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

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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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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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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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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Reliability of leaf relative water content (RWC) measurements after storage: consequences for in situ measurements

Botany ◽

10.1139/cjb-2015-0065 ◽

2015 ◽

Vol 93 (9) ◽

pp. 535-541 ◽

Cited By ~ 17

Author(s):

Fallon M. Tanentzap ◽

Alexandra Stempel ◽

Peter Ryser

Keyword(s):

Water Content ◽

Relative Water Content ◽

Storage Temperature ◽

Water Status ◽

Plastic Bags ◽

Duration Of Storage ◽

Relative Water ◽

Leaf Relative Water Content ◽

Species Specific

Relative water content (RWC) is widely used to describe plant water status, and is commonly measured gravimetrically. The ephemeral nature of leaf fresh mass poses severe constraints for such measurements in field-grown plants. These constraints can be overcome by transporting the leaves in waterproof containers into the lab. However, even then, leaves lose water, and other changes may happen. The effects of a delay on the measurement of RWC have not been quantified so far. In this study, the influence of duration of storage up to 96 h and storage temperature on RWC and its components was investigated for four species. Alnus incana subsp. rugosa (Du Roi) R.T. Clausen, Impatiens capensis Meerb., and Scirpus microcarpus J.Presl & C.Presl leaves were stored in plastic bags, whereas those of Comptonia peregrina (L.) J.M.Coult. were stored in plastic vials. RWC remained within 5% of the initial value during 24 h cool storage, but after that, larger changes were observed. The effects of storage were species specific, being most pronounced in species poorly protected against desiccation, and under warm conditions. The effects of storage were not only limited to water loss, but also included cellular degradation. In general, storage at 10 °C for 24 h enables measurement of RWC for field-grown plants with accuracy of a few percent, but care has to be taken with species vulnerable to desiccation, possibly requiring faster measurement and a cooler storage temperature.

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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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Effect of Irrigation Regimes on the Water Status, Vegetative Growth and Rubber Production of Guayule Plants

Experimental Agriculture ◽

10.1017/s0014479700016690 ◽

1989 ◽

Vol 25 (2) ◽

pp. 189-197 ◽

Cited By ~ 7

Author(s):

Aliza Benzioni ◽

David Mills ◽

Meir Forti

Keyword(s):

Water Content ◽

Soil Water ◽

Relative Water Content ◽

Water Status ◽

Biomass Accumulation ◽

High Water ◽

Parthenium Argentatum ◽

Irrigation Regimes ◽

Relative Water ◽

Use Efficiency

SUMMARYThree irrigation regimes (250, 450, 650 mm year−1) were applied to guayule (Parthenium argentatum), a rubber-producing plant, in such a way as to provide periods of good soil water status alternating with periods of water stress. The relative water content and transpiration rate of the plants decreased only when the available soil water was depleted to about 40%. Very low values (< 30%) were measured for the relative water content. Water-stressed plants recovered as soon as irrigation was resumed. Growth and biomass accumulation, as well as the yields of rubber and resins, were directly related to the irrigation rates. The water regimes applied and the use of the drip irrigation method resulted in a relatively high water use efficiency.

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Effects of dehydration and rehydration on the leaf lipids and lipid metabolism in Parkinsonia aculeata (Caesalpiniaceae)

Botany ◽

10.1139/cjb-2013-0028 ◽

2013 ◽

Vol 91 (8) ◽

pp. 505-513 ◽

Cited By ~ 5

Author(s):

Ali Benadjaoud ◽

Ghouziel Benhassaine-Kesri ◽

Alain Zachowski ◽

Fatiha Aïd

Keyword(s):

