Effect of Bagging and Time of Harvest on Fruit Quality of 'red Fuji' Apple in High Altitude Area in China

Introduction - The appearance quality of horticultural produce including fruits is a major factor influencing consumer acceptability. Two-year field experiments were conducted from May to September in 2013 and 2014 to determine the effect of bagging and number of days at harvest on apple fruit quality. Materials and methods - 'Red Fuji' (Malus domestica Borkh. 'Nagafu No. 2') apple was used. Two levels of bagging (i.e., bagged fruits and un-bagged fruits) and five levels of time of harvest including 170, 175, 180, 185 and 190 days after full bloom (DAFB) were studied in a randomized complete block design with three replications. The bags were applied at 35 days when most of the flowers were observed to have opened and then removed at 131 days after the bagging. The external and internal qualities of the fruits were assessed by physical and chemical analysis. Results and discussion - Bagging improved most of the appearance quality parameters including longitudinal and vertical lengths, skin color, cleanness and firmness of fruits. Spot sizes and spot densities decreased in bagged fruits. Soluble solids, soluble sugar, titratable acidity and vitamin C content were, however, high in the un-bagged fruits. The soluble solids and soluble sugar in both bagged and un-bagged fruits increased after 100 days storage. Titratable acidity in both bagged and un-bagged fruits, however, decreased after storage. Harvesting either 185 or 190 DAFB was more appropriate for maintaining the quality of both bagged and un-bagged fruits. Conclusion - In the high altitude area of China, bagging improved the appearance quality of the 'Red Fuji' apples. Better internal quality was, however, obtained from the un-bagged fruits. Harvesting 185 or 190 DAFB was most appropriate for improved quality of the apples in this area.