Black whiplash growing on diseased sugarcane tip How to control sugarcane smut

Sugarcane smut, also known as sugarcane whip smut, smut. The most obvious feature of the disease is that there is a black whip on the top of the diseased sugarcane. In the early stage of the formation of the disease whip, it was wrapped in a layer of silver-white film, then it broke, and a large amount of black powder was released, leaving only the heart pillar. Infected sugarcane sprouts early, the stem is slender, the leaf is slender, light green, the tiller increases, and the back tiller also grows black ear whip.

Sugarcane smut

The route of transmission and the conditions of disease: the infected soil and sugarcane with persistent root disease were the primary sources of infection. The germination temperature of chlamydospores was 6: 36 ℃, and the optimum temperature was 25: 30 ℃. High temperature and heavy rain in spring is beneficial to the occurrence and epidemic of sugarcane smut. The disease in the persistent root sugarcane field was more serious than that in the newly planted sugarcane field. The disease of using shoot seedling as seed is lighter than that of whole plant. The disease was more serious when applied too much nitrogen fertilizer.

Control methods: ① selected disease-resistant sugarcane varieties according to local conditions. ② practices crop rotation. Rotation with rice, corn, sweet potato, peanut, alfalfa and other crops. ③ reduced the number of years of persistent roots and planted disease-free seedlings. When leaving seeds, the tip seedlings of disease-free sugarcane should be selected in the disease-free fields. ④ pulled out the diseased plant before pulling out the black ear. Carefully cut off the black whip and put it in a plastic bag, take it out of the field and burn it. The diseased field does not leave a permanent root, and the stubble of the diseased plant will be burned. ⑤ should apply enough base fertilizer and pay attention to the rational application of nitrogen, phosphorus and potassium fertilizer. Timely irrigation, timely soil cultivation, prevent lodging and reduce the growth of lateral buds. ⑥ seedlings were sterilized. Soak the infected sugarcane seedlings in 52 ℃ hot water for 18 minutes for 30 minutes, and add 25% triadimefon wettable powder 500x solution for better effect. The sugarcane seedlings can also be soaked in 43% formalin solution of 1VR 100 for 5 minutes, and then the sugarcane seedlings can be covered with film for 2 hours. Or soak for 5 minutes with 70% mancozeb wettable powder 1 / 500 times. The seeds can also be soaked in 3% lime water for 24 hours.