TY - JOUR
T1 - Leaf water potential measurements using the pressure chamber : synthetic testing of assumptions towards best practices for precision and accuracy
AU - Rodriguez-Dominguez, Celia M.
AU - Forner, Alicia
AU - Martorell, Sebastia
AU - Choat, Brendan
AU - Lopez, Rosana
AU - Peters, Jennifer M. R.
AU - Pfautsch, Sebastian
AU - Mayr, Stefan
AU - Carins-Murphy, Madeline R.
AU - McAdam, Scott A. M.
AU - Richardson, Freya
AU - Diza-Espejo, Antonio
AU - Hernandez-Santana, Virginia
AU - Menezes-Silva, Paulo E.
AU - Torres-Ruiz, Jose M.
AU - Batz, Timothy A.
AU - Sack, Lawren
PY - 2022
Y1 - 2022
N2 - Leaf water potential (ψleaf), typically measured using the pressure chamber, is the most important metric of plant water status, providing high theoretical value and information content for multiple applications in quantifying critical physiological processes including drought responses. Pressure chamber measurements of ψleaf (ψleafPC) are most typical, yet, the practical complexity of the technique and of the underlying theory has led to ambiguous understanding of the conditions to optimize measurements. Consequently, specific techniques and precautions diversified across the global research community, raising questions of reliability and repeatability. Here, we surveyed specific methods of ψleafPC from multiple laboratories, and synthesized experiments testing common assumptions and practices in ψleafPC for diverse species: (i) the need for equilibration of previously transpiring leaves; (ii) leaf storage before measurement; (iii) the equilibration of ψleaf for leaves on bagged branches of a range of dehydration; (iv) the equilibration of ψleaf across the lamina for bagged leaves, and the accuracy of measuring leaves with artificially ‘elongated petioles’; (v) the need in ψleaf measurements for bagging leaves and high humidity within the chamber; (vi) the need to avoid liquid water on leaf surfaces; (vii) the use of ‘pulse’ pressurization versus gradual pressurization; and (viii) variation among experimenters in ψleafPC determination. Based on our findings we provide a best practice protocol to maximise accuracy, and provide recommendations for ongoing species‐specific tests of important assumptions in future studies.
AB - Leaf water potential (ψleaf), typically measured using the pressure chamber, is the most important metric of plant water status, providing high theoretical value and information content for multiple applications in quantifying critical physiological processes including drought responses. Pressure chamber measurements of ψleaf (ψleafPC) are most typical, yet, the practical complexity of the technique and of the underlying theory has led to ambiguous understanding of the conditions to optimize measurements. Consequently, specific techniques and precautions diversified across the global research community, raising questions of reliability and repeatability. Here, we surveyed specific methods of ψleafPC from multiple laboratories, and synthesized experiments testing common assumptions and practices in ψleafPC for diverse species: (i) the need for equilibration of previously transpiring leaves; (ii) leaf storage before measurement; (iii) the equilibration of ψleaf for leaves on bagged branches of a range of dehydration; (iv) the equilibration of ψleaf across the lamina for bagged leaves, and the accuracy of measuring leaves with artificially ‘elongated petioles’; (v) the need in ψleaf measurements for bagging leaves and high humidity within the chamber; (vi) the need to avoid liquid water on leaf surfaces; (vii) the use of ‘pulse’ pressurization versus gradual pressurization; and (viii) variation among experimenters in ψleafPC determination. Based on our findings we provide a best practice protocol to maximise accuracy, and provide recommendations for ongoing species‐specific tests of important assumptions in future studies.
UR - https://hdl.handle.net/1959.7/uws:70775
U2 - 10.1111/pce.14330
DO - 10.1111/pce.14330
M3 - Article
SN - 1365-3040
SN - 0140-7791
VL - 45
SP - 2037
EP - 2061
JO - Plant, Cell and Environment
JF - Plant, Cell and Environment
IS - 7
ER -