Rational use of drugs

Fungicides are agents for the control of crop diseases. We usually have to choose according to the different properties and modes of action of different types of fungicides when we control orchid diseases. One is protective fungicides, which are used to deal with plants or their environment before pathogens invade. Plants need to be used before they are not exposed to germs or diseases, such as Bordeaux solution, stone-sulfur mixture, mancozeb, mancozeb, etc.

There is also a kind of therapeutic fungicide, which we often come into contact with, which is characterized by internal absorption. This kind of fungicide is used when the pathogen has invaded the plant or the plant has been susceptible. At this time, it is used to reduce or eliminate plant diseases. In the early stage of plant disease, the effect will be better.

The initial and peak stages of the disease of the same pathogens are also different, which are greatly affected by the external environment, especially the growth and development of the infected crops and the temperature and humidity. (therefore, we have to raise strong orchid seedlings). When preventing and controlling diseases, we should be familiar with the life habits and epidemic laws of pathogenic bacteria, and we can do a good job in disease prevention and control according to different seasons and temperature environment, which plays a great role in the effective efficacy of drugs. The crop diseases caused by all kinds of pathogens are different, and the symptoms are obviously different, so it is necessary to prescribe the right medicine when choosing fungicides. And the drug effect is significant, long-lasting, should not blindly pursue the high efficiency, broad spectrum, or even "omnipotent", let it ten thousand kinds of diseases, I only have one kind of medicine. This is definitely not going to work. When using drugs, we should pay attention to prevent the development of drug resistance of bacteria, that is, we can not use the same fungicide continuously, nor can we use the same kind of fungicide several times in a growing period, especially for internal inhalers. For example, internal inhalers can be used in combination with chlorothalonil, mancozeb and so on or in rotation.

Our daily use of drugs should be in accordance with the law of bacterial infection, take corresponding prevention and control measures. When using fungicides to spray orchid plants directly, attention should be paid to the influence of natural conditions to prevent efficacy failure or drug damage. When the temperature and humidity are high, the concentration of the agents used can be reduced appropriately, and the agents that are easy to decompose or volatilize under strong light should be carried out in cloudy days or in the evening.

Different pesticides have a certain range of use, only by deeply understanding them and mastering their use characteristics, can we correctly select pesticides and achieve twice the result with half the effort. Carbendazim is a widely used internal absorption fungicide, which can control dozens of fungal diseases. Ascomycetes and half-known bacteria are particularly sensitive to this drug, but they are ineffective to diseases caused by bacteria and oomycetes in fungi. In the case of accurate diagnosis of fungal diseases and repeated use of carbendazim, phenylamide pesticides (such as metalaxyl) should be considered. These drugs are mainly used for downy mildew, Phytophthora and Pythium caused by oomycetes, but have poor effect on diseases caused by other fungi and bacteria.

Chlorothalonil is a non-internal broad-spectrum fungicide, which can prevent a variety of plant fungal diseases. It can prevent spore germination, hinder mycelium development and spore formation, and control diseases resistant to carbendazim. However, the control effect on diseases caused by soil-borne rot mold is not good.

Therefore, often change fungicides, (Huakang is said to be able to kill all diseases, I do not know whether it is true or false, I dare not take it lightly when using it, and I still mix it with other fungicides) to strive for maximum protection of the orchid strain from the disease. Orchid long's health, orchid friends heart is also happy.