Climate change adversely impacts crop production and imposes a wide range of constraints on agricultural systems especially in water-limited environments. Management strategies to enhance adaptation capacity are needed to mitigate climate change effects. The objective of this study was to investigate the potential of changing planting dates and planting densities as adaptation strategies to climate change for irrigated and rainfed wheat for possible enhancement of crop yield, harvest index and water use efficiency at three locations in northeast of Iran (Mashhad, Sabzevar and Torbat-h). For this purpose, the out- puts of five global climate models under RCP-4.5 and RCP-8.5 emission scenarios during three time periods (i.e., the 2020, 2050 and 2080) downscaled by MarkSimGCM were used to run the CSM-CERES-Wheat (v4.6) model. The results indicated that crop production will be reduced as affected by climate change based on prevailing and two other planting dates and planting densities in the future climate change, under all scenarios and years. In general, later planting dates with planting density of 400 plants m−2 caused higher produc- tion which leads to less yield reduction by about 8, 11 and 10% for irrigated wheat and 27, 21 and 26% for rainfed wheat on average across all periods and scenarios compared to cur- rent management practices in Mashhad, Sabzevar and Torbat-h, respectively. Based on this study, it seems that changing planting dates and densities can be beneficial for adaptation of wheat to climate change.

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