A bug insect with a beautiful name, the marble bug, is a serious threat to rural farmers. He is the leader in the ranking of pests for the crop industry in our country. Messages about his appearance resembles front-line reports with information about the penetration of the enemy into new regions. The full name of the alien is brown marble bug.
Description and Features
A species typical of a shield bug, similar to insects of its genus. The pear-shaped body of a slightly flattened shape is 11-17 mm long. The color of the developed bug is brownish or gray.
Spots of contrasting shades are scattered on the head and back, for which the characteristic "marble" is fixed in the name of the bug. From a distance, color transitions of different intensities have a copper, sometimes bluish-metallic tint.
The underside of the body is lighter than the top. Gray-black specks are present. Legs are brown, with stripes of white color. Antennae, unlike relatives, are decorated with light strokes. The membranous part of the front wings is marked with dark stripes.
Like other bugs of a large detachment of half-winged, the marble representative of the genus emits an unpleasant smell. A pungent stench conveys the “aromas” of a skunk, a mixture of burnt rubber, cilantro. The appearance of a guest is immediately felt, it is difficult not to feel it. The stink effect is designed to protect the bug from birds of prey, animals.
Among gardeners and gardeners he was nicknamed - a stink bug. The glands that produce the defensive substance are located at the bottom of the chest, on the abdomen. The thermophilic insect feels great when the air is warmed from 15 ° C to 33 ° C. The optimum comfortable environment is a temperature of 20-25 ° C.
Marble bug - a big problem for farmers. The insect destroys crops, fruits, many cultivated plants. The range of gluttonous bugs is constantly expanding. The origin of the malicious shield bug is associated with the region of Southeast Asia (Vietnam, China, Japan), where it was first recorded more than 20 years ago.
Then the bug was brought to America, Europe, distributed in Georgia, Turkey, Abkhazia, penetrated into Russia. It is believed that the immigrant was brought in with supplies of citrus fruits. Massive insect infestations are a serious threat to agricultural regions. Brown-marble bug is in the Unified list of quarantine objects approved by the Eurasian Commission in 2016.
Migrant began to develop the southern regions of Russia 3-4 years ago. The residents of the southern regions of our country experienced a mass pilgrimage to their homes, farm buildings with the advent of autumn 2017.
So, marble bug in Abkhazia destroyed more than half of the tangerine crop. Further, insects were found by residents in the suburbs of Sochi and Novorossiysk.
It turned out that a malicious guest is dangerous not only for the crop, but carries a threat to the person himself. The bug bite is sensitive for people with a weak immune system. The appearance of edema, itching, other symptoms provokes an exacerbation of allergies.
It is difficult to resist invasion because of its insensitivity to insecticides. There are practically no natural enemies for the stink bug, except for the parasitic wasp that lives in China and Japan. The objects of her interest are insect eggs. But since the pest itself is invulnerable, a partial loss of offspring does not affect its distribution across the continents.
The fight against the marble bug only gaining momentum. The ubiquitous resettlement of insects has already caused damage to the US economy by billions of dollars, for which the pest has been nicknamed the American. Scientists are developing tools to destroy the malicious shield bug.
Brown-marble bug is the only representative of its rank in biological systematics. It is not difficult for specialists to identify an insect. But in the areas of its distribution, bugs-bugs are found, similar in size, body shape, color.
You can determine the difference by studying insects using a magnifier with a 5-10-fold increase or by matching, as marble bug in the photo different from the usual summer cottage guards.
Wood bug. In summer, the green bug turns brown for masking in the fallen foliage in the summer. Significant harm to cultivated plants does not bring.
Nezara is green. Vegetable bug of green color with a transparent membrane. By autumn, changes color to bronze. The head and pronotum are sometimes light brown in color.
Berry Shield. The color changes to the color of the surrounding foliage: from a reddish-brown to dark brown. Boca, antennae marked by black and yellow stripes. Threats to the crop does not bear.
Despite the visual similarities, there are significant differences that are important to pay attention to:
- the most important difference of a marble bug is the color of the antennas: the last segment is black with a white base, the penultimate segment is black with a white base and apex. This combination is not found in any other related species;
- the size of most bugs is less than 1 cm - the marble pest is larger.
- the body shape of the “familiar” bugs is more convex than that of an alien.
The combination of the individual coloration of the antennae, size, shape of the clypeus allows us to accurately distinguish the variety of brown-marble bugs.
