Predicting the response of a potato-grain production system to climate change for a humid continental climate using DSSAT

Abstract

Climate change presents both challenges and opportunities for crop production. This study evaluated the vulnerability of potato (Solanum tuberosum L.) and barley (Hordeum vulgare L.) to climate change for 2050 to 2079 in Maine, U.S.A., and the potential of changing variety and planting date as climate adaptation strategies. The DSSAT model v4.7 was calibrated and evaluated for contrasting varieties of potato (Atlantic, a mid-season variety, and Russet Burbank, a late-season variety) and barley (Robust, a 6-row feed variety, and Newdale, a 2-row malting variety) using 99 field experiments conducted in Maine. The model accurately simulated observed final yield for each variety with modeling efficiencies (EF) ranging from 0.60 to 0.84 and coefficients of determination (r2) above 0.98. Climate change simulations compared crop yield across multiple planting dates for one baseline period (1989-2018) and four future climate scenarios (two emissions scenarios, RCP 6.0 and 8.5, with and without elevated CO2). In the absence of elevated CO2, yield of the potato variety Atlantic, and both barley varieties declined by 6 to 27% under elevated temperature and precipitation, but increased by 5% for the potato variety Russet Burbank. However, under future climate conditions and elevated CO2, yield of all potato and barley varieties increased or were unchanged. Optimal planting date for each variety was consistent across climate scenarios. These results suggest that climate change may favor longer-season varieties such as Russet Burbank, but adjusting planting date may not be an effective climate change adaptation strategy in this region. Elevated CO2 boosted crop growth and development across all varieties for a humid continental climate and for the time period studied. The models used do not address climate change's possible effects on crop quality or losses due to plant diseases and pests.