Ebrahimi Farkhondeh, Edalat Mohsen, Naderi Ruhollah
Department of Plant Production and Genetics, School of Agriculture, Shiraz University, Shiraz, Iran.
PeerJ. 2025 Jul 31;13:e19592. doi: 10.7717/peerj.19592. eCollection 2025.
Climate change poses significant threats to wheat production, particularly in regions prone to increasing temperatures and water scarcity. This study aimed to explore the optimum planting date and irrigation schedule that increases winter wheat productivity under the potential adverse impacts of climate change.
A combination of data from 2-year field experiments (2018-2019 and 2019-2020) and simulation data of the Crop Environment Resource Synthesis (CERES)-Wheat model was employed in this research. The weather data emanating from eight global climate models (GCMs) of Climate Model Intercomparison Project 5 and 6 (CMIP5 and CMIP6) under Representative Concentration Pathways (RCP-4.5 and RCP-8.5) and Shared Socioeconomic Pathways (SSP-245 and SSP-585) were used to predict rainfall and temperature variations in two future periods (2041-2070 and 2071-2100).
The findings demonstrated that the annual maximum and minimum temperatures (T and T) would respectively increase by 3.14 °C and 3.50 °C in the 2050s, based on averaging all models of CMIP5 and CMIP6 with the highest T values projected for June to August. In the 2080s, further warming of 4.54 °C and 4.66 °C was anticipated in the annual T and T, again peaking in June to August, respectively. As opposed to the baseline period, precipitation over the growing season (October to May) is projected to be reduced by 23.03% and 29.48% in the 2050s and 2080s, respectively, with the lowest rainfall occurring in May. The anthesis date was projected to decline by 27, 37, 17, and 31 days under RCP-4.5, RCP-8.5, SSP-245, and SSP-585 scenarios, respectively. Additionally, the findings indicated that the period in which the wheat is grown decreased by 23, 32, 22, and 29 days under RCP-4.5, RCP-8.5, SSP-245, and SSP-585, respectively. Planting wheat from October 22 to November 11 recorded the highest value of grain yield in all irrigation treatments. On average, across all scenarios, with a 3-week early planting date compared to October 22, the grain yield was predicted to decrease by 22-44%. Therefore, adjusting the planting date and the irrigation time as the adaptation strategy during climate change slightly increased wheat grain yield in semi-desert regions like the Fars province. This advancement is linked to the crop's ability to utilize cooler temperatures during critical growth phases when sown earlier.
气候变化对小麦生产构成重大威胁，尤其是在气温上升和水资源短缺的地区。本研究旨在探索在气候变化潜在不利影响下提高冬小麦生产力的最佳播种日期和灌溉时间表。
本研究采用了2年田间试验（2018 - 2019年和2019 - 2020年）的数据以及作物环境资源综合（CERES）-小麦模型的模拟数据。使用了气候模式比较计划第5阶段和第6阶段（CMIP5和CMIP6）的8个全球气候模型在代表性浓度路径（RCP - 4.5和RCP - 8.5）以及共享社会经济路径（SSP - 245和SSP - 585）下的气象数据，来预测两个未来时期（2041 - 2070年和2071 - 2100年）的降雨和温度变化。
研究结果表明，基于对CMIP5和CMIP6所有模型的平均，6月至8月预计最高温度值下，2050年代年最高和最低温度（Tmax和Tmin）将分别上升3.14℃和3.50℃。在2080年代，预计年Tmax和Tmin将进一步升温4.54℃和4.66℃，同样分别在6月至8月达到峰值。与基准期相比，预计2050年代和2080年代生长季（10月至5月）的降水量将分别减少23.03%和29.48%，5月降雨量最低。在RCP - 4.5、RCP - 8.5、SSP - 245和SSP - 585情景下，预计开花期将分别提前27、37、17和31天。此外，研究结果表明，在RCP - 4.5、RCP - 8.5、SSP - 245和SSP - 585情景下，小麦种植期分别减少23、32、22和29天。在所有灌溉处理中，10月22日至11月11日种植小麦的籽粒产量最高。平均而言，在所有情景下，与10月22日相比提前3周播种，预计籽粒产量将下降22 - 44%。因此，在气候变化期间，将调整播种日期和灌溉时间作为适应策略，在法尔斯省这样的半干旱地区能略微提高小麦籽粒产量。这一增产与作物在较早播种时关键生长阶段利用较低温度的能力有关。
