WATER CONTENT IN PRIMARY GRAPE BUDS

Changes in water content of `Pinot Noir' endo- and ecodormant primary buds were gravimetrically partitioned into extracellular (ECW) and intracellular water (ICW). During endodormancy, water status remained unchanged with values of 0.6 and 0.1 mg/mg dw for ICW and ECW, respectively. Ecodormant buds, prior to budbreak, increased in ICW from 0.5 to 4.4 mg/mg dry weight for Jan. and Apr., respectively. Liquid water in the buds was determined by H-NMR. The spin-spin relaxation time (T2) at -30C represented the bound fraction, which peaked in Jan. at 0.3 mg/mg dw followed by a decrease to 0.2 mg/mg dw in March. During the dormant season the free fraction was always larger than the bound fraction. No vascular connection between bud and stem was observed by mid Jan. Changes in bound water indicated that there is a transient fraction changing to the free form. These changes were not strictly related to the bud's dormancy status.

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Adaptation to Water Stress of the Leaf Water Relations of Four Tropical Forage Species

Functional Plant Biology ◽

10.1071/pp9800207 ◽

1980 ◽

Vol 7 (2) ◽

pp. 207 ◽

Cited By ~ 49

Author(s):

JR Wilson ◽

MM Ludlow ◽

MJ Fisher ◽

E Schulze

Keyword(s):

Water Stress ◽

Water Content ◽

Water Relations ◽

Bound Water ◽

Leaf Tissue ◽

Dry Weight ◽

Panicum Maximum ◽

Soil Drying ◽

Buffel Grass ◽

Heteropogon Contortus

Three tropical grasses, green panic (Panicum maximum var, trichoglume), spear grass (Heteropogon contortus) and buffel grass (Cenchrus ciliaris) and the tropical legume siratro (Macroptilium atropurpureum), were grown in plots in a semi-arid field environment. The water relations characteristics of leaves from plants subjected to a soil drying cycle were compared with those of unstressed leaves from plants in irrigated plots. Minimum water potentials attained in the stressed leaves were c. -44, - 38, - 33 and - 13 bar for the four species, respectively. The grass leaves adjusted osmotically to water stress, apparently through accumulation of solutes, so that there was a decrease in osmotic potential at full turgor (Ψπ100) of 5.5, 3.9 and 7.1 bar, and in water potential at zero turgor (Ψ0) of 8.6, 6.5 and 8.6 bar for green panic, spear grass and buffel respectively. Water stress appeared to increase slightly the proportion of bound water (B) and the bulk modulus of elasticity (ε) of the grass leaves, but it did not alter the relative water content at zero turgor (RWC0) or the ratio of turgid water content to dry weight of the tissue. The Ψπ100 and Ψ0 of stressed siratro leaves decreased by 2.5-4 bar and 3-5 bar respectively when subjected to soil drying cycles. These changes could be explained by the marked decrease in the ratio of turgid water content to dry weight of the leaf tissue rather than by accumulation of solutes. The values of RWC0 and ε for siratro leaves were not altered by stress but, in contrast to the grasses, B was apparently decreased although the data exhibited high variability. Adjustments in Ψπ100 and Ψ0 of stressed leaves of buffel grass and siratro were largely lost within 10 days of rewatering.

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Effects of Ethanol on the NMR Characteristics of Rat Brain

The British Journal of Psychiatry ◽

10.1192/bjp.155.6.818 ◽

1989 ◽

Vol 155 (6) ◽

pp. 818-821 ◽

Cited By ~ 10

Author(s):

J. A. O. Besson ◽

S. G. Greentree ◽

M. A. Foster ◽

J. E. Rimmington

Keyword(s):

Water Content ◽

Bound Water ◽

Nmr Relaxation ◽

Chronic Administration ◽

Ethanol Exposure ◽

Acute Administration ◽

H Nmr ◽

Water State ◽

Transient Rise ◽

Membrane Changes

In rats, neither acute administration of ethanol nor the establishment of ethanol dependence by chronic administration for 28 days produced significant 1H-NMR relaxation changes. However, chronic ethanol intake for six months produced a transient rise in T1, with no change in T2 or water content. The significance of these results for study in man is discussed and a hypothesis is proposed to explain discrepant differences between T1, T2 and water content. It is suggested that T1 change with long-term ethanol exposure is related to altered free/bound water state secondary to cell membrane changes.

