Potential climate change adaptation strategies for winter wheat production in the Texas High Plains

Winter wheat is one of the major crops in the Texas High Plains (THP) region, which is facing challenges from climate change (CC) and exhausting irrigation water supplies from the Ogallala Aquifer. The goal of this study was to assess the impacts of CC on winter wheat production in the THP and evaluate potential adaptation strategies using the Decision Support System for Agrotechnology Transfer (DSSAT) CERES-Wheat model. A thorough calibration of the model against field data resulted in a satisfactory simulation of phenology, leaf area index, grain yield (percent error, |PE| < 4.7%), biomass (|PE| < 7.1%), and evapotranspiration (|PE| < 11.9%). The evaluated model was then used for: (i) predicting winter wheat yield and irrigation water use, and (ii) evaluating six potential winter wheat cultivars under CC at three sites in the THP. Mixed trends were found for irrigated yield in the future across the study sites due to differences in climate and soils. Irrigation water use of winter wheat is expected to decrease in the future due to improved water use efficiency at elevated atmospheric CO2 concentration and reduced growing season length due to temperature rise. Dryland yield is expected to increase due to improved crop water use efficiency. Among the virtual cultivars tested for CC adaptation, increasing potential number of grains and vigorous root system were found to be the most desirable traits, since these cultivars had higher yield and lower or comparable irrigation water use than the reference cultivar. Long-maturity and stay-green cultivars were found to be not advisable due to significantly higher irrigation water use than the reference cultivar. Overall, the results showed that winter wheat production in the THP could benefit from CC under milder climatic conditions (mean growing season temperature < 13 degrees C). Enhancing yield potential traits and root architecture should be considered for screening cultivars for CC adaptation.