Physiological and anatomical responses of wheat to induced dehydration and rehydration

AbstractHydroponically grown wheat seedlings of two prominent Bulgarian cultivars (Katya and Prelom) were subjected to 48 h osmotic stress with PEG 8000 and were then rehydrated. The degree of stress was evaluated by monitoring relative water content, lipid peroxidation level, and accumulation of free proline and hydrogen peroxide in the leaves. Anatomy and ultrastructure of leaf tissue were observed under light microscopy. After imposition of stress, drought tolerant cultivar Katya displayed higher free proline content and significantly lower malondialdehyde and peroxide concentration in leaves than in the leaves of susceptible cultivar Prelom. After 24 h of rehydration Katya showed better ability to restore leaf water status and an apparent tendency towards recovery, whereas Prelom sustained higher levels of hydrogen peroxide, lipid peroxidation products and free proline and markedly low relative water content. Here, we have uncovered some of the characteristics displayed by cultivar Katya that enable it to survive and recover from severe osmotic stress. Interestingly, there was congruence between our results and the high level of cultivar Katya drought tolerance observed in the field.

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Assessment of flag leaf water status as drought tolerance discriminating trait in durum wheat (Triticum turgidum var durum L.)

10.30574/msarr.2021.2.1.0026 ◽

2021 ◽

Vol 2 (1) ◽

pp. 016-027

Author(s):

Hadda Mebarki ◽

Ouassila Ziane ◽

Hadjer Merbah ◽

Hamenna Bouzerzour

Keyword(s):

Water Content ◽

Water Loss ◽

Relative Water Content ◽

Water Saturation ◽

Water Status ◽

Leaf Water ◽

Leaf Water Status ◽

Water Saturation Deficit ◽

Saturation Deficit ◽

Relative Water

Drought is a prominent limiting factor that impacts negatively durum wheat grain yield. Ten durum wheat breeding lines were evaluated under rainfall conditions at the Field Crop Institute Agricultural Experimental Station of Setif, Algeria, during the 2016/2017 cropping season. The investigation aimed to study the ability of flag leaf water status to discriminate among varieties for drought tolerance trait. Significant variability was observed among the tested varieties for leaf dry, wilted and turgid weights, leaf relative water content, water saturation deficit and excised water loss, after three wilting periods of 30, 60 and 90 minutes dehydration at 40°C. The assessed breeding lines were differentially categorized as drought tolerant and drought sensitive based on either relative water content or water saturation deficit or excised leaf water loss genotypic mean values. Correlation, principal components and cluster analyses indicated an unwanted significant association between excised leaf water loss and relative water content and water saturation deficit and classified the assessed entries into three clusters (CI, C2 and C3). Cluster C1 had high relative water content, low water saturation deficit but high excised water loss, while C3 had low relative water content, low excised leaf water but high-water saturation deficit, C2 being intermediate. Crosses between distant clusters (C1 vs C3) are proposed to generate more variability of the targeted traits in progeny population and to break undesirable linkage between alleles controlling leaf water status, allowing to select efficiently drought tolerant genotypes.

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The Method of Plant Water Status Measurement in Sweet Potato (Ipomoea Batatas (L) Lam.)

Beccariana Botanical Research Bulletin ◽

10.30862/bbrp.v7i1.274 ◽

2010 ◽

Vol 7 (1) ◽

Author(s):

Saraswati Prabawardani

Keyword(s):

Water Content ◽

Sweet Potato ◽

Relative Water Content ◽

Water Status ◽

Plant Water Status ◽

Equilibration Time ◽

Plant Water ◽

Font Size ◽

Potato Leaf ◽

Relative Water

The measurement of plant water status such as leaf water potential (LWP) and leaf relative water content (RWC) is important part of understanding plant physiology and biomass production. Preliminary study was made to determine the optimum amount of leaf abrasion and equilibration time of sweet potato leaf inside the thermocouple psychrometer chambers. Based on the trial, the standard equilibration time curve of a Peltier thermocouple for sweet potato leaf was between 2 and 3 hours. To increase the water vapour conductance across the leaf epidermis the waxy leaf cuticle should be removed or broken by abrasion. The result showed that 4 times leaf rubbings was accepted as the most effective way to increase leaf vapour conductance of sweet potato in the psychrometer chambers. In calculating the leaf relative water content, unstressed water of sweet potato leaves require 4 hours imbibition, whereas water stressed of sweet potato leaves require 5 to 6 hours to reach the saturation time. Either leaf water potential or relative water content can be used as a parameter for plant water status in sweet potato.

