Yield is a complex trait reflecting the interaction between genotype, environment and farm management. The challenge of adapting spring crops to climate change involves unravelling the contribution of climatic factors that impact yield performance according to phenological stages. The aim of the present study was to identify the main Environmental Covariates (EC) – climatic variables calculated over phenological stages – driving spring barley yield levels. Five contrasting European agro-climatic (AC) regions were defined as follows: United Kingdom and Ireland (UK-IE), Denmark and Sweden (DK-SE), France (FR), Northeast Germany, Czech Republic and Poland (N.E. DE-CZ-PL) and South Germany and Austria (S. DE-AT). Yield data from 270 two-row spring barley accessions/varieties, grown in 125 environments between 2015 and 2021, were collected from a multi-environment trials network. Using the phenology-calibrated CERES-Barley model (DSSAT), 91 ECs were calculated in each environment based on collected weather data and simulated phenological stages. Partial Least Squares (PLS) regression analyses were carried out to sort out the main ECs impacting yield performance in each of the five AC regions. Results showed that elevated temperatures and solar radiation were the main yield-drivers in all AC regions. Associations between water availability and yield were detected in most AC regions. The strongest contrasts were observed for the critical phenological stages during pre-anthesis, which govern grain number per unit area. Cool temperatures (days with minimum temperature <0°C or <7°C and average temperature <15°C) during emergence and tillering, and solar radiation intensity between emergence and grain filling, were the most yield contributing ECs. This study showed the importance of considering climate during early stages to predict yields. The identification of major yields EC drivers suggests the need to adjust agricultural practices in spring barley production across Europe for climate adaptation. This study unraveled the complexity of yield ecophysiology affecting spring barley in Europe. In order to improve the adaptation of spring barley to climate change, the perspective is to examine the role of ECs on genotype x environment interactions for yield and develop stable cultivars that outperform existing germplasm.

中文翻译：

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揭示影响整个欧洲春大麦产量的关键气候因素和物候阶段


产量是一个复杂的性状，反映了基因型、环境和农场管理之间的相互作用。使春季作物适应气候变化的挑战包括根据物候阶段揭示影响产量表现的气候因素的贡献。本研究的目的是确定影响春大麦产量水平的主要环境协变量 （EC） – 在物候阶段计算的气候变量。五个截然不同的欧洲农业气候 （AC） 区域定义如下：英国和爱尔兰 （UK-IE）、丹麦和瑞典 （DK-SE）、法国 （FR）、德国东北部、捷克共和国和波兰 （N.E. DE-CZ-PL） 以及南德和奥地利 （S. DE-AT）。从多环境试验网络收集了 2015 年至 2021 年间在 125 个环境中生长的 270 个双行春大麦种质/品种的产量数据。使用物候校准的 CERES-Barley 模型 （DSSAT），根据收集的天气数据和模拟物候阶段，在每个环境中计算了 91 个 EC。进行偏最小二乘法 （PLS） 回归分析，以梳理影响 5 个 AC 区域每个区域产量表现的主要 EC。结果表明，高温和太阳辐射是所有 AC 地区的主要产量驱动因素。在大多数 AC 地区检测到水的可用性与产量之间的关联。在花前的关键物候阶段观察到最强的对比，这些阶段控制着每单位面积的粒数。出苗和分蘖期间的低温（最低温度 <0°C 或 <7°C 和平均温度 <15°C 的天数）以及出苗和灌浆之间的太阳辐射强度是产量贡献最大的 ECS。 这项研究表明了在早期阶段考虑气候以预测产量的重要性。确定主要产量 EC 驱动因素表明，需要调整整个欧洲春大麦生产的农业实践以适应气候。这项研究揭示了影响欧洲春大麦的产量生态生理学的复杂性。为了提高春大麦对气候变化的适应能力，研究目标是研究 ECs 对基因型 x 环境相互作用的影响，并开发优于现有种质的稳定品种。