Chemical control of sorghum rust

Symptom sorghum rust begins to occur before and after heading. Red or purple to light brown spots were formed on the leaves, and then with the expansion of the pathogen, the spots expanded and formed an oval protuberant heap of summer spores on the leaf surface, which revealed beige powder, namely summer spores. In the later stage, the teliospore pile was formed in the same place, which was darker and larger than the microspore pile. Regular occurrence of pathogens overwintering with winter spores on diseased remains, soil or other hosts. When the conditions were suitable in the following year, the teliospores germinated and basidiospores invaded the young leaves to form the gonadal organ, and then the rust organ was produced on the back of the disease spot. After flying and spreading, the rust spores germinated when there were water droplets on the leaves, and also invaded from the leaves to form summer spores and summer spores, which were transmitted by air flow and re-infected many times. When sorghum is close to harvest, teliospores are formed in the place where summer spores are produced, and winter spores are used to survive the winter. It is easy to get sick in the rainy season from July to August. In the early stage of the disease, 25% triadimefon wettable powder 1500 Mel 2000 times, or 40% carbendazim suspension 600 times, or 80% Shiprolol (Dysen zinc) wettable powder 600 times 800 times, or 25% benzonazole EC 3000 times, once every 10 days, for 3 times in a row.