`Fuji' is becoming one of the major apple cultivars around the world. However,
poor coloration has been a serious problem in affecting fruit growers' profit from this cultivar. Various measures have been tried to improve fruit coloration, but
few have been successful. Although ethephon is effective in promoting anthocyanin synthesis in early cultivars like `McIntosh' and `Delicious' apples (Edgerton and Blanpied, 1970; Unrath, 1973; Greene et al., 1974), it is not effective in late cultivars like `Fuji' (Curry, 1994). Fruit bagging improved red color of apples (Fletcher, 1929; Proctor and Lougheed, 1976; Arakawa, 1988), but its labor intensive nature limits its application. Therefore, the fruit industry desires an effective and economic method to improve fruit coloration in this important cultivar.