Effect of irrigation regimes and nitrogen levels on nitrogen uptake and soil chemical properties after growing ryegrass

Abstract

A field experiment was carried out at the Instructional-cum-Research (ICR) Farm, Assam Agricultural University, Jorhat. The experiment was laid out in split-plot design with three replications. The treatments consisted of five levels of irrigation in main plot viz., I0: Rainfed, I1: Irrigation at critical growth stages, I2: Irrigation at IW: CPE ratio of 1.0, I3: Irrigation at IW: CPE ratio of 1.2 and I4: Irrigation at IW: CPE ratio of 1.4 along with four levels of N - N0: 0 kg N/ha, N1: 30 kg N/ha, N2: 60kg N/ha and N3: 90 kg N/ha in sub- plots. The soil of the experimental site was sandy loam in texture, acidic in reaction, medium in organic carbon, medium in available N, available P2O5 and low in available K2O. The results revealed that higher values of nitrogen uptake was found in irrigation at IW: CPE ratio of 1.4. The treatment receiving nitrogen levels 90 kg/ha recorded higher values of nitrogen uptake. The effect of irrigation regimes on available N, P2O5 and K2O content in soil were found to be non-significant after harvest of ryegrass. The available N content in soil was found significant due to the effect of nitrogen levels but available P2O5 and K2O content in soil were found non-significant.