Effect of Nitrogen Fertilization and Microbial Prep arations on N min Content in Soil after Potato Harvesting

Abstract

A three-year field experiment was conducted under c onditions of Luvic Chernozem soil. Diversified nitrogen fertilization with 0, 60 , 120, and 180 kg N ha -1 , and microbial preparations improving soil properties were applied to potatoes, cv. ‘Satina’, cultivation. N–NO 3 concentration in the soil profile (0–0.9 m) in aut umn after potato harvesting fluctuated from 28 kg N ha -1 in the N 0 treatment to 70 kg N ha -1 in the N 180 treatment, whereas N–NH 4 content varied from 22 to 48 kg N ha -1 , respectively. The level of nitrogen fertilization also had a significant effect on the change in soil N–NO 3 content during the autumn-winter period. The decrease in N–NO 3 content in the N 0 treatments was 7% compared to 24% in the N 180 treatments. Application of microbial preparations to potato cultivation caused an increase in N min content in soil after crop harvesting. However, af ter the autumn-winter period, a lower amount of N–NO 3 , compared to the control treatment, was found in the treatments where microbial prepara tions had been used. Keywords: Ammonium nitrogen, Nitrate nitrogen, Loss of N–NO 3 , Solanum tuberosum .