Plant strategies for maximizing growth during water stress and subsequent recovery in Solanum melongena L. (eggplant)

Climate change is projected to increase the incidence of severe drought in many regions, potentially requiring selection for different traits in crop species to maintain productivity under water stress. In this study, we identified a suite of hydraulic traits associated with high productivity under water stress in four genotypes of S. melongena L. We also assessed the potential for recovery of this suite of traits from drought stress after re-watering. We observed that two genotypes, PHL 4841 and PHL 2778, quickly grew into large plants with smaller, thicker leaves and increasingly poor hydraulic status (a water-spender strategy), whereas PHL 2789 and Mara maintained safer water status and larger leaves but sacrificed large gains in biomass (a water-saver strategy). The best performing genotype under water stress, PHL 2778, additionally showed a significant increase in root biomass allocation relative to other genotypes. Biomass traits of all genotypes were negatively impacted by water deficit and remained impaired after a week of recovery; however, physiological traits such as electron transport capacity of photosystem II, and proportional allocation to root biomass and fine root length, and leaf area recovered after one week, indicating a strong capacity for eggplant to rebound from short-term deficits via recovery of physiological activity and allocation to resource acquiring tissues. These traits should be considered in selection and breeding of eggplant hybrids for future agricultural outlooks.

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Genome-Wide Identification and Transcriptional Regulation of Aquaporin Genes in Bread Wheat (Triticum aestivum L.) under Water Stress

Genes ◽

10.3390/genes9100497 ◽

2018 ◽

Vol 9 (10) ◽

pp. 497 ◽

Cited By ~ 3

Author(s):

José Madrid-Espinoza ◽

Nidia Brunel-Saldias ◽

Fernando Guerra ◽

Adelina Gutiérrez ◽

Alejandro del Pozo

Keyword(s):

Triticum Aestivum ◽

Water Stress ◽

Functional Divergence ◽

Expression Patterns ◽

Structure And Function ◽

Transcriptional Level ◽

Severe Drought ◽

Crop Species ◽

Intrinsic Protein ◽

And Function

Aquaporins (AQPs) are transmembrane proteins essential for controlling the flow of water and other molecules required for development and stress tolerance in plants, including important crop species such as wheat (Triticum aestivum). In this study, we utilized a genomic approach for analyzing the information about AQPs available in public databases to characterize their structure and function. Furthermore, we validated the expression of a suite of AQP genes, at the transcriptional level, including accessions with contrasting responses to drought, different organs and water stress levels. We found 65 new AQP genes, from which 60% are copies expanded by polyploidization. Sequence analysis of the AQP genes showed that the purifying selection pressure acted on duplicate genes, which was related to a high conservation of the functions. This situation contrasted with the expression patterns observed for different organs, developmental stages or genotypes under water deficit conditions, which indicated functional divergence at transcription. Expression analyses on contrasting genotypes showed high gene transcription from Tonoplast Intrinsic Protein 1 (TIP1) and 2 (TIP2), and Plasma Membrane Intrinsic Protein 1 (PIP1) and 2 (PIP2) subfamilies in roots and from TIP1 and PIP1 subfamilies in leaves. Interestingly, during severe drought stress, 4 TIP genes analyzed in leaves of the tolerant accession reached up to 15-fold the level observed at the susceptible genotype, suggesting a positive relationship with drought tolerance. The obtained results extend our understanding of the structure and function of AQPs, particularly under water stress conditions.

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Response to water stress of Italian alder seedlings from diverse geographic origins

Canadian Journal of Forest Research ◽

10.1139/x89-163 ◽

1989 ◽

Vol 19 (8) ◽

pp. 1071-1076 ◽

Cited By ~ 5

Author(s):

