the melon fruits are formed. They are needed in order to prevent the ingress of precipitation, due to which the surface of the fruit cracks, favorable conditions are created for the occurrence of tribute and watermelon diseases, the spread of various rots, while the marketability and quality of the fruit drops sharply.

Downy mildew, also called downy mildew, is less common on melons than true powdery mildew. However, it also causes serious damage to melon crops. This disease is especially widespread in areas characterized by a hot and dry climate. At the same time, downy mildew affects melons both in open ground and in protected ground with equal force, and it can manifest itself at any stage of plant development.

A few words about the disease

At high humidity, the spots located on the lower sides of the leaves are covered with a grayish-purple bloom, consisting of an accumulation of spores of fungal origin. The unfortunate spots begin to spread over the entire surface and eventually lead to the inevitable death of the leaves. The affected leaves turn brown and fall off, and only bare petioles remain on the infected vegetation, which are heavily crumbled at the points of contact with the leaf blades.

Fungal conidia are formed on adult plants, which are carried by the wind over great distances and thereby infect healthy melon plantings. And the duration of the incubation period, if the air temperature does not fall below fifteen degrees and does not rise above thirty, is only three days.

The causative agent of melon downy mildew is the fungus Pseudoperonospora cubensis Berk et Curt.

How to fight

The use of resistant varieties and hybrids will also serve well. There are a number of foreign melon varieties that are relatively resistant to downy mildew. These include Tag (k-6817, India), Takada (k-6787, Japan), Planters Jumbo (k-6440, USA), Perlita (k-6572, USA), Edisto 47 (k-6094, USA), as well as k-5896 and k-5367 from China. If possible, it is desirable to pay attention to them.

In the fight against downy mildew of melon, drugs such as Oksihom (for ten liters of water - 20 g) and Topaz (only one ampoule is taken per ten liters of water) have proven themselves to be excellent. Spraying with these products is carried out with a fine spray in order to properly process the leaves from both the upper sides and the lower ones.

You can also carry out preventive spraying of growing crops with suspensions of "Kaptan" or "Cineba". If the disease is focal in nature, then the treatments should also be focal.

It is not recommended to spray melons during the flowering period, and at the fruiting stage they are treated with one percent Bordeaux liquid with an interval of a week and a half. Approximately five to seven days before the start of the harvest, all processing must be stopped. By the way, more than three such treatments in one growing season are not recommended.

A good effect is also given by folk methods of dealing with downy mildew of melon. Often, melons are sprayed with whey or its solution, for the preparation of which seven liters of water, three liters of whey and a teaspoon of copper sulfate are mixed. And in the fall, all beds with post-harvest residues are first treated with copper sulphate (only 50 g is needed for ten liters of water), and then, after two or three days, all residues are raked out and immediately burned. If such a simple measure is neglected, it will subsequently be extremely difficult to get rid of the infection, since the pathogen easily persists in the soil for up to seven years, and places for strict observance of crop rotation on modern summer cottages usually not very much. Ideally, even after such treatments, it is undesirable to grow melons in the same beds for two to three years.

Focusing on the number and size of the ovary, gardeners sometimes forget to monitor the condition of the plants themselves, missing the moment of infection of watermelons with such diseases dangerous for the culture as true and downy mildew, all kinds of rot, as well as other diseases. Fusarium and anthracnose cause the greatest damage to the crop.

Therefore, when you see a rotten watermelon on melon, you should blame your own carelessness and pathogenic fungi, bacteria and viruses that cause most of the diseases of this plant.

Penetrating through the root system and even the slightest tissue damage, the harmful Fusarium fungus settles and spreads throughout the plant through the vessels. A watermelon infected with this disease suffers and wilts because:

• his vascular system is clogged;
• the amount of toxins secreted by the fungus accumulates.

It is not surprising that the spread of watermelon disease, as in the photo, begins with the roots and lower part of the lashes, because the fungus in the soil and on plant debris remaining on its surface can live for more than 4–5 years.

As a measure of control and prevention, after harvesting, it is imperative to collect and destroy the dried parts of the lashes, disinfect the soil, and it is even better to replace it in the greenhouse. The defeat of watermelons with a disease of this kind contributes to:

• general weakening of plants;
• waterlogging of the soil;
• non-compliance;
• soil cooling down to 16–18 °C.

The first alarming signals about the presence of the disease can be seen already when growing seedlings. Young shoots with a weak root system are quickly affected by a fungal infection present in the soil. If the crops are not processed in time and the infected sprouts are not rejected, the watermelon disease can also get to the melon.

