A relative of the aphid, the whitefly, is famous for the fact that it copes no worse than its “sister” with eating and damaging many plants, mainly living in closed ground. Let's find out how to fight whiteflies in a greenhouse.
The aleurodidae, better known as the whitefly, got its name due to its appearance: the wings of an adult are white in color, reminiscent of a powdery coating. This small insect (up to 3 mm in length) with 4 wings looks like a very small white moth.
About 1,550 species of whiteflies are known, some of them are dangerous pests, such as citrus, cabbage, and strawberry whiteflies. But in our material we will talk about such a species as the greenhouse whitefly.
This insect loves humidity and warmth, so it prefers to live in greenhouses, greenhouses, closed balconies and apartments. The whitefly reproduces very intensively (about 200 eggs in one cycle), so it is important to notice and destroy the larvae of this pest in time.
Whitefly
In recent years, this small insect has become notorious among both gardeners and lovers of indoor and greenhouse plants. Yes, the whitefly easily penetrates not only into open areas, but also into greenhouses, and even into apartments and houses. This pest gets its name from its small, mealy-colored wings. In general, it is worth noting that the whitefly is not large in size - a maximum of 3 millimeters in length (Photograph). However, anyone who is familiar with this pest will say that it is not so much a matter of size as it is the number and survival rate of the parasite.
Why is whitefly so harmful? The adult insect feeds on the juices of plants, including weeds, but gives preference to tomatoes, cucumbers, peppers, and cabbage. The appearance of a pest is signaled by black, greasy spots on the leaves. If you do nothing, after a while tiny white dots will appear on the underside of the leaves. They indicate that insects have taken a fancy to your greenhouse and are in a hurry to give birth to offspring, which can destroy most of the crop. Soon thousands of larvae will leave their puparia and begin sucking the juices from the plant (Photo). The leaves will be covered with a black coating (larval excrement) in which various fungi will settle. This plaque will block the path of the sun's rays, which means it will stop photosynthesis. It is clear that in such conditions your plants are doomed to death.
This scenario was repeated many times, which gives reason to assert: whiteflies in a greenhouse are much worse than late blight, powdery mildew or the Colorado potato beetle. The worst thing is that today there is no universal remedy that can put an end to this insect once and for all. If you want to protect the harvest in your greenhouse, you will have to take a whole range of measures to combat the pest. Let's first analyze the measures that should be taken to prevent the appearance of whiteflies in a greenhouse.
Traps
This method refers to variants of the mechanical method of exterminating harmful insects. Special traps are purchased, which are bright plates with an adhesive backing. You can make a trap yourself; you will need a strong base, it can be thick yellow cardboard or plywood painted with yellow paint. Anything bright attracts insects. The prepared base must be covered with an adhesive mass, which can be prepared as follows: rosin, castor oil and petroleum jelly must be mixed in a container. Add honey and mix until smooth. Apply the mixture to the base and hang it in the greenhouse, one trap per 10 square meters. meters.
For long-term use, you can use something stronger than a sheet of cardboard as a basis; they can be washed with warm soapy water and used again.
Greenhouse prevention
Work to prevent the appearance of insects in your greenhouse should begin in the fall, immediately after harvesting.
- Remove all plants, dry leaves and stems from the greenhouse - completely empty the greenhouse and cover the soil with cellophane film;
- Using chemicals, disinfect all frames, inter-frame spaces and other parts of the greenhouse. Blow out hard-to-reach places with insecticides; accessible parts can be painted with regular paint;
- After a few days, repeat the chemical treatment of the greenhouse. According to reviews from gardeners, the drug Aktara is best suited for these purposes.
After disinfecting the greenhouse itself, it is necessary to destroy the whitefly in the soil:
- Remove the film and dig up the ground adding slaked lime or ash. The fact is that the whitefly cannot tolerate an alkaline environment;
- Buy several sulfur or tobacco checkers (Pawn-S, Hephaestus) and fumigate the internal space (Photograph). In this case, the greenhouse room must be well insulated. Only after a few days can you open and ventilate the greenhouse.
Important: smoke from bombs kills adults and larvae, but does not cause any harm to whitefly eggs. Therefore, soil disinfection is a mandatory procedure.
- At the first severe frost, it is necessary to freeze the greenhouse, since the whitefly cannot tolerate the cold. It should be borne in mind that insects feel comfortable under the snow, so you need to freeze the room before the first snowfalls or by removing snow from the ground;
- Don’t forget to disinfect the gardening tools you use in the greenhouse – there may be whitefly eggs on them;
- Pay attention to the area around the greenhouse. Remove all weeds, disinfect the soil around the perimeter of the room;
- Sow dill, celery, and parsley at a short distance from the greenhouse. These plants will attract lacewings, ladybugs and some other insects that are the natural enemy of the whitefly and will destroy the pest when it appears;
- In the spring, hang traps around the greenhouse; you can make them yourself from cardboard or polycarbonate, or you can buy them in specialized stores. Particularly popular are glue traps such as Pheromone, Bona Forte, ARGUS;
- When planting seedlings, make sure that there are no whitefly eggs or larvae on them.
Tobacco smoke bomb for greenhouses
Mechanical method
The whitefly is washed away with a strong stream of water. After this, you need to prepare a soap solution, 100 g of laundry soap per 0.6 liters of warm water. Using a sponge, you need to wipe each leaf with this solution, washing off all the larvae. Many gardeners use tar soap to repel insects with a specific smell.
