Differences between tree species in hydraulic press calibration of leaf water potential are correlated with specific leaf area.

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.

Download Full-text

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

Download Full-text

El Niño-Southern Oscillation affects the water relations of tree species in the Yucatan Peninsula, Mexico

Scientific Reports ◽

10.1038/s41598-021-89835-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jorge Palomo-Kumul ◽

Mirna Valdez-Hernández ◽

Gerald A. Islebe ◽

Manuel J. Cach-Pérez ◽

José Luis Andrade

Keyword(s):

Water Potential ◽

Leaf Area ◽

Tropical Forests ◽

Specific Leaf Area ◽

Tree Species ◽

Deciduous Species ◽

Mature Trees ◽

Seasonally Dry ◽

Seasonally Dry Tropical Forests ◽

Dry Tropical Forests

AbstractWe evaluated the effect of ENSO 2015/16 on the water relations of eight tree species in seasonally dry tropical forests of the Yucatan Peninsula, Mexico. The functional traits: wood density, relative water content in wood, xylem water potential and specific leaf area were recorded during the rainy season and compared in three consecutive years: 2015 (pre-ENSO conditions), 2016 (ENSO conditions) and 2017 (post-ENSO conditions). We analyzed tree size on the capacity to respond to water deficit, considering young and mature trees, and if this response is distinctive in species with different leaf patterns in seasonally dry tropical forests distributed along a precipitation gradient (700–1200 mm year−1). These traits showed a strong decrease in all species in response to water stress in 2016, mainly in the driest site. Deciduous species had lower wood density, higher predawn water potential and higher specific leaf area than evergreen species. In all cases, mature trees were more tolerant to drought. In the driest site, there was a significant reduction in water status, regardless of their leaf phenology, indicating that seasonally dry tropical forests are highly vulnerable to ENSO. Vulnerability of deciduous species is intensified in the driest areas and in the youngest trees.

Download Full-text

Evaluation of the hydraulic press for measurement of leaf water potentials in cassava

The Journal of Agricultural Science ◽

10.1017/s0021859600037734 ◽

1983 ◽

Vol 101 (2) ◽

pp. 407-410 ◽

Cited By ~ 1

Author(s):

J. A. Palta

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Hydraulic Press ◽

Pressure Chamber ◽

Leaf Water ◽

Moisture Loss ◽

Total Leaf Area ◽

Water Potentials ◽

Wide Range ◽

Poor Relationship

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.

Download Full-text

Predictors and mechanisms of the drought-influenced mortality of tree species along the isohydric to anisohydic continuum in a decade-long study of a central US temperate forest

Biogeosciences Discussions ◽

10.5194/bgd-12-1285-2015 ◽

2015 ◽

Vol 12 (2) ◽

pp. 1285-1325 ◽

Cited By ~ 5

Author(s):

L. Gu ◽

S. G. Pallardy ◽

K. P. Hosman ◽

Y. Sun

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Tree Species ◽

Tree Mortality ◽

Leaf Water ◽

Extreme Drought ◽

Positive Temperature ◽

Drought Intensity ◽

Predawn Leaf Water Potential ◽

Annual Variations

Abstract. Using decade-long continuous observations of tree mortality and predawn leaf water potential (ψpd) at the Missouri Ozark AmeriFlux (MOFLUX) site, we studied how the mortality of important tree species varied along the isohydric to anisohydric continuum and how such variations may be predicted. Water stress determined inter-annual variations in tree mortality with a time delay of one year or more, which was predicted by predawn leaf water potential integral (PLWPI), mean effective precipitation interval (a time period with no daily precipitation rates exceeding a threshold) with a daily threshold precipitation at 5 mm day−1 (MEPI5), and precipitation variability index (PVI). Positive temperature anomaly integral (PTAI) and vapor pressure deficit integral (VPDI) also worked reasonably well, particularly for moderate droughts. The extreme drought of the year 2012 drastically increased the mortality of all species in the subsequent year. Regardless of the degree of isohydry and drought intensity, the ψpd of all species recovered rapidly after sufficiently intense rain events. This, together with a lack of immediate leaf and branch desiccation, suggests that hydraulic disconnection in the xylem was absent even during extreme drought and tree death was caused by significant but indirect effects of drought. We also found that species occupying middle positions along the isohydric to anisohydric continuum suffered less mortality than those at either extremes (i.e. extremely isohydric or extremely anisohydric). Finally, our study suggested that species differences in mortality mechanisms can be overwhelmed and masked in extreme droughts and should be examined in a broad range of drought intensity.

