Forecasting of Rainfed Wheat Yield in Pothwar Using Landsat 8 Satellite Imagery and DSSAT

Abstract

Drought leads to serious reduction in the yield of wheat in rainfed regions, which is a growing environmental phenomenon faced by wheat crop. The effect of drought stress during grain filling on yield and some physiological traits of wheat confirms that post-anthesis drought significantly reduces photosynthesis rate and grain yield. We tested the DSSAT (Decision Support System for Agrotechnology Transfer) CERES-Wheat model with details of field experimental data having different sowing dates, and their effect on yield and result were compared with the maps obtained by the Landsat 8 satellite imagery using ERDAS. ERDAS IMAGINE is an easy-to-use, raster-based software designed specifically to extract information from images. The field trial was carried out at Islamabad and the University Research Farm (URF)-Koont, Chakwal Road. Field survey was also carried out in rainfed region to collect field data from farmers, and Landsat imagery was downloaded from the EarthExplorer USGS website. Yield simulated from DSSAT (Decision Support System for Agrotechnology Transfer) was compared with the maps obtained from Landsat 8 satellite imagery using ERDAS. Simulated grain yields during 2017–2018 have close association with observed data for different sowing date experiments. At Islamabad maximum grain yield (3263 kg/ha) was observed for Sd2 (sowing date two), while minimum (1126.66 kg/ha) was recorded for Sd5 (sowing date five). At URF-Koont, maximum grain yield (3024 kg/ha) was observed for Sd2 (sowing date two), whereas minimum (1058.33 kg/ha) was recorded for Sd5 (sowing date five). Simulated harvest index showed close association with observed data for different treatments during 2017–2018. Higher harvest index (35%) was observed for Sd2 (sowing date two, 15 November), while minimum (28%) was recorded for Sd5 (sowing date five, 30 December). At URF-Koont, maximum grain yield (35%) was observed for Sd2 (15 November), whereas minimum (28%) was recorded for Sd5 (30 December).