de Ollas Carlos, Segarra-Medina Clara, González-Guzmán Miguel, Puertolas Jaime, Gómez-Cadenas Aurelio
1Departamento de Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Castellón de la Plana, Spain.
2Lancaster Environment Centre, Lancaster University, Lancaster, UK.
Plant Methods. 2019 Aug 2;15:89. doi: 10.1186/s13007-019-0474-0. eCollection 2019.
Characterization of the dynamic response of plant transpiration to decreasing soil water content in a reproducible way is required for the correct phenotyping of traits related to water saving strategies. Nowadays, an increasing number of automated high throughput platforms are available, but their development requires a great economic investment and it is not always desirable/feasible to outsource these analyses. We propose a medium-throughput protocol to characterize transpiration responses to decreasing soil moisture in a quantitative and highly reproducible way with a minimum investment of resources.
The quantitative characterization of plant responses to a decreasing soil water content using our phenotyping platform has showed high reproducibility between different experiments. The proposed irrigation strategy allowed us to harvest plants ranging from a well-watered condition to the loss-of-turgor point in a predictable and controlled way. Coupling this protocol with hormone profiling allows investigation of hormonal responses (metabolite accumulation as well as plant sensitivity) to water stress. As a proof-of-concept, we have characterized the dynamic responses of leaf transpiration to decreasing soil water contents in an abscisic acid (ABA) deficient genotype (-) as well as in genotypes with altered sensitivity to ABA (- and --), which are insensitive and hypersensitive to ABA, respectively.
This protocol allows for assessment of quantitative differences in rosette transpiration responses to water depletion in both ABA biosynthesis mutants and genotypes with altered sensitivity to the hormone. Data indicate a correlation between ABA levels and/or hormone perception and growth rate and/or water content. The protocol guarantees the correct application of water stress to adult plants, which is essential to understand responses of mutants and/or natural accessions.
以可重复的方式表征植物蒸腾作用对土壤含水量降低的动态响应，对于与节水策略相关性状的正确表型分析是必要的。如今，越来越多的自动化高通量平台可供使用，但它们的开发需要大量经济投入，而且将这些分析外包并不总是可取/可行的。我们提出了一种中通量方案，以最少的资源投入，定量且高度可重复地表征蒸腾作用对土壤湿度降低的响应。
使用我们的表型分析平台对植物对土壤含水量降低的响应进行定量表征，结果表明不同实验之间具有高度可重复性。所提出的灌溉策略使我们能够以可预测和可控的方式收获处于从充分浇水状态到膨压丧失点之间不同状态的植物。将该方案与激素谱分析相结合，可以研究激素对水分胁迫的响应（代谢物积累以及植物敏感性）。作为概念验证，我们表征了脱落酸（ABA）缺陷型基因型（-）以及对ABA敏感性改变的基因型（-和--）（分别对ABA不敏感和超敏感）叶片蒸腾作用对土壤含水量降低的动态响应。
该方案能够评估ABA生物合成突变体以及对该激素敏感性改变的基因型中莲座叶蒸腾作用对水分亏缺响应的定量差异。数据表明ABA水平和/或激素感知与生长速率和/或含水量之间存在相关性。该方案确保了对成年植物正确施加水分胁迫，这对于理解突变体和/或自然材料的响应至关重要。
