Mineral composition of high blueberry leaves and fruits depending on substrate type used for cultivation

Abstract

In 2004-2006, an experiment was established at the Experimental Station Rajkowo belonging to the Agricultural University (West Pomeranian University of Technology) in Szczecin. High blueberry bushes were planted in an alkaline reaction (pH 7.1) heavy soil using three different substrates. The bushes were planted in trenches filled with peat, cocoa husk and sawdust. The fertilization of the plants was limited to a sole nitrogen supply (30 kg N ha-1), because chemical analyses of both the soil and the substrates showed high and/or moderate content of other nutrients. In order to decrease cocoa husk reaction and to maintain the reaction of peat and sawdust, the bushes were irrigated with H 2 SO 4 acidified water up to pH 2.5-3.5. The bed prepared of cocoa husk was characterized by the highest N (23.8 mg 100 g -1 ), Zn content (51.6 mg kg -1 ), and pH (5.0). On the other hand, sawdust substrate had the lowest salinity (0.35 g NaCl kg-1). Sawdust substrate showed the highest level of Mn (56.5 mg kg-1) and Cu (7.4 mg kg-1) and the lowest of Ca (83 mg 100 g-1), whereas, peat substrate showed the highest salinity (0.87 g NaCl kg -1 ) and the lowest pH (3.8). The usage of cocoa husk substrate resulted in the highest content of N (23.6), K (6.9 g kg -1 ) and Mn (104.5 mg kg -1 ) in cv. Sierra blueberry leaves as well as N (16.0) and K (6.5 g kg -1 ) in berries. The plants grown in sawdust substrate showed the highest level of Ca (1.75 g kg-1), Cu (3.2) and Zn (12.4 mg kg -1 ), in the leaves as well as S (1.7) and Cu (3.5 mg kg -1 )