Water relations parameters on single leaves obtained in a pressure bomb and some ecological interpretations

1975 ◽  
Vol 53 (13) ◽  
pp. 1342-1346 ◽  
Author(s):  
Y. N. S. Cheung ◽  
M. T. Tyree ◽  
J. Dainty
Keyword(s):  
Cell Wall ◽  
Water Potential ◽  
Osmotic Pressure ◽  
Water Loss ◽  
Ecological Significance ◽  
Cell Wall Elasticity ◽  
Use Of Data ◽  
Adaptive Value ◽  
Pressure Bomb ◽  
Volume Relation

The physical implications of the various parameters obtained from a pressure-bomb study are explored and related to their possible ecological significance. Our analysis suggests that the original bulk osmotic pressure, the bulk osmotic pressure at incipient plasmolysis, and cell wall elasticity are closely associated with the extent to which a leaf can osmoregulate or conserve water within a certain range of water potential change in the environment and might therefore have certain adaptive value. The pressure–volume relation could be applied to predict changes in leaf water potential at various degrees of water loss in the field. The values of these various parameters were obtained from a pressure-bomb study on single leaves from a wide variety of species. The use of data from single leaves as compared with whole shoots is discussed.

A comparison of systematic errors between the Richards and Hammel methods of measuring tissue – water relations parameters

1978 ◽  
Vol 56 (17) ◽  
pp. 2153-2161 ◽  
Author(s):  
M. T. Tyree ◽  
M. E. MacGregor ◽  
A. Petrov ◽  
M. I. Upenieks
Keyword(s):  
Cell Wall ◽  
Osmotic Pressure ◽  
Water Relations ◽  
Turgor Pressure ◽  
Systematic Errors ◽  
Tissue Water ◽  
Cell Wall Elasticity ◽  
Pressure Bomb ◽  
Bomb Method

The pressure bomb is being used to a much greater extent to measure some tissue – water relations parameters such as osmotic pressure, turgor pressure, and cell wall elasticity. Recently, Richards has developed a faster pressure-bomb method of obtaining these and other parameters than the method used by Hammel and modified by us. In this paper, we compare the two methods and conclude that Richards’ method should not be used when accuracy is deemed important. The Richards method usually overestimates osmotic pressure by 0.2 MPa (= 2 bars) and sometimes by 0.8 MPa (= 8 bars).

The water relations of hemlock (Tsuga canadensis). IV. The dependence of the balance pressure on temperature as measured by the pressure-bomb technique

1974 ◽  
Vol 52 (5) ◽  
pp. 973-978 ◽  
Author(s):  
M. T. Tyree ◽  
J. Dainty ◽  
D. M. Hunter
Keyword(s):  
Temperature Dependence ◽  
Water Potential ◽  
Osmotic Pressure ◽  
Water Relations ◽  
Turgor Pressure ◽  
Tsuga Canadensis ◽  
Constant Volume ◽  
Pressure Bomb

The temperature dependence of the balance pressure is reported for shoots of Tsuga canadensis at constant volume, i.e., when water is neither added to nor removed from the shoot. Since the balance pressure closely equals minus the water potential, the temperature dependence of the balance pressure should reflect the combined temperature dependence of the osmotic and turgor pressures. Both the osmotic and the turgor pressures decline with decreasing temperature; frequently the turgor pressure declines 2 to 3 times more rapidly than the osmotic pressure, causing the balance pressure to rise with decreasing temperature. Only when the turgor pressure is zero (only beyond incipient plasmolysis) does the temperature dependence of the balance pressure closely follow the temperature dependence of the osmotic pressure; this occurs when the balance pressure equals or exceeds 24 bars.

The epicuticle of millipedes belonging to the genera Cingalobolus and Aulacobolus with special reference to seasonal variations

1968 ◽  
Vol 23 (6) ◽  
pp. 845-851 ◽  
Author(s):  
G. Sundara Rajulu ◽  
G. Krishnan
Keyword(s):  
Water Resources ◽  
Special Reference ◽  
Water Loss ◽  
Seasonal Variations ◽  
Rainy Season ◽  
Summer Season ◽  
Ecological Significance ◽  
Lipid Layer ◽  
Adaptive Value

The diplopods Cingalobolus bugnioni and Aulacobolus excellens possess an epicuticle formed of lipoproteins. But unlike in insect cuticles, the epicuticle lacks an outer lipid layer. The epicuticle is found only in the animals collected in summer months. At the commencement of the rainy season the new cuticle that is formed following moulting is without an epicuticle. The periodical presence of the epicuticle is of ecological significance. A study of the transpiration rates using animals with and without an epicuticle showed that in the former evaporation of water through the cuticle was much less than in the latter. It is suggested that the presence of an epicuticle during summer season is of adaptive value in that the restricted permeability properties of the epicuticle enable the animals to conserve their water resources. In the rainy season when there is plentiful supply of water in the environment the animals are without an epicuticle as there is no necessity to restrict water loss. The periodical absence of the epicuticle has been discussed in the light of previous reports on the cuticular organization of millipedes.

Water Uptake and Embryonic Development in Eggs of Chorthippus Brunneus Thunberg (Saltatoria: Acrididae)

1969 ◽  
Vol 50 (2) ◽  
pp. 327-333
Author(s):  
F. MORIARTY
Keyword(s):  
Sodium Chloride ◽  
Embryonic Development ◽  
Water Absorption ◽  
Osmotic Pressure ◽  
Water Uptake ◽  
Water Loss ◽  
Chloride Solutions ◽  
Sodium Chloride Solutions ◽  
Close Relationship ◽  
Further Development

1. The pattern of water absorption by eggs of Chorthippus brunneus varies greatly between individuals. 2. The time at which water is absorbed does not have a close relationship with the stage of embryonic development. 3. Water absorption is not essential for prediapause development. 4. Eggs can only undergo blastokinesis and further development, after diapause is broken, if some water has been absorbed. 5. The rate of water loss or gain varies with the osmotic pressure of sodium chloride solutions. 6. Eggs which have started to absorb water appear to become desiccated more rapidly than eggs which have not.

