Many people who plant potatoes know about a cunning worm that can gnaw winding wormholes in a potato tuber. It is called a wireworm, and the beetle that grows is a click beetle.
This summer, the majority of private potato plantings, having experienced unprecedented heat, also suffered greatly from wireworms. Cleaning and consuming the root vegetable after the wormholes that this worm leaves behind becomes quite problematic and unpleasant. Therefore, many of our site readers are probably wondering how to get rid of wireworm? We will try to answer, since there is still time to prepare for the decisive “battle” with the wireworm.
Click beetle feeds on leaves and stems
You need to know the enemy by sight
The habitat of the click beetle, one of the most common potato pests in our country, is very extensive: from the southern black earth regions right up to the Arctic Circle. The beetle itself is harmless to humans. It feeds mainly on the leaves of cereal plants. Much more trouble with the harvest is caused by its larvae, wireworms. The name of the worm is due to the similarity of its elongated, hard, yellow-brown body to a piece of wire.
In the first year of their development, small light yellowish larvae grow from the clutch; in the next two years, the larvae only increase in size, and in the 4th year, in the summer, they turn into pupae, which after half a month are already formed into click beetles. On the fifth day of May, young female beetles already begin to lay their clutches of eggs.
What does a click beetle larva like to eat?
Click beetle larvae They are practically omnivores and are able to move in all directions in search of food. Their oral apparatus allows you to easily bite into even the thickest stems and roots of plants. It is harmful to almost all vegetable crops, such as beets, carrots, potatoes and onions. Does not disdain cereal seeds, especially wheat. Likes to feed on wheatgrass rhizomes. To a lesser extent it damages flax, peas, and buckwheat. Wireworms love moist, weedy soil that is moderately acidic.
Where do click beetle larvae come from?
The formation cycle of a click beetle is several years. Depending on the species, female beetles lay up to several hundred eggs in the top layer of soil. About a month later, the eggs hatch into larvae that grow for several years and then pupate in the soil. During the period of intensive plant vegetation, the bulk of the worms are located at a depth of 10-12 cm.
Methods to combat wireworms
Potato growers claim that to rid the soil of wireworms currently not yet available for gardeners chemicals. Therefore, you should use other, proven different people ways:
- Digging up soil in late autumn period time (before the first frost).
- It is necessary to remove weeds from the garden, especially wheatgrass and fireweed.
- Reduce soil acidity. For these purposes, coal ash, mineral fertilizers, and slaked lime are added to the soil.
- From time to time the soil should be loosened. For potatoes, it is most convenient to loosen between rows.
- Application to the soil mineral fertilizers(ammonium sulfate, ammonia water)
- When digging up the soil, it is imperative to destroy worms, pupae and the beetles themselves.
- Liming the soil helps a lot in some areas. To do this, when digging, you need to add lime, egg shells, chalk, etc.
- Make so-called baits (some of them are described below).
- Increase the content of nitrogen compounds in the soil. For example, legumes need to be planted in an infected area.
- In the spring, when planting potatoes, the holes, and when planting with root crops, the grooves should be shed with a weak pink solution of potassium permanganate from a watering can or spray bottle at the rate of 5 grams per 10 liters of water, 0.5 liters of water per hole.
- One of the old time-tested ancestral methods is to add dry onion peels to each tuber when planting.
- In the fall, lay straw or manure in heaps throughout the area. When the first frosts arrive, the piles must be burned.
- When planting potatoes, add 5% diazinon (30 grams per 10 sq.m.) to the holes.
Radical methods of combating click beetles and their larvae
himself effective method wireworm control currently there is no such thing for ordinary summer residents. It is necessary to carry out full-scale integrated soil treatment.
Here is one type of complex agrotechnical measures to remove wireworms from your site.
When planting, add “Bulba” (Biomaster) fertilizer for potatoes to the nest. Along with potatoes, it is necessary to plant beans or broad beans (every 3-4 bushes). You can plant marigolds or calendula nearby. We plant the potatoes in shallow grooves made in advance with a hoe. Make the distance between the rows larger, approximately at a distance of 1 meter; you need to plant in a row at a distance of 25-30 centimeters from each other. Hill up 3 times during the summer.
Also for destruction of wireworm chemical industry produces the drug bazudine.
Using wireworm baits
1) Getting rid of the click beetle Bait crops of oats, corn or barley may help. Soak the seeds of these crops for 2 hours in a solution of complex action insecticides. They should be sown two weeks before sowing potatoes or can be sown together in row spacing. The plants produce poisoned seedlings, which the worms eat within one week.
2) The hard way. You need a lot of cans. We take half-liter glass jars and put pieces of chopped raw potatoes and bury it on the site in shady place to the neck. About 10 pieces are needed for one hundred square meters. Every two days in a row we collect beetles, replacing spoiled bait as necessary. We use it all summer. This method is well suited for exterminating adult click beetles.
