Despite the fact that most varieties of barley are resistant, there is always the possibility of damage to crops by diseases and pests. The reason for this may be violations of the technology of cultivation or crop rotation. We will talk in more detail about the most common and dangerous pests and diseases of barley, the harm they cause and the methods of control in this article.
The main diseases and pests of barley
Barley diseases and pests can be divided into several groups:
- root system;
- autonomic aboveground organs;
- smut;
- rust;
- spike diseases.
Brown rust
This disease provokes a basidiomycete. Grain infection can be observed throughout the growing season. Symptoms appear on the upper side of the leaves and vaginas of barley and look as follows:
- single, oval, light brown uredinia;
- black pustules - telia.
This is a harmful disease that leads to the disruption of vital physiological and chemical processes - the affected leaves die off, the grains form punctured and have reduced germination.
Brown rust control methods are as follows:
- Agrotechnical:
- compliance with regional recommendations for cultivation;
- weed control;
- the use of pathogen-tolerant varieties;
- isolation of spring and winter fields.
- Chemical - treatment of vegetative crops with fungicides - Kansel (KS), instructions for use are given on the packaging.
Stem rust
The disease manifests itself in the steppe zones in the late crops, is provoked by fungi. Stem rust affects leaves, stems, ears of corn and leaf sheaths. Manifested by rusty-brown oblong rows.
When affected by this rust in barley:
- drought resistance decreases;
- punctured grains are formed;
- water balance is disturbed;
- growth and development are inhibited.
In the event of an outbreak of stem rust, use spraying of barley seed with 80% cineb (5 kg / ha) or anilate (5 kg / ha) with an adhesive (0.1-0.2 kg). The flow rate of the working fluid is 100 l / ha. If necessary, repeat the treatment after 8-10 days.
Agrotechnical measures:
- crop rotation compliance;
- spatial isolation of winter from spring;
- sowing at the optimum time;
- cleaning in a short time;
- destruction of intermediate plants;
- air-thermal and solar heating of seeds.
Dwarf rust
This is the name of the dioecious mushroom, which affects winter and spring varieties of barley. During the growing season, the infection is spread by uredospores through the air. The pathogen is preserved in the form of uredomycelia in barley and carrion crops.
The initial stage of the disease is characterized by the appearance of small pustules of a light yellow color on the leaves and sheaths of barley. It develops with the following factors:
- the presence of an intermediate host;
- the presence of drip moisture;
- air temperature + 15-18 degrees.
The disease causes a slowdown in photosynthesis, metabolism, and water imbalance, and the quality of the grains deteriorates. The defeat leads to a decrease in productivity and worsening winter hardiness.
Agrotechnical protection measures:
- compliance with crop rotation rules;
- the use of resistant varieties;
- micronutrient seed treatment;
- application of mineral fertilizers with a high content of potassium and phosphorus.
From chemicals for treating dwarf rust, a number of effective drugs have been developed that can be bought at the store and used in accordance with the instructions:
- Alpha-Tebusol fungicide;
- Flutrivit;
- Polygard.
Fusarium spike
Barley becomes infected during flowering and ripening. Typical symptoms are characterized by the appearance of pink-red or pale pink plaque on the cereal flakes, which is a mycelium and sporulation of the pathogen.
The grain affected by fusarium becomes whitish, has a dirty brown tint, a pink-orange coating may appear. The disease affects the sowing qualities of barley - they are reduced or completely lost, mycotoxins accumulate in the grain.
Fusarium develops due to wet weather during the heading period, and the affected grain remains are the source.
Protective measures:
- alternation of crops with a break in rotation for at least 1 year;
- reduction of plant debris on the soil surface;
- sowing seeds in well-prepared soil;
- seed treatment before sowing.
Early fusarium infection must be controlled during flowering - be sure to carry out fungicidal treatment of crops. For this, Tebuconazole (instructions on the package) is suitable.
Root rot
Like other crops, barley also undergoes root rot. This disease is ubiquitous in barley cultivation regions. The danger is that young shoots are affected. Losing the ability to grow, they rot and die.
