Thripses (lat. Thysanoptera), or gallbladder (fringed winged, bellfish) - a detachment of insects of small size, common on all continents. The thrips were first described in 1744 by Karl de Geer, and today more than 6,000 species of these insects are identified, combined in more than one hundred genera.
Pest thrips - description
The length of the black, brown or gray body of thrips reaches from 0.5 to 3 mm, some species are much larger - about 14 mm. The legs of thrips are running, the oral apparatus is asymmetric, piercing-sucking, and the legs are without claws, but equipped with teeth and a vesicular suction device. The abdomen in thrips consists of 11 segments. Along the edges of the wings there is a fringe. The development of thrips goes through five stages: eggs, larvae, pronymphs, nymphs and adults. In thrips larvae, the body is grayish or white-yellow, otherwise they differ from adults only in the absence of wings.
Thrips are polyphages, i.e. omnivores. They are one of the most common pests of agricultural, vegetable, fruit, ornamental and indoor crops. They pose a special danger to plants in enclosed spaces: if thrips are wound up in greenhouses, it is very difficult to get rid of them, you can only restrain their population. It is difficult to detect these pests due to their small size and secretive lifestyle: they can parasitize on one plant for a long time, without spreading to neighboring ones.
Adult individuals and larvae suck juice from the aboveground parts of the plant and infect them with their secretions. First, discolored or yellowish spots, strokes or stripes appear on the bite sites, which gradually merge. As a result of the activity of pests, the plant tissue dies, holes form on the spot, leaves wither and fall, the flowers lose their decorativeness and crumble ahead of time. During mass occupation of the plant with thrips, silver patches appear on its ground organs, the stems are bent, and the flowers are deformed due to the damage of flower buds by pests. On top of that, thrips are carriers of incurable viral diseases.
Thrips - Preventive Treatment
To prevent thrips from settling on your indoor flowers, take preventative measures:
- watch the level of humidity in the room: thrips, like spider mites, like a dry environment, so humidify the air with a fine spray or an electric device;
- regularly inspect plants, especially the underside of the leaves, and if larvae or adult pests are found, immediately arrange the colors of the souls;
- make it a rule to wash indoor plants at least once a month to clean them of dust, pest larvae and adult parasites;
- spread and hang between the plants glue traps - fly tapes or strips of blue or yellow paper with adhesive applied to them. Bait will help you identify the pest and reduce its number;
- Plants purchased or donated to you should be quarantined: keep them away from your flowers for at least 2–3 weeks and monitor their condition.
How to deal with thrips on indoor plants
Thrips on orchids
The fact that thrips settled on the orchid will tell you the appearance of a silver film on its leaves and small strokes and dots on the underside of the leaf plate. These lesions are similar to those that spider mites leave on plants, but the traces of thrips bites are more pronounced. Since thrips are hidden in the substrate at the slightest danger, they can be very difficult to detect. In addition, they easily move from one plant to another with wings. How to get rid of thrips? First you need to thoroughly wash the orchid in the shower, then cut out all the damaged areas to a healthy tissue, sprinkle cuts with powdered charcoal and spray the flower with Fitoverm or Aktellik. Treatment with insecticides is repeated twice more with an interval of 10 days. All this time the plant should be quarantined until you are sure that you have destroyed all the pests. If there are few thrips on an orchid, instead of chemical preparations, you can use vegetable insecticides for processing - infusion of onions or garlic or oil water.
Thrips on violets
As in other flowers, flower thrips on the senpolia usually reveal themselves when most of the plants are already affected. Nevertheless, there is a way to cope with pests on violets literally at a time. 2-3 days before treatment, water your senpolia well. Before processing, wrap the pot with a plastic bag so as to protect the soil from water entering it. Rinse off the dust with violet running water, then lower the flower “upside down” into a deep basin with the following composition: 1 ampoule of Fitoverm and 25-30 ml of anti-flea shampoo for animals are dissolved in 5-6 liters of warm water. When mixed, the shampoo forms a foam, which must be removed, to the extent that the remnants of soap shreds are absorbed with toilet paper. The violet should be in the soap solution for 10 seconds, after which it is taken out of the water and turned very slowly so that the glass contains as much liquid as possible. Categorically it is impossible to shake and twirl a flower, trying to shake off water from it. Remove the polyethylene from the pot and thoroughly spill the soil with a solution of Actara and Fitosporin – M , prepared in accordance with the instructions. Hold the processed flowers in quarantine until you are convinced that there are no more thrips on them.
Garden thrips control measures
Fighting thrips on cucumbers
Most often, thrips on cucumbers can be found in the greenhouse. They settle on the underside of young leaves and feed on their juice, which slows down the growth and development of the whole plant. Light circles are formed at the puncture sites, and they are located so densely that they are found upon careful examination. In addition to bites, silver patches appear on the leaves - evidence that air has entered the leaf.
