Crop simulation in groundnut (Arachis hypogaea L.) using DSSAT-CROPGRO model

Abstract

The field work was conducted at Instructional Farm, Vellanikkara by adopting split plot design with five replications. Variety used in the experiment was TNAU CO-6. Four dates of sowing such as November 1st, November 15th, December 1st and December 15th were used as main plot treatments and three irrigation levels of IW/CPE ratio 0.6, 0.8 and 1.0 were used as sub plot treatments.

The November 1st planting was produced significantly higher yield compared to the November 15th, December 1st and December 15th planting. All the growth characters like plant height, number of leaves and dry matter accumulation were found to be highest during November 1st planting. Shelling percentage and harvest index recorded during November 1st planting was on par with December 1st planting. Among the three irrigation treatments plant height, number of leaves, yield, shelling percentage and harvest index were found to be higher in IW/CPE ratio 1.0. Number of days taken to reach each phenophases were different under each dates of planting. Maximum duration was recorded during December 1st planting and minimum duration was recorded during November 1st planting. Crop weather relationship studies suggested that maximum temperature and bright sunshine hours recorded during pegging to pod formation period showed a negative influence on yield and phenology. Only rainfall during this period showed a positive influence on yield. The efficiency of every crop model depends on how accurately the genetic coefficients were calibrated. The genetic coefficients for DSSAT-CROPGRO Peanut model were calibrated for the variety TNAU CO-6 using the data sets generated during the field experiment. The goodness of fit between observed and simulated values were evaluated using root mean square error and d- stat index. The simulated value of yield, yield attributes and phenology of groundnut crop using DSSAT-CROPGRO Peanut model was in good agreement with observed value.