Evaluation of CropSyst Model to Simulate the Effect of Irrigation and Nitrogen Levels on Clusterbean

Abstract

An experiment entitled “Evaluation of the CropSyst model to simulate the effect of irrigation and nitrogen levels on clusterbean” was carried out at village Bajju, Bikaner, Rajasthan during kharif season of 2016. The treatment comprising 3 levels of irrigation (100, 200 and 300 mm) and 4 levels of nitrogen (0, 20, 40 and 60 kg N/ha) comprising a total of 12 treatment combinations in split plot design with four replications. The simulation of CropSyst model was utilized to quantify and verify the interactive effect of different irrigation and nitrogen treatments on the productivity of clusterbean using measurements from field experiment. The soil of site are loamy sand having 86.3, 7.8 and 5.9 % of sand, silt and clay, respectively in 0-15 cm soil depth with pH 8.1 and low soil organic matter content (0.13%). The prediction of the model for seed yield and biomass was acceptable with 17.1 and 22.1 % of RMSE which may be considered good prediction by the model. However, the simulated N-uptake was over predicted by model and did not agreed with field measurements with 39.8% RMSE. The soil moisture content at different stages of growth was well simulated by CropSyst. The RMSE of moisture content ranged from 0.0123 to 0.0278 in clusterbean.