The Decrease of Leaf Dark Respiration during Water Stress Is Related to Leaf Non-Structural Carbohydrate Pool in Vitis vinifera L.

Dark respiration (Rd) is a fundamental plant process used to gain biomass and maintain plant physiological activity. It accounts for the metabolization of a large share of the carbon fixed by photosynthesis. However, Rd during conditions of severe plant water stress is still poorly understood. The decrease in leaf transpiration increases temperature, one of the most important drivers of leaf Rd. On the other hand, water stress decreases the pool of leaf carbohydrates, which are the most important substrate for respiration. The aim of the present work was to determine the impact of water shortage on leaf Rd in grapevine and understand the driving factors in modulating leaf Rd response under plant water stress conditions. Water stressed vines had lower Rd as the water shortage severity increased. Rd was correlated with leaf temperature in well-watered vines. Instead, in water stressed vines, Rd correlated with leaf soluble sugars. The decrease of leaf Rd in water stressed vines was due to the decrease of leaf non-structural carbohydrate that, under water stress conditions, exerted a limiting effect on Rd.

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Evaluation of Water Stress Impact on the Parameter Values in Stomatal Conductance Models Using Tower Flux Measurement of a Boreal Aspen Forest

Journal of Hydrometeorology ◽

10.1175/jhm-d-11-043.1 ◽

2012 ◽

Vol 13 (1) ◽

pp. 239-254 ◽

Cited By ~ 9

Author(s):

Shusen Wang

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Flux Measurement ◽

Relative Reduction ◽

Model Parameters ◽

Plant Water ◽

Plant Water Stress ◽

Aspen Forest ◽

Parameter Values ◽

The Impact

Abstract The impact of water stress on plant stomatal conductance (g) has been widely studied but with little consensus as to the processes governing its responses. The photosynthesis-driven stomatal conductance models usually employ constant model parameters and attribute the decrease of g from water stress to the reduction of leaf photosynthesis. This has been challenged by studies showing that the model parameter values decrease when the plant is under water stress. In this study, the impact of plant water stress on the parameter values in stomatal conductance models is evaluated using the approach recently developed by S. Wang et al. and the tower flux measurements at a Canadian boreal aspen forest. Results show that the slope parameter (α) in the stomatal conductance models decreases substantially with the development of plant water stress. The magnitude of this reduction is dependent on how plant water stress is represented. Overall, the relative reduction of α from its maximum value is 28% when soil water content decreases from 0.38 to 0.18 m3 m−3, and is 38% when Bowen ratio increases from 0.25 to 3.5. Equations for α correction to account for water stress impacts are proposed. Further studies on different ecosystems are necessary to quantify the parameter variations with water stress among different climate regions and plant species.

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Every cloud has a silver lining: Moderate plant water stress positively impacts development, immunity, and gut microbiota of a specialist herbivore

10.1101/411678 ◽

2018 ◽

Author(s):

E Rosa ◽

G Minard ◽

J Lindholm ◽

M Saastamoinen

Keyword(s):

Water Stress ◽

Host Plant ◽

Fungal Community ◽

Larval Performance ◽

Immune Gene ◽

Plant Water ◽

Microbial Composition ◽

Specialist Herbivore ◽

Plant Water Stress ◽

The Impact

AbstractThe ongoing global temperature rise has led to increasing frequency of drought events, negatively impacting vegetation and the living organisms relying on it. Extreme drought killing host plants can clearly reduce herbivore fitness, but the impact of moderate host plant water stress on insect herbivores can vary, and may even be beneficial. The Finnish Glanville fritillary butterfly (Melitaea cinxia) has faced reduced precipitation in recent years, which has impacted population dynamics. However, whether the negative effects depend on extreme desiccation killing the host plant or moderate drought impacting plant quality remains unclear. We assessed the performance of larvae fed on moderately water-stressed Plantago lanceolata in terms of growth, gut microbial composition and immune response. We found that larvae fed on water-stressed plants had better growth, a more heterogeneous bacterial community and a shifted fungal community in the gut, and up-regulated the expression of one candidate immune gene (pelle), whereas survival remained unaffected. Most of the measured traits showed considerable variation due to family structure. Our data suggest that in temperate regions moderate host plant water stress can positively shape resource acquisition of this specialized insect herbivore, potentially by increasing nutrient accessibility or concentration. Potentially, the better larval performance may be mediated by a shift of the microbiota on water-stressed plants, calling for further research especially on the understudied gut fungal community.

