What are the reasons for the occurrence and prevalence of peanut rust?

What are the reasons for the occurrence and prevalence of peanut rust? Peanut rust is a fungal disease caused by peanut stalk rust. The summer spores are yellow, round or nearly round, with micro-thorns on the surface, and there is a germination hole on each side of the middle part of the summer spores. Most summer spores produce only one germination tube, the appressorium is formed at the top of the germ tube, and the infection filaments invade peanut from the appressorium. Summer spores can germinate only when there are water droplets or water film. The ability to withstand low temperature is strong, but the ability to withstand high temperature is poor. In general, the germ tube invaded the tissue after 65 hours, and the hyphae continued to grow and produce haustorium. 7 days later, needle-tip-sized white spots appeared and began to produce summer spores. 8 days later, the white spots turned yellow-brown and formed a summer spore pile. 10 days later, the epidermis of the summer spore pile ruptured, sending out summer spores to continue infection. During the period of peanut growth, the spread of peanut rust was mainly caused by local bacteria, but the pathogen of early spring in northern peanut area also had the problem of non-local pathogens. The main factors affecting the occurrence and prevalence of peanut rust are: first, the amount of overwintering wormwood. If the amount of overwintering bacteria is large, peanut rust may occur in the following year. Second, climatic conditions. In general, temperature is not a limiting factor. The main factors affecting the prevalence of rust were Rain Water and fog dew. The occurrence of rust was serious because of more days of rainfall and fog dew. The third is cultivation and management. Spring peanut early sowing disease is mild, late sowing disease is serious; autumn peanut early sowing disease is serious, late sowing disease is mild; continuous cropping land disease is serious, rotation land disease is mild; paddy field occurrence is serious, dry field occurrence is light. The disease was serious in the fields with partial application of nitrogen fertilizer.