Leaf roller on wheat. Cereal leaf roller. All terms on
Cereal leaf roller - Cnephasia pascuana Hbn. Butterfly of the leafroller family. Distributed in the forest-steppe and steppe zones of the European part of the USSR. Damages mainly wheat and barley.
The wingspan of the butterfly is 14–20 mm. The color of the wings and body is gray; on the front wings there are two oblique dark gray stripes. Caterpillar up to 10 mm long, yellowish-gray, with dark spots. The flight of butterflies begins in June - July. Females lay eggs in cracks in the bark of trees in forest plantations. The caterpillars overwinter under the bark or in the soil. The caterpillars are polyphagous, and in the spring they crawl from their wintering grounds to the crops. Caterpillars of younger instars gnaw out oval mines in the leaves or mines elongated along the veins, caterpillars of older instars gnaw at the inside of the leaf sheath or the ear hidden in the leaf; before pupation, they gnaw through the straw 6–8 cm below the ear, which dries out and turns yellow. Damage is concentrated along the edges of crops, near forest belts. Pupation occurs on food plants. 1 generation develops per year.
Protection measures: reseeding along the edges of fields occupied by grain crops, legume-cereal grass mixtures that are sparsely populated by caterpillars; marginal treatment of fields with insecticides in the phase of plant emergence with a population of over 50 caterpillars per 1 m2.
All terms on
Sorrel leaf beetle - Gastroidea viridula Deg. Beetle of the leaf beetle family. Distributed in the European part of the USSR, Western Siberia, the Caucasus and Central Asia. ...
Onion leaf beetle - Lilio ceris merdigera L. Beetle of the leaf beetle family. Distributed in the European part of the USSR, the Caucasus, Central Asia, Siberia...
Many insect pests are adapted to feed on cereal crops. Some of them are polyphagous, while others feed exclusively on grains.
In total, more than 300 species of insects feed on cereal crops. Some of them pose a particular problem for agriculture, since they cause the greatest damage to crops.
Swedish fly
Delphacids are small jumping insects, popularly called pigs. You can find out what these pests eat by following the link.
Adults have an ovoid body shape, up to 1 cm in length. Insects overwinter under the snow and lay eggs in the spring. Larvae emerge from them, turning into 
adults.
The larvae infest wheat, barley and other grain crops. Adults also feed on cereals. The activity of the pest leads to a decrease in the quality and quantity of the crop.
Fighting the sharp-headed bug:
- peeling stubble and plowing fields after harvesting;
- use of insecticides.
Cereal crops, which are of great economic importance and occupy vast areas, require proper care. Knowledge of pest control methods and their timely application will help avoid losses in the quality and quantity of the crop that these insects can cause.
Cnephasia pascuana Hbn.
Morphology of the cereal budworm
The size of the butterfly reaches from 16 to 18 mm. The front wings are ash-gray in color, the hind wings are gray-brown or ash-gray.
The egg is about 0.5 mm in size, oval-elliptical in shape, color ranges from pale orange to red.
Caterpillars that have just hatched reach a size of 0.6-1.0 mm. The almost transparent body is light orange in color, the larva's head is light brown. With age, the body color changes to light green, and the head becomes black. Having reached the fifth instar, the caterpillar changes color again. Its head becomes light brown with a shine, its body loses its pale green color and becomes yellow. At the last instar, the caterpillar reaches a size of 10 to 12 mm. Caterpillars go through six instars.
The size of the pupa is 5-8 mm, has a mummy-like appearance, and is colored yellow or light brown. There are also two processes on the cremaster. The pupa is covered in a soft cobweb cocoon.
Developmental biology of the cereal budworm
Throughout the year, the cereal leaf roller develops in one generation.
The flight of butterflies is observed from June to July. Butterflies accumulate mainly at the edges of fields in forest belts, groves, on dry plants, and the like. During the daytime, butterflies hide in a wide variety of shelters.
They are active in the evening, mating and laying eggs. Females lay eggs on tree trunks, placing them singly, in groups or in a chain in cracks, or under lichens.
The fertility of one female is from 80 to 150 eggs. Embryonic development lasts about 10-15 days. The caterpillars hatch from the third decade of July until mid-August.
Having hatched, the caterpillars do not feed, but immediately hide in trees, under lichens, moss and in cracks, where they remain covered in a cocoon for the winter.
With the arrival of spring, when the average daily temperature reaches 10-12°C, the caterpillars emerge from diapause and are carried on cobwebs by air currents to the crops. This process lasts about two to three weeks and coincides in time with the regrowth and emergence of cereal plants into the tube. This occurs in April or early May and depends on weather conditions.