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Relative water content consistently predicts drought mortality risk in seedling populations with different morphology, physiology, and times to death

10.1101/2020.12.08.416917 ◽

2020 ◽

Author(s):

Gerard Sapes ◽

Anna Sala

Keyword(s):

Water Content ◽

Real Time ◽

Pinus Ponderosa ◽

Mortality Risk ◽

Relative Water Content ◽

Large Scale ◽

Water Status ◽

Physiological Indicators ◽

Relative Water ◽

Global Impacts

AbstractPredicted increases in forest drought mortality highlight the need for predictors of incipient drought-induced mortality (DIM) risk that enable proactive large-scale management. Such predictors should be consistent across plants with varying morphology and physiology. Because of their integrative nature, indicators of water status are promising candidates for real time monitoring of DIM, particularly if they standardize morphological differences among plants. We assessed the extent to which differences in morphology and physiology between Pinus ponderosa populations influence time to mortality and the predictive power of key indicators of DIM risk. Time to incipient mortality differed between populations but occurred at the same relative water content (RWC) and water potential (WP). RWC and WP were more accurate predictors of drought mortality risk than other physiological indicators, including non-structural carbohydrate (NSC) content and percent loss of conductivity (PLC). These results highlight that variables related to water status capture critical thresholds during DIM and the associated dehydration processes. Both WP and RWC are promising candidates for large-scale assessments of DIM risk. RWC is of special interest because it allows comparisons across different morphologies and can be remotely sensed. Our results offer promise for real time landscape-level monitoring of DIM and its global impacts.

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Multiple stresses on the oxidative metabolism of sugarcane varieties

Ciência Rural ◽

10.1590/0103-8478cr20141487 ◽

2018 ◽

Vol 48 (4) ◽

Cited By ~ 5

Author(s):

Marciana Bizerra de Morais ◽

Terezinha Rangel Camara ◽

Cláudia Ulisses ◽

José Luiz Sandes Carvalho Filho ◽

Lilia Willadino

Keyword(s):

Lipid Peroxidation ◽

Water Content ◽

Relative Water Content ◽

Defense Mechanisms ◽

Redox System ◽

Antioxidant Response ◽

High Temperature Stress ◽

Saline Stress ◽

Multiple Stresses ◽

Relative Water

ABSTRACT: The exposure of plants to multiple stress conditions can cause over production of reactive oxygen species promoting an imbalance in the redox system. The aim of this study was to examine the antioxidant response from varieties of sugarcane under adverse conditions, to understand the defense mechanisms of tolerant and sensitive genotypes. Micropropagated sugarcane of six genotypes, RB966928, RB98710, RB855453, RB99395, RB867515, and RB855156, were subjected to isolated action of high-temperature stress and a combination of water and saline stress, and effects were evaluated. Activities of enzymes such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), as well as stress indicators such as lipid peroxidation (MDA content) and hydrogen peroxide (H2O2) content were evaluated. The RB867515 variety showed synchrony between the enzymatic activity and ROS regulation and detoxification, in the plant cell under environmental stress situations, thereby ensuring the maintenance of the relative water content without increment of lipid peroxidation; and consequently, the maintenance of physiological processes and plant growth. These results indicated that lipid peroxidation associated with relative water content can be good biochemical markers of sensitivity to multiple stresses in sugarcane.

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Increased drought resistance of black locust seedlings via pretreatment of seeds with paclobutrazol

Canadian Journal of Forest Research ◽

10.1139/x93-315 ◽

1993 ◽

Vol 23 (12) ◽

pp. 2548-2551 ◽

Cited By ~ 2

Author(s):

Shen Hui-Juan ◽

Zeng Bin

Keyword(s):

Osmotic Stress ◽

Water Content ◽

Drought Resistance ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Black Locust ◽

Cellular Stress ◽

Relative Water

The drought resistance of black locust (Robiniapseudoacacia L.) seedlings was increased by pretreatment of seeds with 250 ppm paclobutrazol. Treated seeds produced seedlings with thick roots and higher root/shoot ratios. During osmotic stress, treated plants displayed greater relative water content, lower electrolyte leakage, and fewer symptoms of wilt when compared with untreated black locust seedlings. Paclobutrazol-treated seedlings accumulated more proline than untreated seedlings in response to drought. However, osmotically induced accumulation of putrescine, a possible marker of cellular stress, was reduced in the treated plants.

