背景回顾：Environmental stresses are among the major factors that limit crop productivity and plant growth. Various nondestructive approaches for monitoring plant stress states have been developed. 

提出问题：However, early sensing of the initial biochemical events during stress responses remains a significant challenge.

主要研究：In this work, we established whole-plant redox imaging using potato (Solanum tuberosum) plants expressing a chloroplast-targeted redox-sensitive green fluorescence protein 2 (roGFP2), which reports the glutathione redox potential (EGSH). 

结果1-ROS内稳态干扰测试：Ratiometric imaging analysis demonstrated the probe response to redox perturbations induced by H2O2, DTT, or a GSH biosynthesis inhibitor. 

结果2-胁迫测试：We mapped alteration in the chloroplast EGSH under several stress conditions including, high-light, cold and drought. An extremely high increase in chloroplast EGSH was observed under the combination of high-light and low temperatures, conditions that specifically induce PSI photoinhibition. 

结果3-植株的分级胁迫响应策略：Intriguingly, we noted a higher reduced state in newly developed compared to mature leaves under steady-state and stress conditions, suggesting a graded stress sensitivity as part of the plant strategies for coping with stress. 

结论：The presented observations suggest that whole-plant redox imaging can serve as a powerful tool for the basic understanding of plant stress responses and applied agricultural research, such as toward improving phenotyping capabilities in breeding programs and early detection of stress responses in the field.

 摘 要 

环境胁迫是限制作物生产和植物生长最主要的因素。目前，已经开发出了各种非破坏性的植物胁迫状态检测方法。但是，在胁迫响应早期，植物感知生化事件仍然不清楚。本文中，作者通过在番茄中表达靶向叶绿体的氧化还原敏感绿色荧光蛋白roGFP2，用以报告谷胱甘肽氧化还原潜力EGSH，从而建立了一个整株氧化还原可视化的体系。比率成像分析显示探针对过氧化氢、DTT或GSH生物合成抑制剂引起的氧化还原波动起响应。作者绘制了在强光、低温和干旱等胁迫条件下叶绿体EGSH的变化。在强光和低温的联合作用下，会特异性诱导PSI光抑制，结果导致叶绿体的EGSH显著增加。有趣的是，作者发现在稳定状态和胁迫条件下，与成熟叶片相比，新发育叶片具有更高的还原状态，表明分级胁迫敏感性是植物应对胁迫的一种策略。这些研究结果表明，整株植物氧化还原成像可以作为一个强大的工具，用以了解植物胁迫响应和应用农业研究，比如提高育种项目的表型观测能力和田间胁迫响应的早期检测。