桃樹の養分吸収量について
1957 年 26 巻 4 号 p. 267-276
詳細
1957 年 26 巻 4 号 p. 267-276
1. In order to estimate the amounts of the nutrient elements absorbed by 2 years old (Koyo-hakuto) and 7 years old (Mishima-hakuto) peach trees, all parts of these trees were separated, and trunk, branches and roots were divided into new and old tissues of bark and wood, and weighed, analysed. In addition, the roots system of these trees were researched by the circle form method.
2. Average dry weight of new tissues in these trees were as follows.
_??_ 3. The amount of these new tissues was about 89% of the total weight of 2 years old tree, and about 59.2% in 7 years old tree. While, the sum of leaves, one year old branches, flowers and fibrous roots was about 64.5% of the total new tissues, and about 44% in 7 years old tree.
4. Analytical data showed that one year old branches had the highest contents of N, P2O5 and K2O in top parts of the tree, and these contents have a tendency to gradually decrease from 2 years old branches. There was every indication that new bark content was higher than old bark and new wood was higher than old wood in each partitions. Root parts was the same trend to top parts on each partitions, but in each parts the tendency was obscured.
5. Average total amounts of nutrient elements contained in new tissues were as follows. (per tree)
_??_ *2 years old tree were planted at a rate of 75 trees per 0.1 hect and 7 years old tree were planted 48 trees per 0.1 hect. and yield of fruits was 1761kg (458kan)
The amounts of absorbed nutrient elements, when yield of fruits was 100kan (375kg) per 0.1 hect. (1 tan)
7. Range of roots in 2 years old trees were not observed more than radius of 1m. and at a depth of 90cm, and sum of roots in a partition of radius of 1m and at a depth of 30cm was about 85% of the total roots weight. In the case of 7 years old trees, range of roots were not observed over a depth of 90cm, but the horizontal spread were found to radius of 3 or 4m, and sum of roots in a partition of radius of 1 m and at a depth of 30cm was about 67.8% of the total roots weight.