3) Plant pieces of chopped raw potatoes on sharpened sticks about 20 centimeters long and bury them in the potato field at a depth of about ten centimeters. The ends of the sticks should be left protruding above the ground so that they can be easily found later. Every two days, the baits should be dug up, the larvae collected from them and buried again.
Head capsule
(top view) is a quadrangle with rounded corners, tapered towards the front.()
sickle-shaped, sometimes straight two-lobed, with small teeth on the inner edge. The inner edge of the mandibles is smooth (family Agrypninae) or with a developed tooth in the middle (family Elaterinae And Athoinae), less often with a pre-apical accessory tooth ( Agriotes). There is a forked top of the jaws ( Aplotarsus) or double jaws ( Sericus). The inner cutting side of the mandibles can be sharp, single-keeled, or flat, double-keeled. - merged into one plate and .Abdominal segments
Prothoracic segment
less only than the cadual one. segment grows strongly to the side and in a number of groups of the species includes prothoracic pleurites (A thoini, Ctenicerini, Cardiophorinae) The prothoracic segment consists of a large presternite, two small episternites and a poststernite. Presternite is represented by a solid chitinized plate ( Athoini) or longitudinal sutures, divided into two large and small rhomboid apical scleretites ( Ctenicerini).Mid- and metathoracic segments
have the same structure and equal length. Unlike the prothoracic segment, they always have two: anterior and posterior. The spiracle is located at the front. - three pairs. All are equally developed and consist of a willow, an ankle, and an ankle ending in a claw. On the legs of different systematic groups, different numbers of spines and hairs are found.Segments
, except for the caudal one, have the same structure and are little distinguishable in size. Exoskeleton of segments of all groups, excluding Cardiophorinae(no clear differentiation), consists of, divided in half by the median line, well-defined pleurites and.Some groups (A thoini, Negastriinae, Ctenicerini) are located on laterotergites, separated by a distinct leathery membrane from.
In species from subfamilies Elateriinae And Oestodinae located along the edges, the pleurites are fused with and separated from them by a faintly visible suture.
Cadual segment
It has great importance for species diagnosis. This is usually the longest segment of the body, cylindrical-conical Elaterini, Agriotini, Adrastin i, spatulate y Melanotin or forked at the apex and with a segmental notch ( Agrypninae, Diminae, Athoinae).Development
Immediately after hatching, wireworms are light, transparent, and yellowish. Length - 1.5-2.2 mm. The development of the larval phase continues from one season to several years. different types.
At unfavorable conditions developmental delay occurs. The number and number of instars of wireworms is not clear. Their number varies in different species from 7 to 14, and in the same species varies depending on development conditions (temperature, humidity, food, etc.). Typically, click beetles molt once a year from birth and twice - in spring and autumn - in subsequent years of development.
Wireworm nutrition
Wireworms feed on liquid fractions. In this regard, they have oral filters formed by hairs and setae of different lengths intersecting in different directions. Everything is covered with them inner surface mandibular apparatus, and the anterior part of the pharynx.
Particles no larger than 3 microns can pass through oral filters. The gluttony of wireworms and the increased harmfulness of species capable of phytophagy is explained by the fact that they are forced to crush and squeeze out several times more food mass than is necessary for normal life.
Based on the nature of damage, wireworms are divided into two large groups:
Environmental factors in the development of wireworms
Humidity
. Click beetle larvae are permanent inhabitants of the soil and are in constant contact with the soil solution. Wireworms removed from the soil quickly die in the absence of contact with moisture. The greater the moisture deficit, the faster the body becomes dehydrated. For example, complete death of the striped click beetle occurs even at 98% relative air humidity. Species living in steppe habitats are more resistant to lack of moisture in the soil.Attitudes towards humidity vary not only depending on species, but also on geographical populations.
Soil solution concentration
. The larvae are sensitive to the concentration and composition of salts in the soil solution. The main route of penetration of salts into the body of wireworms is the integument. does not take part in this.The covers have a selective sensitivity to salts. The ammonium cation penetrates the fastest and is most toxic, followed by the potassium and sodium cations.
Anions are ranked in descending order of toxicity as follows: Cl -, NO 3 -, PO 4 3-.
Temperature
. Thanks to the ability for vertical migration, they avoid high and destructive heights and low temperatures in the upper layers of the arable horizon.Wireworms are capable of carrying negative temperatures. Thus, species with a wide distribution and distribution in the northern and central regions remain viable at -6...-10°C for 24 hours or more. Southern species tolerate negative temperatures worse.
Geographical distribution
Harmful phase:
Larvae (wireworms) cause the main damage; they feed on underground plant organs: roots, root crops, rhizomes, bulbs. Wireworms gnaw holes in plants, penetrate deep into tubers and root crops, leaving straight passages.
Pesticides
Biological pesticides:
» Diseases and treatment
The wireworm owes its name to its bright brown color with a reddish tint. From a distance the larvae resemble scraps of copper wire.
