What is the reason why tomatoes wither as soon as they bear fruit? How to promote tomatoes to bear more fruits?

Fusarium wilt is a soil-borne disease, and it is a systematic disease that harms tomato. Tomatoes may get sick from seedling stage to mature stage, and germs invade from root or root neck, so the symptoms gradually appear from bottom to top, which is highly contagious, but the disease is slow. Sclerotinia sclerotiorum is a fungal disease. Ancient vegetable fields are very common. Like Weifang, the incidence of tomato Sclerotinia sclerotiorum is high, because it is an "old vegetable garden". Tomato Sclerotinia sclerotiorum spread rapidly, but the pathogen mainly invaded from the base of the diseased petiole, the leaves withered and died first, and the pathogen invading the stem slowly attacked. At first, the tomato stems showed sunken water stains and gray spots, and then rotted, and the stems were covered with sclerotia and died. The disease is progressing slowly.

Tomato soft rot is a bacterial disease. There is a wound on the branch. When bacteria come in, the early lesion is blue-gray, short, wet and rancid, and it can expand in the later stage, sometimes to a long grayish brown spot over 1 m. The stem turns dark brown and smells bad. After falling into the water, the diseased area shrinks, white and hollow, which can cause disease. But the course of disease is slow. This pathogen can overwinter in bacteria or soil, and can survive for 1 ~ 6 years, with the longest record of 25 years. High temperature and high humidity are beneficial to the occurrence of this disease. The wound on the plant is a channel for the invasion of germs. On the other hand, this pathogen spreads along rain, water, humans, insects, farm tools, soil with bacteria, nematodes, fertilizers with bacteria and so on. After heavy rain or persistent plum rain, the recovery is fast, and the temperature rises quickly, which is conducive to the epidemic of diseases.

Noble diseases are difficult to treat. From the selection of disease-resistant varieties, rotation with Gramineae crops for more than 3 to 5 years, adjusting soil pH, is not conducive to the growth of pathogenic bacteria. In planting management, early seedling raising and early transplanting are advocated to avoid high temperature season and reduce diseases. Make full use of organic fertilizer, avoid flooding, drain water in time after rain, and avoid the damage of water to roots. In daily management, especially in breeding, it is necessary to guard against attendance, pull out bottles of wine in time, destroy and disinfect sick blood.

Tomato plants are prone to get sick in places with high temperature and high water content. Continuous planting all the year round may cause a series of diseases, leading to the decline of tomato yield and quality. This is a continuous cropping obstacle. Its solution can use microbial agents to improve soil and dissolve venom. Of course, there are many kinds of companies that grow disease-resistant plants in the mayor/market. Tomatoes will be destroyed in a few days, so in order to keep out the rain, we must play salsa in time. Be careful not to water the results. Watering can spread the palms of crops. It leads to insufficient nutrition and causes tomato diseases. Bacteria overwinter in soil or seeds, spread through wind and rain, and then invade the stomatal epidermis of tomatoes, causing diseases. When the temperature is 20 ~ 25 degrees Celsius, especially in rainy weather, it is easy to get sick. Georgia, low-lying areas, plots with too much thin water or poor ventilation are easy to get sick. Be sure to pay attention.