The role of biofertilizers in improving vegetative growth, yield and fruit quality of apple

Abstract

Apple trees which grafted on M.M. 106 stocks were planted at the beginning of spring 2014 in pots at the Research Institute of Horticulture in Skierniewice, Poland. The used treatments in the experiment were: NPK fertilization and bioproducts: Fertigo (Manure), Micosat, Humus UP, Humus Active + Aktywit PM, BioFeed Quality, BioFeed Amin, Vinassa, Florovit Natura and Florovit Eko. In the spring, these treatments were applied to apple trees alone or enriched with Pantoea sp., Pseudomonas fluorescens, Klebsiella oxytoca and Rhizobium sp. bacterial strains. Growth, yield and fruit quality parameters were evaluated. The results revealed that photosynthetic rate was greatly improved by the addition of bacteria to Fertigo (Manure), Micosat, Humus UP and Humus Active + Aktywit PM as compared to NPK. Tree trunk thickness was significantly enhanced with Vinassa, Florovit Natura and Florovit Eko enriched with bacteria. The application of bacterial strains increased the effectiveness of Fertigo (Manure), Humus UP, Humus Active + Aktywit PM, Biofeed Amin and Yeast in increasing significantly number and weight of fruits as compared to NPK.