M. Borghetti ◽

S. Cocco ◽

M. Lambardi ◽

S. Raddi

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Leaf Area ◽

Water Status ◽

Net Photosynthesis ◽

Severe Drought ◽

Xylem Water Potential ◽

Drought Treatment ◽

Internal Water ◽

Response To Water

The morphological and physiological response to water stress was studied in 2-year-old potted Italian alder (Alnuscordata Loisel.) seedlings. Leaf area, transpiration, stomatal conductance, and xylem water potential were measured during May 1987 on seedlings from five geographic sources grown (i) with soil water content close to field capacity and (ii) with a severe drought. Significant differences in leaf area were found, at the end of the experiment, between drought-stressed and well-watered plants. As drought progressed, plants displayed a reduction of xylem water potentials and a decrease in stomatal conductance. However, transpiration did not stop completely, and seedlings were not able to maintain a favourable internal water status. Osmotic potentials for the undiluted cell sap, estimated from pressure–volume curves, were between −0.9 and −1.3 MPa. In June 1988, a similar experiment was carried out using seedlings from only one geographic source. A simultaneous decrease of transpiration, xylem potential, and net photosynthesis was observed in seedlings subjected to the drought treatment. During both experiments, a recovery of physiological parameters was observed, after rewatering. Some differences between provenances were detected. The provenance from Corsica showed the greatest sensitivity to water stress; a seed source from the province of Avellino (Campania, south Italy) was able to maintain a more favourable internal water status, as drought progressed.

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Citrus Irrigation Management

EDIS ◽

10.32473/edis-ss660-2017 ◽

2017 ◽

Vol 2017 (5) ◽

Author(s):

Davie Mayeso Kadyampakeni ◽

Kelly T. Morgan ◽

Mongi Zekri ◽

Rhuanito Ferrarezi ◽

Arnold Schumann ◽

...

Keyword(s):

Water Stress ◽

Physiological Activity ◽

Irrigation Management ◽

Fruit Size ◽

Irrigation Scheduling ◽

Leaf Expansion ◽

Tree Canopy ◽

Limiting Factor ◽

Irrigation Frequency ◽

Citrus Production

Water is a limiting factor in Florida citrus production during the majority of the year because of the low water holding capacity of sandy soils resulting from low clay and the non-uniform distribution of the rainfall. In Florida, the major portion of rainfall comes in June through September. However, rainfall is scarce during the dry period from February through May, which coincides with the critical stages of bloom, leaf expansion, fruit set, and fruit enlargement. Irrigation is practiced to provide water when rainfall is not sufficient or timely to meet water needs. Proper irrigation scheduling is the application of water to crops only when needed and only in the amounts needed; that is, determining when to irrigate and how much water to apply. With proper irrigation scheduling, yield will not be limited by water stress. With citrus greening (HLB), irrigation scheduling is becoming more important and critical and growers cannot afford water stress or water excess. Any degree of water stress or imbalance can produce a deleterious change in physiological activity of growth and production of citrus trees. The number of fruit, fruit size, and tree canopy are reduced and premature fruit drop is increased with water stress. Extension growth in shoots and roots and leaf expansion are all negatively impacted by water stress. Other benefits of proper irrigation scheduling include reduced loss of nutrients from leaching as a result of excess water applications and reduced pollution of groundwater or surface waters from the leaching of nutrients. Recent studies have shown that for HLB-affected trees, irrigation frequency should increase and irrigation amounts should decrease to minimize water stress from drought stress or water excess, while ensuring optimal water availability in the rootzone at all times.

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Monitoring Crop Water Status and Irrigation Needs Using Multispectral Airborne Sensors

HortScience ◽

10.21273/hortsci.30.4.905d ◽

1995 ◽

Vol 30 (4) ◽

pp. 905D-905

Author(s):

Thomas R. Clarke ◽

M. Susan Moran

Keyword(s):

Water Stress ◽

Near Infrared ◽

Water Status ◽

Canopy Cover ◽

Stress Index ◽

Crop Water ◽

Vegetative Cover ◽

Crop Water Stress Index ◽

Water Stress Index ◽

Subsurface Drip

Water application efficiency can be improved by directly monitoring plant water status rather than depending on soil moisture measurements or modeled ET estimates. Plants receiving sufficient water through their roots have cooler leaves than those that are water-stressed, leading to the development of the Crop Water Stress Index based on hand-held infrared thermometry. Substantial error can occur in partial canopies, however, as exposed hot soil contributes to deceptively warm temperature readings. Mathematically comparing red and near-infrared reflectances provides a measure of vegetative cover, and this information was combined with thermal radiance to give a two-dimensional index capable of detecting water stress even with a low percentage of canopy cover. Thermal, red, and near-infrared images acquired over subsurface drip-irrigated cantaloupe fields demonstrated the method's ability to detect areas with clogged emitters, insufficient irrigation rate, and system water leaks.

