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The effects of defoliation treatments during maturation on fruit quality of ´Fuji´ apples were determined to investigate the reasonable defoliation method. Two different defoliation treatments were done: half of cluster leaves were defoliated on 20th September and the other cluster leaves and the lower leaves of bourse shoot were defoliated on 5th October (divided defoliation), and all cluster leaves and lower leaves of the bourse shoot were defoliated on 5th October (one time defoliation). Surface red color of ´Fuji´ fruits was significantly increased by defoliation treatments, and no significant difference was found between treatments. Soluble solids, occurrence of watercore, titratable acidity, fruit diameter and fruit firmness were not influenced by defoliation treatments. Photosynthetic rate of cluster leaves and bourse shoot leaves were decreased rapidly after 4th October and upper leaves of the bourse shoot is the best and middle leaves of bourse shoot, lower leaves of bourse shoot, cluster leaves in decreasing order. Chlorophyll contents of bourse shoot leaves were decreased gradually with the approach of harvest time and upper leaves is the best and middle leaves, lower leaves in decreasing order. From these results, the practical defoliation method to improve surface red color of ´Fuji´ apple was defoliation of all cluster leaves and the lower 1/3 leaves of bourse shoot at the same time in early October.
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