Disease and pest control of orchids

In the old society, precious orchid varieties were only monopolized by a few feudal scholar-officials and bourgeoisie. After liberation, the party and the people's government attached great importance to the cultivation of orchids, in addition to public garden cultivation, the majority of art orchid lovers also like to plant. However, orchids are not as easy to grow as ordinary flowers and are vulnerable to external diseases and insect pests. What's more, because growers lack scientific knowledge and experience, they lack systematic understanding of the causes and control methods of diseases and insect pests, and sometimes when they know that there are already diseases and insect pests, they do not know how to deal with them, which makes bluegrass suffer from spread and cause serious losses. According to the various situations and prevention methods that the author has come into contact with in many years of practical operation, the prevention and control methods are listed as follows:

(1) Diseases

Orchid diseases are mainly caused by poor ventilation, high temperature and humidity or frequent overcast and rain. Under the influence of these adverse conditions, orchid plants grow poorly and are easily infected by germs in the air or other diseases of neighboring plants, which are invaded through leaf stomata or wounds. Common diseases are:

Black spot: the disease initially shows round black-brown spots about 2 or 3 mm in diameter on the leaf surface, then gradually expands and increases, and in severe cases, it spreads locally to the whole tissue, resulting in the loss of the ornamental value of the leaves and the poor growth of orchids.

Prevention and treatment: strengthen ventilation, reduce humidity, and try to keep the leaves dry. Or spray the leaves with Bordeaux liquid. Cut off all the seriously damaged leaves and burn them.

White silk disease: is caused by fungi. It often occurs during the rainy period at the turn of summer and autumn, and there is a layer of white spider web mycelium spreading at the base of the leaf sheath and near the pseudobulm, which can make the bluegrass die quickly.

Prevention and treatment: after discovery, quickly eliminate the mycelium, spray Bordeaux solution and nicotine sulfate solution to sterilize. The injured strains were immediately isolated. Strengthen ventilation and light transmission.

Brown rot: it is a bacterial disease. It mainly occurs on new leaves and newborn pseudocorms. In the early stage of the disease, waterlogged spots first appeared on their leaves or pseudobulbs, swirling light brown, gradually turning into dark brown, wrinkling on the affected surface, and water-wet halos on the periphery. The disease develops very fast, often getting sick in the morning and turning the injured part into yellow and white at night, and the next day, it endangers the whole plant or the whole pseudocorm into soft rot. It mainly occurs from spring to early summer.

Prevention and treatment: quickly turn the basin to change the soil, cut off the disease part or the whole, and burn it immediately. Then disinfect the cut with sulfur powder or liter mercury water. Temporarily isolate and spray disinfection with a thousand-liter mercury solution or sparse nicotine sulfate solution.

Black virus: this is a disease transmitted by aphids. At the beginning of the disease, there are yellow spots on the leaves, and then become black spots or markings.

Prevention and treatment: keep the orchid place clean and hygienic, and often pull out the surrounding weeds. Strengthen disinfection. If there are too many diseased parts, cut it off and burn it.

(2) insect pests

Cymbidium: commonly known as blue lice, is one of the most common and common pests in bluegrass. This ostracod is covered with a brown flat round wax shell with a diameter of about 0.1 cm, shaped like a flea, and adsorbs on both sides of the leaf or inside and outside the leaf sheath. The worm uses filamentous mouthparts to suck the liquid in the leaves. After scraping off the insect body, there are light yellow marks on the leaf surface, such as the density of the group is high, the injured part becomes yellow gradually, the growth potential is weak, and the serious ones atrophy and die day by day.

Prevention and treatment: simple law, you can use brown brush or soft toothbrush along the leaf tendons, gently brush off longitudinally (such as excessive force, brush marks on the leaves, or even broken leaves). The insect body can also be gently scraped off with your fingernails. Or use cotton wool dipped in nicotine sulfate diluent, or stone sulfur mixture, wipe the leaves. However, several pieces of tissue in the center of the leaf bundle are relatively tender, and when wiping, the two fingers of one hand hold the base moderately, while the two fingers of the other hand hold the cotton stained with liquid medicine on both sides of the leaf and wipe it up, so it must be operated carefully, otherwise, the heart leaf is often pulled out or broken.

In addition to the above-mentioned liquid killing, strengthen the daily orchid place ventilation and light transmission, to avoid the surrounding environment too wet.

