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Seasonal changes in nitrogenous compounds and carbohydrates were monitored from 1-year-old persimmon seedlings (Diospyros kaki cv. Fuyu). Extension growth of the seedlings stopped by September 1. Stem cross-sectional area (SCSA) increased most extensively in September. Normalization of seedling height with SCSA to minimize the variations among the samples resulted in a decrease in height after August 1. When the seedlings were actively growing in July and August, the leaves accounted for 56 to 65% of total dry weight. Root dry weight was 75 to 82% of the total during the dormant season. Amino acid contents in leaves, stem and roots of a seedling increased from July to September I, but decreased in October 1. Amino acids in the leaves accounted for about 50% of the total in July, but the proportion decreased to 7% by November 1. Amino acid contents in stem and roots steadily increased after October 1; the roots accounted for about 87% of the total. Protein in all the seedling parts increased from July to September 1. Leaves and the roots contained 53% and 41% of total protein respectively during September. Protein in root on January 1, 1994, accounted for 93% of total of seedling. Soluble sugars in the leaves increased during the growing season, but declined after September. Soluble sugars in the roots and stem increased from July 1, 1993, to January, 1, 1994. Roots accounted for about 90% of the total in January I, 1994, but decreased with new growth of the shoots. Starch contents in the leaves increased from July to August, and then decreased. Starch in the roots gradually increased by November 1, 1993, accounting for about 85%n of total of seedling. A rapid decline of root starch was observed from November. A further of starch decline in root was found in April as well as the onset of new growth.
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