Abstract
The recent surge in interest in fruit growing without the use of agrochemicals in order to safeguard environmental and human health has led to increased awareness of organic fruit production (OFP). Despite the widespread use of the method, there is little information on its nutritional aspects, especially in Hungary. Therefore, the aim of this three-year study was to investigate the nutrient status in an organic apple management system and the impact of nutrient applications on nutrient uptake and on the environment. The research was undertaken at the orchard Fruit Research Station of the University of Debrecen in Debrecen-Pallag, Hungary, during 2009-2011. Three cultivars (’Reanda’, ’Rewena’, and ’Retina’) were selected for the study. In the plantation, only organic manure was applied (stable manure, 30 t ha-1, in 2007). The effect of organic methods was monitored by soil and leaf analyses, as well as field observations. Leaf analysis results indicated significantly lower N, K, Mn, Cu and Zn content in cultivar ‘Retina’ than in ‘Reanda’ and ‘Rewena’. Results suggested that mobility and availability were unbalanced and obstructed, especially in the case of Ca. The study also demonstrated that the lower nutrient content of soil and also the generally poorer uptake of Ca and Zn in organic apple orchards resulted in higher production risks as compared with conventional or integrated ones. We conclude that a more balanced and more efficient nutrient supply system is needed for organic farms in order to achieve good quality and profitable yield.