Effect of Environmental Conditions on the Contents of Sugars and Ascorbic Acid in'Senshu' Apple Fruit

Abstract

The effects of various environmental conditions, including exposure to light and fruit load, on the contents of sugars and ascorbic acid in'Senshu' apple fruit, which is suitable to a high quality juice, were investigated.
(1) The contents of glucose, fructose and sucrose decreased by shading and bagging. The content of sucrose was greatly reduced by shading. The content of ascorbic acid was also reduced by bagging and shading. (2) Defoliation treatment reduced the total sugar content, especially sucrose. The ascorbic acid content was also reduced. Overcropping treatment reduced the fructose and sucrose contents greatly, and the ascorbic acid content was also reduced. However, the levels of the sugars and acid in better coloring fruits were higher than that of lower coloring. It was suggested that among the sugars sucrose was especially affected by the light conditions and fruit cropping, while ascorbic acid was related to photosynthate in addition to exposure to light.