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Gladiolus - one of the most spectacular garden flowers, and doubly offensive when plants wither, buds never open, and the corms rot. To prevent this, you need to know the diseases of gladioli and their treatment, and photos and descriptions of the most common problems will help in time to cope with them.
Most often, flower growers face diseases caused by bacteria, harmful fungi and viruses. A lot of troubles can also be done by pests that are dangerous for bulbous cultures.
The fungal diseases of gladioli and their treatment
The fungi causing diseases are easily preserved in the soil, their spores are transported by wind and drops of water, and the harm from contamination of the gladiolus is noticeable on all parts of the plant.
One of the most dangerous and incredibly common problems is fusarium or dry rot. As can be seen in the photo, without treatment, the gladiolus disease leads to the appearance of brownish-red concave putrefactive spots on the bulbs. If such a plant is planted, even with a small degree of infection, the emerging leaves turn yellow and wither. And this is a sure sign of decay and withering away of the root system.
Depending on the stage and time of fusarium infection, the gladiolus dies before flowering or still forms an inflorescence. But when the bulb infested with fusariosis falls into storage, the spores of the fungus scatter, getting on a healthy planting material.
Therefore, it is so important to carefully select the bulbs for storage. However, the spread of dry rot is facilitated not only by the failure of the floriculturist, but the use of poor manure as a fertilizer of poor quality humus. If in the autumn bulbs with signs of fusariosis are identified, the site for 3-4 years becomes unsuitable for cultivation of this flower culture.
Another dangerous disease of the gladiolus, the treatment and prevention of which requires special attention - is gray, brown rot or botrytosis. The spread of the causative agent of the disease contributes to a cool wet weather, when fungus spores with wind and rain are carried from the soil and sick plants to healthy ones.
For a couple of weeks, reddish spots appear on the leaves of blossoming gladioli. The disease affects flowers, which quickly lose shape and decorativeness. If the rains do not stop, the stems rot, from which the rot will turn to corms. When digging out it is noticeable that the bottom of the sick bulb softens or completely fails.
On the image of the gladiolus disease, a photo bulb that can not be treated, with a through lesion of the core. Spoiled planting material is important to destroy, previously collecting from bulbs of children without signs of disease.
Sclerotinia, also called black rot, is more common on dense acidic soils and spreads with cold rain. At first the signs of the disease become noticeable on the browning foliage, then softens and the rotting stalk falls. On the affected tissue are visible black areas, inseminated with mushrooms. Rotting covers the corms, its white roots turn brown, softened and rotten.
On the surface of the gladiolus bulb itself is an illness whose treatment, like all fungal diseases, does not exists, makes itself felt by the formation of brown or dark-brown growth along the circumference stains.
As a result of a patient with sclerotinia, the planting material dries up, and the infection passes to the forming daughter corms. Therefore, the affected plants completely, including children, are destroyed.
Septoria by external signs resembles other fungal diseases of gladioli, as in the photo, while treatment, except for the prevention and complete destruction of damaged bulbs and spores containing fungus stems and leaves, no.
Bacterial diseases of gladiolus bulbs, their treatment and photos
To diseases of a bacterial nature carry a root cancer, a scab and a number of other problems which signs can be noticed more often on bulbs of gladioluses. Malicious bacteria enter the plant from the soil. With scab, they cause the formation of a kind of erosion on the body of the bulbs, and from the above-ground side the symptoms of this disease are not noticeable. Only the very soil can be seen brown or reddish spots, which without the adoption of agrotechnical measures grow and call for the rotting of the base of the stem.
The signs of the remaining gladiolus disease without treatment, as in the photo, are clearly visible when the bulbs are collected and dried.
Root cancers are also detected on already excavated bulbs as watery greenish-yellow formations that can be easily separated from the underlying tissue. The cause of the disease is the activity of bacteria that change the "program" of cells responsible for the formation of children.