Thrips multiply very quickly, so the fight against them must begin immediately. If there are few pests, then you can treat cucumbers with infusions of garlic, onions or celandine, but if the moment is missed and thrips are spread throughout the greenhouse, resort to drugs such as Actara, Avertin N or Imidacloprid, from which they prepare an aqueous solution in accordance with the instructions . Do not forget to protect yourself with rubber gloves, goggles and a respirator when processing and tune in to the fact that you need several such treatments to completely defeat thrips.
Tobacco onion thrips affects the main parts of the plant - the feather and onion, but it is often difficult to figure out exactly which insect damages the onion. If you find small black dots on the plant, and in the axils of the leaves are light, mercury-like spots, you are probably dealing with thrips. Subsequently, the onion leaves turn yellow, starting from the top, and die off. The plant slows down development and forms small bulbs. Of onion crops, garlic is less likely to be infected with thrips, shallots are also quite resistant to this pest. Thrips for onions is most dangerous.
You can protect the planting of onions from thrips by organizing the correct crop rotation, that is, re-planting onions or garlic on the site no earlier than 4-5 years, and after harvesting, collecting and burning all plant residues. Do not forget in the fall about the obligatory digging of the earth: the pest hibernates to a depth of 7 cm. After collecting the onions in the greenhouse, do not forget to treat it with a solution of Karbofos. Remove weeds in a timely manner and sow only disinfected material.
If thrips is found, it is necessary to carry out fumigation with sulfur gas in the room where onions and sevoc are stored: 1 kg of sulfur is enough to process 1 m³ of storage. The fight against thrips on the onion bed is carried out by Actellik, Aktara, Mospilan , Fufanon, Fitoverm, Golden Spark, Karate or Vertimek. Recently, the Spintor insecticide, with which onions are processed every one and a half weeks, has gained popularity. In addition to insecticides, sticky traps can be used, and if there are few thrips onions, then infusion of onions, tobacco, celandine or zest decoction is used to destroy them.
Gladiolus thrips are a real disaster for these magnificent flowers. It reproduces more intensively in hot, dry weather and can produce up to seven generations in one season. Thrips cause serious damage to blossoming inflorescences: climbing into the buds, adult individuals and larvae make punctures in delicate petals, and after rain they become brown, as if burnt. Seriously damaged buds do not open and dry out. But not only gladiolus flowers suffer from thrips: the replacement bulb of the affected plant is formed so small and weakened that it dies during storage. With the onset of autumn, thrips make their way deep into the soil and settle on the bottom of the gladiolus corms, and after harvesting you bring pests to the store.
How to protect gladioli from getting thrips? Every autumn, collect and burn or plant all plant debris into the compost , dig up the soil, and dig up the corms that have been dug up before storing them and discard all specimens with mechanical damage, punctures and bites, dip the healthy corms into the Karbofos solution for half an hour, then rinse them in clean water, dry and only then store it at a temperature of no higher than 5 ºC: in such conditions, thrips dies. Before the spring planting, the gladiolus corms must again be etched in the solution of Karbofos.
From mid-June, cycle insecticide treatments for gladioli with alternating drugs. For example, you can spray the flowers with Karbofos or Aktellik twice, then carry out the treatment with Decis. The first two treatments are carried out with an interval of 7-12 days, and the next - after 25-28 days after the second.
Thrips on roses
On garden roses, thrips settle mainly in buds and feed on their juice, as a result of which the affected flowers do not open and dry out very quickly. Since thrips multiply and spread over the plant very quickly, you can lose all the roses if you do not decisively start the fight against the pest. Both at home and on garden roses against thrips, drugs such as Fitoverm, Aktara, Komandor and Inta-vir are used. With the solutions of these insecticides, the roots of roses are shed once every two weeks, and experienced gardeners recommend adding a little zooshampoo or grated green soap to the soil solution. Bushes are not treated with insecticides, as this can kill the bees. Affected buds need to be cut: they still can not be saved, but healthy flowers can be protected from infection by pests.
Means for thrips (drugs)
In order to surely get rid of thrips, you have to resort to processing plants with chemicals. Which of them are the most effective? And which are the least harmful to humans? We offer you a brief description of insecticidal drugs on sale.
- Agravertin is a biological preparation of intestinal contact action that is highly effective in controlling sucking insects. Consumption - 5 ml per half liter of water;
- Aktara is a highly effective intestinal contact insecticide that is rapidly absorbed by the plant;
- Actellik is an organophosphate insecticide with a wide spectrum of activity - contact-intestinal - against leaf-eating, sucking pests and ticks. Consumption - 1 ampoule per 1 liter of water;
- Vertimek is an intestinal-contact insectoacaricide to protect plants indoors, as well as indoor plants. Consumption - 2.5 ml per 10 liters of water;
- Decis is a broad-spectrum contact insecticide against leaf-eating and sucking pests that destroys both adults and larvae;
- Imidacloprid is a chemical substance, an insecticide used in the fight against harmful insects. Imidacloprid is used as an active substance in many modern drugs;
- Inta-vir - a drug for the destruction of insects in gardens, gardens and greenhouses, safe for pets and people. Consumption - 1 tablet per 2 liters of water;
- Golden spark - a highly effective insecticidal agent against insect pests;
- Karate is a contact action insecticide that is highly effective in pest control. Consumption - 0.5 ml per 2.5 liters of water;
- Karbofos is a moderately toxic pesticide from pests of fruit, citrus, vegetable crops and grapes. Consumption - 15 g per 2 liters of water;
- Mospilan is a fast-acting systemic insecticide that destroys pests at all stages of development;
- Spintor is a preparation of biological origin that has a unique mechanism of action against a huge number of pests;
- Fitoverm is a biological preparation that is a product of the vital activity of soil microorganisms and protects indoor plants from pests. Consumption - 2 ml per 200 ml of water;
- Fufanon is an organophosphorus insecticide with a wide spectrum of action, which has a contact, intestinal and fumigant effect.