Symptoms
- plant stems and tops become brownish-reddish;
- the underground stem internode becomes brown;
- the aerial part of the plant darkens;
- diseased plants are easy to pull out.
Disease Protection:
- seed dressing;
- crop rotation compliance;
- the use of biological preparations - Fitosporin-M, Gamair, Gliokladin.
Powdery mildew
A common disease in areas of growing spring barley. The pathogen is well preserved in the winter in the form of mycelium in the axils of the leaves of the plant. In affected plant areas, pathogen cleistotia may remain.
At the initial stage of infection, the leaves and stems are covered with a cobwebbed coating, which gradually changes the structure and becomes more dense. This plaque contains spores of the fungus, which can spread through the air, which causes infection of other plants.
The disease can develop due to the high density of crops, high humidity and temperature within +20 degrees.
Agrotechnical control measures:
- spatial isolation of crops;
- compliance with crop rotation rules;
- cultivation of resistant varieties;
- sowing at the optimum time;
- fertilizer application.
Dusty smut of barley
The causative agent (fungus) is stored in the form of mycelium inside the caryopsis, infecting it during the flowering period. Plants infected with this disease develop faster than healthy ones. Infected barley begins to bloom before the main field, and the disease manifests itself during the heading period.
The ears that were hit have a charred appearance due to the destruction of the floral parts and the covering parts of the spikelets. Only the core remains intact.
Infection conditions:
- prolonged flowering of barley;
- relatively wet weather;
- moderate temperature (about 23 degrees);
- wind contributes to the spread of spores.
In infected barley, the yield of grain sharply decreases, it has a lower mass, and emptyness can be observed. The plant weakly grows, the quality of the crop decreases.
Control measures:
- seed dressing;
- compliance with the timing of sowing;
- compliance with crop rotation rules.
The most effective drugs to combat this disease are Serticore 050 k.s. (0.75-1.0 l / ha), Dividend Star 036 (1.0-1.25 l / ha).
Dark brown spotting
The first signs appear in spring on the seedlings in the form of oval brown spots with a clear chlorotic border. Spots can develop on leaves and leaf sheaths at all stages of a plant’s vegetation.
With severe damage, the spots begin to merge and cover the entire sheet completely. After that, in the presence of favorable weather conditions, the fungus affects the ear and grain, causing a symptom of a black embryo.
Control measures:
- destruction of plant debris;
- correct crop rotation;
- cultivation of resistant varieties;
- seed treatment with drugs: Benefis ME, Polaris, Scarlet, Tebu 60, Tuareg;
- use of fungicides: Title Duo, Triad, Capella.
Striped spotting
The causative agent affects barley from the beginning of seedlings to ripening. During the growing season, the infection spreads by conidia by airborne droplets. It is preserved in the form of conidia, mycelium on plant debris, in soil and seeds.
In the seedling phase, pale yellow spots begin to appear on the leaves. Gradually lengthening, they merge into light brown stripes with a narrow purple border. The spots are then covered with an olive-brown bloom of conidial sporulation.
Symptoms of striped spotting appear on each shoot. In the most severe degree, the disease makes itself felt during flowering and pouring grain. The affected tissue cracks, and the leaves are torn lengthwise into 2-3 parts, after which they dry out.
Against striped spotting, you can use:
- Altin - spraying during the growing season, flow rate - 300l / ha;
- Avakss - spraying during the growing season, 300 l / ha.
Agrotechnical measures:
- cultivation of resistant varieties;
- optimal sowing dates;
- crop rotation compliance;
- the introduction of phosphorus-potassium fertilizers in a mixture with trace elements.
Net spotting
The disease is caused by an imperfect fungus hyphomycete and begins to develop in the tillering phase, reaching its maximum during flowering and pouring grain. This is one of the most harmful diseases of barley.
Based on the symptoms, 2 types of the pathogen are distinguished - mesh and spotted, and both types can occur both individually and together:
- with mesh type necrosis with a mesh pattern appears, surrounded by light green, yellowing areas;
- spotty type characterized by rectangular, oval or dotted, dark brown or light colored necrosis.
