PHYSIOLOGICAL AND PHENOLOGICAL VEGETATIVE RESPONSES OF Campomanesia adamantium (Cambess) O. Berg (Myrtaceae) TO THE HYDRIC SEASONALITY OF RUPESTRIAN FIELDS

ABSTRACT The rupestrian fields have two well-defined seasons throughout the year, with rainfall rates that reflect the rainy and dry seasons. This distinction in water availability affects the morphology, physiology and chemistry of plants, among other characteristics. Thus, it is aimed at evaluating the leaf water status, vegetative phenology and photosynthetic behavior of Campomanesia adamantium from a rupestrian field during the dry and rainy season. The study was conducted in Serra do Cipó, Minas Gerais, Brazil. From November 2011 to November 2012 it was examined vegetative phenophases and development of six individuals. Water potential, stomatal conductance, quantum yield and concentration of pigments were evaluated from four leaves of 3rd node per individual (n = 4-5) in the dry and rainy seasons. C. adamantium is an evergreen type and presents mature leaves and sprouting throughout the year. This species showed strategies that reduce water loss during the dry season in rupestrian field, such as decrease in stomatal conductance throughout the day, also associated with a reduction in leaf water potential. However, low water availability did not affect the photosynthetic performance, which enables the construction of new leaves and renovation of the crown even in dry periods. Finally, little reduction in the values of Fv/Fm throughout the day and increase the values of ΔF/Fm' in warmer times, both in the dry season, reiterates the ability of C. adamantium to adjust their physiology to seasonal water deficit of the rupestrian field.

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Effect of Water Stress on Stomatal Conductance and Leaf Water Relations of Leaves Along Current-Year Branches of Peach

Functional Plant Biology ◽

10.1071/pp9890549 ◽

1989 ◽

Vol 16 (6) ◽

pp. 549 ◽

Cited By ~ 4

Author(s):

SL Steinberg ◽

MJ Mcfarland ◽

JC Miller

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Water Potential ◽

Water Status ◽

Stomatal Closure ◽

Water Flux ◽

Leaf Water ◽

Leaf Water Status ◽

Mature Leaves ◽

Water Potentials

A gradation, that reflects the maturity of the leaves, exists in the leaf water, osmotic and turgor potential and stomatal conductance of leaves along current and 1-year-old branches of peach. Predawn leaf water potentials of immature folded leaves were approximately 0.24 MPa lower than mature leaves under both well-watered and dry conditions. During the daytime the leaf water potential of immature leaves reflected the water potential produced by water flux for transpiration. In well- watered trees, mature and immature unfolded leaves had a solute potential at least 0.5 MPa lower than immature folded leaves, resulting in a turgor potential that was approximately 0.8 MPa higher. The turgor requirement for growth appeared to be much less than that maintained in mature leaves. As water stress developed and leaf water potentials decreased, the osmotic potential of immature folded leaves declined to the level found in mature leaves, thus maintaining turgor. In contrast, mature leaves showed little evidence of turgor maintenance. Stomatal conductance was lower in immature leaves than in fully mature leaves. With the onset of water stress, conductance of mature leaves declined to a level near that of immature leaves. Loss of turgor in mature leaves may be a major factor in early stomatal closure. It was concluded that osmotic adjustment played a role in maintenance of a leaf water status favorable for some growth in water-stressed immature peach leaves.

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Seasonal leaf gas exchange and water potential in a woody cerrado species community

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202004000100002 ◽

2004 ◽

Vol 16 (1) ◽

pp. 7-16 ◽

Cited By ~ 42

Author(s):

Carlos Henrique Britto de Assis Prado ◽

Zhang Wenhui ◽

Manuel Humberto Cardoza Rojas ◽

Gustavo Maia Souza

Keyword(s):

