Influence of fertigation on generative potential and pomological properties of different apple cultivars Uticaj fertirigacije na parametre generativnog potencijala i pomološke osobine različitih sorti jabuke

The paper presents an investigation into the influence of fertigation on generative potential parameters and pomological properties of apple fruits. The study was done in apple orchard of Fruit Research Institute Cacak (Serbia) over two-year period (2009– 2011) on three cultivars ('Morens Jonagored', 'Gloster' and 'Granny Smith'). Fertigation included fertilizers NPK 16:8:32, NPK 12:0:43 and PGPR – inoculum of diazotrophic bacterium Klebsiella. Results of the study suggest that fertigation with 12:0:43 NPK fertilizer had the most pronounced effect on all generative potential parameters, except abundance of flowering (initial fruit set – 3.71; final fruit set – 3.31). Similarly, this fertilizer had the same effect on all yield parameters in the apple cultivars studied, i.e. yield per tree – 9.60 kg/tree, yield per unit land area – 24.40 t/ha, cumulative yield – 19.20 kg/tree, cumulative yield 48.00 t/ha and yield efficiency – 0.77 kg/cm 2 . Mineral fertilizer NPK 16:8:32 gave the highest abundance of flowering (4.51). In terms of pomological properties the applied fertilizers had a significant effect on fruit weight (239.05 g), soluble solids content (14.78%) and ripeness degree (4.75).