Assessing vulnerability of wheat productivity to changing temperature through field experimentation and modeling approaches

Climate change has shifted the pattern of sowing under different environmental conditions. Wheat is very sensitive to high temperature. It is one of the most limiting factor of growth and grain yield of wheat. So, a field trial was conducted to assess vulnerability of wheat productivity to changing temperature through field experimentation and modeling approaches at Agronomic Research Area, University of Agriculture, Faisalabad in Rabi Season, 2014-2015. Four sowing dates starting from 15th November with 15 days interval were allocated in randomized complete block design (RCBD) under split plot arrangement in main plots while varieties (Punjab-2011, Galaxy-2013) in subplots. There were three replications. The results showed the maximum biological yield 11891 kg per ha, productive tillers 286.3 m-2, grains per spike 42.56, 1000-grain weight 43.14 g, grain yield 4314 kg per ha, and leaf area index (cm2/cm2) 5.3 were recorded in 1st sowing (15th November) of Galaxy-2013. The observed crop yield was compared with simulated one by using APSIM-Model (Agricultural Production Systems Simulator). The APSIM-Model was calibrated with phenology, yield and yield components of 1st sowing date (15th Nov.). Errors percentage for days to anthesis, maturity, maximum LAI, grain yield and biomass of Galaxy-2013 were 0.0,-1.36, -0.38, 0.0 and 2.91 during calibration. While in case of Punjab-2011 errors percentage for days to anthesis, maturity, maximum LAI, grain yield and biomass were 0.0, 0.70, -2.12, 0.48 and 0.22. APSIM- Wheat model was evaluated with the data recorded from the remaining three sowing dates. The average error between simulated and observed values for sowing dates were ranged from -6.47- to 9.48. It was concluded from the above study that the performance of wheat sown in 15th November, 2014 was the best yield (4314.08 kg per ha). APSIM- Wheat model performed better in semi-arid environment at early sowing dates. Model can be used for simulation of phenology, growth and yield of wheat in semi-arid conditions of Faisalabad.