Optimization of fertilization for improved nitrogen management in irrigated pear (Pyrus communis ‘Conference’) production in Belgium

Over the past years irrigation has become common practice in pear growing (Pyrus communis L. 'Conference') in Belgium and the Netherlands. The presence of an irrigation installation allows pear growers to fertigate by dissolving fertilizers in the irrigation water which increases nutrient uptake efficiency. In an experiment in 'Conference' pear, yield and fruit quality response to different doses of N fertilization was studied. We tested whether optimal pear production was possible applying only 60 kg N (40% reduction) through a combination of broad band fertilization with Calcium Ammonium Nitrate (CAN) and calcium nitrate. These approaches were compared with the Growers practice, which means 95 kg N fertilization through a combination of organic manure, CAN and Calcium nitrate. A 20% reduced N fertilization scheme of 75 kg N consisting of organic manure and CAN was also included in the trial. The experimental orchard was irrigated using a regulated deficit irrigation scheme scheduled using a soil water balance. Sentinel-2 satellite images were used to study variability in canopy size throughout the orchard. Yield results and soil analysis indicated that fertilization with 60 kg N, partly applied by fertigation, is sufficient to gain maximal yield in the experimental orchard.