Using the nitrification inhibitor DMPP to enhance uptake efficiency in a fertigated peach orchard plantation

A three year experiment from 2014 to 2016 was conducted to assess the effect of a nitrification inhibitor (NI) DMPP, and nitrogen (N) application rates in a commercial peach orchard (889 trees ha(-1)) in a drip irrigated calcareous soil in the Ebro Valley (Lleida, Spain). The mineral content of leaves and fruits, vegetative growth and total yield were monitored each year. A significant effect of NI was observed. Increasing N application rates and the use of NI increased the tree canopy area and N content of the leaves and fruits. The use of NI could be an effective way to minimize the use of fertilizers in orchard systems, reducing the environmental impact. Yield was affected by the N dose and timing of application. The highest yield (58.6 t ha(-1) with a fruit diameter higher than 65 mm) was recorded in 2015, applying only 50 kg N ha(-1) plus NI, in fruit growth phase I. no negative visual effects were observed in the field except for trees with lower N doses (25 kg N ha(-1)). Darker leaves were visually observed in the NI treatments. More experiments need to be established to corroborate these findings.