Abstract
1. Different levels of nitrogen and water were applied to Satsuma orange in summer of 1968, and their effects on fruit quality and the number of flowers in the following spring were observed. All combinations of three levels of soil moisture (pF 2.3, 3.0, 4.0) and two levels of nitrogen (0 or 18 g/pot) were examined.
2. As a result, the soil moisture kept at pF 3.0 in summer was optimum for the best growth and quality of fruit. When soil moisture lowered to pF 4.0, fruit weight became extremely smaller and coloring of fruits was much more retarded. On the other hand, when the soil moisture increased at pF 2.3, soluble solids and total sugar contents in fruit juice decreased.
3. When nitrogen was applied in summer, fruit weight slightly increased, but soluble solids and total sugar contents in fruit juice were lowered and coloring of fruits was much retarded.
4. Although the number of flowers in the following spring increased with decreasing soil moisture, the growth of new shoot was checked. Even in such a case, when nitrogen was applied, the growth of new shoots was improved as well as the number of flowers.
