Langan Patrick, Cavel Emilie, Henchy Joey, Bernád Villő, Ruel Paul, O'Dea Katie, Yatagampitiya Keshawa, Demailly Hervé, Gutierrez Laurent, Negrão Sónia
School of Biology and Environmental Science, University College Dublin, Dublin, Ireland.
Centre de Ressources Régionales en Biologie Moléculaire, Université de Picardie Jules Verne, Amiens, France.
Plant Methods. 2024 Sep 28;20(1):146. doi: 10.1186/s13007-024-01256-6.
Waterlogging is expected to become a more prominent yield restricting stress for barley as rainfall frequency is increasing in many regions due to climate change. The duration of waterlogging events in the field is highly variable throughout the season, and this variation is also observed in experimental waterlogging studies. Such variety of protocols make intricate physiological responses challenging to assess and quantify. To assess barley waterlogging tolerance in controlled conditions, we present an optimal duration and setup of simulated waterlogging stress using image-based phenotyping. Six protocols durations, 5, 10, and 14 days of stress with and without seven days of recovery, were tested. To quantify the physiological effects of waterlogging on growth and greenness, we used top down and side view RGB (Red-Green-Blue) images. These images were taken daily throughout each of the protocols using the PSI PlantScreen™ imaging platform. Two genotypes of two-row spring barley, grown in glasshouse conditions, were subjected to each of the six protocols, with stress being imposed at the three-leaf stage. Shoot biomass and root imaging data were analysed to determine the optimal stress protocol duration, as well as to quantify the growth and morphometric changes of barley in response to waterlogging stress. Our time-series results show a significant growth reduction and alteration of greenness, allowing us to determine an optimal protocol duration of 14 days of stress and seven days of recovery for controlled conditions. Moreover, to confirm the reproducibility of this protocol, we conducted the same experiment in a different facility equipped with RGB and chlorophyll fluorescence imaging sensors. Our results demonstrate that the selected protocol enables the assessment of genotypic differences, which allow us to further determine tolerance responses in a glasshouse environment. Altogether, this work presents a new and reproducible image-based protocol to assess early stage waterlogging tolerance, empowering a precise quantification of waterlogging stress relevant markers such as greenness, Fv/Fm and growth rates.
由于气候变化导致许多地区降雨频率增加，涝害预计将成为限制大麦产量的一个更为突出的胁迫因素。田间涝害事件的持续时间在整个季节中变化很大，这种变化在实验性涝害研究中也有观察到。如此多样的实验方案使得复杂的生理反应难以评估和量化。为了在可控条件下评估大麦的耐涝性，我们使用基于图像的表型分析方法，给出了模拟涝害胁迫的最佳持续时间和设置。测试了六种方案持续时间，即胁迫5天、10天和14天，以及有和没有7天恢复期的情况。为了量化涝害对生长和绿色度的生理影响，我们使用了自上而下和侧视图的RGB（红-绿-蓝）图像。在每个方案的整个过程中，每天使用PSI PlantScreen™成像平台拍摄这些图像。在温室条件下种植的两种基因型的二棱春大麦，每种都接受六种方案中的一种，胁迫在三叶期施加。分析地上部生物量和根系成像数据，以确定最佳胁迫方案持续时间，以及量化大麦在响应涝害胁迫时的生长和形态变化。我们的时间序列结果显示生长显著减少和绿色度改变，这使我们能够确定在可控条件下14天胁迫和7天恢复的最佳方案持续时间。此外，为了确认该方案的可重复性，我们在配备RGB和叶绿素荧光成像传感器的不同设施中进行了相同的实验。我们的结果表明，所选方案能够评估基因型差异，这使我们能够在温室环境中进一步确定耐受性反应。总之，这项工作提出了一种新的、可重复的基于图像的方案来评估早期耐涝性，能够精确量化与涝害胁迫相关的标记，如绿色度、Fv/Fm和生长速率。