The fight against thrips folk remedies
Although decoctions and infusions prepared according to grandmother’s recipes are not as effective as the latest chemical preparations, they are significantly less toxic to humans, bees, birds and pets. Therefore, in the case of an insignificant number of pests or for prevention purposes, it makes sense not to shoot the sparrows from the cannon, but to treat the plants with such folk remedies:
- 1 teaspoon of chopped garlic or onion, pour a glass of water and let it brew for a day, then strain and process indoor plants;
- fill a half liter can of dry marigold with water to the top of the can, leave for 2 days, strain and spray the plants;
- Pour 50 g of fresh leaves or dandelion roots with a liter of warm water and leave for three hours, then strain and use to spray the affected plants;
- 100 g of pharmacy chamomile, pour 1 liter of water, let it brew for half a day, strain, add 5 g of grated green soap to the infusion and treat the plants affected by thrips;
- half a glass of dry shredded tobacco or tobacco dust is poured into 1 liter of water, insisted for a day, filtered, added to the composition another 1 liter of water, stirred and used to treat plants from thrips;
- Fill 50 g of dried tomato leaves with a glass of water, leave for 3 hours, strain and add the infusion with water to a volume of 1 liter. Use for spraying plants;
- 50 g of freshly chopped leaves and stems or 100 g of dry celandine pour 1 liter of water, insist for a day, strain and process plants from thrips;
- put turpentine or minced garlic in a small container, put it directly in a pot to a thrips-infected indoor plant and then cover the flower for 3 hours with a plastic bag.
Types of thrips
As we already wrote, there are a lot of thrips in nature, and many of them are omnivores. But more often than others in indoor conditions, greenhouses and in the open ground there are such types:
- variegated thrips (lat. Frankliniella intonsa) - a dark brown bug with a length of 1.2 mm, which is a wide polyphage that parasitizes many cultivated plants and feeds on the juice of ovaries and flowers. Damages decorative, berry, fruit and vegetable crops. It occurs throughout the Palearctic;
- flowery Western thrips, also known as California thrips (Latin: Frankliniella occidentallis) - is also a wide polyphage that affects various cultures both in open and in closed ground;
- decorative thrips (Latin Hercinothrips femoralis) is a dark brown insect up to 1.7 mm long that damages almost all ornamental plants: chrysanthemums, orchids, crotons, gardenias, begonias, cacti, coles, callas, palm trees, dracaena, as well as bulb and Commeline crops. In the middle lane and areas with a cooler climate, this species lives mainly in closed ground;
- dracaenic thrips (Latin Parthenothrips dracaenae) - females of this species are yellow-brown, up to 1.2 mm long, males are slightly smaller and lighter. Dracenic thrips damage aroid and commeline crops, aralia, hibiscus, ficus and other plants. Under natural conditions, they live in the tropics and subtropics, and in regions with cooler climates they affect plants in rooms and greenhouses;
- rose thrips (lat.Thrips fuscipennis) - a wide polyphage, reaching a length of 1 mm. His body is brown, this species lives mainly on pink plants in closed and open ground, settling in flowers and buds;
- tobacco thrips (lat. Thrips tabaci) is a dangerous pest of many cultivated plants, preferring nightshade and umbrella crops. The color of the female can vary from light yellow to brown; tobacco thrips reach 1 mm in length. Under natural conditions, they are found in the south of Russia, in Ukraine and Central Asia, and in the north they prefer to harm plants in greenhouses and greenhouses;
- bulb thrips (lat. Liothrips vaneeckei) has a dark brown body up to 2 mm long and settles between the scales of the bulbs. Widespread;
- wheat thrips can feed on both cultivated and ornamental plants, but its favorites are members of the Cereal family: oats, rye, corn, barley, as well as plants such as cotton, buckwheat and tobacco. Wheat thrips do not disdain even weeds. Wheat thrips is a dark-colored bug, its female reaches 2.5 cm in length, and the male is half as long.
You should be aware that scientists discovered elements of social behavior in thrips: they, like bees or ants, gather in numerous groups in order to protect the clutch and larvae and lay odorous paths for group coordination.