Calibration and validation of DSSAT 4.5 model for wheat in North-West Bihar

Abstract

Wheat (Triticum aestivum L.) is a very important irrigated rabi crop in Bihar with 2.25 Mha area, 5.21 Mton of production and the average productivity of about 2328 kgha-1. Fluctuating temperatures and terminal heat load during its growth period interfere with normal growth and productivity potential of the crop. In this backdrop, the present investigation was conducted at Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur (25.980 N, 85.670 E, 52 m amsl) to calibrate and validate the DSSAT 4.5 crop simulation model for wheat. For this purpose, field experiments were conducted during rabi seasons of 2010-11 and 2011-12 with five dates of sowing viz. 15th November, 25th November, 5th December, 15th December and 25th December using two popular cultivars, HD 2824 and HD 2733. The days to anthesis and maturity, leaf area index, above ground biomass production and grain yield as simulated by the model were validated with observed data. Results revealed that the model estimated the days to anthesis and maturity for both the cultivars closely with observed data. Test criteria calculated for the two cultivars suggested that the model performance was better for HD 2733 than for HD 2824. The model satisfactorily simulated the phenology and yield of wheat cultivars and hence it can be used in undertaking suitable management practices and yield prediction under changing climatic condition in Bihar.