Sweet potato black skin is actually sweet potato black spot disease, also known as sweet potato black shank disease. The disease can occur from the nursery period, the field growth period and the harvest storage period, directly causing dead seedlings, rot beds, rotten pits, causing serious losses. The main symptoms of the disease: After the potato sensation, the pathogens penetrate deeper into the lower part of the potato meat, making the surface of the sweet potato appear hard black skin (see above). The individual potato meat turns dark green and bitter. The diseased department was lignified and dry rot. And diseased potatoes contain toxic substances (alcohols) and cannot be eaten. At the early stage of infection, the potato seedlings produced a black spot with a depression in the basement or the base of the young stem, and gradually spread to the ground, becoming a long lesion, and continuing to expand to make the base of the seedling stem dark. As soon as the diseased seedlings were colonized, the leaves turned yellow, the plants were short, and finally the infected plants rotted underground. In the past few years, the benefits of planting sweet potatoes have always been promising. Many crops appear to be planted continuously, coupled with extensive management and management in the field, resulting in more and more sweet potato black spot disease in recent years. Many cropping areas rely on chemical pesticides alone for their poor control. Therefore, comprehensive prevention measures should be adopted to strictly control the occurrence and spread of the disease from many aspects such as nursery, field management, and storage. Drugs to treat potato seedlings in advance. The base of the potato seedlings is about 3 to 5 cm, and the seedlings are immersed in the base for 5 to 5 minutes with 50% dexamethasone or 50% thiophanate-methyl 500 to 600 times or carbendazim or 700 times, and then transplanted to prevent disease. better. Black-spotted fungus infestation of potato seedlings at the seedling stage mainly infringes on the white part near the ground, so it is recommended to adopt high-cutting seedlings to reduce the field disease. Generally cut seedlings 4 to 5 cm above the ground. Strengthen field management and prevent diseases in advance. Spray azoxystrobin 800 times solution or 50% carbendazim WP and 75% chlorothalonil 500 times solution before potato tuber for prevention in advance, once every 7~10 days, spray 3~4 times, and Alternating drugs can be used to improve the control effect. Strengthen management during storage. The storage period is the period with the greatest harm and the greatest loss of black spot disease. The source of bacteria in the storage period mainly comes from the diseased tubers in the field. The pathogens invade the tubers through the wounds caused by transportation. In the early stage of storage, the incidence is not obvious. When the high temperature, high humidity, and poor ventilation conditions are encountered, the diseases begin to increase. In general, pathogens develop faster than 15°C, and potato pieces below 10°C are susceptible to freezing. Therefore, storage temperature should be controlled between 10 °C ~ 14 °C, relative humidity between 80% ~ 90%, is the key to safe storage prevention and control of melasma. If you use a centralized kiln to store sweet potatoes, you should strictly control the admission of susceptible sweet potatoes into the pit before entering the kiln. Textile Ultrasonic Welding Machine Product categories of Textile Ultrasonic Welding Machine, we are specialized manufacturers from China, Ultrasonic Welding Machine For Fabric, Ultrasonic Welder suppliers/factory, wholesale high-quality machine of ultrasonic welding R & D and manufacturing, we have the perfect after-sales service and technical support. Look forward to your cooperation! Textile Ultrasonic Welding Machine,Ultrasonic Welding Machine For Fabric,Ultrasonic Velcro Welding Machine,Webbings Welding Machine Wuxi DIZO Ultrasonic Technology Company , https://www.dizosonic.com