Atomic force microscopy based analysis of cell-wall elasticity in macroalgae

2018 ◽  
pp. 335-347 ◽  
Author(s):  
Thomas Torode ◽  
Marina Linardic ◽  
J. Louis Kaplan ◽  
Siobhan A. Braybrook
Keyword(s):  
Atomic Force Microscopy ◽  
Cell Wall ◽  
Force Microscopy ◽  
Cell Wall Elasticity ◽  
Atomic Force

scholarly journals Growth and Physiological Traits Associated with Drought Survival and Post-drought Recovery in Perennial Turfgrass Species

2010 ◽  
Vol 135 (2) ◽  
pp. 125-133 ◽  
Author(s):  
Qi Chai ◽  
Fang Jin ◽  
Emily Merewitz ◽  
Bingru Huang
Keyword(s):  
Cell Wall ◽  
Drought Stress ◽  
Osmotic Adjustment ◽  
Perennial Grass ◽  
Kentucky Bluegrass ◽  
Physiological Traits ◽  
Grass Species ◽  
Cell Wall Elasticity ◽  
Drought Recovery ◽  
Drought Survival

The objective of this study was to determine physiological traits for drought survival and post-drought recovery upon re-watering in two C3 perennial grass species, kentucky bluegrass [KBG (Poa pratensis)] and perennial ryegrass [PRG (Lolium perenne)]. Plants were maintained well watered or exposed to drought stress by withholding irrigation and were then re-watered in a growth chamber. KBG had significantly higher grass quality and leaf photochemical efficiency, and lower electrolyte leakage than PRG during 20 days of drought. After 7 days of re-watering, drought-damaged leaves were rehydrated to the control level in KBG, but could not fully recover in PRG. KBG produced a greater number of new roots, while PRG had more rapid elongation of new roots after 16 days of re-watering. Superior drought tolerance in KBG was associated with osmotic adjustment, higher cell wall elasticity, and lower relative water content at zero turgor. Osmotic adjustment, cell wall elasticity, and cell membrane stability could play important roles in leaf desiccation tolerance and drought survival in perennial grass species. In addition, post-drought recovery of leaf hydration level and physiological activity could be associated with the accumulation of carbohydrates in leaves and rhizomes during drought stress and new root production after re-watering.

Cell wall elasticity and Water Index (R970 nm/R900 nm) in wheat under different nitrogen availabilities

1996 ◽  
Vol 17 (2) ◽  
pp. 373-382 ◽  
Author(s):  
J. PENUELAS ◽  
I. FILELLA ◽  
L. SERRANO ◽  
R. SAVÉ
Keyword(s):  
Cell Wall ◽  
Water Index ◽  
Cell Wall Elasticity

Root Growth, Water Uptake and Canopy Development in Eucalyptus viminalis Seedlings

1994 ◽  
Vol 21 (1) ◽  
pp. 69 ◽  
Author(s):  
JG Phillips ◽  
SJ Riha
Keyword(s):  
Root Growth ◽  
Water Potential ◽  
Soil Water ◽  
Water Loss ◽  
Soil Water Potential ◽  
Water Extraction ◽  
Soil Conditions ◽  
Lower Section ◽  
Canopy Development ◽  
Eucalyptus Viminalis

A split-root experiment was conducted using Eucalyptus viminalis seedlings which were exposed to three watering regimes in order to investigate root growth and soil water extraction under conditions of a drying soil profile. Seedlings were grown in columns in which the soil was divided horizontally with a soft wax plate. Watering treatments were composed of (1) both upper and lower sections of the column well watered (W/W), (2) only the lower section well watered (D/W), and (3) water withheld completely from both upper and lower sections (D/D). Daily measurements included soil water potential (Ψs), column water loss and leaf elongation. Increase in above- and below-ground biomass was deter- mined from initial and final harvests after 25 days of treatment. Whole-column water loss and leaf extension were depressed as Ψs in the upper section of D/W and D/D decreased to -0.4 MPa over the first 8-10 days. However, water loss did not decrease significantly in the lower section of treatment D/W relative to the lower section of treatment W/W during this period. This indicated that water extraction by roots remaining in wet soil was not severely inhibited by the decrease in transpiration associated with the soil conditions in the upper profile. Root distribution at the end of the experiment indicated significant growth in the lower section of treatment D/W. There was evidence that hydraulic lifting of water between column sections may have occurred, as periodic increases in soil water potential of the unwatered upper section of D/W were observed.

scholarly journals Effects of Water Loss of 'Fuyu' Persimmon Fruit on Molecular Weights of Mesocarp Cell Wall Polysaccharides and Fruit Softening

2004 ◽  
Vol 73 (5) ◽  
pp. 460-468 ◽  
Author(s):  
Yasuhisa Tsuchida ◽  
Naoki Sakurai ◽  
Kunihisa Morinaga ◽  
Yoshiko Koshita ◽  
Toshikazu Asakura
Keyword(s):  
Cell Wall ◽  
Water Loss ◽  
Fruit Softening ◽  
Cell Wall Polysaccharides ◽  
Molecular Weights ◽  
Persimmon Fruit
Sign in / Sign up

Export Citation Format

Share Document