Comparison of the measurements of leaf water potential between a hydraulic press and a pressure chamber in six Sahelian woody species

SUMMARYIn the application of the Scholander pressure chamber technique to cassava water relations studies, the leaf water potential measured on central lobules was initially compared with that measured on entire leaves (including petiole). Measurements made using both a Campbell-Brewster hydraulic press and a pressure chamber of the leaf water potential in six different cassava clones were also compared. Although the central lobules showed a greater sensitivity to moisture loss after sampling than entire leaves, their leaf water potential was in close agreement with those measured on the entire leaves (r3 = 0·96). Therefore, for routine and field estimates in cassava, measurements made on the central lobules may be used to avoid the large reduction in total leaf area. The Campbell-Brewster hydraulic press satisfactorily estimated leaf water potential in M.Col. 1684 clone, which had the longest and narrowest lobules, but in other clones the leaf water potential was overestimated at high leaf potential (> -12·5) and underestimated at low water potentials (< -12·5). Over a wide range of leaf water potentials, a poor relationship between leaf water potentials estimated with hydraulic press and with the pressure chamber was observed for cassava because press estimates are influenced by lobule length and lobule width.

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Hydraulic Press Measurements of Leaf Water Potential in Groundnuts

Experimental Agriculture ◽

10.1017/s0014479700012758 ◽

1983 ◽

Vol 19 (4) ◽

pp. 287-291 ◽

Cited By ~ 9

Author(s):

G. Rajendrudu ◽

M. Singh ◽

J. H. Williams

Keyword(s):

Regression Analysis ◽

Water Potential ◽

Leaf Water Potential ◽

Error Variance ◽

Hydraulic Press ◽

Pressure Chamber ◽

Leaf Water ◽

Dew Point ◽

Functional Relations ◽

The Press

SUMMARYThe hydraulic press was compared with the dew point psychrometer and the pressure chamber methods for measuring leaf water potential (Ψ) in groundnuts (Arachis hypogaea L.). For measurements on the same leaf, regression analysis revealed that the slopes did not differ significantly from unity. An analysis of functional relations between measurements made by the press and the dew point psychrometer or the press and the pressure chamber showed that the error variance of the press was similar to those of the two other methods. Therefore, we conclude that for groundnuts the performance of the press, the dew point psychrometer and the pressure chamber are similar.

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Comparisons between Press and Pressure Chamber Techniques for Measuring Leaf Water Potential

Experimental Agriculture ◽

10.1017/s001447970001125x ◽

1981 ◽

Vol 17 (1) ◽

pp. 75-84 ◽

Cited By ~ 9

Author(s):

T. M. Yegappan ◽

B. J. Mainstone

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Elaeis Guineensis ◽

Water Status ◽

High Water ◽

Hydraulic Press ◽

Pressure Chamber ◽

Leaf Water ◽

Wide Range ◽

The Press

SUMMARYA hydraulic press (the J-14) was compared with a Scholander pressure chamber to measure leaf water potential in Theobroma cacao, Gliricidia maculata, Cajanus cajan and Elaeis guineensis. Although the press satisfactorily estimated water status in soft, unhardened leaves of T. cacao, G. maculata and C. cajan at high water potential, it underestimated water status in hardened leaves of T. cacao. Satisfactory estimates were obtained at low water potential for hardened leaves of T. cacao but not for the others. There was a poor relation between readings of the two instruments for E. guineensis over a wide range of water potentials because press readings appeared to be influenced by leaf structure.

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Use of a Hydraulic Press for Estimation of Leaf Water Potential in Grain Sorghum 1

Agronomy Journal ◽

10.2134/agronj1986.00021962007800040038x ◽

1986 ◽

Vol 78 (4) ◽

pp. 749-751 ◽

Cited By ~ 7

Author(s):

S. K. Hicks ◽

R. J. Lascano ◽

C. W. Wendt ◽

A. B. Onken

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Grain Sorghum ◽

Hydraulic Press ◽

Leaf Water

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Divergence in plant water-use strategies in semiarid woody species

Functional Plant Biology ◽

10.1071/fp17079 ◽

2017 ◽

Vol 44 (11) ◽

pp. 1134 ◽

Cited By ~ 8

Author(s):

Rachael H. Nolan ◽

Kendal A. Fairweather ◽

Tonantzin Tarin ◽

Nadia S. Santini ◽

James Cleverly ◽

...

