THE EFFECT OF INTER-ROOTSTOCKS ON THE CONTENT AND SEASONAL CHANGES OF MAJOR ELEMENTS, N,P,K,CA AND MG IN THE LEAVES OF APRICOT CV HUNGARIAN BEST

The study of the contents and the seasonal changes of the major elements N,P,K,Ca and Mg in the leaves of apricot cv Hungarian Best, budded on seven plum cvs as interstocks (Belošljiva, Metlaš, Stanley, Kolenstockzwetsche, Wangenheims Frühzwetsche, Pozegaca and Kapavac) and on rootstock Prunus cerasifera var Myrobalan was carried out from 1977–1978. Special attention was given to the behaviour and effect of different interstocks on the leaves content of the mentioned major elements.

In the apricot leaves the nitrogen content was highest on interstock Kapavac (1,96%), phosphorus on Stanley (0,455%), potassium on Metlas (3,05%), calcium, (2,00%) and magnesium (0,474%) on Kolenstockzwetsche.

The seasonal absorption of nitrogen was the highest in May and decreasing from May to September; the phosphorus content decreased from May to June and increased from July to September; the potassium content in some groups of interstocks decreased from May to June and increased from July to August and decreased in September, and with other groups increased from May to August and decreased in September; the calcium and magnesium content increased from May to September.

The most convenient behavior and effect on the content of the major elements in the leaves of apricot and seasonal absorption were on plum cvs Kapavac, Belošljiva, Metlaš and Kolenstockzwetsche.