Vegetation shade must prevent infection

In order to raise orchids, it can be said to do everything possible, all the corners are used, balconies, windows, and so on. I wish I could replace the gums in the boudoir with orchid racks, or throw out the pots and pots and stoves and put them neatly on the row of orchid pots. At this time, I can't help but miss the big courtyard with green moss in my hometown. If it is full of orchids, several big trees in the yard will be protected, saving me the trouble of shading the orchid all day long. In a word, it is hard to raise orchids in this place of town.

If in the park, or some green space, pine shirt willow, lush, green deep show, continuous connection, thick and thin, green leaves, green grass, the wind blowing, cool all over the body. I don't usually stare at the solidified young men and women in the western sculptures in the bushes. I keep touching this leaf and pinching the trunk. In my heart, I kept exclaiming: how good this place is to raise orchids for me! How many pots can you hold?

Shading by big trees is good, forming a microclimate, high humidity, low temperature, purifying air, preventing wind and reducing noise, known as natural air conditioning. If an orchid friend has his own courtyard with lush trees and lower orchid pots, he really admires people. Back to big trees to enjoy the cool, open-air orchid cultivation, weekly planting of small trees, shrubs, can effectively reduce the temperature, for orchids to create a suitable environment, casual management, orchids also live moisture, which is like my balcony to raise orchids, sunshade net heat insulation, baby orchids scorched, a moment dry, a moment wet, busy round and round, worry about it.

However, it is good to grow orchids and trees in the courtyard, but the courtyard is not nature. Orchids are ecologically balanced and everything is safe from each other. Human settlements, a single ecological imbalance, there are more or less a small number of diseases, can be prevented, wouldn't it be better.

Most trees carry germs and pests. Although they are woody and herbaceous, they are both plants. Although they are different, they are more or less the same. If the bacteria completed the incubation, spores completed the production and spread process, the number of diseases accumulated to a certain extent, bacteria from the incubation period to the infection period, encountered a suitable climate environment, I am afraid it will cause harm to the orchid. We must remember the eight words "prevention first, comprehensive prevention and control". When applying medicine, orchid friends can spray the small trees and other flowers near the orchid basin.

Some bacteria are highly contagious. Through vector transmission (mainly insects, especially aphids and leafhoppers, followed by soil nematodes and fungi. Secondly, it was passed. Pollen transmission, pollen often carries a virus, so through pollen can spread germs. Virus diseases are mostly systemic infection, no symptoms, easy to be confused with non-infectious diseases, and often need to be confirmed by a certain way of infectious test. The ways of transmission of plant virus diseases are as follows: mechanical (friction) contact transmission, grafting transmission, medium (including insects, nematodes, fungi, mites and dodder) transmission, pollen and seed transmission and so on. Because the virus is an idiopathic parasite, the source of its infection is related to living organisms (living animals, plants or mediators). Infection requires the virus to come into contact with living organisms. For example, juice friction inoculation, to use fresh virus juice, the purpose of friction is to cause minor injuries on the surface of host plants, so that the virus may enter living cells, excessive damage caused by tissue necrosis is not conducive to virus transmission. Aphids, planthoppers and other piercing mouthparts insects feed on plant juice more easily to meet the two requirements of plant virus transmission.

Usually, Lanyou likes to use vines to build a frame and lower the orchid pot. if it is a grape, you need to be careful. The grapes are susceptible to black rot, gray mold, brown spot, etc., especially anthracnose. If the environment is airtight, the temperature is 29m. 35. At C, the disease developed rapidly. I've learned my lesson about that. Fruit growers in grape producing areas apply medicine once every ten days to take precautions in order to protect leaves and fruits. This anthrax has a serious attack, and if there is negligence, it will cause heavy losses.

There are more than 30,000 kinds of plant fungal diseases, accounting for 80% of plant diseases. About 200 kinds of plant bacterial diseases are known.

Several kinds of trees are easy to get sick, and bacterial leaf blight often occurs in sweetwood. In general, the incidence of plantation is more than 50%, and when it is serious, it can reach 100%. Anthracnose is common in Huaiqiuling area of Anhui River. Poplar black spot disease can make poplar leaves black and dry and fall like Liang Zhuhua butterflies. If the orchid is placed under the tree, it must be prevented from falling on the flowerpot to avoid infection.

Sycamore, mainly anthracnose, the disease often occurs on leaves, petioles and shoots, symptoms of leaf chlorosis, gradual expansion, rupture in the middle of the disease spot, early fall of diseased leaves, serious, causing leaves and tender slightly withered to death. The disease belongs to half-known subphylum, anthrax, spread through the wind, Rain Water and so on. Indus Acacia rain, Indus night rain, autumn color to empty boudoir, night sweep big tung leaves. Sycamore and drizzle, to dusk, dribs and drabs. Xiao Xiao Yu on the sycamore leaves. What a beautiful realm! However, the meaning of the Song ci painting hidden killing, not careful, orchids were infringed, so you should be careful.