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USE OF 1H-NMR TO DETERMINE GRAPE BUD WATER STATUS DURING THE PHOTOPERIODIC INDUCTION OF DORMANCY

HortScience ◽

10.21273/hortsci.30.2.192f ◽

1995 ◽

Vol 30 (2) ◽

pp. 192f-193

Author(s):

Anne Fennell ◽

Carol Wake ◽

Paul Molitor

Keyword(s):

Water Content ◽

Water Status ◽

Relaxation Times ◽

Bulk Water ◽

Proton Nuclear Magnetic Resonance ◽

Tissue Water Content ◽

T2 Relaxation ◽

Tissue Water ◽

Woody Perennials ◽

H Nmr

Changes in tissue water content have been correlated, with varying success, with changes in freezing tolerance and dormancy in woody perennials. Recent studies indicate that changes in the state of water are more strongly correlated with dormancy than are changes in bulk water content. In this study, traditional destructive methods of monitoring tissue water content and dormancy were compared with measurements using nondestructive in situ proton nuclear magnetic resonance 1H NMR to determine plant water status. These studies were designed to determine whether changes in bud water status are correlated with dormancy and can be used as a reliable indicator of the onset of dormancy. Two-year-old Vitis riparia plants were subjected to short-day (SD, 8 h daylight) or long-day (LD, 15 h daylight), dormancy-inductive or noninductive treatments, respectively. Bud water was monitored at 2, 4, and 6 weeks of photoperiod treatments. SD treatments promoted a rapid onset in bud dormancy. Water content was not different in SD or LD treatments after 2 weeks. However, it did decrease over 6 weeks in both treatments, but SD treatments promoted a more rapid decrease in water content. The nondestructive 1H NMR methods give comparable measures of water content and provide a measure of bud water status. There were shorter T1 relaxation times in the 2-, 4-, and 6-week SD treatments. The SD treatment T2 relaxation times were shorter in the 4- and 6-week SD treatments only. Changes in the T1 and T2 relaxation times indicated changes in bud water status are correlated with the onset of dormancy.

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Characterization of frozen hydrated biological specimens by low-loss EELS

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132492 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1572-1573

Author(s):

Songquan Sun ◽

Richard D. Leapman

Keyword(s):

Water Content ◽

Direct Method ◽

Internal Standard ◽

Dry Weight ◽

Dark Field ◽

Protein Solutions ◽

Subcellular Compartment ◽

Differential Shrinkage ◽

Electron Energy Loss

Analyses of ultrathin cryosections are generally performed after freeze-drying because the presence of water renders the specimens highly susceptible to radiation damage. The water content of a subcellular compartment is an important quantity that must be known, for example, to convert the dry weight concentrations of ions to the physiologically more relevant molar concentrations. Water content can be determined indirectly from dark-field mass measurements provided that there is no differential shrinkage between compartments and that there exists a suitable internal standard. The potential advantage of a more direct method for measuring water has led us to explore the use of electron energy loss spectroscopy (EELS) for characterizing biological specimens in their frozen hydrated state.We have obtained preliminary EELS measurements from pure amorphous ice and from cryosectioned frozen protein solutions. The specimens were cryotransfered into a VG-HB501 field-emission STEM equipped with a 666 Gatan parallel-detection spectrometer and analyzed at approximately −160 C.

