Effect of phosphate applications on the growth, yield and fruit quality of young Satsuma orange trees on yuzu and trifoliate rootstocks
1966 Volume 35 Issue 2 Pages 98-105
Details
1966 Volume 35 Issue 2 Pages 98-105
1. The effect of phosphate applications to young Satsuma orange trees planted in concrete frames on the growth, yield, fruit quality and leaf composition were investigated during 1959 to 1963. Two- year-old tree grafted on yuzu or trifoliate rootstock was planted on March, 1958, and each tree received 12.8g of phosphate as a nutrient solution during 1958. In the subsequent year, phosphate application was changed from the rate of 0 to 2, although nitrogen, potassium and magnesium were equally applied in each.
2. The growth of young trees on the average of 4 years data obtained from 1959 to 1963 did not show any effects by the phosphate applications. However, the growth of young trees on the same soil which had not been applied nutrient solution in the previous year was considerably improved by phosphate applications.
3. The yield, contents of soluble solids in fruit juice and of inorganic elements in leaves were not affected by phosphate applications during 1960 to 1963. The content of acid in fruit juice, however, was significantly lower in phosphate treated plots than in untreated plot, as shown in the average data from 1960 to 1963, and in 1962.
4. Phosphate application tends to decrease reddish color of the fruits.
5. The yield, content of soluble solids in fruit juice obtained from young Satsuma orange trees on trifoliate rootstock increased more than that on yuzu root stock.
6. The content of soluble solids in a large fruit obtained from the trees on trifoliate rootstock was less than that in a small one, however, the reverse tendency was found in fruits on yuzu root stock. It is also noted that possitive correlation was found between the content of acid and that of soluble solids in fruits on trifoliate rootstock in non-phosphate plot, and negative correlation was found between them in fruits on yuzu rootstock in non-phosphate plot.
7. Young Satsuma orange trees on yuzu rootstock used in this experiment seemed to be not so vigorous as adult trees on the same rootstock are.