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Response of ungrafted and grafted grapevine cultivans and rootstocks (Vitis sp.) to water stress

OENO One ◽

10.20870/oeno-one.2007.41.2.853 ◽

2007 ◽

Vol 41 (2) ◽

pp. 85 ◽

Cited By ~ 3

Author(s):

Imene Toumi ◽

Wissal M'Sehli ◽

Soumaya Bourgou ◽

Neila Jallouli ◽

Asma Bensalem-Fnayou ◽

...

Keyword(s):

Water Stress ◽

Water Potential ◽

Dry Matter ◽

Soluble Sugars ◽

Water Shortage ◽

Stem Water Potential ◽

Matter Production ◽

Stem Water ◽

The Impact ◽

Progressive Water Stress

Aims: The responses of two Vitis vinifera cultivars (Cardinal and Superior Seedless) and two rootstocks (110R and SO4) to drought, the effect of grafting and the interactions of scion/rootstock were investigated.Methods and results: The vines were subjected to a progressive water stress in greenhouse controlled conditions. At the end of the water stress treatments, physiological analyses were carried out (stem water potential, dry matter production, soluble sugars, proline as well as ions Na+ and K+). Drought was expressed by the drop of the stem water potential in the stressed vines as compared to their controls. Furthermore, tolerance and sensitivity were linked to the accumulation of soluble sugars and proline as well as the equilibrium of K+ and Na+ in the leaves.Conclusion: When ungrafted, Cardinal was more tolerant to water stress than Superior Seedless. The grafted vines exhibited more vigour, moreover, the combination of Cardinal with SO4 and Superior Seedless with 110R revealed to be the advantageous associations under water stress.Significance and impact of study: This work has been carried out to investigate the differential responses of grapevine cultivars to drought stress and the impact of grafting under water shortage conditions.

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Grazing winter wheat relieves plant water stress and transiently enhances photosynthesis

Functional Plant Biology ◽

10.1071/fp10040 ◽

2010 ◽

Vol 37 (8) ◽

pp. 726 ◽

Cited By ~ 37

Author(s):

Matthew T. Harrison ◽

Walter M. Kelman ◽

Andrew D. Moore ◽

John R. Evans

Keyword(s):

Water Stress ◽

Leaf Area ◽

Water Status ◽

Leaf Water ◽

Plant Water ◽

Rubisco Activity ◽

Leaf Water Status ◽

Area Index ◽

Plant Water Stress ◽

The Impact

To model the impact of grazing on the growth of wheat (Triticum aestivum L.), we measured photosynthesis in the field. Grazing may affect photosynthesis as a consequence of changes to leaf water status, nitrogen content per unit leaf area (Na) or photosynthetic enzyme activity. While light-saturated CO2 assimilation rates (Asat) of field-grown wheat were unchanged during grazing, Asat transiently increased by 33–68% compared with ungrazed leaves over a 2- to 4-week period after grazing ended. Grazing reduced leaf mass per unit area, increased stomatal conductance and increased intercellular CO2 concentrations (Ci) by 36–38%, 88–169% and 17–20%, respectively. Grazing did not alter Na. Using a photosynthesis model, we demonstrated that the increase in Asat after grazing required an increase in Rubisco activity of up to 53%, whereas the increase in Ci could only increase Asat by up to 13%. Increased Rubisco activity was associated with a partial alleviation of leaf water stress. We observed a 68% increase in leaf water potential of grazed plants that could be attributed to reduced leaf area index and canopy evaporative demand, as well as to increased rainfall infiltration into soil. The grazing of rain-fed grain cereals may be tailored to relieve plant water stress and enhance leaf photosynthesis.

