A field like a yellow carpet against a blue sky always attracted the attention of passers-by. It is a culture that not only delights with its picturesque view, but also gives a lot of healthy products, the first of which is seeds. In a matter of days, a farmer can see the exact opposite picture due to a sunflower disease. Withered leaves and wilted baskets of plants signal loss of crop. Those who are going to start cultivating this crop need to know what difficulties they may encounter when growing it. The following is information on what diseases and pests a plant can be affected, and how to deal with them.
Causes of disease
How widespread the spread of sunflower disease depends on weather conditions and the area where the crop grows. High humidity and heat create suitable conditions for the development of microorganisms. They can affect both the plant as a whole and its individual parts.
Poor harvesting leads to the multiplication of pests. When there are a lot of sunflower residues in the fields, this attracts insects.
Another reason is a violation of agricultural technology. This includes the rules for planting crops, timely preventative treatment of plants with fungicides and weed harvesting.
Loss in the crop can be sustained due to the wrong choice of sunflower variety. For example, in regions where the moth “dominates”, it is better to plant a shell-like sunflower, where the basket structure will serve as protection from pests. Seeds in it are located very densely and are practically not affected by larvae.
Common diseases
The task of protecting a popular culture is complicated by the fact that there are too many fungal diseases. Since there are about 50 species, you should pay attention to the most common diseases of sunflower.
Common diseases include: phomopsis, downy mildew, white and gray rot.
Despite the fact that there are hybrid varieties of sunflower, it is not yet possible to gain a final victory in the fight against plant infections. Therefore, everything possible must be done to protect the future crop as much as possible from sunflower diseases. The following are some guidelines.
- Certain varieties of sunflowers need to be isolated from each other to avoid unwanted pollination. For this purpose, create space or divide the fields with forestation.
- In autumn, plowing is carried out with the help of autumnal tools. This method allows you to deeply loosen the earth and disturb the vital activity of pathogenic microorganisms.
- It is important to carefully remove the tops and destroy the scavenger. Contaminated residues are an excellent shelter for bacteria - by the next season they will be much larger.
- Since many fungi live in the soil, protecting the sunflower from diseases will help treat the field with fungicides.
How to protect seedlings
The diseases of sunflower seedlings include: mold, root rot and various types of bacteria. Pathogens penetrate the sprouts and small shoots. The accumulation of pathogens is carried out in the soil and seeds. With a large contamination of the soil and planting material, seedlings can either die immediately or not rise at all.
Young plants can be harmed by black spotting, which is recognized by brown spots with a light border. Traces of an indefinite form appear on the stem, and subsequently on the leaves. If the plant does not die, then it looks frail and already full development does not occur. With this disease, the leaves and the stem dry in sunflower, which in turn affects the quality and quantity of seeds. Crop in this case is reduced by 20%, and the degree of oiliness - by 10-12%.
In order to prevent rot and mold of future seedlings, the Superwin protective agent is used, with which planting material is processed.
Gray rot
The decay of a sunflower basket provokes a gray mold - Botritis. Deformed baskets with oily spots on the back can be observed everywhere. The reason for this is the persistence of the infection. It lives in the soil for a very long time and can penetrate into sunflower seeds. On the leaves, the fungus appears as a gray plaque. Infection contributes to the softening of the lesion and over time these areas rot.
Gray rot is able to knock down even hybrid varieties, so you can not sow sunflowers near swamps, rivers and in deep places. It is good when the direction of the rows is accompanied by wind. Before sowing the seeds must be processed.
Crops are treated with such tools as “Clinics Duo”, “Dominator” and “Chistopol”.
Fomopsis
The people call this disease gray spotting and as a rule it is localized on the stem. Manifestations in the form of spots are dangerous for the development of the plant and it is difficult to deal with them. Since phomopsis is considered a viral disease of sunflower, this complicates the process of measures taken to inhibit the growth of bacteria.
An increase in temperature, excessive rainfall and infected residues create favorable conditions for the fungus to form and spread.
To reduce the risk of disease, crops should be alternated and harvesting should be carried out efficiently after harvest.
White rot
This disease is characterized by a white coating in the form of a gun. Such manifestations can be called spontaneous, since they can emerge at any stage of plant development. Even new seedlings of sunflower disease can destroy immediately. Sclerotinia, as this disease is also called, develops in spring at a temperature of +15 ° C. With a later defeat, it is possible to save the baskets of sunflower, as some stems fall ill. But this is when the culture has already formed. When white moss covers the stems before flowering, it gradually thins the lesion and the plant breaks.
The basal form of a fungal infection is dangerous, because it inhibits the flow of necessary substances for plant nutrition.
Low temperatures, thickened plantings and clogged fields lead to white rot.
With this disease of sunflower, fungicides are not used, therefore, some measures must be taken to protect it. It is important to create good ventilation throughout the growing season. It is necessary to destroy weed in a timely manner and not to plant sunflowers too densely. To protect crops, use hybrid varieties of this crop. You should also destroy the affected plants mechanically.