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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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Single hyperspectral bands are highly sensitive to water stress in adult mandarin trees

10.5194/egusphere-egu21-12594 ◽

2021 ◽

Author(s):

Pablo Berríos ◽

Abdelmalek Temnani ◽

Susana Zapata ◽

Manuel Forcén ◽

Sandra Martínez-Pedreño ◽

...

Keyword(s):

Water Stress ◽

Water Deficit ◽

Phase Ii ◽

Irrigation Water ◽

Water Status ◽

Irrigation Scheduling ◽

Plant Water Status ◽

Phase Iii ◽

Plant Water ◽

Severe Water Stress

Mandarin is one of the most important Citrus cultivated in Spain and the sustainability of the crop is subject to a constant pressure for water resources among the productive sectors and to a high climatic demand conditions and low rainfall (about 250 mm per year). The availability of irrigation water in the Murcia Region is generally close to 3,500 m3 per ha and year, so it is only possible to satisfy 50 - 60% of the late mandarin ETc, which requires about 5,500 m3 per ha. For this reason, it is necessary to provide tools to farmers in order to control the water applied in each phenological phase without promoting levels of severe water stress to the crop that negatively affect the sustainability of farms located in semi-arid conditions. Stem water potential (SWP) is a plant water status indicator very sensitive to water deficit, although its measurement is manual, discontinuous and on a small-scale. &#160;In this way, indicators measured on a larger scale are necessary to achieve integrating the water status of the crop throughout the farm. Thus, the aim of this study was to determine the sensitivity to water deficit of different hyperspectral single bands (HSB) and their relationship with the midday SWP in mandarin trees submitted to severe water stress in different phenological phases. Four different irrigation treatments were assessed: i) a control (CTL), irrigated at 100% of the ETc throughout the growing season to satisfy plant water requirements and three water stress treatments that were irrigated at 60% of ETc throughout the season &#8211; corresponding to the real irrigation water availability &#8211; except &#160;during: ii) the end of phase I and beginning of phase II (IS IIa), iii) the first half of phase II (IS IIb) and iv) phase III of fruit growth (IS III), which irrigation was withheld until values of -1.8 MPa of SWP or a water stress integral of 60 MPa day-1. When these threshold values were reached, the spectral reflectance values were measured between 350 and 2500 nm using a leaf level spectroradiometer to 20 mature and sunny leaves on 4 trees per treatment. Twenty-four HVI and HSB were calculated and a linear correlation was made between each of them with SWP, where the &#961;940 and &#961;1250 nm single bands reflectance presented r-Pearson values of -0.78** and -0.83***, respectively. Two linear regression curves fitting were made: SWP (MPa) = -11.05 &#8729; &#961;940 + 7.8014 (R2 =0.61) and SWP (MPa) = -13.043 &#8729; &#961;1250 + 8.9757 (R2 =0.69). These relationships were obtained with three different fruit diameters (35, 50 and 65 mm) and in a range between -0.7 and -1.6 MPa of SWP. Results obtained show the possibility of using these single bands in the detection of water stress in adult mandarin trees, and thus propose a sustainable and efficient irrigation scheduling by means of unmanned aerial vehicles equipped with sensors to carry out an automated control of the plant water status and with a suitable temporal and spatial scale to apply precision irrigation.

