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Changes in fruit characteristics of `Fuyu´ pc rsimmons during maturation were observed after the application of several growth regulators including ethephon, daminozide, and paclobutrazol. Fruit firmness gradually decreased, whereas sugar content increased consistently up to 32 days after treatment. Fruits treated with 100ppm ethephon showed lowest firmness during maturation. Fourty-two days after treatment, the highest fruit firmness was observed in 2,000ppm daminozide＋50ppm GA₃ treatments. Sugar content was not significantly influenced by growth regulator application except for paclobutrazol treatment which resulted in significantly low sugar content. Total chlorophyll, chlorophyll a and b were rapidly reduced immediately after treatments and then gradually leveled off. Total chlorophyll in control fruits rather stayed unchanged during the early stage of maturation and decreased at the later stage of maturation. Total chlorophyll content was lower in the 100ppm ethephon treatment. Ethephon application increased total carotenoid in the fruit flesh, while daminozide＋GA₃ and Paclobutrazol treatment decreased the pigment. Total crude protein and peroxidase activity remarkably changed during maturation in all the treatments but with opposite patterns. Total protein changed slightly at the early stage of maturation but increased rapidly at the later stage of maturation. In contrast, peroxidase activity decreased significantly at the early stage of maturation and then slightly changed during the later stages of maturation. Among treatments, ethephon treated fruits tended to show higher protein consent during maturation.
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