The insect with which we want to acquaint you has probably met you in your life. This is the Colorado potato beetle, one of the worst enemies of the gardener and gardener. We will analyze its characteristics, origin, vital activity, as well as means of combating the uninvited guest of potato plantations.
Why is the Colorado beetle?
Colorado potato beetle (Leptinotarsa decemlineata) is an arthropod of the Coleoptera order and the leaf beetle family. It belongs to the genus Leptinotarsa, being its only representative.
The Latin name (Decemlineata - "ten-striped", "ten-lined") was given to the insect because of the characteristic 10 black stripes on its wings (5 on each).
But the name more familiar to the Russian layman appeared thanks to the state of Colorado, where in 1859 a small pest made a huge pogrom - almost all potato fields were destroyed by a beetle. There is also another version of the origin of the name. From Mexican (Mexico is the birthplace of this insect) colorado -"color". And this is quite consistent with the motley coloring of the insect.
Insect characteristic
The Colorado potato beetle is a relatively large insect. The length of an adult representative is 8-12 mm with a width of 7 mm. The shape of the body is round-oval, resembling a convex drop of water. The weight of an adult insect is 140-160 mg.
The body is shiny. The back is yellow with black stripes, and the abdomen is light orange. The head is relatively broad and rounded. It has black bean-shaped eyes. On the head, you can also see a spot that resembles an isosceles triangle in shape. The antennae (organ of touch) are 11 segments.
The pronotum of the Colorado potato beetle is convex, covered with black spots. I must say, their shape and size depend on the individual. Spots can also make up patterns.
The abdomen is divided into 7 segments. It also has spots in regular rows. There are also three pairs of weak legs, "equipped" with special hooks that help to move along the stems and leaves of plants.
Insect elytra hard, orange or slightly yellowish. They have black stripes. The wings are membranous and well developed - the animal is capable of quite long flights.
False Colorado Potato Beetle
Leptinotarsa juncta is a false Colorado potato beetle similar in appearance to the Colorado beetle. Lives in North America, mostly in the United States.
Only a specialist can distinguish it from the Colorado one - it's all about the orange colorlegs and a slightly different arrangement of stripes on the elytra. But he does about the same harm to agriculture - he likes to eat nightshade tops.
Beetle life and nutrition
Average lifetime is 1 year. But some individuals have adapted to survive the winter season by falling into diapause. They can be up to three years old.
Insects survive the winter by burrowing into the soil to a depth of half a meter. They are able to withstand freezing of the substrate down to -9 °C. As soon as the soil warms up to +13 ° C, insects make their way up - to heat, sun and food. The "ascension" process can take them up to 2 months!
We all know what the Colorado potato beetle looks like. What does an insect eat? The diet of all individuals is approximately the same:
- Potato (favorite delicacy). Some beetles destroy not only the tops, but the entire plant, reaching the tubers.
- In second place - cultural nightshade. These are shoots and leaves of tomatoes, eggplants, tobacco, sweet peppers.
- Beetles do not disdain wild nightshade.
Insects are extremely voracious. In search of food, they can fly very impressive distances. But at the same time, they are ready to easily endure forced hunger for up to 2 months.
Insect Spread
Despite its exotic name, the animal is distributed almost all over the world. The exceptions will be the zones of the Far North and the desert.
Since 1855, beetles have systematically caused damagefarmers in Mexico and North America. At the end of the 19th century, the beetle made itself known already in Europe, and by the middle of the last century it had spread throughout almost its entire central and western part.
In the European half of the USSR, the Colorado invasion was first encountered in the 50s of the XX century. In the 70s, the beetle reached the Urals. And at the beginning of the XXI century - to the Primorsky Territory.
Insect reproduction and development
Colorado beetles begin to breed after the establishment of heat, having climbed to the surface. Individuals go through a developmental cycle characteristic of any insect:
- Egg.
- Chrysalis.
- Maggot.
- Adult.
Let's look at these stages in more detail.
Animal Eggs
Why is it necessary to treat the land from the Colorado potato beetle as soon as possible? A female insect can lay up to 1,000 eggs in one summer! Masonry can be found on the underside of the leaves of plants that are eaten by insects.
Describe the stage of development. The egg of the potato beetle has an oblong-oval shape. The length can reach 1.8mm. Depending on the stage of development (from the 5th to the 7th day), the egg changes its color from lemon, yellow to orange, darkish yellow. After 17 days, the insect larva hatches.
