Gladiolus: diseases and pests

Growing gladioli is an exciting and rewarding activity. A wide variety of varieties attracts florists. Beautiful inflorescences of various shapes and colors can transform the site. But some gardeners, instead of luxurious plants, see small inflorescences, twisted trunks on the flower bed. The main reason lies in the fact that inexperienced amateurs pay attention only to flower care. And often overlooked another important step in growing a flower - the prevention and treatment of diseases or pest control.

What diseases are found on gladioli

The main diseases of gladioli that occur on plants are divided into infectious and non-infectious. Often, infection occurs with seed or through the soil. Some pathogens are carried by pests that attack gladioli. As a result of damage, gladioli cease to bloom, severe damage leads to the death of plants. Therefore, the planted flowers are regularly examined in order to take the necessary measures in time, and they carry out preventive measures. It is necessary to know the signs of diseases and the types of pests that reduce the vitality of gladioli.

Gladioli are susceptible to diseases that affect all bulbous crops. But if these diseases are less dangerous for onions, then gladioli tolerate them harder. This is due to the constant work of breeders to improve varieties. Many modern species cannot be grown without the constant use of special means. Most of the pathogenic microorganisms that cause disease are found in the soil. Therefore, it is rather difficult to fight them.

The causative agents of diseases can be divided into groups:

  1. Viruses. Viral diseases spread in any region and cannot be completely cured.
  2. Mushrooms. Fungal infections often affect plantings of gladioli on acidic soils.
  3. Bacteria.

Plants are infected with spores or through the root system. Some diseases of gladioli develop on weeds, which are often the main vectors. In addition, the causes of gladioli diseases can easily be:

  • unfavorable climatic conditions;
  • failure to comply with the requirements of agricultural technology;
  • illiterate choice of variety.

Before you start growing and breeding gladioli, stock up on useful information about possible problems. The article will list the main pests, as well as diseases of gladioli and their treatment, a photo of each problem.

Fungal diseases

Fungal diseases of gladioli are also called rot.

Among them, the most dangerous and most common is considered fusarium or dry rot.

This disease is caused by the fungus Fusarium oxysporum f.Gladioli. Among modern varieties, gladioli that are resistant to this insidious disease have not yet been bred.

The causes of the disease are:

  • a combination of waterlogging of the soil and humid warm weather;
  • excess nitrogen in the diet;
  • planting gladioli on moist heavy soils;
  • strong thickening of plants.
Attention! Corms require the most attention in the period immediately after digging for storage and after planting in the ground.

How to determine the defeat of Fusarium?

Outwardly, the disease manifests itself at first by the curvature and thinning of the leaves, and then by their yellowing and drying out.If you look at the corm, then red-brown depressed spots are visible on it - signs of the disease.

The danger of Fusarium is its widespread distribution. If the corms are weakly affected by the disease, then this will not save neighboring healthy plants from infection. It is especially important to inspect the material before storing it in order to protect the rest of the gladioli. At the first signs of fusarium, diseased corms are removed. If the disease is noticed in the plantings, then they are dug out simultaneously with the soil around the plant. You can prevent the appearance of a fungal infection:

  • disinfection of corms in Fundazol solution;
  • dusting the planting material with the same preparation before planting;
  • alternating 15-minute warming up (55 ° C) and cooling in cold water.

If the infection could not be avoided, then the soil must be treated with thiazone with sand (1: 1). The mixture is applied during the autumn or spring digging of the soil.

The next gladiolus disease known to many gardeners is sclerotinia or black dry rot.

Like the previous fungal infection, it has the same reasons for its rapid development. But on acidic and damp soils, damp cold weather stimulates the spread of the disease. A sign of damage will be the appearance of small dark spots on the leaves. The leaves become weakened at the base, turn yellow, then dry out. On the corm, there are no pronounced signs of the disease, but during storage the disease manifests itself. Spots of a yellowish tint appear, which, with increasing, change color to red-brown, then black. The corm itself becomes hard and rots.

Gladioli of early varieties are more resistant to black dry rot disease. Preventive measures and methods of combating the disease are identical to those described above. If the soil on the site is heavy, then it will help:

  • the introduction of coarse sand for planting gladioli;
  • reduction of soil acidity and moisture by known methods;
  • harvesting corms before the onset of bad weather.
Important! To prevent disease, do not apply fresh manure under the gladioli.

Another serious disease that requires the attention of flower growers is gray rot or botrytis.

Caused by the fungus Botrytis gladiolorum. It can develop at any period of the life of gladioli and affects all organs of the flower.

The leaves are covered with small brown spots with a red border. They grow, changing the color of the leaves, which die off. In wet weather, a fluffy bloom is visible on the leaves. The stem breaks, then lays down, and the rot penetrates below. The corm dies. The spores of the fungus are carried by water and wind. Control measures do not differ from other fungal diseases, but you can add treatment with a solution of baking soda of corms before planting (50 g of powder per bucket of water).

Less common diseases are penicillous and hard rot, smut, curvularia.

Bacterial diseases

They pose a great danger to gladioli when grown on alkaline and neutral soils.

The most common disease is recognized scab.

The tops of the leaves turn yellow, and at the bottom of the plant, spots of a red-brown hue are formed. Subsequently, they are transformed into stripes along the leaves. The leaves rot, the stem breaks at the base. On the corm, spots are also formed. First yellow, then brown. During the storage period, the spread of the disease is not observed. Before planting, the scab is cleaned off and the cut site is treated with brilliant green. Scab control products are ineffective. The best technique would be to sample healthy material and carefully follow the requirements of agricultural technology.

