Response of CERES-wheat and CROPGRO-urd model (DSSAT model v 4.5) for tarai region of Uttarakhand

The study aimed response of CERES-wheat and CROPGRO-urd model for tarai region of Uttarakhand. Field experiments were conducted at N. E. Borlaug, Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during rabi and kharif seasons 2007 and 2008. CERES-wheat and CROPGRO-urd models version v 4.5 were used in this study. Cultivar specific genotypic coefficients were derived for wheat and urd during calibration. Model validation based on several independent sets of growth and yield data, including different nitrogen and irrigation levels. For all parameters t-test was found non-significant (‘t’ calculated values were smaller than t tabulated values at 5% level of significance), indicating that there were least differences between observed and predicted values. The result obtained with the model demonstrated satisfactorily prediction of phenology, growth and yield and thus it can be used for the prediction of wheat and urd growth as well as yield in this region

Sensitivity Analysis of CERES-Wheat Model under Hisar Conditions

The field experiment was conducted at Research Farm, Dept of Agricultural Meteorology, CCS HAU, Hisar (Lat.: 290 10’ N, Log.: 75036’ E & 215.2 m above msl), Haryana, India during the rabi season of 2014-15 and 2015-16. Experimental designed laid out with strip plot, as main plot treatment: four growing environments i.e. D1: 5th Nov., D2: 20th Nov., D3: 5th Dec. and D4: 20th Dec. and sub-plot treatment: four irrigation regimes, it applied at different phenophases (I1-CRI, I2- CRI and heading, I3- CRI+ jointing and milking, I4- CRI+ jointing + anthesis and dough stage). Crop growth and yield data of 2014-15 were used for calibration of DSSAT model and cultivar coefficients for WH1105 based on the observed crop characteristics. Genetic coefficient parameters are in the ranges obtained by the few other studies conducted on wheat with the exception of parameters G1, G2, and G3, related to grain growth. Sensitivity of simulated grain yield to down scaled sunshine hours, solar radiation -0.5 to -2.5 hours and -1°C to -5 MJ-2 day-1 showed a gradual decrease in grain yield, respectively.

Greengram Based Cropping Sequence for Sustainability under Changing Climate in Semi-arid Part of Karnataka, India

Background: Greengram based cropping sequences are followed in semi-arid parts of Karnataka, India. But, due to increasingly erratic and changing monsoon patterns under current climates the sustainability and profitability of these sequences are becoming more uncertain. Hence, a modeling study using seasonal analysis tool of DSSAT model was taken up to identify the most reliable sequence.Methods: Field experiments were carried out from 2015-2018 to calibrate and validate DSSAT model for four crop cultivars (greengram, chickpea, wheat and sorghum) under rainfed condition on deep black soils and then Sequential Analysis Tool of DSSAT model was run for 32 years (1985-2016) for three cropping sequences i.e., greengram-sorghum, greengram-wheat and greengram-chickpea. The simulated output analysis was done using yield, number of years crop failed during different seasons and the B:C ratio of each sequence. Result: Out of 32 years greengram crop, grown during kharif, failed only once whereas, during rabi season wheat, sorghum and chickpea failed seven, six and five years, respectively. Greengram-chickpea sequence recorded the highest B:C ratio (2.38) followed by greengram-sorghum (2.25) and greengram-wheat (1.76). Considering chances of crop failure and B:C ratio greengram-chickpea sequence was found to be the most reliable and remunerative system under rainfed condition of Karnataka during current climate.