A simple system for phenotyping of plant transpiration and stomatal conductance response to drought

Abstract

Abstract Plant breeding for increased crop water use efficiency or drought stress resistance requires methods to quickly assess the transpiration rate (E) and stomatal conductance (gs) of a large number of individual plants. Several methods to measure E and gs exist, each of which has its own drawbacks and shortcomings. To add to this toolbox, we developed a method that uses whole-plant thermal imaging in a controlled environment, where aerial humidity is changed rapidly to induce changes in E that are reflected in changes in leaf temperature. This approach is based on a simplified energy balance equation, without the need for a reference material or complicated calculations. To test this concept, we built a double-sided, perforated, open-top plexiglass chamber that was supplied with air at a high flow rate (35 L min− 1) and whose relative humidity (RH) could be switched rapidly. Measurements included air and leaf temperature as well as RH. Using several well-watered and drought stressed genotypes of Arabidopsis thaliana that were exposed to multiple cycles in RH (30 to 50% and back), we showed that leaf temperature as measured in our system correlated well with E and gs measured in a commercial gas exchange system. Our results demonstrate that, at least within a given species, the differences in leaf temperature under several RH can be used as a proxy for E and gs. Given that this method is fairly quick, noninvasive and remote, we envision that it could be upscaled for work within rapid plant phenotyping systems.

Plant phenotyping relevance

植物の蒸散・気孔コンダクタンスを熱画像から推定する新規手法を開発し、ガス交換測定との相関で検証しており、フェノタイピング手法が研究の中心である。

Code and data availability

The preprint describes a thermal-imaging phenotyping method but declares 'Availability of data and materials: Not applicable' and provides no public dataset, image, code, or model deposit. The only URL mentioned (NASC, arabidopsis.info) is a seed stock centre for obtaining Arabidopsis accessions, not a paper-specific,

No evidence-backed public reproduction asset is currently recorded.