Gas Exchange ◽

Water Potential ◽

Leaf Water Potential ◽

Leaf Gas Exchange ◽

Water Status ◽

Dry Season ◽

Leaf Water ◽

Wet Season ◽

Leaf Water Status ◽

Mean Values

Predawn leaf water potential (psipd) and morning values of leaf gas exchange, as net photosynthesis (A), stomatal conductance (gs), transpiration (E), and morning leaf water potential (psimn) were determined seasonally in 22 woody cerrado species growing under natural conditions. Despite the lower mean values of psipd in the dry season (-0.35 ± 0.23 MPa) compared to the wet season (-0.08 ± 0.03 MPa), the lowest psipd in the dry season (-0.90 ± 0.00 MPa) still showed a good nocturnal leaf water status recovery for all species studied through out the year. Mean gs values dropped 78 % in the dry season, when the vapor pressure of the air was 80% greater than in the wet season. This reduction in gs led to an average reduction of 33% in both A and E, enabling the maintainance of water use efficiency (WUE) during the dry season. Network connectance analysis detected a change in the relationship between leaf gas exchange and psimn in the dry season, mainly between gs-E and E-WUE. A slight global connectance value increase (7.25 %) suggested there was no severe water stress during the dry season. Multivariate analysis showed no link between seasonal response and species deciduousness, suggesting similar behavior in remaining leaves for most of the studied species concerning leaf gas exchange and psimn under natural drought.

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Stomatal Responses and Whole-Tree Hydraulic Conductivity of Orchard Macadamia integrifolia Under Irrigated and Non-Irrigated Conditions

Functional Plant Biology ◽

10.1071/pp9910661 ◽

1991 ◽

Vol 18 (6) ◽

pp. 661 ◽

Cited By ~ 9

Author(s):

J Lloyd ◽

T Trochoulias ◽

R Ensbey

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Leaf Water Potential ◽

Water Status ◽

Simple Expression ◽

Leaf Water ◽

Leaf Water Status ◽

Diurnal Patterns ◽

Macadamia Integrifolia ◽

Independent Variable

Diurnal patterns of stomatal conductance (gs) and leaf water potential (Ψ1) were determined for leaves on irrigated and non-irrigated 5-year-old Macadamia integrifolia trees over a 4-month period from September to December 1989. An empirical model for stomatal conductance was developed for irrigated trees using relationships to photon irradiance (I), leaf temperature (T1) and vapour mole fraction difference (D). This model accounted for 69% of the variance in gs, and was not improved by the inclusion of Ψ1 as an independent variable. Fitted parameters led to the effective prediction of gs for untried combinations of environmental variables. By using a simple expression to link leaf water potential to transpiration rate (E), the model was extended to prediction of Ψ1 from measurements of I, T1 and D. Stornatal conductances were significantly lower on non-irrigated trees after a 2-month dry period. Lower stornatal conductances were not accompanied by more negative Ψ1 indicating that soil rather than leaf water status may control gs in macadamia trees under non-irrigated conditions.

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Geospatial variation of grapevine water status, soil water availability, grape composition and sensory characteristics in a spatially heterogeneous premium wine grape vineyard

SOIL Discussions ◽

10.5194/soild-1-1013-2014 ◽

2014 ◽

Vol 1 (1) ◽

pp. 1013-1072

Author(s):

D. R. Smart ◽

S. Cosby Hess ◽

R. Plant ◽

O. Feihn ◽

H. Heymann ◽

...

Keyword(s):

Water Potential ◽

Soil Water ◽

Leaf Water Potential ◽

Water Availability ◽

Water Status ◽

Leaf Water ◽

Sensory Characteristics ◽

Soil Water Availability ◽

Wine Grape ◽

Available Water

Abstract. The geoscience component of terroir in wine grape production continues to be criticized for its quasi-mystical nature, and lack of testable hypotheses. Nonetheless, recent relational investigations are emerging and most involve water availability as captured by available water capacity (AWC, texture) or plant available water (PAW) in the root zone of soil as being a key factor. The second finding emerging may be that the degree of microscale variability in PAW and other soil factors at the vineyard scale renders larger regional characterizations questionable. Cimatic variables like temperature are well mixed, and its influence on wine characteristic is fairly well established. The influence of mesogeology on mesoclimate factors has also been characterized to some extent. To test the hypothesis that vine water status mirrors soil water availability, and controls fruit sensory and chemical properties at the vineyard scale we examined such variables in a iconic, selectively harvested premium winegrape vineyard in the Napa Valley of California during 2007 and 2008 growing seasons. Geo-referenced data vines remained as individual study units throughout data gathering and analysis. Cartographic exercises using geographic information systems (GIS) were used to vizualize geospatial variation in soil and vine properties. Highly significant correlations (P < 0.01) emerged for pre-dawn leaf water potential (ΨPD), mid-day leaf water potential (ΨL) and PAW, with berry size, berry weight, pruning weights (canopy size) and soluble solids content (°Brix). Areas yielding grapes with perceived higher quality had vines with (1) lower leaf water potential (LWP) both pre-dawn and mid-day, (2) smaller berry diameter and weight, (3) lower pruning weights, and (4) higher °Brix. A trained sensory panel found grapes from the more water-stressed vines had significantly sweeter and softer pulp, absence of vegetal character, and browner and crunchier seeds. Metabolomic analysis of the grape skins showed significant differences in accumulation of amino acids and organic acids. Data vines were categorized as non-stressed (ΨPD ≥ −7.9 bars and ΨL ≥ −14.9 bars) and stressed (ΨPD ≤ −8.0 bars and ΨL ≤ −15.0 bars) and subjected to analysis of variance. Significant separation emerged for vines categorized as non-stressed versus stressed at véraison, which correlated to the areas described as producing higher and lower quality fruit. This report does not advocate the use of stress levels herein reported. The vineyard was planted to a vigorous, deep rooted rootstock (V. rupestris cv. St. George), and from years of management is known to be able to withstand stress levels of the magnitude we observed. Nonetheless, the results may suggest there is not a linear relationship between physiological water stress and grape sensory characteristics, but rather the presence of an inflection point controlling grape composition as well as physiological development.