The caterpillars mainly inhabit the edge strips of fields up to 200 meters wide. Pupae are formed in the axil of the last leaf. Pupation occurs during the heading phase and ends in the phase of milky or milky-waxy ripeness of the grain. The duration of development of the pupa is 10-15 days.
Hessian fly
Scott Bauer, USDA Agricultural Research Service
Adult larvae overwinter in the stems of winter wheat and cereal weeds. In the spring they pupate and after 10–12 days the flies emerge (late April - early May). Fertility - from 50 to 500 eggs. During the year it develops in 3–4 generations. The first and second generations develop on spring, winter wheat, barley, the fourth - on seedlings of winter wheat, barley. The phase of plant development does not matter for fly colonization. On seedlings damaged by a fly, the apical leaf stops growing, the stem turns yellow and dries out. The stem, damaged during the phase of exiting the tube - grain filling, bends, the field looks like it has been damaged by hail.
Protection measures
Post-harvest stubble peeling with immediate plowing destroys Hessian fly larvae remaining in the field. Destruction of carrion. Elimination of sowing wheat on wheat. Treatment of seeds with the preparation KRUIZER (0.8–1.0 l/t) or treatment of foci of Hessian fly infestation with the insecticide EFORIYA (0.1–0.2 l/ha) during the tillering phase against the autumn generation.
Contarinia tritici
Most often damages wheat. The larvae overwinter in round white cocoons in the soil. In the spring they leave the cocoon, move to the upper layers of the soil, and pupate. The emergence of gall midges occurs at the end of the tube emergence - before heading of winter crops and lasts 2–4 weeks. Gall midges are most active in the evening hours. Before sunset, they rise above the plants and form “swarms” that are easily transported by air currents to neighboring areas. Females lay eggs in spike flowers. The eggs are white or light yellow, 0.5 mm in size. On average, there can be 6–8 larvae at the site of a grain.
The hatched lemon-colored larvae feed on the ovary and anthers of wheat, and later on young grains. If in the first case the caryopsis is completely destroyed, then in the second case we get caryopsis with wrinkled depressed sides. During the period of wax ripeness, the larvae leave the ear and go into the soil.
Protection measures
Treatments KARATE ZEON (0.1 l/ha, aerial use is allowed), EFORIYA (0.1–0.2 l/ha) at the beginning of adult swarming (ear extension).
Cnephasia pascuana
Damages wheat and barley. Butterflies fly in June – July. The hatched caterpillars overwinter in forest belts. In the spring, with air currents, they are carried to the winter crops. Younger caterpillars live in mines, gnawing out the parenchyma, slightly pulling the leaf towards the central vein. Older caterpillars penetrate the axil of the flag leaf, gnaw the parenchyma and cause its death and white growth. The last instar caterpillars feed on grain.
Protection measures
Edge treatments of crops adjacent to forest belts with KARATE ZEON EFORIYA preparations (0.1–0.2 l/ha) during the period when larvae emerge from mines
Eurygaster integriceps
An insect that is classified as a particularly dangerous pest. The damage caused by the turtle in the regions of its harmfulness begins to manifest itself already in the “regrowth” - “tillering” phase of winter crops, where the adults fly after wintering.
Adult bugs overwinter in forests and forest belts, under leaf litter. In the spring, when the temperature reaches +15°C, the bugs migrate to winter crops, first colonizing the edges of the fields.
Damage caused by the tortoiseshell bug during this period causes wilting and death of the central leaf, and then the entire plant. Subsequently, depending on the phase of plant development (“tillering” - “flowering”), damage by the harmful bug causes a slowdown in plant growth, underdevelopment of the ear and its whiteness.
The female's fertility is up to 150 eggs. Embryonic development lasts 7–15 days. The larvae emerging from the eggs first stay together and do not feed, but after 2–4 days they spread out and begin to feed. The larvae develop in 30–40 days, molting 4 times.
Damage to wheat in the “flowering” - “full waxy ripeness” phase, usually caused by larvae, can cause partial whiteness and drying out of the grain. Damage after the “full waxy ripeness” phase, when the grain acquires a hard consistency, leads to a deterioration in baking qualities, a decrease in germination and gluten content.
Protection measures
It is recommended to use the preparations AKTARA (0.06–0.08 kg/ha), KARATE ZEON EFORIYA (0.1–0.2 l/ha).
Depending on weather conditions, the emergence of the bug after overwintering may be delayed, as well as the laying of eggs and the development of larvae. In most cases, one treatment against larvae and adults is not enough and 2–3 treatments are necessary to obtain high-quality grain.
