Evaluation of Potato Yield and Nitrate Accumulation in Potatoes Cultivated under Differentiated NPK Fertilization Conditions

Potato is a plant with high nutrient requirements but demands a balanced fertilizer management. Because in potato crop the application of high nitrogen levels may result in a decrease in the tubers quality with implications for human health, the aim of this paper was to study the potato yield, tuber starch content and the nutritional quality of two potato varieties fertilizated with different levels of nitrogen and different NPK ratios and to find the best fertilization variants to obtain the highest yield and quality for potato tubers with reduced implications for the accumulation in the environment. Evaluation of nitrates and nitrites potato tubers content was performed on the material obtained in a polyfactorial experiment with different NPK ratios (1:1:1 and 1:0.9:2) and different doses of nitrogen (100 and 200 kg N/ha) and two different potato varieties (Christian and Roclas). The experiment was conducted within the N.I.R.D.P.S.B. Braşov experimental field, on a chernozem soil and according with the current fertilization practices in the region, under non irrigated conditions. The experiment results show that the higher NPK ratio and nitrogen dose of 200 kg N/ha determined reduction of tubers starch content and significant increases in tuber nitrates and nitrites contents at high nitrogen doses (200 kg N/ha).