The Effect of Nitrogen Dosage on N Efficiency and Protein Content in Potatoes

Abstract

The availability of nutrients in the soil, especially nitrogen (N), significantly affects the production and quality of potato tubers. Case N is a very dynamic nutrient. Uncontrolled application of N fertilizer causes low farm efficiency and even results in environmental pollution. This study aims to analyze N fertilizer use's efficiency and analyze the optimum dose that can increase the protein content of potato tubers. Field trials were carried out on farmers' land in the village of Sumberejo, Batu, East Java, Indonesia, at an altitude of 710 above sea level. The study used a randomized block design with four N dosage treatments, namely: 40, 80, 120, 160 N kg ha-1 . The treatment was repeated six times, with each replication consisting of 5 plant samples. N fertilizer source comes from ZA, which is applied two times, at the time of planting and on the 35th day after planting. The results showed that N fertilizer's application at various doses had a significant effect on N nutrient efficiency and protein content in potato tubers. Giving a dose of N of 120 kg ha-1 showed the highest yields on dry canopy weight, N in the canopy, chlorophyll, and tuber protein at harvest. The minimal nitrogen use efficiency (NUE) was achieved at a dose of 151.84 N kg ha-1 . The optimum dose of tuber mineral content was achieved at 138.56 N kg ha-1 , namely 5.40%.