STUDY ON THE MACRONUTRIENT CONTENT OF APPLE LEAVES IN AN ORGANIC APPLE ORCHARD
2006, 7 (2) p. 329-336
Macronutrient contents of soil and apple leaves were investigated in an organic apple orchard in Eastern Hungary in 2002-2004. Soil samples were taken from 0-20 cm depth in April and October. The macronutrient content of leaves was measured on cvs. Jonagold, Mutsu, Idared, Red Elstar, Egri Piros, Reka, and Remo at six assessment dates (from April to September). The macronutrient contents of N, P, K, S, Ca and Mg were measured in both soil and leaf samples, then macronutrient ratios were calculated from the obtained results. The results showed that younger leaves contained more N and P than older ones. K and Ca contents of leaves decreased until July, then increased slightly, and decreased again. A continuous decrease of the S content of leaves was observed until August. The Mg content of leaves increased until June, then decreased in July and then increased again. Macronutrient values were dependent on cultivar. Calculated macronutrient ratios showed that the nutrient supply of soil was not optimal in the orchard.