EFFECT OF NPK FERTILIZATION TREATMENTS ON ANNA APPLE TREES

This investigation was carried out in 1992 and 1993 to study the leaf mineral content fruit set, yield and fruit quality of Anna apple trees, grown in sandy calcareous soil, as affected by different NPK fertilization treatment added to the soil N fertilizer either alone or in combination with K or P or both increased fruit set, yield and fruit peel chlorophyll.
Nitrogen fertilizer alone decreased fruit total soluble solids (TSS) in both seasons.
However, the NPK fertilization treatment decreased TSS in the second season.
Both P and K treatments increased the average fruit weight and juice acidity.
Nitrogen fertilizer alone or in combination with K increased leaf N, Ca and Mg contents.
On the other hand, NK treatment decreased leaf Na content.
The PK treatment increased leaf K content and decreased leaf Na content.
The NPK fertilization treatment increased leaf N,K and Cu contents in both seasons, but decreased leaf Zn and Mn contents in the season.
It could be concluded that the best yield of Anna apples trees grown in sandy calcareous soil was obtained by using a combination of 2 Kg ammonium sulfate, 2Kg potassium sulfate and 1 Kg superphosphate / tree.

III International Symposium on Mineral Nutrition of Deciduous Fruit Trees

S.M. El-Shazly

https://doi.org/10.17660/ActaHortic.1997.448.92