Click beetles appear in gardens already in April, as soon as the daytime temperature reaches 8-10°. In early May, they lay eggs directly into the soil (under clods, bushes). A new generation of wireworms is born after 15-20 days. During the first year of life, their body reaches 5-7 mm.
What plants are affected by the pest in the country?
The wireworm's gluttony is obvious, no matter what it feeds on. These are grains, melons and vegetable crops, as well as some ornamental plants. Swollen seeds, shoots, young shoots and tender stems can be delicacies. It even reaches the roots of fruit trees.
The larvae show particular interest in the following plants:
- potato;
- corn;
- carrot;
- sunflower;
- salad;
- alfalfa;
- tobacco;
- melon;
- watermelon, etc.
Damaged vegetables not only lose their marketable value, but also become unfit for consumption due to short storage (they quickly rot).
In addition to the harvest, wireworms also pose a danger to humans, which lies in the use chemicals. Toxic substances are deposited not only in the fruits, but also in the soil, which negatively affects subsequent plantings of the new season. This is explained by soil contamination, disruption of its structure and microflora due to the death of earthworms and beneficial microorganisms.
The use of special preparations to protect crops
One of the new developments in agrochemistry is the drug Nemabact, which is obtained by combining two organisms of different species (a predatory nematode and a bacterium). The principle of action of the product is the penetration of the nematode into the wireworm. There it releases a bacterium that destroys the insides of the pest. They, in turn, feed the nematode. The wireworm has no chance of survival.
To combat larvae, you can cultivate the soil:
- Diazinon et al.
Using traditional methods to combat beetles in the garden
It is highly undesirable to use insecticides in the countryside, and products based on biomaterials cost money. And summer residents cannot find time to buy them because of the difficulty of traveling from the outskirts of the city to the center. They come to the rescue traditional methods, which have been tested for effectiveness over the years.
Particularly popular is a recipe that includes a set of plants that are insecticides by nature:
- dandelion (200 g);
- nettle (500 g);
- celandine (100 g);
- coltsfoot (200 g).
Wireworm eating potatoes The components need to be crushed, poured warm water(10 l) and let it brew for 3-4 days. You need to water the beds with the solution 2-3 times with breaks of 1 week.
Preventive methods for the appearance of wireworms on potatoes and potato fields in spring and autumn
Systematic treatments, timely weed control and thorough cleaning of the garden after the harvest leaves no chance for click beetle larvae to survive. As you can see, getting them out is not difficult.
From this little bug your garden plot. Therefore, read and remember! As soon as the sprouts appear different plants, this pest is right there. It is this insect that, due to its rapid reproduction, can very quickly spoil your crop even at the sowing stage.
Adults are only 1–2 centimeters long, a little less than half is occupied by the head. In color, such a beetle is black and dark brown, but can even be brown or purple. At least 5 years must pass from the larva to the transformation into an adult, while females at the beginning of spring are already ready to lay a huge number of eggs - a hundred or more.
The most common conditions for such a pest are: high humidity and the availability of food, then the eggs laid by the females successfully turn into larvae, which at first do not harm the crop. But after a year, the offspring begin to absorb everything that comes their way. Quite strong and flexible, they can gnaw through a root crop and completely render it unusable.
They eat young tubers and swollen buds, damage stems and root system agricultural crops. Starting from the second year of development, the larvae pose the greatest danger. Only in the fourth year do the larvae pupate, and then on your plot of land wait for a new generation of beetles. It is quite difficult to breed them, especially where root crops are constantly grown.
Wireworm - destroying burdocks
The beetle itself and the larvae are very difficult to crush, which is why it is sometimes called the wireworm beetle (for its hard, wire-like body). By the way, there are also false wireworms in nature, for example, which go through the pupation process much faster and turn from larvae into adult beetles. The main difference between a real click beetle and other beetles is that when it turns over from its back, it makes a click, which is why it is called a click beetle.
Be especially careful when checking your beds - the beetle can lay eggs on the weeds. He especially likes to use burdock and wheatgrass for these purposes, which for this reason should be removed as often as possible. It is very convenient for the hatched larvae to immediately move to the ground and begin to look for food in the upper layer of soil.
You can find similar insects in own home– the click beetle feels very at ease in the apartment.
Such beetles leak through various cracks and are often found wet places and reproduce quietly. In this case, if you did not manage to detect the female before she laid eggs, you risk encountering a swarm of larvae after a while. In order to avoid such situations, carefully inspect the premises where you have long-term storage of products, especially potatoes.
Click beetle, also known as wireworm, methods of control
It is believed that there is nothing unnecessary in nature, therefore even such a pest insect can carry out its useful mission. Those who adhere to this point of view believe that such larvae are capable of helping to loosen the soil and can be an indicator of poor or good fertility, thereby signaling problems in the area.
