Stem Water Potential is a Sensitive Indicator of Grapevine Water Status

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.

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Towards Vine Water Status Monitoring on a Large Scale Using Sentinel-2 Images

Remote Sensing ◽

10.3390/rs13091837 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1837

Author(s):

Eve Laroche-Pinel ◽

Sylvie Duthoit ◽

Mohanad Albughdadi ◽

Anne D. Costard ◽

Jacques Rousseau ◽

...

Keyword(s):

Climate Change ◽

Water Potential ◽

Large Scale ◽

Water Status ◽

Vegetation Indices ◽

Machine Learning Algorithms ◽

Severe Drought ◽

Stem Water Potential ◽

Stem Water ◽

Sentinel 2

Wine growing needs to adapt to confront climate change. In fact, the lack of water becomes more and more important in many regions. Whereas vineyards have been located in dry areas for decades, so they need special resilient varieties and/or a sufficient water supply at key development stages in case of severe drought. With climate change and the decrease of water availability, some vineyard regions face difficulties because of unsuitable variety, wrong vine management or due to the limited water access. Decision support tools are therefore required to optimize water use or to adapt agronomic practices. This study aimed at monitoring vine water status at a large scale with Sentinel-2 images. The goal was to provide a solution that would give spatialized and temporal information throughout the season on the water status of the vines. For this purpose, thirty six plots were monitored in total over three years (2018, 2019 and 2020). Vine water status was measured with stem water potential in field measurements from pea size to ripening stage. Simultaneously Sentinel-2 images were downloaded and processed to extract band reflectance values and compute vegetation indices. In our study, we tested five supervised regression machine learning algorithms to find possible relationships between stem water potential and data acquired from Sentinel-2 images (bands reflectance values and vegetation indices). Regression model using Red, NIR, Red-Edge and SWIR bands gave promising result to predict stem water potential (R2=0.40, RMSE=0.26).

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Estimation water status of the vineyard by calculating multispectral index from satellite images

10.5194/egusphere-egu21-2187 ◽

2021 ◽

Author(s):

Marta Rodríguez-Fernández ◽

María Fandiño ◽

Xesús Pablo González ◽

Javier J. Cancela

Keyword(s):

Water Stress ◽

Water Potential ◽

Spectral Index ◽

Satellite Images ◽

Irrigation System ◽

Water Status ◽

Stress Index ◽

Stem Water Potential ◽

Stem Water ◽

Water Potential Measurements

The estimation of the water status in the vineyard, is a very important factor, in which every day the winegrowers show more interest since it directly affects the quality and production in the vineyards. The situation generated by COVID-19 in viticulture, adds importance to tools that provide information of the hydric status of vineyard plants in a telematic way.In the present study, the stem water potential in the 2018 and 2019 seasons, is analysed in a vineyard belonging to the Rias Baixas wine-growing area (Vilagarcia de Arousa, Spain), with 32 sampling points distributed throughout the plot, which allows the contrast and validation with the remote sensing methodology to estimate the water status of the vineyard using satellite images.The satellite images have been downloaded from the Sentinel-2 satellite, on the closets available dates regarding the stem water potential measurements, carried out in the months of June to September, because this dates are considered the months in which vine plants have higher water requirements.With satellite images, two spectral index related to the detection of water stress have been calculated: NDWI (Normalized Difference Water Index) and MSI (Moisture Stress Index). Stem water potential measurements, have allowed a linear regression with both index, to validate the use of these multispectral index to determine water stress in the vineyard.Determination coefficients of r2=0.62 and 0.67, have been obtained in July and August 2018 and 0.54 in June of 2019 for the NDWI index, as well as values of 0.53 and 0.63 in July 2018 and June 2019 respectively, when it has been analysed the MSI index.Between both seasons, the difference observed, that implies slightly greater water stress in 2019, is reflected in the climate conditions during the summer months, with an average accumulated rainfall that doesn&#8217;t exceed 46 mm of water. Although, the NDWI index has allowed to establish better relationships in the 2018 season respect to the MSI index and the 2019 season, (r2=0.60 NDWI in 2018), as well as greater differences in terms of water stress presented in the vineyard.With the spectral index calculated, it has been possible to validate the use of these index for the determination of the water stress of the vineyard plants, as an efficient, fast and less expensive method, which allows the application of an efficient irrigation system in the vineyard.

