Locusts Are The Most Dangerous Pest In The Plant World. Description Of Control Measures, Photo

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Locusts Are The Most Dangerous Pest In The Plant World. Description Of Control Measures, Photo
Locusts Are The Most Dangerous Pest In The Plant World. Description Of Control Measures, Photo

Video: Locusts Are The Most Dangerous Pest In The Plant World. Description Of Control Measures, Photo

Отличия серверных жестких дисков от десктопных
Video: Swarm Of Locusts DEVOUR Everything In Their Path | Planet Earth | BBC Earth 2023, February
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Of all plant pests, locusts are the most dangerous. If there are corners with unharvested field grasses in the country, you can always find a green filly - a single locust, which will eventually provide the appearance of a winged locust. In 2000, an epiphytotic outbreak of locust breeding left the Volgograd region without a crop (1000-6000 individuals per sq. M of area). In 2010, the pest reached the Urals and some regions of Siberia. Locust flight is terrible. Her flocks can number billions of individuals. During flight, they emit a characteristic sound near a frightening creaky, and in the distance reminiscent of a pre-storm thunder. After the locust, there is bare ground.

Migratory locust, or Asian locust (Locusta migratoria)
Migratory locust, or Asian locust (Locusta migratoria)

Locust spread

The family of true locusts (Acrididae) includes up to 10,000 species, of which about 400 are common in the European-Asian range, including the Russian Federation (Central Asia, Kazakhstan, south of Western Siberia, the Caucasus, south of the European part). The most widespread and harmful locust for the Russian Federation is the Asian or migratory locust (Locusta migratoria). There are two life phases: solitary and herd. The gregarious form of the locust is harmful. Representatives of the solitary phase occupy mainly the northern regions of the marked range, while gregarious ones occupy southern and warm Asian ones.

Locust severity level

An omnivorous pest with the highest feeding activity in the early morning and evening hours, when there is no heat peak. One individual eats up to 500 g of plants with different densities of vegetative and generative organs (leaves, flowers, young branches, stems, fruits). Covers distances up to 50 km per day. With a gap of 10-15 years, the locusts form huge swarms (bands) of adults, from the combined aggregations of larvae. During the period of mass reproduction, they are able to simultaneously occupy up to 2000 hectares and fly, feeding on the way, up to 300, and with a favorable wind even up to 1000 km, leaving bare ground with separately protruding remnants of woody shoots and plant stems.

Under natural conditions, over time, the number of pests decreases (the onset of cold, hunger, the work of natural entomophages). The number of diseases affecting the pest in different phases of development, starting from the egg phase, increases in the bands. Recovery lasts 10-15 years and then a massive flight is repeated.

Morphological description of locust

In appearance, locusts resemble grasshoppers and crickets. A visible distinguishing feature is the length of the antennae (in locusts they are much shorter) and the presence of a curved sharp keel on the pronotum, powerful jaws. The forewings are dense with brownish-brownish spots, the hind wings are delicate transparent with a yellowish sometimes greenish tint.

Locust development cycle

The lifespan of an adult is from 8 months to 2 years. The locust lives and develops in two phases / stages - solitary and gregarious.

Single phase

The solitary locust is distinguished by the overall size of its forms, has a green color, for which it received the name "green filly". She leads an inactive lifestyle and practically does no harm. A solitary life phase for the locust is necessary to maintain the population. During this period, the females lay eggs intensively. Gradually, the density of larvae increases and reaches a limit, which serves as a signal for the transition to the second stage of development and life.

Herd phase

In the gregarious phase, the female locust begins to lay eggs programmed for the marching foraging program. Researchers suggest that the "bell" is the lack of protein in the diet of adults. Adult locust adults flock, and larvae form dense bands.

Migratory locust, or Asian locust (Locusta migratoria)
Migratory locust, or Asian locust (Locusta migratoria)
Migratory locust lays eggs
Migratory locust lays eggs

Locust breeding

Locusts usually die at the end of October with the onset of persistent cold. Before the onset of cold weather, the female lays eggs, forming winter apartments in the upper 10 cm layer of soil, which are called egg capsules. During the egg-laying period, the female locust secretes a frothy liquid from the gonads, which quickly hardens, separating the eggs from the surrounding soil. During the laying of eggs, the female forms several capsules (egg-pods) with a lid, inside which she places 50-100 eggs, up to 300 or more in total. During winter diapause, the eggs acquire cold resistance and do not freeze even in severe winters. With the onset of warmth, the winter pause ends and in the spring, when the soil warms up sufficiently, a white larva appears from the egg in the upper layer. On the soil surface, after a few hours, it darkens, acquires an imago-like appearance (without wings) and begins to feed.Within 1.0-1.5 months, the larva passes 5 instars and turns into an adult locust. Another month of increased feeding, and after mating, the female locust begins to lay eggs. During the warm period, each female forms 1-3 generations.