Treatment of this disease of bulbs of gladiolus, as in the photo, does not exist, and the main struggle is in prevention, that is, the destruction of the bacterial flora and spreading pest diseases, including nematodes.
Viral diseases of gladioli
In recent years, flower growers are increasingly complaining about the spread of viral diseases of gladioli, the most famous of which is mosaic disease. It manifests itself as a chaotic alternation of light and dark spots or bands on the leaves, and then on the flowers of the plant.
Mosaic negatively affects not only the color, but also the growth of the gladiolus. Such a specimen lags behind neighboring plants, its inflorescences contain fewer buds, and the flowers themselves are smaller.
The bulb does not externally externally, but with insects that feed on gladiolus juices, and the inventory, the disease passes to healthy plants.
Viruses also cause such a disease of gladioli, as growth. Externally, a healthy bulb after planting forms extremely weak filamentous shoots or is not going to develop at all. The disease is not treated, and the planting material with its signs is destroyed.
Methods of fighting and treating diseases of gladioli
The main weapon in the fight against gladiolus diseases is targeted prevention, consisting of:
- in the development of agricultural technology;
- in the elimination of pests dangerous to flower culture;
- in the organization of proper selection and storage of bulbs.
The spread of fungal infections and all kinds of rotting contributes to the crowding of plantings, improper selection of fertilizers or soil type.
The abundance of nitrogen during flowering and closer to autumn, for example, can weaken the plant, prevent the onion from ripening in time and endanger its attack by bacteria and soil pests.
Therefore, in the second half of the vegetation, gladioli should be fed with potassium fertilizers with a minimal addition of nitrogen and phosphorus.
In order not to expose plants to the risk of infection with non-treatable diseases, gladioli can be planted after a deep digging of the soil. It is useful if marigolds, calendula, nasturtiums, parsley grew on the site before. These plants gently and safely disinfect the soil, repelling soil pests, often spreading bacterial diseases.
To the greatest extent this applies to such pest-bearing gladioli spreading disease, as depicted in the photo wireworm, various types of nematodes, and larvae of the horseshoe.
Newly purchased bulbs should not be immediately planted with already tested planting material. First, such gladioli sent to quarantine, that is, separated from the main plantation site.
It is important to plant flowers in time, otherwise:
- in the overheated soil the root formation is slower, the gladiolus looks oppressed, lags behind in growth and often becomes an easy prey for pests;
- in a cold ground, the plant is threatened with pathogens of rot.
As an effective measure against disease use regular loosening of the soil under planting, the introduction of supporting growth of fertilizing and watering.
To disinfect the area after the gladiolus, the soil is spilled with a 2% solution of copper sulfate. Categorically it is impossible to delay the harvesting of bulbs, which are threatened not only by freezing, but also penetration into the larvae of soil pests, fungi and bacterial flora.
How to treat gladioli before planting from disease
If there are no worrying symptoms, but externally the corms after storage are healthy, than to treat gladioli before planting from diseases?
As a preventive measure, the corms selected for planting are soaked for half an hour in a dense pink solution of potassium permanganate. From the danger of fungal infection, bathing bulbs in a slightly blue solution of copper sulfate helps.
After harvesting, the non-dried bulbs can be rinsed and for a few minutes filled with hot water, when it cools, repeat the procedure. The optimum temperature is 45-55 degrees. Then, cold water treatment followed by another rinse. Ordinary water will help to remove fungi from bulbs, wash the places of accumulation of bacteria, get rid of nematodes and thrips.
Before planting corms for 18 hours immersed in a solution of thiourea, a solution that works as a fertilizer and an effective fungicide. This product cleans and disinfects bulbs with a weak degree of infection with fungal infections.
From the second half of July the plants are treated twice or thrice with an interval of 1-2 weeks with a 2% solution of carbophos. An excellent prophylaxis against the fungus is spraying gladioli with a solution of copper chloride at a rate of 5 grams per bucket of water.
Treatment of gladioli from disease before planting - video