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Microtensiometers Accurately Measure Stem Water Potential in Woody Perennials

Plants ◽

10.3390/plants10122780 ◽

2021 ◽

Vol 10 (12) ◽

pp. 2780

Author(s):

Victor Blanco ◽

Lee Kalcsits

Keyword(s):

Water Potential ◽

Leaf Gas Exchange ◽

Water Status ◽

Full Range ◽

Canopy Temperature ◽

Plant Water ◽

Stem Water Potential ◽

Woody Tissue ◽

Woody Perennials ◽

Stem Water

Stem water potential (Ψstem) is considered to be the standard measure of plant water status. However, it is measured with the pressure chamber (PC), an equipment that can neither provide continuous information nor be automated, limiting its use. Recent developments of microtensiometers (MT; FloraPulse sensors), which can continuously measure water tension in woody tissue of the trunk of the tree, can potentially highlight the dynamic nature of plant water relations. Thus, this study aimed to validate and assess the usefulness of the MT by comparing the Ψstem provided by MT with those same measurements from the PC. Here, two irrigation treatments (a control and a deficit treatment) were applied in a pear (Pyrus communis L.) orchard in Washington State (USA) to capture the full range of water potentials in this environment. Discrete measurements of leaf gas exchange, canopy temperature and Ψstem measured with PC and MT were made every two hours for four days from dawn to sunset. There were strong linear relationships between the Ψstem-MT and Ψstem-PC (R2 > 0.8) and with vapor pressure deficit (R2 > 0.7). However, Ψstem-MT was more variable and lower than Ψstem-PC when Ψstem-MT was below −1.5 MPa, especially during the evening. Minimum Ψstem-MT occurred later in the afternoon compared to Ψstem-PC. Ψstem showed similar sensitivity and coefficients of variation for both PC and MT acquired data. Overall, the promising results achieved indicated the potential for MT to be used to continuously assess tree water status.

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Modeling Stem Water Potential by Separating the Effects of Soil Water Availability and Climatic Conditions on Water Status in Grapevine (Vitis vinifera L.)

Frontiers in Plant Science ◽

10.3389/fpls.2019.01485 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 2

Author(s):

Bruno Suter ◽

Roberta Triolo ◽

David Pernet ◽

Zhanwu Dai ◽

Cornelis Van Leeuwen

Keyword(s):

Vitis Vinifera ◽

Water Potential ◽

Soil Water ◽

Water Availability ◽

Water Status ◽

Climatic Conditions ◽

Soil Water Availability ◽

Vitis Vinifera L ◽

Stem Water Potential ◽

Stem Water

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Partial rootzone drying improves almond tree leaf-level water use efficiency and afternoon water status compared with regulated deficit irrigation

Functional Plant Biology ◽

10.1071/fp10247 ◽

2011 ◽

Vol 38 (5) ◽

pp. 372 ◽

Cited By ~ 24

Author(s):

Gregorio Egea ◽

Ian C. Dodd ◽

María M. González-Real ◽

Rafael Domingo ◽

Alain Baille

Keyword(s):