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Capillary Mats Alter the Water Content in Medium during Mist Propagation of Dendranthema

HortScience ◽

10.21273/hortsci.39.3.584 ◽

2004 ◽

Vol 39 (3) ◽

pp. 584-587 ◽

Cited By ~ 1

Author(s):

R.L. Geneve ◽

S.T. Kester ◽

J.W. Buxton

Keyword(s):

Water Content ◽

Water Table ◽

Relative Water Content ◽

Water Status ◽

Internal Water ◽

Relative Water ◽

Reduced Water ◽

Water Contents

A capillary mat-mist system was developed to provide near constant media water contents at differing quantities of mist. Media water contents were reduced by increasing the capillary mat height above a constant water table maintained at bench level. Increased tensions from 0 to 10 cm above the water table reduced water content in Oasis, rockwool, and peat-perlite by 35.4%, 27.6%, and 17.4%, respectively. There was no difference in water content for each medium when the mist quantity ranged between 600 and 1800 mL·m-2·h-1, except when the capillary mat was at 9 cm above the water table and mist volume was 300 mL·m-2·h-1. Chrysanthemum cuttings rooted best when water content was highest regardless of media. Using the peat-perlite medium, water content had the greatest impact on rooting when the mist volume was low (600 mL·m-2·h-1). Relative water content of cuttings was lowest during the first 5 days of sticking and both reduced media water content and mist quantity resulted in the lowest internal water status for the cuttings.

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EFEITOS DO DÉFICIT HÍDRICO EM PARÂMETROS FISIOLÓGICOS DE FOLHAS DE SORGO (Sorghum bicolor, L.)

Irriga ◽

10.15809/irriga.1998v3n3p81-88 ◽

1998 ◽

Vol 3 (3) ◽

pp. 81-88

Author(s):

Carlos Augusto Lima Porto ◽

Antonio Evaldo Klar ◽

José Vicente Vasconcelos

Keyword(s):

Water Stress ◽

Sorghum Bicolor ◽

Water Potential ◽

Water Content ◽

Relative Water Content ◽

Water Status ◽

Soil Water Potential ◽

Relative Water ◽

Conductivity Water ◽

Sorghum Bicolor L

EFEITOS DO DÉFICIT HÍDRICO EM PARÂMETROS FISIOLÓGICOS DE FOLHAS DE SORGO (Sorghum bicolor, L.) Carlos Augusto Lima PortoAntonio Evaldo Klar(2)José Vicente VasconcelosDepartamento de Engenharia Rural – Faculdade de Ciências Agronômicas – UNESPFone: (014) 821-3883 Fax: (014) 821-343818603-97’ – Botucatu - SP 1 RESUMO O experimento foi conduzido em casa de vegetação no Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas - UNESP/Botucatu, SP, com delineamento experimental inteiramente casualizado, com 12 repetições. A cultura do sorgo (Sorghum bicolor, L.) foi plantada em vasos que continham 8,0 kg de solo (base em peso de solo seco), pertencente ao grande grupo Terra Roxa Estruturada para os dois tratamentos: a) plantas submetidas a défices hídricos, sendo irrigadas quando o potencial de água no solo chegava a -1,5 MPa, elevando-o às imediações de -0,01 MPa), e b) plantas irrigadas constantemente por capilaridade. Todas as plantas foram irrigadas aos 55 dias após a emergência e os parâmetros avaliados foram: condutância estomática, potencial de água e teor relativo de água nas folhas mais novas totalmente expandidas, com determinações diárias entre as onze e treze horas, até que o potencial de água no solo atingisse valores em torno de -1,5 MPa. Da análise geral dos dados obtidos, pode-se inferir que a variação no status de água na folha observado através do potencial e do teor relativo de água nas folhas pode ser utilizado para indicar o momento de irrigar; ainda estas medições podem ser indicativas das plantas ou cultivares de sorgo que se mostram mais tolerantes à seca e que o mecanismo de adaptação é o “avoidance”. UNITERMOS: Condutividade estomática, potencial de água na folha, teor relativo de água na folha, tolerância à seca. PORTO, C. A . L.., KLAR, A. E. , VASCONCELLOS, V. J. Water deficit on physiological parameters of soybean leaves (Sorghum bicolor L). 2 ABSTRACT A study was carried out at Agricultural Engineering Department, UNESP, Botucatu - SP, with a sorghum crop (Sorghum bicolor, L.) in order to physiologically evaluate the crop response to drought. A completely random design with twelve replications were used. Pots with 8 kg of a medium texture soil (dry weight basis) were used in order to test the influence of the two treatments: a) plants being submitted to a water stress, where irrigation were done when the water potential in the soil (s) were -1,5 MPa, raising it to about -0,01 MPa, and b) plants being always irrigated by capillary. The parameters evaluated were water vapor stomata conductivity, water potential and relative water content in the leaves. All plants were irrigated at 55 days after emergency, with daily determinations from eleven AM to thirteen PM, until soil water potential reaches around -1,5MPa. From the general data analysis, it can be inferred that there was a significant variation in the water status in the leaves by determinations of water potential and relative water content in the leaves, indicating that the method may be used to indicate the moment of irrigation and the plants and cultivars more tolerant to drought. Sorghum plants showed adaptation to water stress under avoidance mechanism. KEYWORDS: Stomata conductivity, water potential in the leaves, relative water content, drought tolerance.

