Influence Of Different Nitrogen Fertilization Rates On The Qualitative Performance Of Three Peach Cultivars

Producing peach fruits (Prunus persica L) of high quality and with high nutritional value involves selecting the right cultivar and the optimum application of inputs during growing. This study evaluated the effects of using different concentrations of nitrogen fertilizer (60%, 80% and 100%) on the qualitative and nutritional performance of three different peach cultivars (Slapi, Romestar and Tardibelle) grown in the Marche region of Italy. It was found that peach cultivar strongly affected the qualitative parameters: for example, Slapi had the lowest significant average fruit firmness value (2.67 kg) as opposed to 4.99 kg in Romestar and 5.30 kg in Tardibelle. For the nutritional parameters, Romestar recorded the highest average values for both total antioxidant capacity (TAC) and total phenolic content (TPH), 8.38 mmol trolox eq/kg and 1216 mg GA/kg respectively, while Tardibelle recorded the lowest values (7.27 mmol trolox eq/kg and 1084 mg GA/kg, respectively). The qualitative parameters were less influenced by the nitrogen fertilization treatments. For the nutritional parameters, 80% treatment in Romestar cultivar recorded highest values in both fruit TAC and TPH (9.17 mmol Trolox eq/Kg fruit and 1268 mg GA/Kg fruit respectively), while 80% treatment of Tardibelle recorded the lowest fruit TAC and TPH (5.90 mmol Trolox eq/Kg fruit and 1025 mg GA/Kg fruit respectively). The findings derived from this study will help growers to select the most suitable combination of cultivar and fertilization treatment, to obtain the desired qualitative goals. Keywords: Prunus persica, peach cultivar, nitrogen fertilization, fruit quality, antioxidant capacity, total phenolic content