If the disease develops strongly, then the affected areas merge, and the leaves begin to die.
The following fungicides can be used against net spotting: Kornet KS, Crossbow KS, Balista KE, systemic fungicide disinfectant Fast and the Furious KS.
Agrotechnical measures:
- compliance with spatial isolation (more than 1 km) between barley crops;
- carry out spring harrowing (loosening) of herbs with the obligatory burning of all dragging on roadsides of fields and roads;
- crop rotation compliance.
Reticulated helminthosporiasis
The pathogen is stored in the soil and on plant debris in the form of a mycelium for no more than one year, and spores located between the flakes of grain - up to 5 years. The optimal conditions for the development of the disease are a temperature of 15-25 degrees and 100% humidity.
Infection with a mesh form causes the appearance of either dark brown stripes on the germinal plates, or spots of gray-white color, having an oval shape in the center of the sheet.
If the infection occurred on adult plants, then small brown dots appear in diameter, which gradually turn into dark necrotic stripes.
Control measures:
- use of relatively resistant varieties;
- crop rotation;
- stubble destruction;
- fungicide treatment of winter cereal crops in the autumn or in the period of spring regrowth - Tinazol (0.5 l / ha), Virtuoso (0.5 l / ha), Berkut (1.0 l / ha).
Rhinosporiosis
Another name for the disease is bordering spotting. This is a leaf spotting disease. The leaves of the lower tiers are infected, but in the case of a strong degree of infection, it spreads to the flag leaf and spike.
The first symptoms are dirty green, watery, oblong spots, which gradually become faded gray. Necrotic spots in the last stage have a distinct dark brown border that separates them from healthy tissue.
The development of rhinosporiasis is possible at temperatures from +2 to +27 and air humidity above 95%. Spores are spread by raindrops falling on them. Symptoms of the disease can be seen after 8 days from the moment of infection.
Control measures:
- destruction of plant debris;
- crop rotation compliance;
- cereal weed control;
- isolation of barley fields from perennial grasses;
- treatment of vegetative plants with fungicides - Title 390 KKR, Title Duo KKR, Triad KKR, Capella ME.
Grass aphid
The pest belongs to the Companion wing order and is widespread in the Central Black Earth, North Caucasian regions, in the south of Siberia and the Far East.
The body of the aphid is up to 3 mm long; its color may be yellowish, light or grayish-green. The legs and antennas are thin. Adult individuals are represented by wingless and winged forms.
The pest accumulates on the young upper leaves. As a result of the suction of juices, discolored spots appear on the leaves. With severe damage, the leaves turn yellow and dry, the shoot does not roll out.
Aphids populate the ears and take the juice from different parts, which causes partial whiteness and emptyness, and during the filling season - weakness, unfulfilled grains. In the northern regions, aphid abundance is facilitated by hot, dry weather; in the southern regions, warm and moderately humid.
Agrotechnical control measures:
- stubble peeling;
- autumn plowing;
- sowing winter crops in optimal terms;
- weed control.
Also, plants need to be treated in a timely manner with grain pyrethroids, organophosphorus compounds and other insecticides:
- universal insecticide disinfectant - Imidalite TPS;
- systemic insecticide - Clonrin, CE;
- broad-spectrum insecticide - Samurai Super, CE; Tsiperus, CE;
- 3rd generation pyrethroid - Taran VE.
Bread Striped Flea
An oblong, slightly convex beetle of black color. Head and pronotum are greenish with a blue metallic tint. They develop in one generation, winter in the upper soil layer or under fallen leaves. Awaken in mid-April and first feed on winter cereals. After emergence of spring crops, insects migrate to them.
Adult individuals cause significant damage by damaging the leaves of barley, which ultimately leads to yellowing and drying out of the plant. To prevent harm and limit the number of fleas, take the following measures:
- as early as possible sowing barley;
- with a high number of fleas in the fields, insecticides are used (Volley, Karachar, Faskord);
- before sowing an insecticide spray the seeds;
- weed control along the perimeter of sown areas.