Downy mildew
Infectious sunflower disease is characterized by a variety of its manifestations. Throughout the season, you can observe such paintings:
- At the first stage of development, the plants stop growing, the stem becomes thin. On abnormally small leaves, whitish spots appear along the entire length of the central vein. From the wrong side of the leaf, the fungal mycelium is clearly visible.
- Another symptom of the fungus's vital activity is expressed in the formation of angular spots that are light green in color and cover the front side of the leaf. Such manifestations contribute to the development of dwarfism.
- If the infection is located around the root system, then the sunflower reaches its maturity, but the activity of the fungus affects the quality of the seeds. Their number is reduced and a significant part of them are empty seeds, many of which are infected with fungal spores.
There are 5 types of powdery mildew disease. In this regard, we can expect the appearance and development of infection at any stage of plant vegetation. To protect crops from such an insidious defeat as powdery mildew, the field should be treated with the fungicide "Desaral Extra".
Aphid is a dangerous pest
Small aphids are capable of great harm. Reproduction of insects is too fast, and it can destroy the entire crop. Aphids feed on plant sap, resulting in its depletion, and then complete drying out. The secretions that it leaves on the leaves inhibit photosynthesis, and this affects the growth of sunflowers.
The presence of aphids is determined by the type of plant. At first it wrinkles, and the next thing to notice is yellow specks on the leaves, gradually increasing in size. A sticky coating appears on the back and the leaves curl.
Large weeds can serve as bridges for aphid migration to sunflower. Harvesting weeds will significantly reduce the number of harmful insects.
When applying fertilizers, it is important not to overdo it with nitrogen, as this will be a good bait for aphids.
The interval between crop rotation should be at least 3 years. During this time, the larvae die.
Other types of pests
Insects cause a lot of trouble, as they quickly spoil the plants. The most dangerous of them are: a sunflower ’moth, a cotton scoop, a meadow moth, a sunflower barbel, a tenon, a sand lazy. Moreover, each type of harmful insect has its own area of activity. Spikes and whiskers feed on the stems of the plant, the ognevka “regales” with seeds, and moths and spider mites spoil the leaves. Crickets of sunflower seedlings can be provoked by crickets, nutcrackers, weevils and scoops.
The sandy lag. Beetles harm the cotyledon and sunflower leaves, winter deep in the ground, and creep to the surface in spring.
To destroy these large pests, alkaline and calcareous substances are introduced into the soil.
The best way to protect yourself from procrastination is to treat the planting material with Fentyuram suspension. Beetles are afraid of this smell.
Sunflower Shiponoska. Insects live in the steppes and lay eggs under the sunflower peel. Inside the plant, the tongue-and-grooves make moves and feed on the contents of the stem.
Residues after harvesting should be burned, because tenon found in them shelters for wintering.
Meadow scoop. The insect destroys small shoots. The accumulation of larvae of scoops is found in the basal aerial part of the plant. They gnaw stems, as a result of which the sunflowers fall and the area with shoots looks thinned out. Females love clogged areas, as grass serves as a place for laying eggs.
Soil cultivation and weed control are effective pest control methods.
Insecticides for the destruction of scoops: "Decis", "Bazudin" and "Arrivre".
Meadow moth. Pests of this kind can cause enormous damage. They eat sunflower leaves too quickly . Moths are resistant to frost and live in the soil.
Get rid of the meadow pest will help the insecticide "Bi-58".
Seed damage
There are two main causes of diseases of sunflower seeds:
The disease originates from the ingress of planting material into an unfavorable environment. When sown in infected soil, healthy seeds are exposed to fungi and lose their properties. This in turn affects the development of the plant. Lesions of seed baskets with gray sclerotinia and dry rot contribute to the further development of infection. Thus, contaminated soil causes seed disease.
The second reason is increased humidity on the field and during harvesting of sunflower. If a lot of rain falls before harvesting, then the seeds become vulnerable to damage. Being on the same field, each basket of sunflower ripens in its own way. Seeds with different maturity when harvesting fall into one hopper, and for themselves create unsuitable conditions. Unripe residues contribute to temperature and moisture. Seeds lose their natural luster, and the core becomes dark.
Protection of planting material is an important factor in the cultivation of sunflower. The methods for treating the diseases described in this article help protect seeds as well. For example, soil treatment with fungicides and not thickened crops to some extent guarantee the safety of seeds. Of great importance is the choice of sunflower varieties.
Unusual seed application
Not everyone knows that germinated seeds are a cure. They include fatty acids, vegetable proteins, trace elements and vitamins. The content of tocopherol is a major factor in why sunflower seedlings from female diseases can be invaluable. They are used to treat infertility. For pregnant sprouts, they are useful in that they contain folic acid, which is necessary for the normal development of the embryo. Sprouts improve digestion and cleanse the body.
Conclusion
Sufficient knowledge about sunflower diseases and measures to combat them will help preserve the crop. Although crop yields often fall due to climatic conditions, it would be good for farmers who have experienced losses to review: are all agricultural practices compulsory. It is for this reason that cultivated plants become more vulnerable. The implementation of the necessary technologies is the protection of sunflower from pests and diseases.