Tomato heart rot is a relatively serious physiological disease in greenhouses in recent years. The diseased tomato fruit appeared in the interior of the pulp, with an irregular brown necrotic mass near the center of the fruit. The diameter was about 2-3 cm. In severe cases, the brown color affected the whole flesh, resulting in inferior fruit quality, but the external appearance was normal. This heart rot also often causes empty fruit or poor fruit coloration. Causes of heart rot are complicated, with physiological calcium deficiency, boron, or climatic factors as the main reasons: First, the swelling of the first 1-2 layer of tomato colonized in early autumn is in the period of high temperature, high temperature and dry, and the root system Dysplastic plants are prone to heart rot; the other is planting disease-resistant varieties or delaying proper colonization; thirdly, heart rot is often mixed with umbilical rot. In the flowering period, it is particularly severe when it encounters continuous yin weather. It mainly infects young fruit, but at this time, the symptoms are not obvious. With the growth and development of the fruit, the damage is aggravated. To strengthen the cultivation and management, rational watering, fertilization (special attention should not be excessive application of nitrogen fertilizer), in the fruit growth and development of calcium supplementation, even the weather, pay attention to ventilation and reduce humidity, reduce the chance of pathogen infection. Control methods: 1. Select a variety with strong resistance to heart rot. In combination with site preparation, the application of organic calcium powder is 50-80 kilograms per mu and a large amount of organic fertilizer. 2. In order to prevent the occurrence of heart rot, we must start by improving the ventilation and light conditions of the plants, deep plowing the soil, fully expand the root system, prevent excessive high temperature and drought, and balance the relationship between vegetative growth and reproductive growth. When the tomato is planting water, 10-20 kilograms of seaweed fertilizer should be applied per acre to promote early seedling easing, and the roots should be developed to improve the resistance of tomatoes. When the tomato buds appear, spray 25-ml fruit and vegetable calcium fertilizer + 1.5g Bac-protector + 15g Nifone boron to a bucket of water (15 liters) for 2-3 consecutive times, preferably 5-7 days apart. 3. Artificial cooling is used when the temperature of the fruit in the 1-2 layer of the tomato is high. Such as cover shade nets, leaf spray, etc., can reduce the incidence of the disease. 4. Simultaneously smoke the shed with chlorothalonil aerosol. On sunny days, the pesticides such as foliar sprays and buprenorphine were sprayed every 7 days. Double Bit Key Mechanical Door Lock Double Bit Key Mechanical Door Lock,Mechanical Gate Lock,Safe Mechanical Lock,Double Sided Mechanical Lock Zhejiang Tilanco Industry&Trade Group Co., Ltd , https://www.tilancogroup.com