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STEM measurement of subcellular water distributions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148678 ◽

1993 ◽

Vol 51 ◽

pp. 568-569

Author(s):

R.D. Leapman ◽

S.Q. Sun ◽

S-L. Shi ◽

R.A. Buchanan ◽

S.B. Andrews

Keyword(s):

Water Content ◽

Internal Standard ◽

Dry Weight ◽

Dry Mass ◽

Scanning Transmission Electron Microscope ◽

Dark Field ◽

Bulk Water ◽

Inelastic Electron ◽

Scanning Transmission ◽

Annular Dark Field

Recent advances in rapid-freezing and cryosectioning techniques coupled with use of the quantitative signals available in the scanning transmission electron microscope (STEM) can provide us with new methods for determining the water distributions of subcellular compartments. The water content is an important physiological quantity that reflects how fluid and electrolytes are regulated in the cell; it is also required to convert dry weight concentrations of ions obtained from x-ray microanalysis into the more relevant molar ionic concentrations. Here we compare the information about water concentrations from both elastic (annular dark-field) and inelastic (electron energy loss) scattering measurements.In order to utilize the elastic signal it is first necessary to increase contrast by removing the water from the cryosection. After dehydration the tissue can be digitally imaged under low-dose conditions, in the same way that STEM mass mapping of macromolecules is performed. The resulting pixel intensities are then converted into dry mass fractions by using an internal standard, e.g., the mean intensity of the whole image may be taken as representative of the bulk water content of the tissue.

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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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Functional ecology of the biological soil crust in semiarid SE Spain: sun and shade populations of Diploschistes diacapsis (Ach.) Lumbsch.

The Lichenologist ◽

10.1017/s0024282905015021 ◽

2005 ◽

Vol 37 (5) ◽

pp. 425-432 ◽

Cited By ~ 38

Author(s):

Ana PINTADO ◽

Leopoldo G. SANCHO ◽

T. G. Allan GREEN ◽

José Manuel BLANQUER ◽

Roberto LÁZARO

Keyword(s):

Water Content ◽

Chlorophyll Content ◽

Unit Area ◽

Biological Soil Crust ◽

Dry Weight ◽

Mean Annual Precipitation ◽

Plant Colonization ◽

Soil Crust ◽

Active Time ◽

Exposed Population

The Tabernas badlands in semiarid south-east Spain is one of the driest regions in Europe with a mean annual precipitation of c. 240 mm. The landscape is deeply dissected, with canyons, ramblas and sparsely vegetated eroded badland slopes. The vegetation is predominantly a biological soil crust consisting of different types of lichen-rich communities, one of the more conspicuous being dominated by Diploschistes diacapsis (Ach.) Lumbsch. This lichen is mainly restricted to the north- facing slopes, where it forms extensive whitish carpets and probably plays an important role in preventing erosion of the slopes and allowing plant colonization. South-facing slopes are much more eroded and generally lack vegetation. %The photosynthetic performance of north (shade) and south-facing (sun) populations of D. diacapsis was studied to determine if these different populations showed any adaptations to the microclimatic conditions of their individual habitats. The response of CO2 exchange to light intensity, temperature and water content was measured under controlled conditions in the laboratory. Dry weight-based net photosynthetic rates were higher in the southern-exposed population but quantum efficiency, and light compensation points were similar. Thallus weight per unit area (LMA) was considerably higher for shade specimens but maximum water content and optimal water content were very similar and chlorophyll content on a dry weight basis was also similar. Chlorophyll content on an area basis was higher in the northern-exposed population and always much larger than those reported in other studies on the same species (up to 8 times larger) with the result that NP values on a chlorophyll basis were relatively low. The larger LMA meant that shade thalli stored more water per unit area which should ensure longer active periods than sun thalli. The results support a strategy pair of high NP and short active time versus low NP and long active time, both having been reported for other soil crust species. However, the visibly larger biomass of the shade D. diacapsis suggests that the lichen is at the limit of its adaptability in these habitats.