This method is suitable for small greenhouses. For larger areas the effect of this method will be minimal.
Biological methods in the fight against whitefly in greenhouses
The whitefly has many natural enemies that happily feed on it:
- Ladybug. Try to catch these insects and bring them to the greenhouse. The more of them you have living, the less chance there is for whiteflies;
- Predatory bug . Another deadly enemy of the whitefly. You are unlikely to be able to catch him. In exchange, you can buy a small colony of this insect via the Internet;
- Encarzia (Photo). This parasitoid wasp is successfully used in greenhouses against whiteflies. One wasp destroys 60-100 pest larvae in a lifetime. You can order this beneficial insect in online stores; it is sold in boxes of 5,000 pupae each.
Encarzia
How to deal with aleurodida on flowers
Living rooms are just as welcoming for whiteflies as greenhouses and hothouses, so the miniature pest poses a serious danger to indoor flowers as well. The signs of an unwanted guest in your home are still the same:
- shoots stop growing;
- the leaves turn pale and curl;
- the flower fades, and when touched, a white cloud appears above the branches - miniature moths.
To save the plant, it is necessary to thoroughly clean the leaves mechanically (manually) from larvae and plaque (sooty fungus), removing the most affected parts, and treat the plant with a chemical preparation, after first testing the insecticide on one bush (the recommended product is Confidor Extra).
Garden flower plants - petunias, asters, cornflowers, etc. - can suffer from whiteflies. To save them, the same insecticide preparations are used as for vegetables in greenhouses.
Agrochemicals
A variety of chemicals have proven to be most effective in the fight against whiteflies in greenhouses and in open ground. As a rule, they help get rid of the pest, however, when working with insecticides, you should be careful and use personal protective equipment.
Aktara. Perhaps one of the most popular and sought-after insecticides on our market, which is used to combat a wide range of pests. The drug is resistant to changes in weather conditions and can be applied both to plants and to the ground, which is especially important when disinfecting soil in a greenhouse. Aktara belongs to the second class of toxicity, and at the same time it is not addictive in insects and does not accumulate in fruits and soil. It should be borne in mind that this chemical poses a mortal threat to bees and other beneficial insects; it should not be used if there is encarsia in the greenhouse.
Fufanon. This drug is classified as a fumigator, that is, when sprayed, it not only destroys the pest on the plant, but also forms a protective cloud around the leaves and stems. To achieve maximum efficiency, the sprayer must be adjusted to evenly spray very small particles. Fufanon does not leave behind an unpleasant odor; if the instructions for use are followed, it is not dangerous to humans. In the greenhouse, two treatments of plants per season are allowed (tomatoes - 3, cucumbers - 1), the last spraying should be carried out no later than 10 days before eating the fruits.
Fufanon
Aktara
Fitoverm
Rovikurt. A systemic contact insecticide will reliably protect your greenhouse from whitefly invasion. The advantages of the chemical include its low cost, ease of use, effectiveness and moderate toxicity to humans and warm-blooded animals. However, you should know that Rovikurt is deadly for bees - take this circumstance into account if you protect your greenhouse from whiteflies using encarasia. After treating plants with Rovikurt, fruits should not be eaten for the next 20 days. In protected ground, no more than four sprayings per season are allowed.
Fitoverm. Another insecticide for controlling whiteflies in a greenhouse. The drug does not contain substances harmful to humans, it can be used even in houses and apartments. In addition to protective properties, the product also has stimulating functions. The first results appear eight hours after using Fitoverm - insects stop feeding and die in the following days. The disadvantages of the drug include a sharp, unpleasant odor, as well as the fact that it poses a mortal danger to bees and other beneficial insects.
What do we know about greenhouse aleurodide?
There are more than one and a half thousand known species of Aleyrodidae. In Europe, in particular, there are about 20 species, including such “honored” pests as:
- citrus aleurodes (Dialeurodes citri, in Russia found in the Caucasus);
- tobacco (Bemisia tabaci);
- cabbage (Aleurodes brassicae);
- strawberry pest Aleurodes fragariae.
In this article we will look at only one species of whitewing - the greenhouse, or Trialeurodes vaporariorum, which “hunts” cucumbers, tomatoes, eggplants and readily feeds on flower plants.
The ideal habitats for Trialeurodes vaporariorum are warm and humid (greenhouses, greenhouses, residential apartments, closed loggias and balconies). The larvae of this miniature pest must be noticed in time: in favorable conditions, the insect multiplies rapidly, laying about two hundred eggs in each cycle.
The general algorithm for combating greenhouse whitefly is quite simple - the main thing is to detect its presence on plants in time, and then:
- manually remove larvae from leaves (so-called mechanical removal);
- treat plants with protective drugs (chemical insecticides or folk remedies);
- carry out correct preventive measures regularly.
If the invasion is not noticed in time, confrontation will require significant efforts and the use of chemical insecticides.
Advantages and disadvantages of insecticides
Advantages:
- A large selection of drugs on the market at different prices and different mechanisms of action on pests;
- Most chemicals effectively destroy both adult pests and their offspring;
- Some preparations have fumigator properties, that is, they form a protective cloud around the plant.
Flaws:
- Some chemicals can cause serious harm to the natural enemies of whiteflies;
- When using agrochemicals, you must follow safety rules and wear a mask, goggles and gloves;
- Some insecticides are quite expensive.