By way of life, the locust is a gregarious species. In years with a sufficient amount of food, a moderately humid climate and average temperatures, solitary individuals do not cause huge harm. But it is necessary to take into account the cyclical nature of development and the transition from a solitary lifestyle to a gregarious one. It appears after about 4 years. During this period, especially when coinciding with the hot, dry summer period for 2 to 3 years, the locust multiplies vigorously, forming huge accumulations of larvae in a small area (bands). Outbreaks of outbreaks that coincide with weather conditions can last for several years, gradually fading out and returning to a solitary life form. The interval between epiphytoties is on average 10-12 years.

Individuals of the gregarious form, trying to maintain the protein and water balance of their body, are forced to feed without interruption (otherwise they will die from their lack in the body). Moving in search of fresh food, they pass, as already noted, from 50 to 300 km per day. One individual is able to eat 200-500 g of green mass of plants and similar neighbors in the band. Protein deficiency turns the locust into a predator, and the flock is conditionally divided into 2 groups. One runs away from relatives, the other catches up with them and eats them up, and both "along the road of life" are supported by plants rich in carbohydrates. The natural gradual decrease in the number of the pest is caused by outbreaks of diseases in flocks of locusts with their high density, the defeat of eggs in egg-pods by various diseases, natural enemies of the locust (predatory insects, birds and other representatives of the fauna).

Consequently, the most vulnerable spot in locust development is the increased density of egg deposition and larval hatching (per unit area). Locust swarms begin their flights at an increased density of pests. This means that it is necessary to initially destroy the clutches of eggs and "islands" of larvae, plowing up the land to reduce the density of pests. In summer cottages, the main role of population reduction is based on comprehensive measures to combat the pest: agrotechnical measures + chemical treatment of soil and plants.

Locust control methods

Given the speed of movement, voracity and the complete destruction of green plants along the path of a swarm of locusts, chemical control measures are used to destroy it, especially over large areas.

At the dacha or in the local area, locust control is mainly prophylactic and begins with agrotechnical measures, the thoroughness and timely implementation of which helps to significantly reduce the number of pests and prevent epiphytotic harm to the green world of plants.

Migratory locust, or Asian locust (Locusta migratoria)
Migratory locust, or Asian locust (Locusta migratoria)

Agrotechnical measures

In areas prone to locust attack, late digging of the summer cottage or house area is necessary, in which the egg-pods with the locust eggs are destroyed.

For early autumn digging, deep spring harrowing is recommended. This technique damages the egg capsules laid after early digging of the site.

In alternative agriculture, unused areas need to be tinned to prevent egg-laying and egg-laying by female locusts.

Chemical control measures

All chemical treatments are best done in the morning. When working, observe personal safety measures, work in an appropriate suit, respirator, glasses, gloves. When working with chemicals, it is necessary to strictly follow the guidelines for the cultivation and use of pesticides.

With a large accumulation of locust larvae in certain areas, it is treated with Decis-extra, Karate, Konfidor, Image, the validity of which lasts up to 30 days. Can be treated with all drugs that are used to combat the Colorado potato beetle.

Systemic insecticide Clotiamet-VDG provides plant protection against locust for up to 3 weeks. After 2 hours, all pests die, the number of live hatched larvae is noticeably reduced. The drug can be used in a tank mix with fertilizers and growth stimulants with a mandatory check for compatibility.

Insecticide Gladiator-EC well removes larvae and adult locusts. Used in the early hours, when adults are in a daze. Doses of the drug vary with the age of the locust.

Damilin is an insecticide with a unique effect on the growth of the pest and the formation of chitin in the body of the larva during molting. As a result, the larvae die before reaching the age of an adult pest. Valid up to 40 days. The drug is low-toxic to humans and warm-blooded animals, rapidly decomposes in water and soil.

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