Comprehensive Prevention of Orchid Diseases

Comprehensive Prevention of Orchid Diseases

At the peak of the disease, I posted an article in "Chinese Flowers" in the hope that it would be useful to you.

Orchid diseases are caused by fungi, bacteria and viruses, which mostly occur in leaves, followed by flowers, pseudobulbs and roots. the incidence and prevalence of orchids are significantly higher than those of other flowers. Once bluegrass is sick, it loses its elegant and elegant charm, and its appreciation value decreases. The occurrence and development of orchid diseases are closely related to the cultivation environment and management level of orchids. As long as we know the causes of orchids, we can effectively prevent these diseases.

Create a good environment for orchid planting

The growing environment of orchids is very conducive to the reproduction of bacteria, especially fungi. Moist and dreary air, dark space, transparent and nutrient-rich soil provide excellent conditions for the growth of fungi, so there are many fungal diseases in orchids. How to overcome the unfavorable factors in the environment? First of all, the air is required to be clean. The less dust in the air and the less dust in the surface area of orchid leaves, the less likely the bacteria will spread. Plant orchid environment should try to avoid facing the streets, factories and other seriously polluted places. Secondly, it requires moderate shading, different orchid varieties have different light requirements, shade is too large, bluegrass is green and weak; shade is too small, leaves are withered, leaves are withered and scorched, which may lead to disease. Only when the shading is moderate, the orchid leaves are firm, bright and resistant to disease. It is best to let orchids bathe in the morning light, because the morning light is not only conducive to the growth of orchids, but also has a certain bactericidal effect. It is necessary to maintain a certain humidity and flow of the air, too much air humidity is conducive to the reproduction and growth of diseases, and too small is not conducive to the growth of bluegrass; in addition, the flow of air can prevent the air from becoming dull and keep the air fresh, so controlling the humidity and flow of the air is also the key measure to prevent diseases. Finally, the soil should be disinfected before use. The soil is steamed through in a pot and then cooled naturally. This method can effectively kill fungi and bacteria in the soil.

Cultivate strong seedlings and strong plants

Those who are strong and healthy have strong disease resistance, and so is bluegrass. If an orchid is thin and damaged, it is easy to get sick. Cultivating strong seedlings is an important means to improve the disease resistance of orchids. In addition to having a suitable environment for the growth of orchid, the most important thing is to provide comprehensive and rich nutrients for the growth of orchids. The nutritious soil must be rich in organic matter, nitrogen, phosphorus, potassium and trace elements, and reasonable topdressing of nitrogen, phosphorus, potassium and various trace element fertilizers is also the key measure to cultivate strong seedlings. There is no scientific reason to say that fertilization will increase the incidence of orchid diseases. In the case of lack of other nutrients, partial application of nitrogen fertilizer will make bluegrass tender, weak and susceptible to disease, but reasonable fertilization will only make bluegrass more resistant to disease, and can also prevent the occurrence of diseases such as physiological deficiency of bluegrass. In addition, ramets should be appropriate, do not blindly split for temporary commercial interests, this violates the law of orchid growth, so that bluegrass damage, poor roots, seedlings are not strong, become susceptible to disease, will only be counterproductive. In addition, all kinds of bluegrass have different resistance to different bacteria (this situation does exist), and beginners can raise varieties that orchid friends think are not susceptible to disease.

Eliminate the source of the disease

The source of the disease comes from the source of the disease and its own source of disease. The first is to eliminate foreign sources of disease. In the introduction, try not to introduce diseased orchid, the lower orchid should cut off the withered, diseased leaves and shrunken old bulbs. The introduced bluegrass should be cultivated alone for a period of time to observe whether there is any disease. General diseases are classified into routine management after treatment, and should be resolutely burned if they are diseases that have never been seen locally.

The second is to reduce the disease source of orchids. As the leaves of bluegrass are evergreen for several years, even if they wither, they do not leave the mother plant, so once the disease occurs, the source of the disease will exist for a long time, and the new buds will be surrounded by germs immediately. Therefore, it is necessary to cut off the diseased and dead leaves in time, and the cut leaves should be taken out of the orchid field and burned.

Medicament prevention

Chemical prevention is not only the last pass of orchid disease prevention, but also an effective method. The agents that can be selected for fungal diseases are carbendazim, thiophanate, chlorothalonil, mancozeb and so on, and streptomycin and chloramphenicol can be used for bacterial diseases. Be sure to take medicine before or at the initial stage of the disease, so that you can get twice the result with half the effort. The disease is more likely to occur once every ten days than in the region or season, while the disease is less likely to occur once a month or once a quarter. Application method: first, all kinds of agents are used alternately. If carbendazim, thiophanate and mancozeb are used alternately, the preventive effect is good, and it is not easy to make the bacteria resistant to drugs. Second, the dose can be lightened properly, and the lowest concentration marked by the agent is better. Third, the selection of drugs for symptoms, the sensitivity of different bacteria to drugs is also different, such as anthrax with carbendazim, topiramine and other prevention; bacterial soft rot with chloramphenicol, Fusarium stem rot with Dexong has a very good prevention and control effect (this is the result of my many years of experiments, we might as well try), these two diseases can achieve the effect of complete treatment through these two kinds of drugs. (Liu Jingqiu)