Orchids in open areas should be kept away from tobacco, medicinal plants, etc. Tobacco is the most seriously affected by crop diseases. It is reported that the damage rate is 64%. Tobacco diseases include more than 100 parasitic and non-parasitic diseases in the world, and nearly 20 major diseases in China. Mosaic disease, anthrax and so on are more serious. However, medicinal plants will suffer from black spot, rot, leaf spot, root rot, anthracnose and so on. The pathogens are similar to orchid pathogens, so we should pay attention to guard against them.

Pinus tabulaeformis, citrus, Chongyang wood, Haitong, poplar and so on are vulnerable to soot disease. when the leaves and tender shoots of the above trees are covered with soot, the light and function of the trees will be weakened and wither will be caused in serious cases.

There are about 30 kinds of tea plant diseases in China, most of which are fungal diseases, including moire leaf blight, anthracnose, white star disease and black spot disease. Raise orchids should also stay away from this thing.

For ornamental plant diseases, some orchids like to put orchids together with other flowers to increase air humidity. Some ornamental plants are prone to diseases, such as rose black spot, chrysanthemum brown spot, camellia anthracnose, bacterial soft rot, evergreen anthracnose, jasmine white silk disease, gentleman orchid white silk disease and so on. If found, throw it away quickly, and then protect the orchid spray.

Insect pests: open environment is more vulnerable to insect pests, all kinds of pests in the absence of anti-quilt or lack of natural enemies, doubt and determination, tiger steps, sharp thorns to show strength, secrete poison to play fierce. Or suck the juice, or eat the leaves. There is a kind of jujube inchworm, when it occurs, it can eat up the leaves of the whole tree. Various pests not only bring physiological harm, but also infect germs, which is even worse. In dry weather, trees sometimes produce mite damage, which extends to the orchid basin. The chlorophyll of orchid leaves was destroyed, and the number of mites was 30. The first generation can be completed in about 5 days above C, and the harm is serious.

The pathogens of plant diseases are biological pathogens (the organisms that can cause plant disease are called pathogens, referred to as pathogens, including fungi, bacteria, mycoplasmas, rickettsia, viruses, viroids, nematodes and parasitic seed plants. The diseases caused by) are contagious and are called infectious diseases or parasitic diseases. Orchids are endangered by contact period and invasion period, and the invasion methods include direct invasion and external invasion. Rainy and humid environmental conditions for the formation of fog droplets are beneficial to the invasion of such pathogens.

Plant diseases can be divided into three types: (1) fungal diseases are the most important types of flower diseases. Fungi are lower plants without chlorophyll and are invisible to the naked eye. It can not make its own nutrients and use mycelium to absorb nutrients in flowers. Fungal spores spread everywhere by wind, rain, insects, etc. (2) bacterial disease bacteria is a very small single-celled organism, which does not have the differentiation of vegetations and reproduction. It absorbs nutrients through the cell membrane and propagates by division. Bacterial infection is mainly transmitted through stomata, dense glands, wounds and other ways, generally through running water, wind and rain, insects, soil and residues of diseased plants. (3) virus disease virus is a tiny parasite. It can only be seen by electron microscope that the virus propagates only in living flower cells. The virus is transmitted through insects (mainly piercing and sucking mouthparts, such as aphids, red spiders, etc.) and mechanical damage. Various pathogens depend on various interrelationships among organisms, such as predation, parasitism, competition and reciprocal symbiosis.

We know that about 70% of plant diseases are caused by fungi. Among plant infectious diseases, fungal diseases are the most common, accounting for more than 70-80% of all plant diseases. Each crop is affected by several or even dozens of fungi. Diseases caused by fungi, bacteria and other pathogens are contagious and are called infectious diseases. Anthracnose and bacterial diseases often occur in high-temperature and humid environment, while Botrytis cinerea occurs in cold and humid climate. Powdery mildew is more likely to occur in facility cultivation with poor ventilation. If the orchid site is well lit, well ventilated and the surroundings are clean, the germs are not easy to attack.

Generally speaking, plant pathogen virus symptoms can be divided into the following types:

First, discoloration: including "mosaic", "mottled", "broken color" three types. "mosaic" refers to the appearance of dark and green patches on diseased leaves. "mottled" means that there are chlorotic spots on the diseased leaves, the spots are larger, the edges are not obvious, and the distribution is uneven. The phenomenon of "discoloration" is called "broken color" on the petals.