Taking into account the properties of the preparations and the biological characteristics of the pest, it is recommended to use the insecticide AKTARA against overwintered adults in the “regrowth” - “tillering” phase (EPV on winter wheat 1–2 specimens/m², on spring wheat - 0.3–1.5 specimens/m² ) and against larvae in the “flowering” - “milk ripeness” phase (EPV - 2 copies/m²). These are the most optimal phases of using the insecticide AKTARA, when the drug penetrates well into plant tissue, which provides effective and long-lasting protection when used in the “regrowth” - “tillering” phase, not only from the pest bug, but also from grain flies, and in the “ flowering" - "milky ripeness" reduces the number of aphids and thrips.
Treatment with the KARATE ZEON insecticide is recommended against larvae starting from the milky ripeness phase (EPV on strong and valuable wheat 1–2 copies/m², ordinary wheat - 2 copies/m²). The drug has a rapid initial and long-lasting activity, which prevents a decrease in the quality of wheat grain, caused not only by the pest bug, but also by aphids, thrips, and corn beetles.
The optimal processing time is the predominance of larvae of the 1st and 2nd instars, and the 3rd instar is represented by no more than 15-30%, with every 3-4 days of delay - a decrease in efficiency by 20%.
Schizaphis graminum Rond.
Damages all cereals. Fertilized eggs overwinter on cereal leaves. The female's fertility is up to 10 eggs. In the spring, the eggs hatch into larvae, which, after the fourth molt, turn into wingless female founders that reproduce parthenogenetically. The larval phase in summer lasts from 4 to 12 days. Aphids produce 10 or more generations during the growing season.
Protection measures
Treatments of crops with KARATE ZEON (0.15 l/ha, aerial use is allowed), EFORIYA (0.1–0.2 l/ha) are carried out at a population of 10 specimens. on the ear and populating 50% of the plants.
Cephus pygmaeus L.
The larva, which has completed its development, overwinters in the stubble at the base of the stem. In spring, the larva pupates in a cocoon. At the end of May - beginning of June, adult sawflies fly out. The fertility of one female is 35–40 eggs. The larva that emerges from the egg feeds on the tissues of the inner wall of the stem. When the grain reaches waxy ripeness, the sawfly larva descends to the very bottom of the stem, usually below the soil surface. Then the larva makes a circular cut inside the straw, through which the stem easily breaks under the influence of the wind. Sawfly larvae damage winter wheat and rye the most, less so spring wheat and barley, and even less damage oats.
Protection measures
Stubble peeling and deep plowing, which destroy a significant part of the sawfly larvae.
Phorbia fumigata
Puparia overwinter in the soil. Pupation is completed in early spring, and the wheat fly emerges 7–14 days earlier than the Swedish fly. A year lasts 30–45 days. Oviposition begins when spring crops are in the emergence phase. Develops in 2 generations. The development of the first generation occurs on spring wheat, the second - on winter wheat. The fly larva makes a spiral move around the damaged stem, then descends to the shoot growth cone, where it feeds. The central leaf turns yellow and dries out; later, after damage to the tillering node, the entire plant dies.
Protection measures
Deep plowing of stubble. With a high agricultural background, intensive development of lateral stems occurs, and harmfulness is reduced.
Pre-sowing seed treatment with the KRUIZER insecticide (0.8–1.0 l/t) is recommended. During the growing season on spring crops with mass flight of flies - treatment with EFORIYA (0.1-0.2 l/ha) until the 4th leaf appears.
Haplothrips tritici
Damages wheat.
The larvae overwinter in the surface layer of soil at a depth of 10–20 cm. Adult thrips appear before heading of winter crops. Females lay several eggs on the glumes. The female's fertility is 20–30 eggs. The larvae develop within 15–21 days. The larvae feed on filling grain. Dry hot weather is favorable for reproduction.
As a result of damage, the weight and quality of grain decreases; overall yield losses can reach 20%.
Protection measures
Stubble peeling and plowing after wheat harvesting. Treatments with insecticides AKTARA (0.06–0.08 kg/ha), KARATE ZEON (0.15 l/ha, aerial application allowed), EFORIYA (0.1–0.2 l/ha) are carried out when there are more than 10 larvae per ear.
Lema melanopus
Beetles overwinter in the soil. With the onset of warmth, they migrate to cereal crops, preferably oats and barley, where they feed on leaves, eating through longitudinal holes. Females lay eggs on leaves. Fertility - up to 200 eggs. Embryonic development is about 14 days. The larvae skeletonize the leaves. The larval phase lasts about 2 weeks. They pupate in a cocoon in the soil at a depth of 2–3 cm. After 2 weeks, the beetles emerge from the cocoon and fly to the stubble crops of corn, sudanese, and sorghum, where they feed. In outbreaks, the number of beetles can reach 300 individuals per 1 m².
