A rose is a beautiful, but rather capricious flower in terms of care. Numerous pests and diseases can undermine his "well-being", and in serious cases lead to death. Therefore, any grower growing roses should know the basic agricultural techniques and methods of protecting plants from pathogens and various pests. In this article, we will consider the following topic: "Roses: Disease and Treatment."
In general, all rose diseases are classified as non-infectious and infectious, and the latter, in turn, can be caused by viruses, bacteria or fungi. The most dangerous are the fungal diseases of roses, such as powdery mildew, gray rot, black spotting, infectious burns, powdery mildew and rust.
Roses: diseases and treatment of fungal diseases
Powdery mildew is considered one of the most serious diseases of roses, the causative agent of which is the fungus sph. pannosa lev. The disease can be recognized by the characteristic spider white or powdery coating on leaves, shoots, buds. With the development of the disease, numerous spores of the fungus form, which are carried by the wind over a large area. The flower quickly withers away: the leaves dry up and crumble, the shoots die off, and as a result, the plant can die without surviving wintering and rose disease (the photo shows the defeat of the flower with powdery mildew).
To prevent damage to the plant by the fungus, periodic prevention should be carried out:
- treat plants with infusion of ash (infused for 5 days: 1 tbsp. l. per 10 l of water);
- spray with mullein infusion;
- treat with solutions of potassium permanganate (2.5 g per 10 l) and soda ash (40 g of soda and soap and 10 l of water).
When the first signs of fungal infection appear, the rose should be treated with a solution of copper sulfate 1% and be sure to trim the diseased areas. Gray rot is another severe fungal infection that affects mainly buds and pedicels of roses. Most often, hybrid tea rose and floribunda are affected. The causative agent of the disease is Botris cinerea pers. The disease looks like a gray coating on parts of a plant. Methods of prevention and treatment are similar to the technique of getting rid of powdery mildew.
Roses: diseases and treatment. Infectious lesions
Black spotting (pathogen Marssionina rosae) is another of the severe fungal infections affecting flower leaves. Brown spots appear on them, blackening later. Bubbles form on these spots, and eventually the leaves fall off. In the absence of proper care, a rose can lose most of its foliage. They struggle with black spotting in the same way as with other diseases that arise due to fungi.
An infectious burn caused by Cniothyrium wernsdorffiae is more likely to occur in plants that are exposed to excessive moisture and elevated temperatures in winter shelters. The disease can be recognized by characteristic spots of brown color with a red border. To prevent the disease, it is necessary to cover roses for the winter only in dry weather, and also treat them with copper preparations. In addition, throughout the entire growing season should monitor roses and remove all affected areas.
Rust of roses is a disease that affects almost all parts of the plant. As a rule, repair varieties suffer from this infection.
Roses: diseases and treatment. Non-infectious lesions
Often the poor health of the plant and even its death can be a consequence of violations of diet and watering. One of the reasons for yellowing of leaves and drying of their edges is a lack of potassium. With a serious deficit, the leaves may acquire a reddish-violet hue. Subsequently, not only the leaves die, but also the stems of the flowers.
As a rule, a lack of this element is observed in plants growing on peaty and sandy soils. The solution to this problem is to fertilize roses with potash fertilizers (kalimagnesia, potassium sulfate or complex supplement). The deficiency of another trace element - magnesium - manifests itself as discolored spots formed on old leaves. Often magnesium deficiency occurs in plants grown in acidic soils. The treatment consists in the application of ash and complex fertilizers. Another serious nuisance is the lack of iron. It can be recognized by the yellowing of the leaves, which starts from the edges. If the disease progresses, they may become milky white and fall off.
The fight against iron deficiency consists in the introduction of organic matter (rapidly decomposing) and acidifying fertilizers, as well as in the feeding of iron preparations, for example, will help Kemira Universal. A lack of calcium also affects the development of the plant: its root system is weak, the stems gradually die, the buds do not open, and the leaves curl and bend. It is possible to fill the deficiency of an important element using calcium nitrate. So, we have listed the main infectious and non-infectious problems of the rose. The diseases and treatment of plants grown at home, we will consider further. In fact, an indoor flower can easily die from the same pathogens of infections or breach of growing conditions, like plants of open ground.
Rose home: care, disease, pests
Room beauty is often struck by rust, powdery mildew, black spotting, downy mildew. To treat powdery mildew, you can use a solution of soda (2 tsp. Per 1 liter of water). During the procedure, it is necessary to cover the soil with polyethylene, so as not to damage the roots. Often indoor roses are attacked by pests such as spider mites, rose aphids and thrips. For treatment, special insecticidal preparations are used.