SEASONAL VARIATION OF MINERAL COMPOSITION OF KIWIFRUIT (ACTINIDIA DELICIOSA) IN NORTHERN GREECE

The aim of this work was to study seasonal variation of inorganic nutrients of leaves and bleeding sap of the kiwifruit cvs Bruno and Hayward.
Nitrogen concentration of leaves was high (4.5–5%) early in spring and was reduced to 1.7–2% at the end of the vegetative period.
Phosphorus concentration of leaves varied from 0.65% early in spring to 0.2% at the end of April.
The cv.
Bruno had greater P concentration than the cv.
Hayward.
Potassium concentration of leaves was high early in spring and stabilized to a minimum value of 0.5% at the end of October.
Calcium concentration was low (1%) initially and increased later reaching a maximum value of 3–3.5%. Magnesium varied from 0.4% to 1%. The micronutrients Mn and Zn also had the greatest concentration early in spring and stabilized to 80 and 15 ppm respectively.

The concentration of nutrients (N,P,K) in the bleeding sap were greatest initially, when bleeding started, and reduced after 1 month to 25% of the initial value.
Nitrogen and P concentrations of the bleeding sap were maximum in the morning and minimum after the noon.
On the contrary K concentration in the bleeding sap was constant during the whole day.

III International Symposium on Kiwifruit

I. Therios, Ch. Taraksi, S. Christaki, K. Dimassi-Theriou

https://doi.org/10.17660/ActaHortic.1997.444.40