First, the disease often encountered in tomato seedlings is catastrophic disease.
The main symptom of tomato cataplexy disease is that at the time of tomato seedling, the seedling is prone to lodging, which is the phenomenon of being broken and broken after growing. The main diseased part is the junction between the stem and the root of the tomato. The rotten state is the water-stained state that people often say. Once this happens, the tomato’s roots will wither, lose water, die, and the tomato will no longer grow.
The main cause of cataplexy disease is that under such an environment of low temperature and high humidity, the germs spread into the greenhouse through rainwater and soil on our feet, and then transplanted when sowing. When it is transmitted to tomatoes, the bacteria are already carried in the soil, so it will quickly develop disease when it encounters the low temperature environment of rain and rain. Low temperature is generally around 10 degrees Celsius, soil temperature is generally around 15 degrees Celsius, and it is particularly prone to outbreaks.
When controlling this disease, the most important thing is to prevent it first, that is, after the end of the tea planting, some lime, sterilizer, etc. must be used to kill all the bacteria in the greenhouse soil. This is the best way to keep in mind during the later greenhouse nursery process. Do not bring the environment into the greenhouse through external soil and water. Once this kind of disease is found in the greenhouse, it is most effective to control it with chemicals first. In terms of pesticide selection, 68% refined metalaxyl manganese-zinc water dispersible granules and downy mildew water spray were generally used for spray irrigation, and the effect was good.
Second, the common disease of tomatoes in greenhouses is gray mold.
This kind of disease mainly occurs during the growth period of tomato. In the greenhouse, tomato is cultivated in winter and spring. The main disease that occurs is gray mold. The most obvious symptom of red mold disease is the onset of leaf edges. It spreads inwardly in the shape of a wheel. It is extremely helpful for the spread of this disease when the humidity is high. It is the object of gray mold infection. In some greenhouses, many vegetable farmers do not pay attention to the outbreak of gray mold on a cloudy day. When the disease is very serious, the petals of the tomato are easily infected during the flowering stage of the tomato, and the fruit stalk expands like a tomato.
Seriously, there is a large brown gray spot where the fruit comes in contact with the stalk. Its color is grayish white with signs of rot. It will grow hairy at the diseased part, which is the traditional thick mold. It is very serious. The main reason for the outbreak of tomato gray mold is because of the presence of this bacterium, which will quickly erupt in the appropriate temperature and humidity environment in the future. Therefore, the effective measures to prevent gray mold are also in the early stage of prevention. To control the greenhouse, the temperature and humidity of tomatoes should be strictly guarded against dead gray mold. The prevention is the first priority. If once the outbreak, the gray mold in tomato greenhouse, you need to quickly prevent and control through the agent: 25% azoxystrobin suspension agent 1500 times the liquid + 50% fluconitrile wettable powder 5,000 times the liquid spray prevention, in severe cases After removing all disease and fruit, all plants, stems and leaves were treated with 1200 times solution of 50% pyrimicycline water dispersible granules.
The third type occurs in greenhouses. The common disease in tomato planting is tomato virus disease.
Among many viral diseases, the yellow leaf curl virus is the most serious. Once the yellow leaf curl virus is obtained in the greenhouse, almost the entire tomato plant will be extinct. This is by no means sensational. This yellow leaf curl virus was first found in tomatoes in the south. After 2009, it gradually began to erupt in concentrated areas of tomato planting in Hebei and Shandong provinces. The virus spread very quickly. Agricultural insights only remember that the tomato greenhouses that got this yellow leaf curl virus that year were almost all empty, vegetable farmers friends, no profit. The symptoms of this viral disease are as yellow as its name, and the leaves are curved, which are its typical symptoms. In the early stage of tomato liver disease, it is the uppermost new leaf that starts to show yellow curl. The phenomenon of leaf roundness appears. The most typical symptom of yellow border is curling up. Once the new leaves at the upper leaf growth point begin to appear in this condition, the entire tomato spider will stagnate and grow very slowly, hardly move, and become smaller and significantly shorter between nodes. In the late stage of the onset of the greenhouse, the whole tomato will dwarf its growth and development and stagnation, it will be almost impossible to flower and bear fruit, and the fruit will not turn normally, which will result in the reduction and yield of the whole greenhouse tomato. There are only two routes of transmission of viral diseases. As we all know, one is transmitted by tobacco planthopper, and the other is grafted. The way that tobacco planthopper spreads is that after carrying the virus into tomato plants, the tobacco planthopper exists in the body for a lifetime, and its toxicity is very long lasting. The grafting method is well understood. There is no problem with the grafted rootstock grafting the rootstock. If the virus is carried in the scion area, if the graft is normally grafted on the rootstock in the future, the whole tomato plant will be diseased. In the following we learned the transmission of the yellow leaf curl virus through various analysis and analysis. The most important thing was the transmission of the first tobacco planthopper. Therefore, to control the yellow leaf curl virus in tomatoes in greenhouses, the most important thing is to cut off the transmission of tobacco planthoppers and eliminate the number of tobacco planthoppers in greenhouses.
The incidence of yellow leaf curl virus in greenhouses is also closely related to the tomato cultivation season. Because the tobacco planthopper lives in a higher temperature environment, the incidence of tomatoes planted between May and July is generally higher, and the incidence of tomatoes planted around October and winter tomatoes in the fall Just lower. From here we can know that the temperature is very obvious for the tobacco planthopper, so only by cutting off the environment of the tobacco planthopper can the virus be controlled. Therefore, in the control of tomato yellow leaf curl virus in greenhouses, the main method is to choose tomato varieties that are resistant to disease and resistant to viruses. The second is to prevent the contact between tobacco planthopper and Wen’s tomato through physical control. Therefore, in the process of tomato seedling breeding, planting, and cultivation, 60 mesh insect nets should be set up to prevent the invasion of tobacco planthoppers. Insect nets must be installed on the upper and lower air outlets of the greenhouse. At the same time, the yellow stickworm board that traps insects must be set up in the greenhouse. This is mainly through the use of the tobacco repelling habits of yellow planthoppers. Planthoppers, through this biological control to achieve the purpose of eliminating tobacco planthoppers. At the same time, these virus diseases can now be purchased in many agricultural dealers, as well as agricultural dealers with pesticide business licenses. Pesticides can also reduce the virus’s effects on plants through pesticide control, especially greenhouse tomatoes. However, the curative effect of this treatment is not obvious, so the most important thing in preventing and treating viral diseases is early prevention.
Post time: Feb-04-2020