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Putative imbalanced amino acid metabolism in rainbow trout long term fed a plant-based diet as revealed by 1H-NMR metabolomics

Journal of Nutritional Science ◽

10.1017/jns.2021.3 ◽

2021 ◽

Vol 10 ◽

Author(s):

Catherine Deborde ◽

Blandine Madji Hounoum ◽

Annick Moing ◽

Mickaël Maucourt ◽

Daniel Jacob ◽

...

Keyword(s):

Amino Acids ◽

Rainbow Trout ◽

Amino Acid ◽

Amino Acid Content ◽

Proton Nuclear Magnetic Resonance ◽

Free Form ◽

Metabolomic Analysis ◽

Nmr Metabolomics ◽

H Nmr

Abstract The long-term effect of a plant (P)-based diet was assessed by proton nuclear magnetic resonance (1H-NMR) metabolomics in rainbow trout fed a marine fish meal (FM)–fish oil (FO) diet (M), a P-based diet and a control commercial-like diet (C) starting with the first feeding. Growth performances were not heavily altered by long-term feeding on the P-based diet. An 1H-NMR metabolomic analysis of the feed revealed significantly different soluble chemical compound profiles between the diets. A set of soluble chemical compounds was found to be specific either to the P-based diet or to the M diet. Pterin, a biomarker of plant feedstuffs, was identified both in the P-based diet and in the plasma of fish fed the P-based diet. 1H-NMR metabolomic analysis on fish plasma and liver and muscle tissues at 6 and 48 h post feeding revealed significantly different profiles between the P-based diet and the M diet, while the C diet showed intermediate results. A higher amino acid content was found in the plasma of fish fed the P-based diet compared with the M diet after 48 h, suggesting either a delayed delivery of the amino acids or a lower amino acid utilisation in the P-based diet. This was associated with an accumulation of essential amino acids and the depletion of glutamine in the muscle, together with an accumulation of choline in the liver. Combined with an anticipated absorption of methionine and lysine supplemented in free form, the present results suggest an imbalanced essential amino acid supply for protein metabolism in the muscle and for specific functions of the liver.

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Capability of leaf water content and its threshold values in reflection of soil–plant water status in maize during prolonged drought

Ecological Indicators ◽

10.1016/j.ecolind.2021.107395 ◽

2021 ◽

Vol 124 ◽

pp. 107395

Author(s):

Huailin Zhou ◽

Guangsheng Zhou ◽

Qijin He ◽

Li Zhou ◽

Yuhe Ji ◽

...

Keyword(s):

Water Content ◽

Water Status ◽

Leaf Water ◽

Plant Water Status ◽

Leaf Water Content ◽

Plant Water ◽

Threshold Values ◽

Prolonged Drought

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The Utilisation of metabolic Water in Insects

Bulletin of Entomological Research ◽

10.1017/s0007485300017351 ◽

1944 ◽

Vol 35 (2) ◽

pp. 127-139 ◽

Cited By ~ 60

Author(s):

G. Fraenkel ◽

M. Blewett

Keyword(s):

Body Weight ◽

Water Content ◽

Larval Development ◽

Dry Weight ◽

Larval Period ◽

Tribolium Confusum ◽

Ephestia Kuehniella ◽

Final Size ◽

Metabolic Water ◽

Food Consumed

(1) Three insects,Tribolium confusum, Ephestia kuehniellaandDermestes vulpinus, have been grown at several humidities and the following factors have been determined: length of larval period; water content of food and of the freshly formed pupae; wet and dry weight of pupae and wet and dry weight of food consumed during larval development. The “net utilisation” of the food has been calculated as the ratio of dry weight of food eaten per larva to dry weight of pupa.(2) At lower humidities more food is eaten to produce a given unit of body weight. The length of the larval period increases and the weight of the pupae decreases.(3) More food is eaten at low humidities, because part of the food is utilised as water. As a consequence of this, the larva grows more slowly and its final size is smaller. It is shown forDermestesat 30 per cent. andEphestiaat 1 per cent. R.H. that less than 32·9 and 7·6 per cent. of the water in the pupae can be derived from water ingested with the food.

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