A better comprehension and analysis of climate impacts on crop traits allows the implementation of more appropriate adaptation strategies and, therefore, a higher resilience of the future cropping systems. The aims of this study were: (i) to assess how the climate changed in the last 32 years in a Mediterranean‐type climate, (ii) to understand how crop traits evolved over time in early and late durum wheat cultivars and (iii) to highlight which weather variables mostly affected the performances of diverse durum wheat varieties. To investigate this, a 32‐year period (i.e., 1989–2020) was analysed, detecting possible significant trends of weather variables (e.g., air temperatures, precipitations, solar radiation) and crop traits (e.g., earliness, yield, yield components and test weight) over time in Viterbo, central Italy. Eight durum wheat varieties (4 early and 4 late cultivars) were chosen from the most used in that location. A clear upward trend of the monthly maximum air temperature during the entire growing season was revealed (0.12°C–0.21°C per year), while rainfall displayed a significant trend only for February and March. Days to heading and number of spikes per unit area showed a significant downward trend moving towards 2020. Anticipation of heading date was much more pronounced in the late cultivars than in the early ones, so that the difference between the two groups was reduced from about 10 days of 1989 to less than 6 days of 2020. Grain yield stagnated around 5 t ha−1 with late varieties that proved to be as good producers as the early ones. Test weight and thousand kernel weight showed a slight increase over time. Maximum temperatures of February and March exerted a considerable influence in reducing time to heading (0.7–3.4 days for each additional°C), while the maximum temperature of May was detrimental for grain yield (−180 to −270 kg ha−1 for each additional °C). Our study identified two weak points in the current durum wheat cultivation: (i) phenology is being more and more similar among modern cultivars; (ii) the number of spikes per unit area dramatically decreased in the last 30 years. Therefore, beside greater genetic diversity, a new agronomic approach, especially from seeding to the end of the tillering stage, will be required to cope with durum cultivation in the future climate scenario of the Mediterranean. The outputs of our analysis add precious information on the comprehension of climate change effects on Mediterranean cropping systems and can guide either the decision making for the management of durum wheat or its breeding activity for the future.

中文翻译：

---

地中海环境中硬粒小麦品种对气候变化的响应：21 世纪之交天气和作物变量的趋势


更好地理解和分析气候对作物性状的影响，可以实施更合适的适应策略，从而提高未来种植系统的弹性。本研究的目的是：（i） 评估过去 32 年地中海型气候中的气候如何变化，（ii） 了解早熟和晚熟硬粒小麦品种的作物性状如何随时间演变，以及 （iii） 强调哪些天气变量对不同硬粒小麦品种的表现影响最大。为了调查这一点，分析了 32 年期间（即 1989-2020 年），检测了意大利中部维泰博的天气变量（例如气温、降水、太阳辐射）和作物性状（例如早熟、产量、产量成分和测试重量）随时间推移的可能重要趋势。从该地区最常用的品种中选择了 8 个硬粒小麦品种（4 个早熟品种和 4 个晚熟品种）。整个生长季的月最高气温呈明显的上升趋势（每年 0.12°C–0.21°C），而降雨量仅在 2 月和 3 月表现出显著的趋势。到 2020 年，抽穗天数和每单位面积的尖峰数量呈显著下降趋势。晚熟品种对抽穗日期的预期比早熟品种要明显得多，因此两组之间的差异从 1989 年的约 10 天减少到 2020 年的不到 6 天。谷物产量停滞在 5 t ha-1 左右，晚熟品种被证明与早期品种一样好。测试重量和千粒重量显示随着时间的推移略有增加。2 月和 3 月的最高温度对缩短抽穗时间 （0.7-3.每增加 4 °C），而 5 月的最高温度对粮食产量不利（每增加 °C ，-180 至 -270 公斤公顷-1）。我们的研究确定了当前硬粒小麦种植的两个弱点：（i） 现代品种之间的物候越来越相似;（ii） 在过去 30 年中，每单位面积的尖峰数量急剧减少。因此，除了更大的遗传多样性外，还需要一种新的农艺方法，特别是从播种到分蘖阶段结束，以应对地中海未来气候情景下的硬粒小麦种植。我们的分析结果为理解气候变化对地中海种植系统的影响增加了宝贵的信息，可以指导硬粒小麦管理或其未来育种活动的决策。