Protection measures
Immediate post-harvest peeling and plowing. Treatment of crops with the preparations AKTARA (0.06–0.08 kg/ha), KARATE ZEON (0.15 l/ha, air use allowed), EFORIYA (0.1–0.2 l/ha) should begin when the economic threshold is reached harmfulness - 0.6 larvae per stem, but not earlier than 50% of the larvae hatch.
Zabrus tenebrioides
The larvae cause damage to winter crops. The beetles colonize crops during the filling phase and feed on soft wheat grains at night. After harvesting grain at a temperature of 28–34°C and drought, the beetles take refuge under stacks, on the remains of straw, and in forest belts. The duration of dormancy depends on soil moisture. From the second half of August - in September-October, females lay eggs in the soil to a depth of 5–15 cm. There are 10–30 eggs in a clutch. The average fecundity of a female when feeding on winter wheat grain is up to 120–270 eggs, without feeding on grain - about 30. Embryonic development at an average daily temperature of 23–25°C lasts 9–12 days, and at 12–14°C - 20–25 days. At night, the larvae come to the surface and feed on the leaves of winter crops. During the day, the larvae pull some of the leaves into the burrows and destroy them. With the onset of cold weather down to 0–5°C, the larvae stop feeding and go to a depth of 30–40 cm, where they overwinter, and in the spring they continue to feed. The intensity of damage is related to the age of the larvae and the phase of plant development. At the beginning of tillering, 15 larvae/m² of the first instar cause the death of 9% of plants, the second - 38%, and the third - 85%. They pupate in the soil at a depth of 10–18 cm.
Protection measures
Fast harvesting, reduction of grain losses, stubble peeling and plowing with skimmers. Timely destruction of carrion seedlings where beetles can accumulate. The most appropriate treatment of seeds is the insecticidal protectant KRUIZER (0.5 l/t). Treatments with insecticides AKTARA (0.1 kg/ha) and EFORIYA (0.2–0.3 l/ha) are carried out against younger larvae during the period of their active feeding.
Anisoplia austriaca
Larvae of different ages overwinter in the soil. The duration of the larval stage is 22 months. Larvae of the first year of life overwinter at a depth of 30–55 cm, of the second year - at 20–45 cm. After a secondary wintering, they pupate in the second half of May, the pupal phase lasts 13–21 days. The beetles emerge from the soil in mid-June. After mating, the females go into the soil to lay eggs. The female's fertility is up to 50 eggs. In wet years, females lay eggs in the soil in the same field where they fed; in dry years, in tilled fields. The egg develops in 20–30 days. The larvae feed on humus and plant roots. In large numbers, they can cause thinning of cereal and row crops. The main damage to grain crops is caused by beetles. They feed on ripening grains and also push them out of the ears onto the ground. One beetle destroys the grain of approximately 9–10 ears.
Protection measures
Treatments are carried out with KARATE ZEON (0.2 l/ha, aerial use is allowed), EFORIYA (0.1–0.2 l/ha), when the number of beetles is more than 3 individuals/m².
Oscinella frit
The last instar larva overwinters inside the plant stem. The summer of flies in the spring coincides with the beginning of flowering of early varieties of apple trees. An adult fly needs additional nectar nutrition. When winter seedlings appear in autumn and spring crops in spring, female flies lay eggs on plants with 2–3 developed leaves, placing them mainly behind the coleoptile. The duration of embryonic development at a temperature of 22°C is 4–8 days. The larvae emerging from the egg penetrate the stem of the main or lateral shoots of the plant, to the embryonic primordium of the ear, on which they feed. A plant damaged in the early phase of germination dies. The second generation of the Swedish fly emerges during heading and filling of barley. Females lay eggs behind the glumes of barley and oats. The larvae feed on the set grains until they harden. The Swedish fly can produce up to 5 generations. It takes 21–44 days to develop one generation. The first generation develops on spring seedlings, the second on ears of barley and oats, another 1–2 generations on carrion, cereal weeds and corn cobs, and the last on winter seedlings.
Protection measures
Stubble peeling and deep plowing immediately after harvesting. Sowing winter crops at optimal times. Treatment of seeds with the insecticidal preparation KRUIZER (0.8–1.0 l/t) or treatment of foci of Swedish fly infestation with the insecticide EFORIYA (0.1–0.2 l/ha) at the beginning of tillering.
