Diseases and pests of wheat
In our country, wheat is one of the most common cereal crops grown on an industrial scale. Both agricultural enterprises and individual farmers are engaged in its production. Any threat to the harvest can lead to serious financial losses, and even become a blow to the wheat reserves of the entire state. This culture is very vulnerable to various diseases and pests. It is worth considering in more detail the description of threats and how to deal with them.
Diseases
Fungi, bacteria and viruses pose a serious threat to cereal crops. Farmers have to make a lot of efforts to protect the future crop. This struggle lasts throughout the entire ripening season, almost until the very harvest. And in order to have something to collect, you need to carefully examine the seedlings for possible diseases. If at least somewhere the slightest signs appear, it is necessary to take action as soon as possible.
Treatment is a complex process. It is much easier to carry out preventive treatment, because such a threat is easier to prevent than to cure.
But it is impossible to recognize the disease if you do not know what it is. It is worth considering a few of the most common examples.
- Septoria - it is a fungal disease known as white spot. It received the second name for the light spots that appear on the stems and leaves. Septoria is susceptible to both cultivated and wild plants. The causative agent is fungi of various kinds. This disease is characterized by the presence of spots throughout the plant.They have a yellowish tint, a dark rim and black pycnidia. To take a closer look at the plaque, you should use a magnifying glass.
Due to septoria, wheat seedlings begin to turn yellow and dry out, the grains grow small. And if the disease hit the wheat in the early stages, then the ears may even turn out to be fruitless.
- Fusarium spike - This is another fungal disease that spreads exclusively along the spikelet scales. It affects wheat and all other cereals grown in Russia and Europe. The causative agents of the disease are imperfect types of fungi. You can identify the disease by a pinkish coating formed on the spikelets and grain. Growing, fungi glue the grains into dense lumps. In this case, the spreaders of the infection are located in the seeds, tops and even in the soil.
- Fusarium root rot - This is a very dangerous fungal disease that affects the root system of plants. As a result of exposure to fungi, the roots can rot and begin to die. With a strong and early impact of the disease, the culture dies even before the first shoots sprout. The presence of infection in germinated crops can be determined by the lower part of the stems, which will turn brown. The upper part and leaves will begin to turn white, a pinkish pattern will appear on them. Fusarium grains have the same, while healthy ones retain their green color. Fusarium root rot is capable of turning into ear fusarium.
- common root rot very similar to fusarium, because it also affects the root system. You can determine by the lower base of the stems, which begin to darken. With later lesions, brown oblong spots appear on the leaves. Spikelet scales acquire the same color.Grains in the disease grow small.
- ophiodisease rot occurs when there is too much moisture in the soil. It affects the roots and leads to the death of plants. During the period of full shoots, the root system turns black and begins to rot, and when the heading phase begins, the productive stems die off. The presence of the disease can be determined by the low growth of wheat and the white color of the upper part of the stem. The lower parts turn brown, and black dots appear on the leaf sheaths. The grain is formed small.
- Dark brown spotting is a fungal disease of grain crops, most often affecting barley and wheat. It is also known as black germ because the grains of diseased shoots turn dark in color. The disease is determined by brown spikelet scales. The roots begin to rot, and the leaves become covered with oblong spots, which can be either dark or light brown.
- pyrenophorosis is a cereal disease known as yellow spot. This is one of the most common diseases that affects more than 60 plant species. Yellowish or light brown round spots appear on the leaves, while their center is lighter. In rainy weather, you can see an inconspicuous spore coating, which disappears when dried.
- hard smut - This is a common disease in Russia that affects wheat. The causative agent is a type of fungus with morphological features of teliospores. The disease can be recognized only at the stage of milk ripeness of the grain. Diseased ears are flattened, and their scales are pushed aside. If you crush one spikelet, then instead of a white liquid, a grayish one stands out from it.
Pests
The second main threat to wheat is numerous pests. Among them are the following:
- aphid;
- beetles;
- fleas;
- gall midge;
- sawflies;
- thrips;
- flies.
The list of subspecies is quite wide and varied. It is worth considering a few examples.
- common grass aphid - These are small insects with a round body only 3 millimeters long. They have thin legs, antennae, a tail, and two appendages called sap tubes. In this subspecies, these tubes are almost twice as long as the tail. During the warm seasons, aphids can breed up to 15 generations. In winter, small larvae can be found on fodder plants, from which the female is hatched. She produces offspring by live birth.
This is a common subspecies in the warm regions of our country, which is not prone to migration.
- Bread beetles feed on cereal crops, causing serious damage to the crop. They are common in the Volga region and the Central Black Earth region of the country, they have antennae on their heads, as well as wings and elytra. Their sizes differ depending on the accessory, namely:
- bread kuzka - this is the largest, reaches 16 millimeters in length, poses the greatest threat to the crop, is distinguished by dark chestnut elytra;
- crusader got its name for the black cross-shaped spot on the yellow-brown elytra, has an average size of 10 to 13 millimeters;
- krasun - this is the smallest subspecies, whose maximum length does not exceed 12 millimeters; it is distinguished by yellowish elytra without spots, but with light hairs.
Important! Harm to the crop can be caused not only by adult beetles, but also by larvae. The former operate on crops in the spring, the latter begin raids in early summer. The main activity takes place during the daytime.
- Bread fleas - These are small bugs with an oval body shape. They move by means of large leaps and attack crops in early spring. They are divided into two types.
- leafy also known as striped. Their dimensions do not exceed two millimeters. They are widespread in all regions of Russia and far beyond its borders. This subspecies feeds on leaves, gnawing numerous holes in them, because of which the plants begin to wither and die.
- stem can be either ordinary (from one and a half to two millimeters in length) or large (up to three millimeters in length). They are also distributed throughout the country, but are most active in the Volga region and the Central Black Earth region. The larvae cause the greatest harm when shoots appear. They gnaw their way through the stems. Seedlings begin to turn yellow and wither.
Control measures
As mentioned above, the threat is easier to prevent than to get rid of it later. Before sowing, it is recommended to carry out the following preventive measures:
- after harvesting, plowing should be carried out to destroy pathogens and pests that like to winter in the soil, which will reduce the risk of infection of the next crop;
- it is necessary to observe the optimal sowing dates, for example, many diseases develop better on winter wheat, with which they roam safely in other crops; the main thing is to deprive pathogens of favorable conditions for the spread of infection;
- if there is a possibility that a certain area is infected, you should not plant crops next to it;
- before planting, the seed material should be treated with special substances that will either protect seedlings from diseases or heal infected seeds;
- do not forget to carry out chemical treatment of crops.
However regular prevention does not guarantee complete protection against various threats. It pays to always be ready. Of course, in most cases, fungicide treatment saves from diseases and insects.But it is better to find out the specific symptoms in order to understand exactly what measures need to be taken against the disease.
For more information about diseases of cereals, see the following video.