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The Role of Ectomycorrhizal Symbiosis in the Resistance of Forests to Water Stress

Outlook on Agriculture ◽

10.5367/000000000101293068 ◽

2000 ◽

Vol 29 (1) ◽

pp. 63-69 ◽

Cited By ~ 18

Author(s):

Jean Garbaye

Keyword(s):

Water Stress ◽

Sustainable Management ◽

Fine Roots ◽

Forest Ecosystems ◽

Water Status ◽

Forest Trees ◽

Direct Effects ◽

Ectomycorrhizal Symbiosis ◽

Protection Mechanisms

Forest trees live in enforced symbiosis with specialized fungi that form composite organs (ectomycorrhizas) with fine roots. This paper examines how this association contributes to the water status of trees and how it plays a major role in the protection mechanisms by which trees and forest stands resist drought-induced water stress. It shows how ectomycorrhizal symbiosis has both direct effects (at the uptake level) and indirect effects (at the regulation level) on the water status of trees. The facts presented are discussed in terms of forest adaptation to changing environmental conditions and the practical consequences for the sustainable management of forest ecosystems.

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Stomatal conductance and growth of five Alnusglutinosa clones in response to controlled water stress

Canadian Journal of Forest Research ◽

10.1139/x88-062 ◽

1988 ◽

Vol 18 (4) ◽

pp. 421-426 ◽

Cited By ~ 4

Author(s):

T. C. Hennessey ◽

E. M. Lorenzi ◽

R. W. McNew

Keyword(s):

Water Stress ◽

Stomatal Conductance ◽

Drought Tolerance ◽

Leaf Area ◽

Water Status ◽

Height Growth ◽

Plant Water ◽

Black Alder ◽

Severe Water Stress ◽

Progressive Water Stress

An experiment to quantify the response of unnodulated, fertilized European black alder (Alnusglutinosa (L.) Gaertn.) seedlings to progressive water stress showed contrasting drought tolerance among five clones, using stomatal conductance, leaf area, and height as indices of drought sensitivity. In particular, one rapidly growing clone (AG 8022-14) showed the ability to moderate changes in water stress more efficiently than the more slowly growing clones. After 30 days of moderate levels of water stress, clones that had higher stomatal conductance also had greater leaf area and height growth. Leaf area and height were both sensitive to plant water status, although no threshold of stress associated with a cessation of leaf area or height expansion was found even though stomatal conductance decreased to 0.05 cm s−1 under severe water stress.

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Water-Stress Influences on Three New Promising HLB-Tolerant Citrus Rootstocks

Horticulturae ◽

10.3390/horticulturae7100336 ◽

2021 ◽

Vol 7 (10) ◽

pp. 336

Author(s):

Lidia Aparicio-Durán ◽

Frederick G. Gmitter ◽

Juan M. Arjona-López ◽

Rocío Calero-Velázquez ◽

Áurea Hervalejo ◽

...

Keyword(s):

Water Stress ◽

Water Status ◽

Abiotic Factors ◽

Dry Weight ◽

Emerging Diseases ◽

Carrizo Citrange ◽

Citrus Rootstock ◽

Chlorophyll Index ◽

Stress Influences ◽

Water Treatments

Drought and flooding conditions are increasingly common abiotic factors that affect citrus crops in both the Mediterranean Basin and Florida. Furthermore, emerging diseases, such as Huanglongbing (HLB), are a potential risk for these crops in those producing areas. This study aimed to evaluate the behavior under water-stress treatments of three new citrus rootstocks (UFR-6, B11R5T60, and 2247 x 6070-02-2) with reported tolerance of HLB, comparing them with a common commercial citrus rootstock (Carrizo citrange). Four water conditions were established: Control, Medium Water Stress (MWS), Drought, and Flooding. Chlorophyll index (SPAD), growth in height, relative growth rate, biomass (fresh and dry weight) and plant water status were evaluated. Citru rootstock response were different for each genotype; Carrizo citrange was negatively affected by all water treatments in the chlorophyll index (SPAD) and biomass production. By contrast, UFR-6 showed a positive response in SPAD and growth under MWS and Drought, B11R5T60 displayed similar behavior to Control under all water stresses, and the response of 2247 x 6070-02-2 under MWS treatment was adequate but was not under Drought or Flooding conditions. Our study describes the behavior of these promising new citrus rootstocks against water stress; B11R5T60 exhibiting the best performance. These results can be useful for the citrus industry to address water-stress problems in these crops.

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