Lifestyle & Habitat
The vitality of a brown-marble bug is based on the unpretentiousness of the insect to its habitat. The insect is found on the street, in various buildings, cellars, farmsteads, apartment buildings, animal burrows, bird nests. The widespread distribution is not prevented by high humidity, a hot environment.
With the end of the growing season, bedbugs tend to penetrate people’s heated dwellings, find shelter in basements, sheds, where they penetrate through slots, vents. With a decrease in temperature, individuals are especially actively seeking places for wintering. Cases when the owner finds thousands of marble bugs in courtyards are not uncommon.
Insects hibernate under siding, clog into the gaps of the cladding. The wintering phase of the bugs is passive - they do not feed, do not breed during this period. Although insects that enter the premises mistakenly perceive heat for the arrival of spring, they gather around lamps, heat sources.
In addition to aesthetic discomfort, the potential impact of bedbugs on people is alarming. The disgusting smell that insects exude for protection is known. Excreted substance may cause an exacerbation of allergies.
Question, than to poison a marble bug, becomes very relevant. In living quarters, insects are collected manually, chemical-biological agents are used only in open areas.
In the spring, the activity of insects in the search for food, reproduction of offspring awakens. Pest invasions destroy the crops of many fields, destroy fruit trees, which undermines harvesting. In addition to direct harm, a brown-marble bug is a carrier of phytoplasmic diseases that affect many plants.
The damage is especially evident on the fruits of citrus and vegetable crops. Pierced by the trunk of a bug, the skin of the fetus opens the way for the development of necrotic processes. Structural changes begin, spoiling the appearance and taste of the fetus.
Development stops - immature fruits crumble, hazelnut kernels hang on the tree empty, rot affects grape berries. The bug is not spared grain, legumes, ornamental plants.
Get rid of a marble bug can be in many ways. During the development of larvae, the method of shaking off pests into umbrellas or ordinary tissue is used. In places with low numbers, visual inspection and the use of entomological nets are practiced.
Marble bug trap based on the use of pheromone is used in all types of plantings. An increase in the number of insects forces us to constantly look for new means of biological, chemical effects on the dangerous insect shield.
The brown-marble shield is omnivorous. In the spring he is attracted by young shoots of almost all garden crops. The pest at different stages of its development eats the same plants. Larvae and adults pierce the outer tissues of leaves, fruits, and draw out vital juice.
Necrosis forms on the fruit trees in the places where the bugs are affected, the surface of the stems is covered with tubercles, pathological tissue similar to cotton wool is formed in consistency. Fruits, not having time to ripen, decay, crumble ahead of time. Taste qualities of fruits, vegetables, citrus fruits are lost.
In the homeland of the brown-marble bug, in Southeast Asia, experts counted over 300 species of plants that are attacked by harmful insects. Among them, common vegetables are attacked by a bug: tomatoes, peppers, zucchini, cucumbers.
The insect regales on pears, apples, apricots, cherries, peaches, figs, olives, persimmons, corn, barley, wheat.
The pest feeds on legumes: peas, beans, does not spare pome fruits, stone fruits, berries. Forest species fall into the diet of the bug: ash, oak, maple, hazelnuts. Marble bug in Sochi, According to statistics from local farmers, Abkhazia has damaged 32 species of plants. In areas where there are no garden plantings, insects survive, develop on weed feed.
Reproduction and longevity
In a humid subtropical climate, only by November the bugs will subside, when adult individuals go into hibernation. Insects are unusually prolific - three generations of pests appear during the season:
- the first generation develops from May to mid-June;
- the second - from the third decade of June to early August;
- the third - from the first ten days of August to the beginning of October.
Larvae go through five stages of development. It is noteworthy that in the process of growth they change color, which significantly complicated the identification of the insect at one time.
- At the first stage, the larvae are red or bright orange, each length is 2.4 mm.
- In the second stage, the color becomes almost black.
- The third and subsequent stages are marked by brown-white larvae.
The diameter increases to 12 mm. Active reproduction of bedbugs in 2017 broke all records - instead of three clutches per season, scientists recorded six, which became an occasion for discussion of probable biodiversion at the official level.
Representatives of the Rosselkhoznadzor have already noted the facts of the import of harmful viruses into Russia, provoking infection at an unprecedented pace. The challenge ahead is by studying the DNA of a brown-marble bug, developing biological methods to reduce the population. The richness and diversity of the living world is customary to support. But the balance of organisms is no less important for the preservation of prosperous flora and fauna.