Download Full-text

The dynamics of rooting in Triplochiton scleroxylon cuttings: their relation to leaf area, node position, dry weight accumulation, leaf water potential and carbohydrate composition

Tree Physiology ◽

10.1093/treephys/5.1.135 ◽

1989 ◽

Vol 5 (1) ◽

pp. 135-146 ◽

Cited By ~ 39

Author(s):

R. R. B. Leakey ◽

M. P. Coutts

Keyword(s):

Water Potential ◽

Leaf Area ◽

Leaf Water Potential ◽

Dry Weight ◽

Leaf Water ◽

Carbohydrate Composition ◽

Node Position

Download Full-text

Relationship between specific leaf area, leaf thickness, leaf water content and SPAD-502 readings in six Amazonian tree species

Photosynthetica ◽

10.1007/s11099-009-0031-6 ◽

2009 ◽

Vol 47 (2) ◽

pp. 184-190 ◽

Cited By ~ 88

Author(s):

R.A. Marenco ◽

S.A. Antezana-Vera ◽

H.C.S. Nascimento

Keyword(s):

Water Content ◽

Leaf Area ◽

Specific Leaf Area ◽

Tree Species ◽

Leaf Water ◽

Leaf Thickness ◽

Leaf Water Content

Download Full-text

Rootstock Genotypes Shape the Response of cv. Pinot gris to Water Deficit

Agronomy ◽

10.3390/agronomy11010075 ◽

2020 ◽

Vol 11 (1) ◽

pp. 75

Author(s):

Michele Faralli ◽

Pier Lugi Bianchedi ◽

Massimo Bertamini ◽

Claudio Varotto

Keyword(s):

Water Stress ◽

Water Potential ◽

Leaf Area ◽

Water Use ◽

Leaf Water Potential ◽

Water Availability ◽

Leaf Water ◽

Daily Water ◽

Shallow Soils ◽

Reduced Water

Understanding the physiological basis underlying the water stress responses in grapevine is becoming increasingly topical owing to the challenges that climate change will impose to grapevine agriculture. Here we used cv. Pinot gris (clone H1), grafted on a series of tolerant (1103Paulsen; P), sensitive (SO4) and recently selected (Georgikon28; G28, Georgikon121; G121, Zamor17; Z17) rootstocks. Plants were either subjected to reduced water availability (WS) or maintained at pot capacity (WW). Photosynthetic (light response curves), stomatal and in vivo gas exchange analysis were carried out as well as dynamics of daily water use (WU), leaf area accumulation with affordable RGB imaging pipelines and leaf water potential. Significant genotypic variation was recorded between rootstocks for most of the traits analyzed under optimal conditions with P and SO4 showing a more vigorous growth, higher CO2 assimilation rate, stomatal conductance and stomatal density per unit of leaf area than G28, G121, Z17 (p < 0.001). Under WS, rootstocks induced different water stress response in Pinot gris, with G28 and G121 showing a higher sensitivity of water use to reduced water availability (WS) (p = 0.021) and no variation for midday leaf water potential until severe WS. P, Z17 and to some extent SO4 induced a pronounced near-anisohydric response with a general WU maintenance followed by reduction in leaf water potential even at high levels of soil water content. In addition, G28 and G121 showed a less marked slope in the linear relationship between daily water use and VPD (p = 0.008) suggesting elevated sensitivity of transpiration to evaporative demand. This led to an insensitivity for total dry weight biomass of G28 and G121 under WS conditions (p < 0.001). This work provides: (i) an in-depth analysis for a series of preferable traits under WS in Pinot gris; (ii) a characterization of Pinot gris × rootstock interaction and a series of desirable traits under WS induced by several rootstocks; (iii) the potential benefit for the use a series of affordable methods (e.g., RGB imaging) to easily detect dynamic changes in biomass in grapevine and quickly phenotype genotypes with superior responses under WS. In conclusion, the near-isohydric and conservative behavior observed for G28 and G121 coupled with their low vigor suggest them as potential Pinot gris rootstock candidates for sustaining grapevine productivity in shallow soils likely to develop terminal stress conditions.

Download Full-text

Terrestrial Laser Scanning Intensity Captures Diurnal Variation in Leaf Water Potential

10.20944/preprints202005.0426.v1 ◽

2020 ◽

Author(s):

Samuli Junttila ◽

Teemu Hölttä ◽

Eetu Puttonen ◽

Masato Katoh ◽

Mikko Vastaranta ◽

...

Keyword(s):

Diurnal Variation ◽

Water Potential ◽

Leaf Water Potential ◽

Tree Species ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Leaf Water ◽

Water Dynamics ◽

Plant Water ◽

Plant Mortality

Drought-induced plant mortality has increased globally during the last decades and is forecasted to influence global vegetation dynamics. Timely information on plant water dynamics is essential for understanding and anticipating drought-induced plant mortality. The most common metric that has been used for decades for measuring water stress is leaf water potential (ΨL), which is measured destructively. To obtain information on water dynamics from trees and forested landscapes, remote sensing methods have been developed. However, the spatial and temporal resolution of the existing methods have limited our understanding of water dynamics and diurnal variation of ΨL within single trees. Thus, we investigated the capability of terrestrial laser scanning (TLS) intensity in observing diurnal variation in ΨL during a 50 hour monitoring period and aimed to improve understanding on how large part of the diurnal variation in ΨL can be captured using intensity observations. We found that TLS intensity at 905 nm wavelength was able to explain 78% of the variation in ΨL for three trees of two tree species with a root-mean square error of 0.137 MPa. Based on our experiment with three trees, time-series of TLS intensity measurements can be used in detecting changes in ΨL, and thus it is worthwhile to expand the investigations to cover a wider range of tree species and forests and further increase our understanding of plant water dynamics at wider spatial and temporal scales.

Download Full-text