Food addictions and features of the reproduction of the Swedish fly

There are many diverse flies in the world fauna. According to recent data, there are more than 750 thousand species. Almost all of them somehow harm a person. One of these malicious pests is the Swedish fly, a member of the Chloropidae family. The insect quickly adapts to new climatic conditions and has spread throughout the globe.

A fly is not afraid of either cold or drought, and it can be found everywhere where cereals are cultivated or wild cereals grow. The insect tolerates weekly hunger painlessly and is capable of long-distance migration.

Biological features of the Swedish fly

The first to describe the Swedish fly was Karl Linnaeus, a well-known naturalist and taxonomist. About 30 species of this pest are known, which are distinguished by food addictions.

The Swedish fly cannot boast of a colorful color. It looks inconspicuous and it’s rather difficult to distinguish it from its “brothers”
The most harmful in our latitudes are 2 types:

• Barley fly - the insect is well adapted to drought. For procrastination, it prefers barley stems, which is reflected in the name. Also, this type of Swedish fly affects corn, wheat.
• Oatmeal - taste preferences are displayed in the title. The pest is localized on the crops of oats. The insect tolerates low temperatures well, loves humidity.

For a long period, barley and oat flies were systematized as one species.

How to recognize a swedish fly

For adults, the following features are characteristic:

• the length of the black shiny body is 1.5-2.5 mm;
• ground beetle, yellow legs;
• transparent wings with iridescent overflow;
• on a neat rounded head there is a small proboscis and black antennae;
• the shield is rounded, the back is slightly convex, smooth without any dents or indentations;
• sexual dimorphism is manifested by a different structure of the genitals.

The elongated eggs are cylindrical in milk or caramel color. On the shell, grooves are distinguishable. The tiny size of the egg does not exceed 0.8 mm.

What does the larva look like:

• Hatching larva of a Swedish fly, white, transparent. As they grow older, the color of the body becomes a yellowish, lemon tint.
• The body is cylindrical, divided into thirteen segments. On the back side it is smoothly rounded, tapers to the tail and stands out in an acute form.
• Spines are located on each segment, with the help of which the young individual moves.
• The head almost does not stand out. The oral cavity is represented by sickle-shaped serrated hooks, the color of which changes with the growth of the larva from light brown to black.

Pupation occurs in a brown cylindrical puparia. Two processes are visible at the posterior end, 4 denticles in front.

On a note! Cereal flies are classified as saplings, as the larvae populate the stalks of cereal seedlings.

Features of nutrition and life

The insect spends the winter period in the larval stage, or in the pupal phase, which is reliably protected from frost by puparia. Individuals are found inside shoots of wild cereals and winter crops, in the scavenger. In spring, when the soil layer warms up to a temperature of 12-14 ° C, the larvae come to life, begin to feed intensely and pupate. Young Swedish flies appear on winter wheat and other sprouts of spring crops during tillering.

The years of the first generation of barley and oat flies begins in late April, early May and is determined by geographical location.

On a note! According to observations by farmers, the flight of flies coincides with the beginning of flowering apple trees.

The imago diet consists mainly of flowering plants. The main source of nutrition for them is the nectar of flowers. Swedish flies were seen on the flowers of buckwheat, colza, anise, lupine, vetch, dandelion, yarrow, and valerian officinalis. According to some reports, the insect and aphid, which makes up for protein needs, are not ignored.

Life span Swedish flies depend on meteorological conditions, diet. Without food, they can live no more than 7 days. In ideal laboratory conditions, receiving honey syrup, adults live up to 49 days. In the field, the life expectancy is much shorter and does not exceed 28 days.

It is noteworthy that Swedish flies like to populate well-lit and sun-warmed places with low-growing cereal vegetation.

Breeding

10-30 days after departure from the cocoon, sexually mature individuals begin mating. Females have an instinct for caring for offspring. A female individual scrupulously examines the plant in which oviposition will be carried out, because the development of the larva and the population as a whole largely depends on this. She looks for young shoots, strokes and taps them with a mustache, as if checking for strength and reliability.

Only young stems are suitable for laying eggs. Mostly crops are infected in the second leaf phase. Less commonly, an insect lays offspring on plants with 4 leaves. Stems with more than 5 leaves are not considered barley and oat flies. On winter wheat, Swedish flies can lay an egg in hot weather even after the appearance of the first leaf.

Embryos are placed on the stems or seedling film of the inputs and almost never on the sheet itself. During the period of cereal heading, eggs are located in the spikelet film. Sowing corn Swedish flies attract only in the phase of 1-3 leaves.

On a note! During the season, 5 generations of generations are possible, which, depending on the time of occurrence, populate stems, ears, crop residues, seedlings of winter crops.

Embryonic development lasts from 3 to 8 days. The optimum temperature is 21-22 ° C. With a decrease in temperature, development slows down. Hatching larvae bite the stem and begin to feed intensively. They are not particularly mobile and lead a rather secretive lifestyle. The larvae of Swedish flies undergo 3 maturations, after which they pass to the pupation stage. In summer individuals, the process proceeds in the same plant in which they ate.

Maliciousness and methods

The massive resettlement of Swedish flies on cereals can cause serious damage to the owner of agricultural land. The harmfulness of insects depends on the time of their appearance, the intensity of settlement, the choice of a place on the plant for egg laying, as well as the accompanying weather conditions. Flies of the last generation do the most harm.

The wrecking of Swedish flies is manifested in the following:

• growth retardation of young shoots, shoots, sometimes even their death;
• thickening of the stem, expansion of leaf plates;
• yield reduction;
• if damaged during trumping, the affected stem becomes thinner, bent;
• the appearance of a Swedish fly on corn during the germination period leads to the fact that the larvae eat up the growth cone and seedlings die.

Measures to control barley and oat flies come down to the following measures:

1. Deep plowing of the soil.
2. Selection of resistant varieties of cereals.
3. Sowing work in the optimum early terms.
4. Fertilizing on fields with winter crops.
5. Timely stubble peeling.
6. With mass infection, insecticides are treated.