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EFFECT OF PEG INDUCED OSMOTIC STRESS ON PROLINE, PROTEIN AND RELATIVE WATER CONTENT IN IN VITRO PLANTS OF MACROTYLOMA UNIFLORUM (LAM.) VERDC.

Acta Horticulturae ◽

10.17660/actahortic.2010.865.10 ◽

2010 ◽

pp. 87-93 ◽

Cited By ~ 1

Author(s):

D.H. Tejavathi ◽

V.R. Devaraj ◽

S.M. Murthy ◽

R. Nijagunaiah ◽

K. Shobha

Keyword(s):

Osmotic Stress ◽

Water Content ◽

Relative Water Content ◽

In Vitro Plants ◽

Macrotyloma Uniflorum ◽

Relative Water

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Beneficial Effects of Biochar and Chitosan on Antioxidative Capacity, Osmolytes Accumulation, and Anatomical Characters of Water-Stressed Barley Plants

Agronomy ◽

10.3390/agronomy10050630 ◽

2020 ◽

Vol 10 (5) ◽

pp. 630 ◽

Cited By ~ 5

Author(s):

Yaser Hafez ◽

Kotb Attia ◽

Salman Alamery ◽

Abdelhalim Ghazy ◽

Abdullah Al-Doss ◽

...

Keyword(s):

Lipid Peroxidation ◽

Drought Stress ◽

Water Content ◽

Plant Height ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Relative Water ◽

Number Of Leaves ◽

The Impact ◽

Chlorophyll Concentrations

The impact of biochar and chitosan on barley plants under drought stress conditions was investigated during two field experiments. Our results confirmed that drought stress negatively affected morphological and physiological growth traits of barley plants such as plant height, number of leaves, chlorophyll concentrations, and relative water content. However, electrolyte leakage (EL%), lipid peroxidation (MDA), soluble sugars, sucrose and starch contents significantly increased as a response to drought stress. Additionally, 1000 grain weight, grains yield ha−1 and biological yield significantly decreased in stressed barley plants, also anatomical traits such as upper epidermis, lower epidermis, lamina, and mesophyll tissue thickness as well as vascular bundle diameter of flag leaves significantly decreased compared with control. The use of biochar and chitosan led to significant increases in plant height, number of leaves, and chlorophyll concentrations as well as relative water content; nevertheless these treatments led to significant decreases in electrolyte leakage (EL%) and lipid peroxidation (MDA) in the stressed plants. Moreover, anatomical and yield characters of stressed barley plants were improved with application of biochar and chitosan. The results proved the significance of biochar and chitosan in alleviating the damaging impacts of drought on barley plants.

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Water relations and yield inAzospirillum-inoculated wheat exposed to drought in the field

Canadian Journal of Botany ◽

10.1139/b03-119 ◽

2004 ◽

Vol 82 (2) ◽

pp. 273-281 ◽

Cited By ~ 152

Author(s):

Cecilia M Creus ◽

Rolando J Sueldo ◽

Carlos A Barassi

Keyword(s):

Grain Yield ◽

Water Potential ◽

Water Content ◽

Water Relations ◽

Relative Water Content ◽

Mineral Content ◽

Water Status ◽

Water Fraction ◽

Relative Water ◽

And Control

There are scarce data connecting water relations in Azospirillum-inoculated wheat suffering drought during anthesis with the yield and mineral content of grains. Azospirillum brasilense Sp245-inoculated seeds of Triticum aestivum 'Pro INTA Oasis' were sown in nonirrigated and control plots. Water potential, water content, and relative water content were determined on flag leaves. Plant water status was calculated from pressurevolume curves. At maturity, grain yield and its components were determined. P, Ca, Mg, K, Fe, Cu, and Zn were determined in dried grains. Even though the cultivar underwent osmotic adjustment, significantly higher water content, relative water content, water potential, apoplastic water fraction, and lower cell wall modulus of elasticity values were obtained in Azospirillum-inoculated plants suffering drought. Grain yield loss to drought was 26.5% and 14.1% in noninoculated and Azospirillum-inoculated plants, respectively. Grain Mg and K diminished in nonirrigated, noninoculated plots. However, grains harvested from Azospirillum-inoculated plants had significantly higher Mg, K, and Ca than noninoculated plants. Neither drought nor inoculation changed grain P, Cu, Fe, and Zn contents. A better water status and an additional "elastic adjustment" in Azospirillum-inoculated wheat plants could be crucial in promoting higher grain yield and mineral quality at harvest, particularly when drought strikes during anthesis.Key words: Azospirillum, wheat, drought, pressurevolume curves, yield, mineral content.

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