Four stages of larval development
As for the individual of the first stage, it can be recognized by its dark gray color. Body length 2.5 mm. It is completely covered with small hairs. The larva is already feeding on the tops, gnawing the flesh of the leaf.from within.
At the second stage of development, the animal changes its color to a bright orange-red. In size increase to 4-5 mm. At this stage, it is able to deal with the whole leaf pulp, leaving only the central vein.
In the third stage, the larva turns red-yellow, growing up to 9 mm. Small hairs on her body disappear. Starting from this age, the insect is already able to move from one plant to another for fresh leaves.
And finally the last stage of larval development. Here the insect increases in length to 16 mm. The specimen is easily identified by its orange-yellow coloration. It feeds not only on leaves, but also on shoots.
Insects go through all four stages of development in an average of three weeks.
We also note that at this stage it is easy to confuse the larvae of the Colorado potato beetle and a harmless ladybug. Their differences are as follows:
- The ladybug larva is more immobile (feeling like it is tightly attached to the leaf), while the Colorado potato beetle moves freely through the plant.
- A cow has colorful spots randomly scattered all over her body. The potato beetle has the correct 2 rows of black dots, concentrated on the sides.
- Ladybug larva is useful for gardeners and gardeners - it feeds on aphids. But the Colorado potato beetle already at this stage begins to destroy the leaves of nightshade crops.
Colorado potato beetle pupa
The Colorado potato beetle spends its pupal stage already in the thickness of the soil at a depth of about 10 cm. The insect is painted in an orange, pinkish hue. The duration of the development phase depends entirely on weather and climatic conditions. On average it is 10-20 days. At the end of this stage, an adult insect is selected to the surface.
What is it? The color is still bright orange, the protective cover is soft. It is amazing, but 3-4 hours are enough for the animal to acquire the well-known appearance of an adult beetle! For the next 20 days, the young insect feeds intensively. After this period, it is already able to reproduce offspring. If this stage of development caught the beetle in August, then it goes into hibernation, bypassing the breeding stage.
As we have already noted, an amazing feature of the insect is to go into diapause, the duration of which can reach up to three years.
Fight against the Colorado potato beetle
With this potato pest, both the farmer and the gardener must definitely fight comprehensively so as not to leave themselves and their neighbors without a crop. Three methods are widely used today:
- Chemical treatment.
- Using folk remedies.
- Fight with natural insect enemies.
Let's take a closer look at them.
Chemicals
Many stop at special preparations for the Colorado potato beetle:
- "Prestige", "Masterpiece". Traditional remedies that gained fame due to the fact that they are not addictive in pests. These are complex insecticides distributed by spraying, suitable forlarge areas. Processing is carried out at least 20 days before harvest.
- "Dendrobatsilin", "Batsikol". New products that are safe for plants, their fruits and tubers - have a biological effect on insects. The drugs should be used strictly according to the instructions, treating the Colorado potato beetle at least three times with a weekly interval.
Folk ways
The fight against the beetle can be effectively carried out like this:
- Manual processing of each bush: leaves with eggs are removed, larvae and adults are collected. Then everything is destroyed either by crushing, or by placing in a strong saline solution, kerosene.
- The beetle is known to find tasty food by smell. Sometimes it is possible to deceive him by planting garlic, onions, beans or beans next to the nightshade.
- An excellent remedy against the Colorado potato beetle is to treat potato plantings with a decoction or infusion of bitter wormwood, dandelion, celandine, horsetail, a solution of wood ash.
- Some growers have successfully mulched potato row spacings with spruce and birch sawdust.
- Another "recipe" remedy for the Colorado potato beetle - a solution of vinegar and mustard. In 10 liters of water, thoroughly mix 1 kg of dry mustard and 100 ml of 9% table vinegar. Process landings with this composition.
Natural enemies
A good option is to attract animals to your site that feed directly on the Colorado potato beetle and its larvae. These are the following individuals:
- Podiatus and perillus bugs.
- Flies of the genus Doryphophage laying their eggs in beetle larvae. Unfortunately, they are not found in Russian open spaces.
- lacewings, ladybugs, ground beetles.
- Birds - pheasant, guinea fowl.
The Colorado potato beetle is a pretty big problem for gardeners and farmers. Both its larvae and adults cause great damage to the crop. However, a number of effective and diverse pest control methods are currently being used.