Water Content ◽

Relative Water Content ◽

Membrane Lipids ◽

Neutral Lipids ◽

Water Status ◽

Stress Relief ◽

Dry Mass ◽

Slight Variation ◽

Parkinsonia Aculeata ◽

Relative Water

Plants of Parkinsonia aculeata L. were dehydrated by withholding water for 13 days and then rehydrated. The leaves of control plants and stressed plants were analyzed every four days from the beginning of stress and 6, 24, and 48 h after stress relief. Analysis of leaf water status showed a decrease in relative water content of nearly 16% during dehydration and a return to its control value after 48 h of rehydration. The contents of chlorophylls, chloroplast lipids (monogalactosyldiacylglycerol and digalactosyldiacylglycerol), and neutral lipids increased by 38%, 20%, and 125% (in μg·mg dry mass−1), respectively, when the daily decrease of relative water content reached 1.4%, while the mass of extra-plastidial lipids (phosphatidylcholine and phosphatidylethanolamine) increased by 25% (in μg·mg dry mass−1) only when the daily water loss was 2.6%. In addition, incorporation of radioactive acetate in lipids showed a preferential synthesis of digalactosyldiacylglycerol, phosphatidylglycerol, and phosphatidylcholine. The unsaturation degree of galactolipids remained stable, while a slight increase of unsaturation of phosphatidylcholine and phosphatidylethanolamine was observed. After rehydration, the mass of chlorophylls fell sharply, while the amount of total lipids decreased slowly as the level remained 17% higher than in the control 6 h after stress relief. Our results show that Parkinsonia plants are sensitive to a slight variation of the water potential and respond with an increased synthesis of membrane lipids during stress and after rehydration.

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Effects of Sodium Chloride Salinity on Water Relations and Ion Accumulation in Two Mungbean Varieties Differing in Salinity Tolerance

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v45i1.46569 ◽

2019 ◽

Vol 45 (1) ◽

pp. 45-54

Author(s):

Mst Shahnaz Sultana ◽

MA Halim ◽

Feroza Hossain ◽

M Abdul Karim ◽

Mohammad Talim Hossain

Keyword(s):

Salt Tolerance ◽

Water Content ◽

Relative Water Content ◽

Water Saturation ◽

Water Status ◽

Water Saturation Deficit ◽

Saturation Deficit ◽

Plant Parts ◽

Relative Water ◽

Exudation Rate

Salt tolerance in relation to water status and plant nutrients of two mungbean varieties, BARImung 2 (salinity sensitive) and BUmung 2 (salinity tolerant) was evaluated. The seeds were grown in pots and treated with NaCl levels of 0 (control), 100 and 200 mM. Different parameters related to water relations as well as mineral nutritients were measured. The exudation rate and relative water content were decreased but water saturation deficit was increased by salinity in both the varieties. In BARImung 2 plants, the exudation rate and relative water content were lower but water saturation deficit was higher than those in BUmung 2 at both 100 and 200 mM NaCl levels. Salinity also influenced the accumulation of Na, K, Ca and Mg in leaves, stems and roots of the two said mungbean varieties. Sodium accumulation was inceseased in all the plant-parts of both the varieties in the order of stem > root > leaf but in BUmung 2 the accumulation was lower than that of BARImung 2 except in root. Potassium accumulation deceresed in all parts of both the mungbean varieties but that was lower in BUmung 2 than that of BARImung 2. The contents of Ca and Mg in all the plant-parts increased more in BUmung 2 than those of BARImung 2 with the increase of salinity levels. All these results indicated that high salt tolerance in BUmung 2 was associated with its better water status, more or less uniform mineral nutrient (Ca and Mg) distribution in different plantparts than that in BARImung 2. Asiat. Soc. Bangladesh, Sci. 45(1): 45-54, June 2019

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Physiological and anatomical responses of wheat to induced dehydration and rehydration

Open Life Sciences ◽

10.2478/s11535-013-0153-x ◽

2013 ◽

Vol 8 (5) ◽

pp. 499-503

Author(s):

Konstantina Kocheva ◽

Peter Petrov ◽

Georgi Georgiev

Keyword(s):

Hydrogen Peroxide ◽

Lipid Peroxidation ◽

Osmotic Stress ◽

Water Content ◽

Relative Water Content ◽

Water Status ◽

Free Proline ◽

Leaf Water Status ◽

Wheat Seedlings ◽

Relative Water

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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