Cracks on apple fruit surface are common physiological diseases in recent years. Friends of fruit farmers generally call it apple crack disease. Except Marshal was a strong disease-resistance apple, other apple varieties had varying degrees of incidence, while the incidence of severe diseases in Fujia, Fuji, became a limiting factor affecting the yield of high-quality apples and fruit farmers. Causes 1 Long-term drought in young fruit, little rain, fruit cell expansion is slow, late irrigation or sudden rainfall, and the relatively large amount of rainfall, the rapid expansion of cells, peel cells and fruit cells in synchrony, resulting in cracks, cracks in the peel cells. Ruptures occur in the fruit's rapid expansion or near maturity. 2 When the content of potassium, calcium and boron in the soil is insufficient or the nitrogen content is too high, apple crack disease is intensified. During the expansion after the fruit development stops, the nitrogen content in the pulp increases too fast, which will aggravate the cracking. These cracks initially spread along the lenticels, and later formed significant transverse cracks. 3 canopy cover, poor ventilation and light transmission, the fruit surface moisture can not be distributed quickly, eventually leading to cracks at the cracked wood cork, light fruit spots become dark, severe fruit surface crack into a strip wound, fruit wilting late, lost goods value. It has been observed that the positive surface of the fruit is usually evenly colored and cracks rarely occur; the shade surface of the fruit, the shaded area adjacent to the two fruits, or the fruit surface that clings to the leaves are susceptible to cracking. 4 Rainwater inflows into fruit bags, especially in rainy days, due to high humidity and long duration in the bags, causing cracks and cracks on the fruit surface. 5 Bagged fruit bags are also prone to cracks in the event of rain or extreme hot weather. Precaution 1 Increase bio-organic fertilizers, increase tree vigor, and improve tree-regulatory capacity and resistance. 2 Within 40 days after flowering, ensure sufficient water supply; regular irrigation of fruit should be performed regularly to ensure that the pericarp cells and pulp cells grow steadily at a uniform rate. 3 optimize the tree shape, remove excessive branches, open the light path, dredge the waterway, reduce the humidity inside the crown, reduce the low light efficiency crown area, and create favorable conditions for the uniform coloring of the fruit. 4 Minimize the use of pesticides that are irritating to the skin cells in young fruit, and actively promote orchard sowing techniques to regulate soil moisture and nitrogen supply. When bagging, the bag must be fastened tightly so that rain does not flow into the bag. 6 When taking off the paper bag, avoid dry heat, windy, and sudden heat change weather. Ankle Surgical System Medton Medical , https://www.medtonmedical.com