It has been noted that the disease is less common on well-drained light soils, with regular loosening of ridges and receiving potassium-phosphorus supplements by plants, including foliar ones.

Anthracnose - a dangerous disease of watermelons

This disease of watermelons, found everywhere, except for the south of the country, affects all melon crops. Brown or yellowish spots of indefinite shape appear on the green parts of plants. As these spots expand, the leaves dry up and fall off, the stems weaken and break off easily. And the ovary affected by anthracnose is deformed, its development slows down or stops completely. As a result, stunted plants and rotten watermelons can be seen on melons.

Elevated air temperature, lack of ventilation and light, as well as excessive soil moisture are the main factors contributing to the development of this disease of watermelons. When it is possible to establish a regime and provide airing for plantings, anthracnose stops spreading.

The source of the disease - a pathogenic fungus persists not only on dry parts of plants remaining on the ground, but also on seeds. During the growing season, the infection is transmitted during rain and wind, inaccurate watering, and also by insects.

Root rot of watermelons

The culprits for the spread of this group of diseases on watermelons are harmful fungi that first affect the root system, and then the entire plant. The disease can be recognized by the appearance of brown spots on the lower part of the stem and root, with root rot most damaging to seedlings. First, leaves turn yellow and wither on young plants, and then focal death of seedlings is observed.

From the lower leaves and sections of the stem, root rot begins in adult plants. The death of the root system starts from small roots, gradually capturing the main roots that feed the plant.

The development of root rot, as well as other similar diseases of watermelons, is promoted by uneven or excessive watering, disharmonious feeding and low soil and air temperatures. If a beneficial atmosphere for the fungus is created on the melon, pest spores develop and persist on dead tissues.

To reduce the risk of rot development, it is important not only to carry out regular fertilizing, to prevent overflowing of the beds and to loosen the soil under the lashes, but also to remove all weeds and dried plants.

When growing melons early, temperature fluctuations that are beneficial for the fungus should not be allowed. Crops are covered with a film or non-woven material, protecting both from a decrease in temperature and from excessive heat.

This disease of watermelons is considered one of the most common not only on this plant, but also on other melons. The first signs of the disease are already found on the cotyledon leaves. But if here the spots are rounded or shapeless, then on real leaves the spots are limited to veins and already have a pronounced angular shape. The tissue inside the stain first turns brown, and then dries and crumbles.

When the fruit is affected, the brownish spots that appear grow over time, have an oily blurry appearance. The tissues under such spots change their appearance up to the middle of the fruit, as a result, watermelons are deformed and completely lose their quality. Even small manifestations of the disease on watermelons, as in the photo, lead to the worthlessness of the fruit, which rot after a short time.

The infection persists on plant debris, in the upper layers of the soil, as well as on inventory, structural parts of greenhouses and containers for storing watermelons.

If the melon is damp or dew falls, drops of a liquid teeming with bacteria appear in places damaged by rot. As a result, the source of infection with insects, moisture and equipment is spread to neighboring plants and ridges. The penetration of the bacterial flora occurs through the damaged surface of the stems, leaves and ovaries.

In just 5-7 days, the bacteria produce the next generation and are ready to infect new plants. Therefore, it is from bacterial rot that 30 to 50% of plantings and crops can die.

Powdery mildew on gourds

A whitish or gray-pink coating on the leaves of gourds may mean that the plant is infected with powdery mildew. This is the first phase of the watermelon disease. Then heavily inseminated leaves become deformed, weaken and dry up, and at the site of the lesion by autumn you can see black dots - the fruiting bodies of the fungus, ready to capture healthy plants in the spring.

Poured fruits with powdery mildew are rarely affected, but the damage of this watermelon disease is very high. Plants inseminated by the fungus develop poorly, form ovaries worse, and the fruits do not gain juiciness and proper sweetness.

During the summer, harmful microorganisms give several generations, remaining for the winter on the remains of plants.

The optimum temperature of infection is 20-25 ° C, but even outside this range, the causative agent of this disease of watermelons is able to infect plantings, and powdery mildew is observed even in dry times, but in the presence of abundant morning dew.

Downy mildew on watermelons

Downy mildew is found on the leaves in the form of angular or rounded spots, and on the reverse side of the leaf plate there are traces of a gray or lilac plaque, consisting of fungal spores.

The infected parts of the plant become brown, withered and die, and the pathogens of watermelons remaining on them, as in the photo, in a favorable soil environment survive from 2 to 3 years, remaining even after frosts and thaws.

During the growing season, peronosporosis spores are carried with inventory, the disease is especially often observed at high humidity and fairly warm weather.

