Bread beetle, or as it is called, "Kuzka" is a pest of barley, wheat and other cereals.These insects belong to the family of scarab, Coleoptera.Pests known to many people in Russia and Ukraine.
Description insect
Kuzka beetles - pests are different green, almost blue tinge legs and body.Their elytra dark brown color, they have longitudinal grooves.Around the shield has a dark spot (in females).The size of this insect is 13-16 mm.Their eggs are spherical, white color, diameter about 2 mm.Larvae length - 35 mm.It is characterized by white, and her head is yellow-brown hue.Then there is the brown doll up to 17 mm.The beetles begin an active life in June and July.At this time, they live on the ears.Females begin to lay eggs in July.They omit them into the soil to a depth of 20 centimeters.Over time the female is able to bring about 50 eggs.Beetle Kuzka all stages of the development taking place in the soil.Depending on the temperature of the eggs may be "ripe" for a time from 2 weeks to a month.The period of larval development lasts 23 months, during which time they are going through two winters at a depth of 80 centimeters.By May of the second year of the larva climbs up and turns into a chrysalis to a depth of 15 cm. The duration of pupa lasts 10 to 20 days.In late May - early June, the young beetle flies already Kuzka.
Distribution insect
homeland of this beetle are European steppe.It is spread in Moldova, in some parts of Western Europe, in the European part of Russia and in the steppe regions of Ukraine.In addition, he lives in the steppes of Turkey, Kazakhstan, the Urals, Altai, the North Iran.Beetle inflicts substantial harm in the south of Russia and in the black soil regions of Ukraine.He also greatly harm in Azerbaijan and some regions of Kazakhstan.
ecological characteristics
Kuzka Beetle is a heat-loving creature.Young animals begin to leave the ground only if the air is warmed to a temperature not lower than 17 degrees.At a temperature of + 200C females begin to ripen eggs for laying.These insects are very active.They feed only during daylight hours, especially if the weather is hot.At nightfall, they fall to the ground.If you hold bad, cool weather, they did not rise from the ground.Therefore, only in the hot and dry summer grain beetles begins at the active reproduction, while the period usually falls at the time of earing crops.If the summer was cold and rainy, the number of insect decreases dramatically, vtorogodnie larvae may die.Moreover, in times of drought they try to go deep into the soil.Adults choose cereals and feed them.They prefer spring forms of rye, barley and wheat.These insects like not only cultivated species but also wild.So they choose wheat grass, wheat grass, timothy, brome and others.These grain pests mainly "occupy" the edge of grain fields.Kuzka beetle eats the flesh of unripe crops and mature grain takes off from the stems.
In the first year of development of the larvae consume humus and thin roots of various plants.The following year, the lives of their main diet are the roots of sugar beet and cereals.Birds like to eat like the imago, and their larvae.The main enemies Kuzka - a predatory ground beetles, asilidae and chips.
Damage to beetles
harms not only the adult bread beetle, and its larvae.Each year, one individual consumes about 8 grams of grain, but even more, he just knocks out ears.Thus, it can destroy up to 10 spikelets.The larvae damage the other way.They feed on plant seedlings and roots of grasses, which in turn leads to a rare seedlings.It is believed that this type of beetle harms with the number more than three units per quarter.km.Thus, if the seeding density per km2 - 250 kolosonosnyh stems, beetles and more than 10 pieces, the yield loss reaches 50%.If you take a few years, favorable to the spread of the beetle, the field margins on the same square.km can count up to a hundred individuals.
Measures to protect crops from beetle
Between the end of spring and early summer is necessary to carry out the cultivation and processing of rows.Such an event leads to massive destruction of pupae of the beetles.Also in the early wax ripeness necessary to conduct separate fast cleaning, picking up the rolls.These actions also reduce the number of damaged grains.In addition to the next year of planting grain beetle Kuzka not crawled out of the ground, it is necessary to hold early post-harvest plowing and shallow plowing perform.These actions lead to the death of eggs and larvae before they delve into the lower layers of soil.
If the number of bugs exceeds the threshold of damage (more than 3 pieces at 1 m.), On wheat during milk ripeness necessary to organize spraying crops with insecticides, CE (l / ha) sumitionom - 0.8 - 1 or decis Extra - 005.In this last spray should be carried out not later than 20 days before harvest.