Ant

Langen is a fleshy root, accumulating a certain amount of water, slightly sweet, and the surrounding soil is loose, so it often attracts ants to build nests in the basin mud, making the soil loose and affecting root absorption.

In accordance with the law of prevention and treatment in ancient China, the orchid was raised in a shallow bowl to hold water, and the cymbidium basin seat was put into it (not immersed in the bottom hole) to prevent ants from invading. If you have found that there is an ant nest in the basin, you should immediately turn the basin to change the soil, or put something sweet and greasy around the basin to lure the ants out and hunt them step by step. Orchid pots can also be immersed in water, allowing water to seep into the bottom hole to drive and drown ants. In addition, you can sprinkle some DDT powder on the shelf to prevent ants from invading the orchid basin.

Mosquitoes and flies

The place of raising orchids is relatively damp and easy to breed mosquitoes and flies, which not only hinders the safe operation of the staff, but also pollutes the leaves, which is very unsightly. But also because mosquitoes and flies are easy to bring a variety of germs, causing infections and other diseases.

The prevention and treatment method removes the surrounding weeds, garbage and other objects, fills up nearby low-lying, stagnant pools, or inverts unnecessary water containers to reduce their breeding sites. Raise swimming fish in a watering tank to keep the water from giving birth to larvae. Drugs are often used to disinfect the surrounding environment.

Earthworm

The environment around Lantai is damp and easy to breed earthworms. Especially in the rainy season, earthworms often climb up the orchid platform and creep into the soft basin soil to feed, making the basin mud layer loose and full of worm droppings, which not only does not benefit the growth of Langen, but also hinders the outlook. When these conditions are found, fine lead wires or bamboo sticks can be used to pierce into the dung to induce earthworms to be caught or killed one by one. In addition, the orchid basin can be immersed in water for a while, driven out, and caught one by one. In order to put an end to this disease, BHC powder is often sprayed around the Lantai column to kill or dispel it.

Red spider

The insect is small and scarlet, often clustered on both sides of the leaves, sucking juice or epidermis from the leaves. After the injury, the light ones cause rough or mottled foliar tissue, while the heavy mesophyll dries up and gradually dies.

Use cotton wool to wet sparse dimethoate or fish rattan semen and wipe it off step by step.

Caterpillar

There are many kinds of larvae of butterfly moths. Often lodging in the trees around the orchid, eating leaves, falling by the wind and near the orchid, and then climbing up the orchid, infringing on the orchid leaves, buds and so on.

The prevention and treatment method regularly sprays the surrounding trees with insecticide solution, or directly capture it and kill it.

(3) Animal damage 1. Cat pee

Livestock cats often like to defecate in the potted orchid topsoil, and then cover it up with melons, disturbing the basin, drowning by the cat's urine, and Langen is very perishable. Before getting pregnant, domestic cats like to chew green and tender leaves, and orchid leaves are no exception.

The method of prevention and treatment does not drive or discipline the meshing leaves at any time.

Sparrow damage

Because Langen is soft and moist, sparrows often like to take sand baths in the soil, tumbling and disturbing the basin mud to reveal blue roots, false bulbs, or be injured as a result.

The prevention and treatment method placed several colored cloth flags between the pots and bowls, which were swayed by the wind and scared them not to go.

Snail dung

The place where orchids are raised is shady and humid, and snails and crickets survive. They hide in dark bricks and gravel piles or in basin bottoms and holes during the day, as well as under nearby shady wells and water tanks, crawling and foraging at night, except for eating young new leaves. It sticks and secretes silver-white liquid where it goes, which can affect the orchid leaves.

The prevention and treatment method is used to trap, kill, or catch at night and then put into salt water to kill. Remove the surrounding rubbish and grass so that there is no place to hide. Or sprinkle BHC powder around the orchid column to prevent climbing.

Many of the above-mentioned diseases and insect pests, in addition to appropriate drug contact, drive away, maintain the surrounding environmental hygiene, so that diseases and insect pests can not survive. Strengthening daily management, promoting strong roots and luxuriant leaves, and increasing resistance is also one of the measures that can not be neglected to avoid diseases. When changing varieties or buying back, we must pay attention to whether there are any diseases and insect pests. After bringing them back, it is best to carry out disinfection and prevention work first. If it has been found that there are diseases and insect pests, and the young are out of control, they should be burned immediately to put an end to the disease.