Pest control

Diseases and insect pests refer to the harm caused by insects and fungi to orchids. Relatively speaking, the harmfulness of insect pests is much less than that of fungi. Pest control is relatively easy to control, but the prevention and control of bacteria is very difficult. This is because the control of bacteria is academic and scientific, and the author has not engaged in scientific research in this field. There is little knowledge about the generation, nomenclature, gene arrangement, variability, low temperature tolerance and high temperature resistance of pathogens, as well as the temperature and humidity suitable for reproduction, so there is no scientific basis for talking about the prevention and control of diseases and insect pests. However, in order for us to plant orchids well or talk about pest control based on experience, we intend to discuss the methods of orchid pest control with orchid friends, and urge experts to make a scientific judgment on common orchid pathogens. The prevention and control of diseases and insect pests should focus on prevention and treatment as the center, and conscientiously do a good job in prevention.

1. Strong grass is unstained, large grass strong seedlings are generally very healthy and do not carry bacteria, and have strong disease resistance. therefore, the selection of seedlings is very important, strong seedlings are the fundamental guarantee of resistance and resistance to bacteria, and orchid plants are the same as human beings, the weak and sick, therefore, the selection of seedlings should not only be cheap, but also strong seedlings, to find ways to strengthen the grass can reduce the harm of bacteria.

2. No matter what kind of seedlings should be sterilized before potting, the normal seedlings can be sprayed with 1 to 2000 methyl carbendazim, mancozeb or carbendazim, and the diseased seedlings should be soaked in medicine to rinse the cold dry pot. Spraying and soaking plants should not be used repeatedly in the prevention and control of diseases and insect pests in the future, lest orchid plants produce antibodies and can not achieve the effect of prevention and control.

3. The disinfection of plant materials can be done after exposure to the sun in the summer day under normal circumstances, and the used plants should also be used after exposure. It is best not to use the diseased orchid plants. If they need to be used, they should be boiled at high temperature. The orchid pot should be heated to more than 80 degrees on the fire to avoid bacterial regeneration.

4. both downhill grass and ramet orchid seedlings are injured on the body surface, and the wound is easy to cause infection. All the bacteria infected through the roots are harmful to the orchid plant, easy to infect, and not easy to detect, so the orchid strain should wipe the wound with chlorothalonil or topurazine dry powder in time, put it in the basin after fully cool in the sun, soak it in 1 / 1000 chlorothalonil solution for 10 minutes after rinsing, and soak it in the basin after full cooling, and the orchid plant should be light in the basin. Do not squeeze the plant material forcefully, damage the root system and the Reed head, adjust the plant material to semi-wet and semi-dry (containing about 50% water) and place it in a cool place, and pour water thoroughly for 3-5 days according to the water retention capacity of the plant material, which can effectively avoid wound infection. The orchid plant maintained on the balcony should avoid the orchid frame as far as possible to avoid mechanical injury and infection when the wind makes the orchid leaf swing. Bacterial infection is the result of bacterial replication, and the so-called bacterial replication is the mass reproduction of pathogens. Therefore, the fundamental measure to prevent and control germs is to restrain the reproduction of pathogens, but our understanding of germs has no sufficient scientific basis, and there is no accurate method. Therefore, it is very important to prevent bacterial infection. The above four tasks are the main preventive measures for us to plant orchids. It is still necessary to carry out germ control work in combination with weather temperature and humidity. Practice has proved that it is very important to do a good job in germ control on overcast and rainy days during the growing period.

5. Pruning diseased leaves: as mentioned earlier, bacterial infection is the result of bacterial replication, so timely cutting off diseased leaves is one of the main means to cut off pathogens. When pruning diseased leaves, we should pay attention to the following problems: scissors should be carefully disinfected. Scissors can be wiped with alcohol, potassium permanganate and other solutions, only one pot of grass can be cut after each disinfection, and when the second pot is trimmed, scissors should be wiped with cotton balls to avoid cross-infection. Try to finish the pruning work before 20 degrees Celsius, according to the author's observation, most germs are more active when the temperature is above 20 degrees Celsius, especially when the temperature is about 28 degrees Celsius, so the pruning work should be finished before the bacteria are active. Pruning diseased leaves should be chosen at 10:00 on a sunny morning, because the air humidity is low at this time, which can avoid the bacteria carried in the air to infect the wound, at the same time, it is conducive to the wound formation and delusion on the same day. Reduce the risk of reinfection. The air is too humid to be trimmed on cloudy days. After pruning, the orchid plant should not be sprayed with water (fertilizer) within 2 days, but can be managed normally after 3 days.

6. Drug prevention: when the orchid plant enters life for a long time, we have to work on the prevention and control of pathogens. Whenever the air is humid and rainy, there are many germs in the air. Cephalosporin, penicillin, streptomycin and so on can be sprayed with water 1000 times. Adding a small amount of liquid foliar fertilizer can help the drug to penetrate the foliar wax layer and improve the preventive effect. When the temperature reaches more than 20 degrees Celsius, streptomycin can be used to irrigate the root once. With the gradual rise of the temperature, the bacteria are more and more active. You can choose Baishouqing, Tobujin, carbendazim, mancozeb, poison Anke, virus will be gram, virus fast gram and other spray prevention, the disinfectants used in the basin should not be reused, and the drugs used in a year should not be reused for the third time.

7. Drug treatment: the above measures are the prevention measures of orchid plant diseases and insect pests. Although we have carried out serious prevention work, some orchid plants may still have lesions when the temperature is 25 degrees Celsius. Therefore, it is necessary to carefully observe the growth of orchid plants at this time and deal with the lesions in time. Carbon maggot disease is one of the common diseases, and the effective treatment is timely detection and treatment. At the beginning of the disease, the pathogen is very small, shaped like a needle tip, and can be found in time by careful observation. It can be cured by smearing the diseased site with 1 stop 50 and scrubbing it clean after 4 days. The earlier the treatment, the better. Carbon maggot pathogen replicates very quickly on the leaves of orchid plants. When the ambient temperature is about 28 degrees Celsius, it can replicate exponentially in 12 hours, which is harmful. Some people use "daconine" (a drug for beriberi) to smear the affected area with good results. Rust spot, mosaic disease and other treatments are the same as above, and the drugs used are sold in local seed stations. In the practice of planting orchids, we may encounter a small number of stubborn cases, which can not be cured for a long time and handed down from generation to generation. Such orchids can carry out appropriate ramets in winter, trim the residual leaves and old roots after ramets, smear the wounds with drugs, soak them in water for 20 minutes after 5 hours (general medicine 1/l000), cool in the back basin, and the old plants and orchid pots should be disinfected at high temperature. (song Mingyuan, Mo Shi Caotang, Anhui Province)