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.

气候变化给作物生产带来了挑战和机遇。本研究评估了马铃薯(Solanum tuberosum L. )和大麦 ( Hordeum vulgareL.) 2050 年至 2079 年美国缅因州的气候变化，以及改变品种和种植日期作为气候适应策略的潜力。DSSAT 模型 v4.7 已针对马铃薯（Atlantic，中季品种，Russet Burbank，晚季品种）和大麦（Robust，6 行饲料品种，Newdale，a 2 行麦芽品种）使用在缅因州进行的 99 次田间试验。该模型准确模拟了每个品种观察到的最终产量，建模效率 (EF) 范围从 0.60 到 0.84，决定系数 (r ²) 高于 0.98。气候变化模拟比较了一个基线期（1989-2018 年）和四种未来气候情景（两种排放情景，RCP 6.0 和 8.5，有和没有升高的 CO ₂）的多个种植日期的作物产量。在没有 CO ₂升高的情况下，马铃薯品种 Atlantic 和两个大麦品种的产量在升高的温度和降水下下降了 6% 到 27%，但马铃薯品种 Russet Burbank 的产量增加了 5%。然而，在未来的气候条件和 CO ₂升高的情况下，所有马铃薯和大麦品种的产量增加或保持不变。每个品种的最佳种植日期在不同气候情景下是一致的。这些结果表明，气候变化可能有利于 Russet Burbank 等季节较长的品种，但调整种植日期可能不是该地区有效的气候变化适应策略。在潮湿的大陆性气候和研究的时间段内，升高的 CO ₂促进了所有品种的作物生长和发育。所使用的模型并未解决气候变化对作物质量或因病虫害造成的损失的可能影响。