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HortNet417v1—A Deep-Learning Architecture for the Automatic Detection of Pot-Cultivated Peach Plant Water Stress

Sensors ◽

10.3390/s21237924 ◽

2021 ◽

Vol 21 (23) ◽

pp. 7924

Author(s):

Md Parvez Islam ◽

Takayoshi Yamane

Keyword(s):

Deep Learning ◽

Water Stress ◽

Plant Stress ◽

High Stress ◽

Classification Performance ◽

Stress Conditions ◽

Test Accuracy ◽

Plant Water ◽

Plant Water Stress ◽

Learning Techniques

The biggest challenge in the classification of plant water stress conditions is the similar appearance of different stress conditions. We introduce HortNet417v1 with 417 layers for rapid recognition, classification, and visualization of plant stress conditions, such as no stress, low stress, middle stress, high stress, and very high stress, in real time with higher accuracy and a lower computing condition. We evaluated the classification performance by training more than 50,632 augmented images and found that HortNet417v1 has 90.77% training, 90.52% cross validation, and 93.00% test accuracy without any overfitting issue, while other networks like Xception, ShuffleNet, and MobileNetv2 have an overfitting issue, although they achieved 100% training accuracy. This research will motivate and encourage the further use of deep learning techniques to automatically detect and classify plant stress conditions and provide farmers with the necessary information to manage irrigation practices in a timely manner.

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Leaf surface water, not plant water stress, drives diurnal variation in tropical forest canopy water content

New Phytologist ◽

10.1111/nph.17254 ◽

2021 ◽

Author(s):

Xiangtao Xu ◽

Alexandra G. Konings ◽

Marcos Longo ◽

Andrew Feldman ◽

Liang Xu ◽

...

Keyword(s):

Water Stress ◽

Surface Water ◽

Tropical Forest ◽

Diurnal Variation ◽

Forest Canopy ◽

Leaf Surface ◽

Plant Water ◽

Plant Water Stress ◽

Canopy Water ◽

Tropical Forest Canopy

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Leaf compatible “eco-friendly” temperature sensor clip for high density monitoring wireless networks

Wireless Power Transfer ◽

10.1017/wpt.2017.1 ◽

2017 ◽

Vol 4 (1) ◽

pp. 55-60 ◽

Cited By ~ 5

Author(s):

Valeria Palazzari ◽

Paolo Mezzanotte ◽

Federico Alimenti ◽

Francesco Fratini ◽

Giulia Orecchini ◽

...

Keyword(s):

Decision Support ◽

Water Stress ◽

Temperature Sensor ◽

Irrigation System ◽

Fuel Oil ◽

Plant Water ◽

Temperature Differential ◽

Water Pump ◽

Plant Water Stress ◽

System A

This paper describes the design, realization, and application of a custom temperature sensor devoted to the monitoring of the temperature differential between the leaf and the air. This difference is strictly related to the plant water stress and can be used as an input information for an intelligent and flexible irrigation system. A wireless temperature sensor network can be thought as a decision support system used to start irrigation when effectively needed by the cultivation, thus saving water, pump fuel oil, and preventing plant illness caused by over-watering.

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Reducing the Excessive Evaporative Demand Improved the Water-use Efficiency of Greenhouse Cucumber by Regulating the Trade-off between Irrigation Demand and Plant Productivity

HortScience ◽

10.21273/hortsci13129-18 ◽

2018 ◽

Vol 53 (12) ◽

pp. 1784-1790 ◽

Cited By ~ 4

Author(s):

Dalong Zhang ◽

Yuping Liu ◽

Yang Li ◽

Lijie Qin ◽

Jun Li ◽

...

Keyword(s):

Water Stress ◽

Water Use Efficiency ◽

Water Flow ◽

Water Use ◽

Plant Productivity ◽

Plant Water ◽

Evaporative Demand ◽

Plant Water Stress ◽

Irrigation Demand ◽

Use Efficiency

Although atmospheric evaporative demand mediates water flow and constrains water-use efficiency (WUE) to a large extent, the potential to reduce irrigation demand and improve water productivity by regulating the atmospheric water driving force is highly uncertain. To bridge this gap, water transport in combination with plant productivity was examined in cucumber (Cucumis sativus L.) grown at contrasting evaporative demand gradients. Reducing the excessive vapor pressure deficit (VPD) decreased the water flow rate, which reduced irrigation consumption significantly by 16.4%. Reducing excessive evaporative demand moderated plant water stress, as leaf dehydration, hydraulic limitation, and excessive negative water potential were prevented by maintaining water balance in the low-VPD treatment. The moderation of plant water stress by reducing evaporative demand sustained stomatal function for photosynthesis and plant growth, which increased substantially fruit yield and shoot biomass by 20.1% and 18.4%, respectively. From a physiological perspective, a reduction in irrigation demand and an improvement in plant productivity were achieved concomitantly by reducing the excessive VPD. Consequently, WUE based on the criteria of plant biomass and fruit yield was increased significantly by 43.1% and 40.5%, respectively.

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