What does the hero of crosswords look like - the bread bug Kuzka
Content:
Bread beetle looks very similar to May. It causes great harm to the crops of winter and spring cereals. With tenacious paws, he masterfully fingers spikelets and flies to a new object in search of food. In terms of damage, it is not inferior to the malicious pest of the Colorado potato beetle. The only difference is that the latter is an affliction for potatoes, and the bread bug for cereals.
What does a bread bug look like?
The insect is part of the family of lamellar beetles. The habitat is widespread in the European part of Russia, especially in the Volga region, the steppe regions of Ukraine, the Caucasus, and Asia.
Interesting! The pest has been known since ancient times. In Russia, the bread bug was called Kuzka. According to one hypothesis, the beetle larva became the “progenitor” of the notorious expression “Kuzkina mother”. She leads a secretive lifestyle in order to get her, that is, to “show Kuzkin mother”, she will have to try hard and dig the earth deep.
Appearance
The bug Kuzka is presented in the photo. The resemblance to the May bug, which manifests itself in the color and shape of the body, immediately catches the eye. However, there are a number of signs by which an adult bread bug can be recognized:
- stocky black body from 10 to 16 mm long;
- the color of the head and pronotum is dark with a bottle of metallic luster and strokes;
- leathery elytra of saturated brown tones, often yellow-red, closer to the edges of a darker brown color;
- frequent short spikes are visible on the lateral edges of the wings;
- almost all individuals on the elytra have a recognizable dark spot, but beetles are sometimes found without it;
- elongated head shield;
- powerful jaws equipped with sharp teeth;
- well developed legs and abdomen densely covered with gray hairs.
On a note! In beetles, sexual dimorphism is clearly manifested. Females are more rounded in shape. The male is characterized by a hook-shaped claw located on the front paw.
Oval eggs are covered with a dense leathery shell. Color is white opaque. The length does not exceed 2 mm.
The larvae are curved in shape, resembling the letter “C”. In length they grow up to 36 mm. The caterpillar is white with a yellow-brown head. On the last segment of the trunk, there is a recess on the outside, and 2 longitudinal rows of spines are located on the inside.
Pupa of brown color, without visible processes. Length varies between 14-17 mm.
Features of breeding bread beetles
The life cycle of the Kuzka bread beetle from an egg to dying is about 2 years. Most of them, about 22-24 months, he spends in the larval stage. Having completed pupation, young beetles leave the soil in June. Immediately begins their active years, which lasts until August. In different regions, slight deviations of the summer schedule are recorded.
Interesting! You can notice bread bugs only in the daytime. They are especially active in clear sunny weather. They spend the night hiding under clods of earth or in cracks in the soil.Beetle Kuzka is not distinguished by early morning awakening and flies out of shelters after 9 hours.
During the summer, the Kuzka bread bugs emit a characteristic buzz. The peak of “gluttony” of insects is noted after 15-00, when the heat begins to decline. On cold, cool days, beetles do not rise from the soil.
2 weeks after departure, the bread beetles begin mating. Usually the process takes place on fodder plants. After that, the female proceeds to egg laying. It is noteworthy that in the population the number of females is twice the number of males.
To lay offspring, the female digs into the soil to a depth of 15 cm in the same place where the feeding took place. The female lays eggs in a few tricks. Each clutch contains 30-40 embryos. If the soil is loose and soft, the female makes 2-3 masonry, after which it dies in the soil. The maximum fecundity of each female bread beetle does not exceed 100 eggs.
The development phases of the Kuzka beetle
Embryo development lasts 3 weeks. Excess moisture, as well as its lack, can destroy delicate eggs. Newborn larvae from adult caterpillars differ in length, dazzling white color and head capsule size. As you grow older, the head becomes darker in color. The first molt occurs at the end of summer. The larva undergoes two more molt next year.
On a note! Larvae inhabit the soil. Depth depends on humidity, ambient temperature. In the spring and autumn, they can be found almost in the surface layer at a depth of 1-5 cm. With the onset of drought and frost, the larvae of the Kuzka bread beetle go 25-30 cm deep. In cold regions, during the winter period they can bury to a depth of 80 cm.
Young caterpillars feed on small roots, rotting plant debris that can be found in the soil. Larvae hibernate twice. The winter period is carried out in a state of numbness. The optimum temperature for diapause of bread beetles is within 0 ° С.
Larvae that have successfully wintered 2 winters in May begin to pupate. The process takes place in the soil at a depth of 15 cm. The larva prepares itself an oval recess. Like eggs, pupae are very susceptible to changes in humidity and light.
After 2-3 weeks, young beetles appear from the pupae. In the early days, their elytra are soft, and the cover has not yet acquired the necessary strength. Individuals spend several days in the ground. After adaptation, darkening of the elytra, young beetles are selected from the soil.
Harm caused by bread bugs
The beetle is a pest of cereals. Damage is caused by both adult larvae that damage the root system of seedlings, plants, and adult beetles:
- in the spring, the larvae are in the surface moistened soil layer and are able to eat up spring crops, seedlings of sunflower, beets;
- in autumn, the larvae switch to winter shoots.
On a note! Larvae of the second year of life pose a serious threat to young seedlings of spring wheat. With 45-60 individuals per 1 m² of area, seedling thinning reaches 70%.
No less harm is caused by adult bugs Kuzka. Fields with spring wheat suffer most from them than winter crops, since the time spent on them is much longer. According to experts, on winter cereal, Kuzka destroys 1.1 g, and on spring cereal it can damage 2.3 g.
In revaluation for grains, each bread bug destroys about 180 pieces, which is 10 ears. According to some reports, the harmfulness reaches 400 grains. Moreover, the wrecking of the insect is comparable to the well-known expression: "I will not eat, I bite it like that." Kuzka not only eats the grains, but simply knocks them with his paws.
Causes of Mass Reproduction of Pests
A few centuries ago, wheatgrass was the main food source for bread bugs. The development of agriculture has led insects to switch to a more delicious source of nutrition - cereals. This greatly influenced the improvement of their living conditions.In addition, non-compliance with crop rotation, insufficient cultivation of fields are only in favor of the development of the population.
Favorable weather conditions also contribute to the increase in the number of bread beetles:
- warm winters do not contribute to the destruction of wintering individuals;
- the abundance of rainfall during embryonic development and hatching larvae favorably affects the development of insects.
How to deal with a bread bug
The Kuzka beetle has natural enemies that control the number of pests. These include rooks, jackdaws, crows, sparrows, starlings, storks, predatory species of flies, wasps.
Interesting! Previously, the peasants noticed the fact that the Kuzka bread bugs operate mainly along the edges of the field and never climb inside. In connection with these, the cheapest crops were planted around the perimeter of the bread plantation in order to divert the attention of pests.
In modern agriculture, the following measures are taken to combat the bread bug Kuzka:
- compliance with cyclic crop rotation;
- early autumn plowing - late autumn digging is absolutely useless with respect to larvae, as they go to great depths;
- row spacing in June;
- harvesting cereals as early as possible;
- insecticides against beetles have been used for the past 10 years, organophosphorus compounds have proven themselves well. The use of "Metaphos" or "Chlorophos" ensures the death of 90% of beetles.
Often, chemical treatment against bread bugs can also destroy the bug pest larvae.