Favorable soil for the resettlement of mushrooms is the air temperature reduced to 12-15 ° C, excessive humidity, as well as the use of cold water for irrigation. More often weakened plants suffer from white rot. You can reduce the risk of infection and crop loss by observing the rules of agricultural technology and crop rotation, removing all plant residues from under the plants and at the end of the growing season.

Small traces of white rot found on the lashes can be carefully cleaned, treated with crushed coal or chalk.

Gray rot

A distinctive feature of this disease of watermelons is a gray, accompanied by massive sporulation, plaque, which is preceded by a process of decay, when the tissue becomes watery.

In the soil, the fungus that causes the disease of watermelons persists for 2 years. The best conditions for the start of the mass development of gray rot are created when the air temperature drops to 16–18 ° C.

On melons and gourds, the development of two types of mosaic disease is possible, which, according to external signs and the type of pathogen, seriously differ from each other.

The common cucumber mosaic, which affects all pumpkin plants, usually develops on adult plants and is expressed in the appearance of green and yellowish areas on the leaves and tissues. In this case, the surface of the sheet plates is often deformed, acquiring a swollen appearance in places.

However, the disease of watermelons shown in the photo is manifested not only in this. Infected plants develop worse, leaves become smaller, internodes become shorter. The initial phase of the disease affects the tops of the shoots, the mosaic is especially pronounced at the time of fruiting, when the leaves completely die on the lower parts of the lashes, and then the lashes themselves weaken, the flowers fall off, the fruits acquire a mosaic color, deform and do not develop.

This type of mosaic disease of watermelons is more common in warm regions of the country, for example, in the Crimea, the Kuban and the Caucasus region. During the growing season, the mosaic virus can be spread by aphid colonies; in cold weather, the pathogen persists on the seeds of gourds, as well as on the roots of perennial plants, including weeds.

If plants are infected with the green mosaic virus, convex swellings become visible on the leaf plates, but light green patches of mosaic color are not always formed. The disease in most cases settles in greenhouses. The green mosaic can spread when damaged parts of the plant come into contact with healthy ones. This happens when pruning lashes, pinching barren flowers or removing fruits. The disease-causing virus overwinters on seeds and plant debris, as well as in the topsoil.

You can reduce the risk of developing a dangerous watermelon disease by:

• using tested, disinfected seeds for sowing;
• using disinfected soil mixtures for sowing and observing the rules of crop rotation;
• planting only healthy seedlings;
• observing the methods of agricultural technology, including the rules for watering and protecting the plant from low temperatures;
• destroying weeds, especially field thistle;
• timely removing diseased watermelon plants;
• destroying aphid colonies in the area.

System of measures to combat diseases of watermelons

Since the causative agents of diseases of watermelons on particles of plant residues, weeds, inventory, soil and seeds can remain viable for up to several years, the set of measures to combat diseases is necessarily based on prevention.

Plant residues from areas where watermelon diseases are noted must be burned or sent to compost, which takes at least two years to rot. At the same time, such compost is regularly moistened and dug up. The soil cleared of plants in the fall is dug up on a spade bayonet with an earthen clod overturned.

Fruits even with slight damage and rotten watermelons should not be stored and come into contact with healthy ones. The fruits intended for food and for obtaining seeds are regularly inspected, rejecting watermelons with traces of spoilage.

Since pathogens of dangerous diseases, such as downy and powdery mildew, bacteriosis and anthracnose, as well as viral mosaic, remain on watermelon seeds during the winter, it is important to take seeds for sowing only from healthy fruits. To prevent diseases of watermelons of fungal and bacterial origin, the seeds are disinfected.

For sowing watermelons, lighted, easily ventilated areas are chosen, where melons, cucumbers and other representatives of pumpkin crops have not been grown for at least 3-4 years before. We must not forget about such methods of prevention as:

• regular accurate loosening of the soil;
• plant nutrition, providing the bushes not only with basic nutrients, but also with microelements;
• not affecting the leaves morning and evening watering with water heated to 22–25 ° C;
• maintaining a comfortable temperature regime of air and soil.

At the first signs of downy mildew and bacterial blotch, gourds are treated up to three times, after 1–1.5 weeks, with 90% copper oxychloride. From the manifestation of powdery mildew, colloidal sulfur that is non-toxic to humans, animals and bees, which is used for irrigation at the rate of 50 grams per 10 liters of water, will help. Watermelons stop processing a day before harvesting, which must be washed before eating.

In seedling boxes and greenhouses where gourds are grown, it is advisable to regularly change the soil to a depth of 20 cm or disinfect with special mixtures or copper sulfate.

Protecting plants from fungal and bacterial diseases - video