Gas Exchange ◽

Water Potential ◽

Leaf Gas Exchange ◽

Water Status ◽

Stem Water Potential ◽

Regulated Deficit Irrigation ◽

Leaf Level ◽

Use Efficiency ◽

Stem Water ◽

Partial Rootzone Drying

To determine whether partial rootzone drying (PRD) optimised leaf gas exchange and soil–plant water relations in almond (Prunus dulcis (Mill.) D.A. Webb) compared with regulated deficit irrigation (RDI), a 2 year trial was conducted on field-grown trees in a semiarid climate. Five irrigation treatments were established: full irrigation (FI) where the trees were irrigated at 100% of the standard crop evapotranspiration (ETc); three PRD treatments (PRD70, PRD50 and PRD30) that applied 70, 50 and 30% ETc, respectively; and a commercially practiced RDI treatment that applied 50% ETc during the kernel-filling stage and 100% ETc during the remainder of the growth season. Measurements of volumetric soil moisture content in the soil profile (0–100 cm), predawn leaf water potential (Ψpd), midday stem water potential (Ψms), midday leaf gas exchange and trunk diameter fluctuations (TDF) were made during two growing seasons. The diurnal patterns of leaf gas exchange and stem water potential (Ψs) were appraised during the kernel-filling stage in all irrigation regimes. When tree water relations were assessed at solar noon, PRD did not show differences in either leaf gas exchange or tree water status compared with RDI. At similar average soil moisture status (adjudged by similar Ψpd), PRD50 trees had higher water status than RDI trees in the afternoon, as confirmed by Ψs and TDF. Although irrigation placement showed no effects on diurnal stomatal regulation, diurnal leaf net photosynthesis (Al) was substantially less limited in PRD50 than in RDI trees, indicating that PRD improved leaf-level water use efficiency.

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Does predawn water potential discern between irrigation treatments in Galician white grapevine cultivars?

OENO One ◽

10.20870/oeno-one.2014.48.2.1566 ◽

2014 ◽

Vol 48 (2) ◽

pp. 123 ◽

Cited By ~ 3

Author(s):

José Manuel Mirás-Avalos ◽

Emiliano Trigo-Córdoba ◽

Yolanda Bouzas-Cid

Keyword(s):

Water Potential ◽

Leaf Water Potential ◽

Water Status ◽

Irrigation Management ◽

Growing Season ◽

Climatic Conditions ◽

Leaf Water ◽

Diurnal Changes ◽

Stem Water Potential ◽

Stem Water

Aims: To evaluate the usefulness of predawn water potential (Ψpd) to assess the water status of Galician grapevine cultivars for irrigation purposes.Methods and results: Three Galician white grapevine cultivars (Albariño, Godello and Treixadura) were subjected to rain-fed and irrigation conditions during the 2013 growing season. Diurnal changes in leaf water potential (Ψl) were measured using a pressure chamber on days with high evapotranspiration demand. Stem water potential (Ψs) was measured at midday. Ψpd was not able to discriminate between treatments, whereas Ψl and Ψs at midday were able to detect significant differences in water status among plants.Conclusion: Ψpd was not useful to evaluate vine water status under the Galician climatic conditions. In contrast, both Ψl and Ψs were effective for detecting differences between treatments and can thus be used for irrigation management purposes.Significance and impact of the study: This is the first study evaluating water status of Galician grapevine cultivars. It also provides useful information about the strategy for its control through measurements of midday Ψl or Ψs.

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Correlations among Predawn Leaf, Midday Leaf, and Midday Stem Water Potential and their Correlations with other Measures of Soil and Plant Water Status in Vitis vinifera

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.127.3.448 ◽

2002 ◽

Vol 127 (3) ◽

pp. 448-454 ◽

Cited By ~ 143

Author(s):

L.E. Williams ◽

F.J. Araujo

Keyword(s):

