EFFECTS OF DIFFERENT K APPLICATION TIMES ON TREE GROWTH AND FRUIT QUALITY OF 'FUYU' PERSIMMON

This study was conducted to assess the effect of different application times of KCl as a supplemental K on tree growth and fruit quality of ‘Fuyu’ persimmon. The same amount of KCl was fertigated to pot-grown trees in July, August, September, and October, for three years. The pH and total N in the soil were not different in spring the following year, but K+ concentration was high for the October application. Late K application significantly reduced K concentrations of the leaves, fruits, and shoots. Different K application times did not affect tree growth measured by trunk cross-sectional area, shoot length, and leaf area. Fruit weight tended to decrease as K was applied late, suggesting the importance of K in early summer. However, skin color, soluble solids, and firmness of fruits were not consistently affected depending on the application times.