Chamber‐based system for measuring whole‐plant transpiration dynamics. Issue 6 (2nd November 2022)

• Record Type: Journal Article
• Authors: Pieters, Alejandro; Giese, Marcus; Schmierer, Marc; Johnson, Kristian; Asch, Folkard
• Is Part Of: Plant-environment interactions. Volume 3:Issue 6(2022)
• Page Start: 243
• Page End: 253
• Publication Date: 2022-11-02
• Subjects: environmental drivers -- gravimetry -- transpiration -- VPD -- whole plant; Plant ecology -- Periodicals; Plants -- Periodicals; 581.7
• DOI: 10.1002/pei3.10094
• Languages: English
• ISSNs: 2575-6265

Abstract

Abstract: Most of our insights on whole‐plant transpiration (E) are based on leaf‐chamber measurements using water vapor porometers, IRGAs, or flux measurements. Gravimetric methods are integrative, accurate, and a clear differentiation between evaporation and E can be made. Water vapor pressure deficit (VPD) is the driving force for E but assessing its impact has been evasive, due to confounding effects of other climate drivers. We developed a chamber‐based gravimetric method, in which whole plant response of E to VPD could be assessed, while keeping other environmental parameters at predetermined values. Stable VPD values (0.5–3.7 kPa) were attained within 5 min after changing flow settings and maintained for at least 45 min. Species differing in life form and photosynthetic metabolism were used. Typical runs covering the range of VPDs lasted up to 4 h, preventing acclimation responses or soilborne water deficit. Species‐specific responses of E to VPD could be identified, as well as differences in leaf conductance. The combined gravimetric‐chamber‐based system presented overcomes several limitations of previous gravimetric set ups in terms of replicability, time, and elucidation of the impact of specific environmental drivers on E, filling a methodological gap and widening our phenotyping capabilities. Abstract : Most insights on transpiration (E) are based on leaf‐chamber measurements using water vapor porometers, IRGAs, or flux measurements. We developed a chamber‐based gravimetric method, to unequivocally assess plant response of E to VPD. The result is an affordable and reliable system that can be used to study the interaction between atmosphere and E at the whole‐plant level.