Cancer.

The main carriers of the disease are nematodes and soil bacteria. A build-up forms at the bottom, premature germination of children may occur. In case of illness, the peduncles become less durable, the flowers are small, the decorativeness of gladioli decreases.To cope with the disease, it is necessary to thoroughly sterilize the soil, destroy diseased gladioli and carry out the pre-planting treatment of corms with "Fundazol". The disease does not occur very often, but it is dangerous for nearby growing cultivated plants.

Viral diseases of garden gladioli

Flowers can be affected by diseases:

  • yellow bean mosaic;
  • cucumber mosaic;
  • jaundice of asters;
  • annular spotted tobacco;
  • annular spotted tomatoes.

The list speaks for itself, because these diseases are found on other plants.

A common problem is yellow mosaic virus.

An alternation of colored and unpainted areas appears on the flowers, which gives the inflorescences variegation. The flowers themselves become small, and the inflorescences become elongated. Corms acquire tuberosity or, conversely, become flat, have a bluish tint. Transmission of the disease virus is possible at the time of cutting, by corms or their children.

Cucumber mosaic also leads to streaking throughout the plant.

From this disease, gladioli quickly fade, look depressed with deformed peduncles.

When affected by mosaics, the spots can take the form of a closed ring, the leaves begin to curl. The bulbs become smaller. The carriers of these diseases are pests of gladioli (aphids, thrips). To overcome the mosaic, it is necessary to fight against parasites. Additionally, strict adherence to agrotechnical requirements is required, the removal of all diseased plants, the choice of healthy planting material. It will not be possible to achieve a complete victory over the disease with the help of chemical agents, therefore, disease prevention will be the main weapon in the fight against mosaics.

Jaundice of asters

May lead to the appearance of flowers of a green tint, thin seedlings resembling cereals, curling of inflorescences.

List of the main pests of garden gladioli

Thrips - pests of not only gladioli, but also other plants.

Therefore, the fight against them must be carried out throughout the entire area. This insect feeds on sap, which greatly weakens the plants, reduces their decorative effect.

The danger of thrips is increased by its ability to carry viral diseases. Severely affected flowers do not open, the larvae of the parasite are inside the bud.

Important! After digging the corms, be sure to treat them with insecticides! During storage, thrips live there.

You need to fight the pest by spraying the plantings with insecticides and treating the bulbs. At least three sprays are carried out per season.

Wireworms.

So, they call the larva of click beetles. This pest eats up the bulb from the inside.

If this defeat does not lead to the death of the gladiolus, then the danger of fungal diseases remains due to the resulting wounds on the tubers. This pest feels good on carrot and potato ridges, in places with a high distribution of wheatgrass. Therefore, it is not worth planting gladioli after these crops.

Advice! Gladiolus will feel good after tomatoes, garlic and legumes.

Onion root mite.

In addition to gladioli, lilies, tulips, hyacinths suffer from this pest. They penetrate the bottom of the bulb and lay eggs. The larvae feed on the juice of gladiolus corms, weaken the plant. To prevent defeat, you need:

  1. Observe the crop rotation. Do not plant gladioli after other bulbs.
  2. Clean material from old scales before storing.
  3. Carefully remove plant residues from the site.
  4. It is imperative to carry out heat treatment and disinfection of tubers.
  5. Spray with onion mite preparations.

General preventive measures to protect gladioli from diseases and pests

The main focus on the site has to be paid to disease prevention. After all, a diseased plant, at times, cannot be cured. And even beginner growers can prevent this problem.Therefore, simple recommendations for the prevention of diseases will be useful to everyone.

When growing gladioli, you must:

  1. Mandatory observance of crop rotation. Flowers tolerate one place well for no more than two years in a row. Then they begin to hurt more, and a year later, a massive flower disease may begin. This is due to the multiplication of pathogenic microorganisms that cause diseases - rot and fusarium. Good helpers in soil disinfection are nasturtium, marigolds, calendula and mustard. These plants are planted in the places where gladioli grew. Many growers place their plantings around gladioli, which brings the same effect and helps to avoid disease.
  2. Planting plants in ventilated areas. This helps to contain the rapid spread of fungal infections.
  3. Do not leave diseased plants next to healthy ones. It is necessary to remove along with the corms and part of the adjacent earthen coma.
  4. Conduct preventive spraying of healthy gladioli. For these purposes, an infusion of garlic is used (it is prepared from 100 g of ground garlic and 10 liters of water) and a solution of potassium permanganate (5 g of the product is enough for a bucket of water). Potassium permanganate, simultaneously with soil disinfection, enriches it with potassium. This processing is carried out at the beginning of September. Chemical compositions are used only in the initial stage of gladioli disease. They are not intended to cure, but only to protect nearby healthy flowers growing.
  5. Mulch the planting of gladioli with pine needles to prevent the appearance of diseases. Sphagnum moss is also good for preventive purposes.
  6. Periodically spray gladioli against pests and diseases with preventive solutions of copper oxychloride and copper sulfate. Enough 20 g of substance in a bucket of water.
  7. After harvesting corms for storage remove all plant debris on the site to reduce the possibility of wintering pathogens and pests.

These simple activities will allow you to preserve your favorite varieties for several years and protect them from diseases and pests.

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