In the past few years, the main diseases of tomatoes in winter were early blight, late blight and leaf mold. In recent years, due to the influence of tomato virus disease, many regions have planted anti-virus varieties, some varieties for certain fungi and bacteria. Sexual disease resistance is low. In addition to these three diseases, in the recent period, tomato leaf spot disease is also more serious in antiviral varieties. First, gray leaf spot disease. 1. Symptoms: On the early stage of disease, the leaves are covered with round or irregular dark brown spots that appear to be immersed in water and expand around the leaf veins to develop irregular lesions. The fading in the middle of the lesion is grey to gray-brown. The lesions are slightly concave, small and numerous, 2 to 4 mm in diameter, extremely thin, easily broken, perforated, or detached in later stages. 2. Prevention: After onset, 33.5% quinolinone 750 times solution or 600% copper noble solution plus 25% bromotriazole 500 times solution can be used for foliar spray, once every 5 to 7 days, and 2 to 3 times in succession. Second, bacterial pith. Bacterial pith is also known as bacterial pith necrosis. In winter, the management of tomatoes should be controlled. 1. Symptoms: Symptoms occur mainly in the stems of the lower part of the tomatoes. After the onset, a large number of adventitious roots are formed on the stems. When the stems are cut, transparent gelatinous substances can be seen in the medullary cavity. The leaves lose water and wilt. 2. Prevention: The key to bacterial diseases is early prevention. Here, we remind farmers who have changed their crops in the recent period. After planting the tomatoes, they should use 23% collaborative ammonia and copper plus 25% metalaxyl every 7~10 days. 500 times of cymoxanil is used for root irrigation, and 2 to 3 times in succession can have preventive effects. For the diseased plants, the above agents can be used to inject into the stem to control the development of the disease. For the prevention and control of tomato disease in winter, attention should also be paid to the combination with the management of the greenhouse. The daytime temperature is controlled at 25~30°C and the nighttime temperature is maintained at about 14°C. Relative humidity of more than 80% is conducive to the occurrence of most diseases, so it should be timely ventilation, reasonable watering, reducing the humidity within the greenhouse. At the same time pay attention to the pruning of the pruning to avoid excessive nitrogen fertilizer and improve the plant's disease resistance. Black Waxy Corn,Black Glutinous Corn,Glutinous Corn Kernels,Black Glutinous Corn Kernels Jilin Province Argricultural Sister in Law Food Co., Ltd. , https://www.nscorn.com