Nutrients dynamics in Komatsuna (Brassica campestris L.) growing soil fertilized with biogas slurry and chemical fertilizer using 15N isotope dilution method

Abstract

Efficient liquid slurry land application requires knowledge of nutrient content, proper application rate and crop needs. An improved understanding of the cycling of biogas slurry N is a prerequisite for making better use of this N source. The efficiency of nitrogen (N) derived from biogas slurry must be determined to optimize use of N and reduce impact on the environment. Keeping in view, a pot experiment was initiated to estimate crop N uptake from biogas slurry and chemical fertilizer that applied to Komatsuna (Brassica campestris L.) using 15N isotope dilution method. In this experiment 180 kg N ha-1 of 1.0 atom % 15N excess ammonium chloride was used. Nitrogen derived from biogas slurry (Ndfs) and recovered-N (N rfs) in Komatsuna was measured to know the effects of applied slurry on the performance of the crop and nutrient dynamics in a Brown Lowland Soil, Fluvisols west Japan. It was found out that 15N uptake was slightly higher in chemical fertilizer compared to slurry application. In addition, N uptake derived from chemical fertilizer (Ndfc) was better than that taken from soil (Ndfs). Fertilizer use efficiency (FUE- 15N) was lower in slurry treatment (47.2%) than chemical fertilizer (65.9%). The relative efficiency (slurry use efficiency/chemical use efficiency *100) was varied in Komatsuna roots and leaves. © 2006 Asian Network for Scientific Information.