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Relationship Between Root/Soil Hydraulic Properties and Stomatal Behaviour in Sugarcane

Functional Plant Biology ◽

10.1071/pp9890241 ◽

1989 ◽

Vol 16 (3) ◽

pp. 241 ◽

Cited By ~ 21

Author(s):

NZ Saliendra ◽

FC Meinzer

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Soil Water ◽

Leaf Water Potential ◽

Water Status ◽

Hydraulic Conductance ◽

Leaf Water ◽

Soil Drying ◽

Root Hydraulic Conductance ◽

High Soil Moisture

Stomatal conductance, leaf and soil water status, transpiration, and apparent root hydraulic conductance were measured during soil drying cycles for three sugarcane cultivars growing in containers in a greenhouse. At high soil moisture, transpiration and apparent root hydraulic conductance differed considerably among cultivars and were positively correlated, whereas leaf water potential was similar among cultivars. In drying soil, stomatal and apparent root hydraulic conductance approached zero over a narrow (0.1 MPa) range of soil water suction. Leaf water potential remained nearly constant during soil drying because the vapor phase conductance of the leaves and the apparent liquid phase conductance of the root system declined in parallel. The decline in apparent root hydraulic conductance with soil drying was manifested as a large increase in the hydrostatic pressure gradient between the soil and the root xylem. These results suggested that control of stomatal conductance in sugarcane plants exposed to drying soil was exerted primarily at the root rather than at the leaf level.

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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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Effects of Low Relative Humidity and Illumination on Leaf Water Status of Cucumber Seedlings and Growth of Harvested Cuttings

HortScience ◽

10.21273/hortsci.41.2.410 ◽

2006 ◽

Vol 41 (2) ◽

pp. 410-413 ◽

Cited By ~ 4

Author(s):

Toshio Shibuya ◽

Ryoko Terakura ◽

Yoshiaki Kitaya ◽

Makoto Kiyota

Keyword(s):

Relative Humidity ◽

Water Potential ◽

Leaf Water Potential ◽

Water Status ◽

Leaf Conductance ◽

Leaf Water ◽

Fresh Weight ◽

Leaf Water Status ◽

Air Temperatures ◽

Total Fresh Weight

Application of a low-relative-humidity treatment (LHT) to seedlings can reduce water stress on cuttings harvested from the seedlings, after the cuttings are planted. Effects of illumination during LHT and LHT duration on leaf water potential and leaf conductance in cucumber (Cucumis sativus L.) seedlings used as the model plant material and on growth of harvested cuttings were investigated to determine optimal LHT conditions. The seedlings received LHT for 12 or 24 h in a lighted or dark growth chamber at air temperatures of 28 to 31 °C and relative humidity of 12% to 25%. Cuttings including a foliage leaf and two cotyledons were harvested by cutting the hypocotyl of the seedlings immediately after the treatment, and then the cuttings were planted in vermiculite medium. Four days after planting, the total fresh weight of the cuttings from seedlings that had received LHT in the lighted chamber was 2.2 times that of cuttings from seedlings that had not received LHT, whereas the total fresh weight of those that had received LHT in the dark increased by 1.3 to 1.8 times. Significant effects of illumination during LHT were also observed in the transpiration rate and growth of the cuttings, harvested following the treatment, after they were planted. By varying LHT duration, it was also found that leaf water potential and leaf conductance of the seedlings decreased as LHT duration increased up to 18 h. Thus, illumination during LHT increased the growth of cuttings taken following the treatment, and optimal treatment duration of around 18 h was estimated from the seedlings' leaf conductance and leaf water potential.