Vitis Vinifera ◽

Water Potential ◽

Leaf Water Potential ◽

Leaf Gas Exchange ◽

Water Status ◽

Linear Regression Analysis ◽

Leaf Water ◽

Stem Water Potential ◽

Stem Water ◽

Water Potential Measurements

A study was conducted to compare three measurements of determining water status of grapevines (Vitis vinifera L.) in the field. Predawn leaf water potential (ΨPD), midday leaf water potential (Ψl), and midday stem water potential (Ψstem) were measured on `Chardonnay' and `Cabernet Sauvignon' grapevines grown in Napa Valley, California late in the 1999 growing season. Both cultivars had been irrigated weekly at various fractions (0, 0.5, and 1.0 for `Chardonnay' and 0, 0.5, 0.75, and 1.5 for `Cabernet') of estimated vineyard evapotranspiration (ETc) from approximately anthesis up to the dates of measurements. Predawn water potential measurements were taken beginning at 0330 hr and completed before sunrise. Midday Ψl and Ψstem measurements were taken only between 1230 and 1330 hr. In addition, net CO2 assimilation rates (A) and stomatal conductance to water vapor (gs) were also measured at midday. Soil water content (SWC) was measured in the `Chardonnay' vineyard using a neutron probe. Values obtained for ΨPD, Ψl, and Ψstem in this study ranged from about -0.05 to -0.8, -0.7 to -1.8, and -0.5 to -1.6 MPa, respectively. All three measurements of vine water status were highly correlated with one another. Linear regression analysis of Ψl and Ψstem versus ΨPD resulted in r2 values of 0.88 and 0.85, respectively. A similar analysis of Ψl as a function of Ψstem resulted in an r2 of 0.92. In the `Chardonnay' vineyard, all three methods of estimating vine water status were significantly (P < 0.01) correlated with SWC and applied amounts of water. Lastly, ΨPD, Ψl, and Ψstem were all linearly correlated with measurements of A and gs at midday. Under the conditions of this study, ΨPD, Ψl, and Ψstem represent equally viable methods of assessing the water status of these grapevines. They were all correlated similarly with the amount of water in the soil profile and leaf gas exchange as well as with one another.

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Determination of an efficient irrigation schedule for the cultivation of rose cv. Freedom under greenhouse conditions in Colombia

Agronomía Colombiana ◽

10.15446/agron.colomb.v32n1.40160 ◽

2014 ◽

Vol 32 (1) ◽

pp. 95-102 ◽

Cited By ~ 1

Author(s):

Jhon Jairo Arévalo ◽

Javier Enrique Vélez S. ◽

Diego Sebastiano Intrigliolo

Keyword(s):

Water Potential ◽

Water Status ◽

Irrigation Schedule ◽

Experimental Period ◽

Plant Water Status ◽

Base Line ◽

Plant Water ◽

Stem Water Potential ◽

Evaporative Demand ◽

Stem Water

An experiment on rose (Rosa sp.) cv. Freedom was performed in a greenhouse on the Bogota Plateau, Colombia, to identify an efficient irrigation regime for this crop. The tested treatments were based on three irrigation doses, applying different fractions of the estimated crop evapotranspiration (ETc), calculated using a class A evaporation tank: i) 100% ETc (ETc100), ii) 80% ETc (ETc80) and iii) 70% ETc (ETc70). During the entire experimental period, from mid-May to early September, the crop had a constant production of floral stems. In all of the irrigation treatments, the soil and plant water status were monitored using tensiometers and the midday stem water potential, respectively (ystem). In the fully irrigated roses, the actual water use was determined using a drainage lysimeter in order to obtain the local crop coefficients (Kc) by means of a water balance. From June to August, the obtained monthly Kc values varied between 1.10 and 1.26. Compared to the ETc100 treatment, 14.5 and 21.8% less water was applied in treatments ETc80 and ETc70, respectively. Despite this fact, no statistically significant differences were found among the treatments for rose production or quality. Finally, in the more irrigated roses, tight relationships between the stem water potential and vapor pressure deficit were obtained. The reported base-line equations can be used for predicting the optimum rose plant water status, depending on the environmental conditions. Overall, the reported results can be used for an efficient irritation schedule for rose crops under greenhouse conditions, using the local Kc and direct determinations of plant water status corrected for the evaporative demand.

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