Gray grain scoop
A butterfly whose front wings are gray or dark gray with an admixture of brown shades. The color of the dorsal half of the body is brown, the abdominal surface is light. This is a widespread pest, but mass reproduction and harm can be observed in some areas of the Trans-Urals, Siberia and Altai Territory.
Caterpillars of winter scoops overwinter in soil, at shallow depth, in earthen cocoons. They leave wintering in late April - early May, with an average daily air temperature of +3 .. + 9 degrees. For some time they feed on seedlings of weeds and cereals, after which they pupate in the soil.
Caterpillars feed on the grain, eat it away and leave only the outer shell filled with excrement and cobwebs. You can fight with the following methods:
- single-phase or two-phase timely harvesting;
- autumn plowing and stubble peeling;
- optimal sowing dates;
- spraying with biological products: a suspension of Dendrobacillin (1.5 kg / ha), a solution of paste Dendrobacillin (3 kg / ha), a solution of Lepidocide (1 kg / ha).
Yellow cereal gall midge
This is a small mosquito 1.5-2 mm long, with a black head and a light yellow body. Larva is legless, fusiform, lemon yellow, up to 3 mm long.
Distributed in the regions of the North Caucasus, Central Black Earth and Volga. Larvae winter in a silky cocoon, in the soil, and in spring pass into the upper layers of the soil, after which they pupate.
From the eggs laid by the female for flower scales, larvae are formed that feed on the ovary, less often - a developing caryopsis. Such damage causes voidness and reduced grain mass.
Protective measures:
- crop rotation compliance;
- post-harvest stubble peeling;
- deep plowing;
- spraying with Karate Zeon in the earing phase.
Bread sawfly
The larva hibernates in the lower part of the stubble in translucent cocoons and pupates in spring. At the beginning of summer, barley enters the tube. The female, using a saw-shaped ovipositor, lays eggs, often in the upper internode, in stems with a hollow straw.
The larva feeds on the inside of the stem, gnaws knots, makes ring cuts at the base of the straw in the lower part of the stem. Damage causes withering of the central leaf, white-eyed.
Deep sawing with stubble fixation helps fight sawflies. You also need to use predecessors that suppress the number of sawflies - legumes, corn for silage. Insecticides can be used against adults.
Wheat thrips
The thrips larvae winter in the soil, plant debris, on the scavenger, on the leaves of winter barley. In cereal plants, the pest sucks the juice from the ear. Damaged upper parts of barley look whitish and shabby, then dry up. Thrips causes grafts and grains.
Control measures:
- crop rotation compliance;
- destruction of carrion;
- stubble peeling and deep autumnal plowing immediately after harvesting;
- insecticide treatment - Borey Neo, Vanteks, Bishka KE, Binom.
Barley fly
Small insects are classified as “secretive” - they are settled in the stalks of grain seedlings. The fly is adapted to arid conditions and can additionally feed on flowers. For laying eggs, prefers sprouts of barley.
About a week after laying the eggs, larvae appear that penetrate into the middle of the stem, where they settle and begin to feed on the central leaves of the plant, which causes cereal death.
Methods of struggle:
- grain calibration before sowing;
- selection of the most resistant varieties;
- balanced fertilizer application;
- placement after legumes or row crops;
- post-harvest work;
- use of insecticides by spraying (Cruiser, Celest Top).
How to protect barley from disease?
Protecting crops from diseases helps to achieve a healthy crop - only using an integrated approach can achieve excellent results in a short time.
Pay attention to the variety of agricultural activities:
- compliance with the rules and terms of crop rotation;
- active weed control;
- high-quality tillage;
- meeting harvest dates;
- competent selection of trace elements;
- the use of disinfectants, fungicides, insecticides, growth regulators and other drugs.
Despite the large number of existing pests and diseases that can destroy your crop, with proper observance of agricultural rules of cultivation, you can avoid this. If the situation is neglected, chemical and biological preparations will come to the rescue.
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