Keyword(s):

Water Potential ◽

Leaf Area ◽

Leaf Water Potential ◽

Specific Leaf Area ◽

Osmotic Potential ◽

Water Status ◽

Stomatal Closure ◽

Woody Species ◽

Leaf Water ◽

Leaf Water Status

Partitioning of water resources amongst plant species within a single climate envelope is possible if the species differ in key hydraulic traits. We examined 11 bivariate trait relationships across nine woody species found in the Ti-Tree basin of central Australia. We found that species with limited access to soil moisture, evidenced by low pre-dawn leaf water potential, displayed anisohydric behaviour (e.g. large seasonal fluctuations in minimum leaf water potential), had greater sapwood density and lower osmotic potential at full turgor. Osmotic potential at full turgor was positively correlated with the leaf water potential at turgor loss, which was, in turn, positively correlated with the water potential at incipient stomatal closure. We also observed divergent behaviour in two species of Mulga, a complex of closely related Acacia species which range from tall shrubs to low trees and dominate large areas of arid and semiarid Australia. These Mulga species had much lower minimum leaf water potentials and lower specific leaf area compared with the other seven species. Finally, one species, Hakea macrocarpa A.Cunn ex.R.Br., had traits that may allow it to tolerate seasonal dryness (through possession of small specific leaf area and cavitation resistant xylem) despite exhibiting cellular water relations that were similar to groundwater-dependent species. We conclude that traits related to water transport and leaf water status differ across species that experience differences in soil water availability and that this enables a diversity of species to exist in this low rainfall environment.

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Vine water deficit : among the 3 applications of pressure chamber, stem water potential is the most sensitive indicator

OENO One ◽

10.20870/oeno-one.2000.34.4.996 ◽

2000 ◽

Vol 34 (4) ◽

pp. 169

Author(s):

Xavier Choné ◽

Olivier Trégoat ◽

Cornelis Van Leeuwen ◽

Denis Dubourdieu

Keyword(s):

Water Potential ◽

Water Deficit ◽

Leaf Water Potential ◽

Water Status ◽

Pressure Chamber ◽

Leaf Water ◽

Sensitive Indicator ◽

Stem Water Potential ◽

Water Deficits ◽

Stem Water

<p style="text-align: justify;">Vine water status is an important factor in grape quality. High tannin and anthocyanin content in red grape berries are related to moderate vine water deficits. Hence, a simple and sensitive indicator is required to determine vine water status and especially water constraint. Pressure chamber allows a quick and easy to practice determination of water status in the vineyard. Three applications of pressure chamber are known: predawn leaf water potential (ΨB), leaf water potential (ΨF) and stem water potential (ΨT). Only ΨB and ΨF are widely used on vines. In this survey ΨB, ΨF, ΨT and transpiration flow were measured on mature leaves to determine non-irrigated vine water status in field grown vines during the growing season. In California as well as in France, stem Ψ was the most discriminating indicator for both moderate and severe water deficits. In every plot surveyed ΨT was much better correlated to leaf transpiration than ΨF. Moreover, ΨT revealed nascent water deficit earlier than ΨB did. Among the three application of pressure chamber, ΨT was the only one to indicate short term water deficit after a rainfall. Hence, ΨT appears to be a useful indicator for grapevine management in both non-irrigated and irrigated vineyards.</p>

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Exclusion Errors in Pressure Chamber Estimates of Leaf Water Potential

Annals of Botany ◽

10.1093/oxfordjournals.aob.a085009 ◽

1975 ◽

Vol 39 (4) ◽

pp. 915-920 ◽

Cited By ~ 26

Author(s):

B. D. MILLAR ◽

G. K. HANSEN

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Pressure Chamber ◽

Leaf Water

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Errors Arising From Rapid Water Loss in the Measurement of Leaf Water Potential by the Pressure Chamber Technique

Functional Plant Biology ◽

10.1071/pp9800527 ◽

1980 ◽

Vol 7 (5) ◽

pp. 527 ◽

Cited By ~ 84

Author(s):

NC Turner ◽

MJ Long

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Water Loss ◽

Water Retention ◽

Pressure Chamber ◽

Leaf Water ◽

Diurnal Changes ◽

Water Potentials ◽

Retention Characteristics ◽

Flow Through

In rapidly transpiring leaves, the water potentials of uncovered leaves measured in a pressure chamber were 0.2-0.7 MPa lower than the water potentials of leaves that were covered with a plastic sheath from just prior to their excision to the completion of the measurement. The error in the water potential of uncovered leaves arose from rapid water loss in the first 30 s after excision. The degree to which the water potentials were lowered depended on the rate of transpiration, the leaf water potential at the time of excision, the species, and whether the plants were grown in the glasshouse or field. It is suggested that the variation between species and between glasshouse-grown and field-grown plants arises from differences in water retention characteristics of plant tissue as well as to differences in the rates of transpiration at excision. The size of the error induced by the rapid water loss on diurnal changes in leaf water potential is demonstrated and the effect of the error in the calculation of turgor potentials and in the resistances to water flow through the plant is discussed.

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