Take equal amounts of Bordeaux liquid and other drugs, for example, generally to be used before June. Navel orange ulcer disease prevention and control methods: strengthen fertilizer management, irrational fertilization will disrupt the tree's nutrient transport and growth, making the tree's twitching period, the number of twitching, the number of twitching and the speed of aging and so on inconsistent. Generally in the case of more nitrogen fertilizer will promote the occurrence of disease, such as the application of a large number of fast-acting nitrogen fertilizer before and after the summer solstice is prone to promote a large number of summer tips, so it is necessary to control the amount of nitrogen fertilizer application, increase the application of potash.