Zeolite influences on nitrate leaching, nitrogen-use efficiency, yield and yield components of canola in sandy soil.

摘要

With regard to the low cation-exchange capacity and large saturated hydraulic conductivity of sandy soils, a field experiment was carried out in 2006-2007 to determine the impact of zeolite on nitrogen leaching and canola production. Four nitrogen (N) rates (0, 90, 180, and 270 kg ha-1) and three zeolite amounts (3, 6 and 9 t ha-1) were included as treatments. The results demonstrated that the highest growth parameters and seed yield were attained with 270 kg N ha-1 and 9 t zeolite ha-1. However, the highest and the lowest seed protein percentage and oil content were obtained with 270 kg N ha-1 accompanied by 9 t zeolite ha-1, respectively. Nitrate concentration in drained water was affected by nitrogen and zeolite. The lowest and highest leached nitrate values were found in control without N and zeolite (N₀Z₀) and in treatments with the highest N supply without zeolite (N₂₇₀Z₀), respectively. In general, nitrogen-use efficiency decreased with an increase in N supply. Application of 9 t zeolite ha-1 showed higher nitrogen use efficiency than other zeolite amounts. Also, application of more N fertilizer in soil reduced nitrogen uptake efficiency. In total, application of 270 kg N ha-1 and 9 t zeolite ha-1 could be suggested as superior treatment.