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Paraheliotropic Leaf Movement of Bush Bean in Response to Water Availability and Air Temperature

HortScience ◽

10.21273/hortsci.30.4.798d ◽

1995 ◽

Vol 30 (4) ◽

pp. 798D-798

Author(s):

M. Raeini-Sarjaz ◽

N.N. Barthakur

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Air Temperature ◽

Leaf Water Potential ◽

Water Availability ◽

Leaf Water ◽

Leaf Angle ◽

Bush Bean ◽

Leaf Movements ◽

Positive Correlations

Paraheliotropic leaf movements of bush bean were studied in relation to water availability, ambient temperature, leaf water potential, and stomatal conductance in a growth chamber. Unifoliate leaf angle from the horizontal (LA), stomatal conductance (G), and leaf water potential (WP) were measured at noon to minimize the effect of leaf movements due to circadian rhythm. Photoperiod and light intensity on the foliage were kept constant at 14 h, and 200 μmol·m–2·s–1, respectively, throughout the measurements. Negative correlations were obtained between water availability (WA) and LA (R = –0.93), and WP and LA (R = –0.85), whereas positive correlations were shown between WA and WP (R = 0.90), WA and G (R = 0.90), and WP and G (0.84) at 35C air temperature. Similar correlations were observed at 25C between WA and LA (R = –0.91), WP and LA (R = –0.79), WA and WP (R = 0.91), WA and G (R = 0.68), and WP and G (R = 0.76). Air temperature significantly (P ≤ 0.01) affected leaf movements.

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Midday stomatal conductance is more related to stem rather than leaf water status in subtropical deciduous and evergreen broadleaf trees

Plant Cell & Environment ◽

10.1111/j.1365-3040.2012.02563.x ◽

2012 ◽

Vol 36 (1) ◽

pp. 149-158 ◽

Cited By ~ 72

Author(s):

YONG-JIANG ZHANG ◽

FREDERICK C. MEINZER ◽

JIN-HUA QI ◽

GUILLERMO GOLDSTEIN ◽

KUN-FANG CAO

Keyword(s):

Stomatal Conductance ◽

Water Status ◽

Leaf Water ◽

Leaf Water Status

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Photosynthesis and Leaf Water, Carbohydrate, and Hormone Status during Rooting of Stem Cuttings of Acer rubrum

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.6.1052 ◽

1991 ◽

Vol 116 (6) ◽

pp. 1052-1057 ◽

Cited By ~ 13

Author(s):

T.J. Smalley ◽

M.A. Dirr ◽

A.M. Armitage ◽

B.W. Wood ◽

R.O. Teskey ◽

...

Keyword(s):

Stomatal Conductance ◽

Water Status ◽

Soluble Sugars ◽

Acer Rubrum ◽

Net Photosynthesis ◽

Zeatin Riboside ◽

Leaf Water ◽

Stem Cuttings ◽

Leaf Water Status ◽

Photosynthetic Rates

Leaf water status, carbohydrate levels, net photosynthesis, stomatal conductance, ABA, dihydrozeatin riboside (DHZR), and trans-zeatin riboside (ZR) levels were determined in a greenhouse during rooting of stem cuttings of Acer rubrum L. `Red Sunset' taken on 3 Sept. 1987 and 28 May 1988. Leaf water status deteriorated before rooting and improved after root emergence. Leaf carbohydrate concentrations (glucose, sucrose, total soluble sugars, and total carbohydrates) increased until rooting and decreased after rooting, while changes in starch concentrations were trendless. ABA levels increased after insertion of cuttings into the rooting medium, but decreased before rooting. No correlation between timing of rooting and concentrations of the cytokinins ZR or DHZR was observed. Photosynthetic rates during rooting were higher for the Sept. 1987 cuttings and did not decrease to the compensation point as did those for May 1988 cuttings. Low photosynthetic rates and stomatal conductance of the cuttings during rooting were associated with water stress. The relationship between photosynthetic rates of such cuttings and cytokinin (CK) or ABA content was unclear. Chemical names used: [S-(Z,E]-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2, 4-pentadienoic acid (abscisic acid, ABA); 2-methyl-4-(1H-purin-6-ylamino)-2-buten-1-ol (zeatin, Z).

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