Second, chlorosis, yellowing: the whole plant or some organs are light green or yellow.

Third, spots, stripes: often occur in leaves, stems, fruits and other parts, such as necrotic spots, necrotic stripes, chlorotic spots or chlorotic stripes.

Fourth, ring spot, oak leaf: both often appear on the leaf, and the concentric spot is called "ring spot". Those with leaf-like discoloration patterns along the veins are called "oak leaves".

Fifth, bright vein, yellow vein, vein band: bright vein and yellow vein are the early stages of mosaic symptoms. First, the transparent vein is called "bright vein", then the yellow vein is called "yellow vein", and the "vein band" turns dark green along the leaf vein.

Sixth, wrinkled leaves, rolled leaves: deformation of local tissues or organs. The growth of leaf vein is inhibited, the mesophyll still grows, the leaf wrinkles and the leaf margin curls up or down.

7. Clumping and dwarfing: the terminal buds of diseased plants are suppressed, a large number of lateral buds sprout, and those with clumps of branches are called "clumps" or "clumps". The shortening of internodes and the uniform dwarfing of plants are called "dwarfing".

Ear process: protuberances are produced on the veins on the back of the diseased leaves, which are shaped like ears and are called "ear processes".

Therefore, if we find the above symptoms in the surrounding vegetation in the orchid environment, we should consider taking measures to prevent the orchid from being infected.

The number of diseases is a development process from less to more and distributed from point to area. In a suitable season, all kinds of diseases are developing at different rates, and their growth rates are different, even if they are the same disease, the growth rate and extent of the number of diseases are also different under various conditions. According to the difference in the appearance of the disease comes from the characteristics of the disease itself, including the number of generations of re-infection, reproduction rate and mortality, as well as the efficiency of transmission and other factors. Even if the number of bacteria is very low, some diseases will cause a certain degree of harm as long as the conditions are right, while other diseases may not cause a pandemic even if the conditions are right, and this kind of diseases will cause harm only when the number of bacteria is large.

The time required for the accumulation of bacteria in different diseases varies. Some diseases in a growing season, as long as the conditions are appropriate, the accumulation process can be completed, resulting in various degrees of epidemic infection.

We can also see that the disease spreads. Re-infection is mostly aboveground diseases, local diseases, but also some systemic diseases; the mode of transmission is mostly air-borne and wind-rain-water transmission, as well as insect transmission, the transmission distance and efficiency are generally large, and the wind and rain will not only break the orchid leaves. moreover, the soil with bacteria on the basin or the soil on the ground will be splashed on the orchid or orchid leaves, resulting in the occurrence of plant brown rot. As the saying goes: put it on the shelf, don't put it on the ground. In addition to ventilation, I am afraid that when there is a strong wind and rain, the bacteria-carrying soil on the ground will be splashed on the orchid leaves.

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Pathogens tend to have a long life and strong resistance to adverse environment, except that they are easily affected by the environment in the invasion period, once the invasion is successful, they are little affected by the environmental conditions, so the epidemic of the disease is less controlled by the environment. Bacteria in the small number of bacteria, sporadic disease, easy to be ignored, once the number of bacteria accumulated to a certain extent, and then encounter susceptible varieties, the climate is conducive to invasion, it will be serious harm, loss is a foregone conclusion, so do not take it lightly.

For some diseases, the overwintering bacteria come into contact with the host one after another, and the infection time is longer, and the disease occurs first and later. In fact, it takes a certain time for any plant disease to produce progeny inoculum after the host is infected, and there is a lag time from infection to infection; incubation period. It is known that some bacteria can lie dormant for years and will make a comeback if the conditions are right. Therefore, the initial source of bacteria should be eliminated, the harm should be reduced through cultivation measures and the application of chemicals, and good results can be achieved in orchid garden hygiene and disinfection. At the same time, we should have a long-term point of view and take effective measures to prevent the accumulation of bacteria.

Caused by bacteria infection, it is called infectious disease, which is caused by pathogens, susceptible plants, environmental conditions and man-made factors. If the pathogen infects plants, the disease may not occur, and whether the disease can occur depends on the disease resistance of plants. If the disease resistance is strong, the disease will not occur or the disease will be very mild. In a word, if the orchid is strong and the resistance is strong, the disease will be reduced.

To sum up, the use of trees for orchid shading has both advantages and disadvantages, generally speaking, the advantages outweigh the disadvantages, trees can reduce the temperature and increase humidity. The only thing to pay attention to is to prevent trees and vegetation from being infected with germs and even orchids. The courtyard pays attention to the high walls to keep out the wind. As a result, poor ventilation increases the chances of germs. (it clears up when it snows fast)