欧亚国际

摘要 

小麦产量的年际和局部波动主要可由非生物限制因素解释。热浪和干旱是最主要的胁迫源，通常会同时发生，随着全球气候变化，热浪和干旱的频率也在增加。在控制水分亏缺和高温条件下，对高通量方法进行了优化，以确定具有适应性应激反应的表型性状。10个基因型的小麦植株在25/18ºC昼夜条件下的全自动种植设施中种植30天，然后温度升高7天（38/31ºC昼夜），同时保持一半植株灌溉良好，一半植株田间持水量为30%。每天记录两次热图像、多光谱图像和花盆重。实验结束时，对碳水化合物和抗氧化剂代谢的关键代谢物和酶活性进行了量化。利用图像提取的参数成功地建立了回归机器学习模型来预测植物生物量。在持续监测逆境适应时，蒸散性状表现出显著的基因型-环境交互作用（GxE）。因此，在水分亏缺和高温条件下，蒸腾效率对于维持小麦节水策略和生物产量之间的平衡至关重要。应激耐受包括碳水化合物代谢的变化，尤其是糖酵解和糖酵解途径的变化，以及抗氧化代谢的变化。所观察到的对高温和水分亏缺敏感度的遗传差异可以在育种项目中加以利用，以提高小麦对气候变化的适应能力。

关键词： 

碳水化合物代谢、气候变化、抗旱性、粮食安全、高温、高通量植物表型、多光谱成像、普通小麦、缺水、小麦

High-throughput phenotyping of physiological traits for wheat resilience to high temperature and drought stress

Journal of Experimental Botany, erac160, http://doi.org/10.1093/jxb/erac160

Abstract 

Interannual and local fluctuations in wheat crop yield are majorly explained by abiotic constraints. Heatwaves and drought, which are among the top stressors, commonly co-occur, and their frequency is increasing with global climate change. High-throughput methods were optimised to phenotype wheat plants under controlled water deficit and high temperature, with the aim to identify phenotypic traits conferring adaptative stress responses. Wheat plants of 10 genotypes were grown in a fully automated plant facility under 25/18ºC day/night for 30 days, and then the temperature was increased for seven days (38/31ºC day/night) while maintaining half of the plants well irrigated and half at 30% field capacity. Thermal and multispectral images and pot weights were registered twice daily. At the end of the experiment, key metabolites and enzyme activities from the carbohydrate and antioxidant metabolisms were quantified. Regression machine learning models were successfully established to predict plant biomass using image-extracted parameters. Evapotranspiration traits expressed significant genotype-environment interactions (GxE) when acclimatization to stress was continuously monitored. Consequently, transpiration efficiency was essential to maintain the balance between water-saving strategies and biomass production in wheat under water deficit and high temperature. Stress tolerance included changes in the carbohydrate metabolism, particularly in the sucrolytic and glycolytic pathways, and in the antioxidant metabolism. The observed genetic differences in sensitivity to high temperature and water deficit can be exploited in breeding programs to improve wheat resilience to climate change. 

Key words：

Carbohydrate metabolism, climate change, drought resilience, food security, high temperature, high-throughput plant phenotyping, multispectral imaging, Triticum aestivum, water deficit, wheat