Planting technology of navel orange: how to prevent and cure the physiological diseases of navel orange?

How to prevent and cure the physiological diseases of navel orange? Please introduce that the main physiological diseases of navel orange are fruit cracking disease, sunburn disease, and navel yellow disease. The prevention and control methods of navel orange fruit cracking disease can be listed as follows: first of all, the varieties (lines) with strong cracking resistance should be selected for the prevention and treatment of navel orange fruit cracking disease. generally, the varieties (lines) with oval fruit shape, small navel or closed navel have better cracking resistance, such as Newhall, etc.; secondly, we should strengthen scientific management and enhance tree power. Especially in the dry period from the plum rain to the autumn rain, we should do a good job in water management, so as to irrigate or spray water in time, keep the soil moist and promote the normal growth and development of fruits. Thirdly, foliar potash fertilizer was sprayed continuously for 2 times during the period of rapid expansion of fruit. Foliar potash fertilizer can choose 0.2% potassium dihydrogen phosphate or 0.3% potassium sulfate compound fertilizer, and in the first and middle of July, the mixture of "920" with a concentration of 200 mg / L and 800 times of methyl topiramate and an appropriate amount of fragrant paste can heal the cracks and prevent fruit cracking from happening again. Prevention and treatment of navel orange sunburn disease orchard covering straw is the basis of preventing sunburn disease; planting forage grass or interplanting green manure in orchard can reduce sunburn disease; in high temperature season, do not spray pesticides such as oil emulsion and stone sulfur mixture, so as not to aggravate the occurrence of sunburn disease. In the early stage of sunburn, stick white paper on the sunburn fruit surface, and pull branches and leaves to block the fruit to reduce direct sunlight exposure. Regular irrigation or spraying in high temperature seasons in summer and autumn can prevent and reduce the occurrence of sunburn. The prevention and treatment of navel orange navel yellow disease begins with the cultivation of healthy trees, appropriate application of nitrogen fertilizer to improve tree nutrition level and nitrogen metabolism function, and then pull Qiangwang autumn shoots into a drooping or horizontal state before flowering, so that the vast majority of flowers bloom downward, reduce Xiangyang fruit and prevent navel yellow. From the first ten days of June to the last ten days of July, combined with fruit protection, the "920" solution of 40 mg / L was sprayed twice, and from late July to late August, 600 times of "xanthate" solution was sprayed on the navel of the fruit to inhibit the occurrence and spread of umbilical yellow disease. Click to get more navel orange planting techniques click to get more fruit planting techniques