The insect with whom we want to acquaint you, probably met in your life. This is the Colorado potato beetle, one of the worst enemies of the gardener and gardener. We will analyze his characteristics, origin, livelihoods, as well as means of dealing with the uninvited guest of potato plantations.
Why is the beetle Colorado?
The Colorado potato beetle (Leptinotarsa decemlineata) is an arthropod order of beetles and a family of leaf beetles. Belongs to the genus Leptinotarsa, being its sole representative.
The Latin name (Decemlineata - “ten-lane”, “ten-lined”) was given to the insect because of 10 characteristic black stripes on its wings (5 on each).
But the name more familiar to the Russian inhabitant appeared due to the state of Colorado, where in 1859 a small pest organized a huge pogrom - almost all potato fields were destroyed by a beetle. Another version of the origin of the name is also known. From Mexican (Mexico - the birthplace of this insect) colorado - "color". And this is consistent with the colorful coloring of the insect.
Insect characterization
The Colorado potato beetle is a relatively large insect. The length of the adult representative is 8-12 mm with a width of 7 mm. The shape of the body is circular oval, resembling a convex drop of water. The weight of an adult insect is 140-160 mg.
The body is brilliant. The back is yellow with black stripes, and the abdomen is light orange. The head is relatively wide and round. Black bean-shaped eyes stand out on it. On the head you can also make out a spot in shape resembling an isosceles triangle. 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. On it in regular rows are also spots. There are three pairs of weak legs, "equipped" with special hooks that help move around the stems and leaves of plants.
Elytra hard, orange or slightly yellowish. There are black stripes on them. The wings are webbed and well developed - the animal is capable of quite long flights.
Pseudo-potato beetle
Leptinotarsa juncta is a false Colorado potato beetle that looks similar in appearance to the Colorado potato beetle. Lives in North America, mostly in the United States.
Only a specialist can distinguish it from Colorado - it is all about the orange color of the legs and a slightly different arrangement of the strips on the elytra. But it does about the same harm to agriculture — he likes to feast on nightshade leaves.
Vital activity and nutrition of the beetle
The average lifespan is 1 year. But some individuals adapted to survive the winter season, falling into diapause. Their age can reach up to three years.
Insects survive the winter, burrowing into the soil to a depth of half a meter. They are able to withstand freezing of the substrate to -9 ° C. As soon as the soil warms up to +13 ° C, insects make their way up - to heat, the sun and food. The process of "climbing" can take up to 2 months!
We all know what a Colorado potato beetle looks. What does an insect eat? The diet of all individuals is approximately the same:
- Potato (a favorite treat). Some bugs destroy not only the tops, but the entire plant, reaching the tubers.
- In second place - cultural nightshade. These are shoots and leaves of tomatoes, eggplant, tobacco, sweet pepper.
- Do not disdain beetles and wild nightshade.
Insects are extremely gluttonous. In search of food, very impressive distances can fly. 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 exception is the Far North and desert zones.
Beginning in 1855, beetles systematically caused damage to farmers in Mexico and North America. At the end of the 19th century, the beetle declared itself already in Europe, and by the middle of the last century it had spread throughout almost the 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 bug reached the Urals. And at the beginning of the XXI century - to the Primorsky Territory.
Reproduction and development of the insect
Colorado potato beetles begin to multiply after heat is established, having climbed to the surface. Individuals go through a development cycle characteristic of any insect:
Let's consider these stages in more detail.
Animal eggs
Why is it necessary to cultivate land from the Colorado potato beetle as soon as possible? A female insect can lay up to 1000 eggs in one summer! Masonry can be found on the bottom of the leaves of plants that insects eat.
We describe the stage of development. The egg of a potato beetle has an oblong-oval shape. Length can reach 1.8 mm. Depending on the stage of development (from the 5th to the 7th day), the egg changes its color from lemon, yellow to orange, dark 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. The body length is 2.5 mm. It is completely covered with small hairs. The larva is already feeding on tops, gnawing the flesh of the leaf from the inside.
At the second stage of development, the animal changes its color to bright orange-red. In sizes increase to 4-5 mm. At this stage, it is able to deal with the entire leaf pulp as a whole, leaving only the central vein.
In the third stage, the larva becomes red-yellow, growing to 9 mm. Small hairs on her body disappear. From this age, the insect is already able to move from one plant to another for fresh leaves.
And finally, the last stage of the development of the larva. Here the insect increases in length to 16 mm. It is easy to find an individual by its orange-yellow color. It feeds not only on leaves, but also on shoots.
All four stages of development of the insect takes place on average in three weeks.
We also note that at this stage it is easy to confuse the larvae of the Colorado potato beetle and the harmless ladybug. Their differences are as follows:
- The ladybug larva is more stationary (the feeling that it is tightly attached to the leaf), and the Colorado potato beetle moves freely along the plant.
- The cow has multi-colored spots randomly scattered throughout the body. The potato beetle has the correct 2 rows of black dots concentrated on the sides.
- The 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.
Dolly Colorado Potato Beetle
The Colorado potato beetle carries out the pupal stage already in the thickness of the soil at a depth of about 10 cm. The insect is painted in an orange, pinkish tint. 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 on the surface.
What is it like? The color is still bright orange, the protective cover is soft. Surprisingly, an animal needs only 3-4 hours to find the well-known appearance of an adult beetle! The next 20 days, the young insect eats 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 three years.
Fighting the Colorado potato beetle
Both the farmer and the gardener must definitely deal with this potato pest in order not to leave themselves and their neighbors without a crop. Today, three methods are widely used:
- Chemical treatment.
- The use of folk remedies.
- Fight with the help of natural enemies of the insect.
Let's consider them in more detail.
Chemicals
Many dwell on special drugs from the Colorado potato beetle:
- "Prestige", "Masterpiece". Traditional remedies, known for not being addictive in pests. These are complex spray insecticides suitable for large areas. Processing is carried out at least 20 days before harvest.
- "Dendrobacilin", "Batsikol". New products that are safe for plants, their fruits and tubers - have a biological effect on insects. Drugs should be used strictly according to the instructions, processing from the Colorado potato beetle at least three times with a weekly interval.
Folk ways
The fight against the bug can be effectively carried out as follows:
- 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.
- Beetle is known to find delicious food by smell. Sometimes it is possible to deceive him by planting garlic, onions, beans or beans near solanaceae.
- An excellent remedy against the Colorado potato beetle is to process potato plantings with a decoction or infusion of bitter wormwood, dandelion, celandine, horsetail, and wood ash solution.
- Some gardeners successfully apply mulching of potato rows between spruce and birch sawdust.
- Another "recipe" remedy for the Colorado potato beetle is a solution of vinegar and mustard. In 10 liters of water you need to carefully mix 1 kg of dry mustard and 100 ml of 9% table vinegar. With this composition, process the planting.
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:
- Bedbugs pisus and perillus.
- Dorifophagus flies 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 quite a big disaster for gardeners and farmers. Both its larvae and adult individuals cause great damage to the crop. However, a number of effective and varied methods of pest control are currently being used.