Changes in osmotic potential of Douglas-fir (Pseudotsugamenziesii) seedlings in relation to temperature and photoperiod

1989 ◽  
Vol 19 (4) ◽  
pp. 413-421 ◽  
Author(s):  
R. van den Driessche
Keyword(s):  
Osmotic Potential ◽  
Moisture Stress ◽  
Douglas Fir ◽  
Ambient Conditions ◽  
Xylem Water Potential ◽  
Volume Curve ◽  
Pressure Volume Curve ◽  
Curve Method ◽  
Volume Method ◽  
Lower Irradiance

The influences of temperature and photoperiod on osmotic potential (ψπ) at full turgor (ψπSAT) of container-grown Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings, which had completed one growing season, were examined in four experiments. Osmotic potential was measured cryoscopically on expressed sap and also by the pressure volume curve method in experiment 4. In experiment 1, started in January when ψπSAT was low, seedlings exposed to 25 °C for 5 weeks showed an increase in ψπSAT of 0.48 MPa compared with seedlings held at 8 °C, which showed little increase. There were no differences in ψπSAT between 8- and 16-h photoperiods. In experiment 2, started in September when ψπSAT was relatively high, seedlings of interior origin showed decreases in ψπSAT at 8 °C under an 8-h photoperiod (0.55 MPa) and at 25 °C under a 16-h photoperiod (0.69 MPa). Relatively little decrease in ψπSAT occurred in interior seedlings at 8 °C under a 16-h photoperiod. Coastal seedlings showed no decrease in ψπSAT in this experiment. In experiment 3, seedlings were exposed to 1 and 8 °C under an 8-h photoperiod, but at lower irradiance levels (85 μE•m−2•s−1) than those used in the other experiments (340 μE•m−2•s−1). Starting at values of about −1.9 MPa in October, ψπSAT decreased, on average, for coastal and interior seedlings by 0.76 MPa at 1 °C and 0.42 MPa at 8 °C over 6 weeks. Values for coastal seedlings decreased less (0.36 MPa) than those for interior seedlings (0.83 MPa). In experiment 4, seedlings were maintained under ambient conditions outdoors (mean temperatures of 5 °C day and 3 °C night), or at 12 or 25 °C under a 10-h photoperiod, in January and February. After 5 weeks of treatment, ψπSAT at 25 °C was 0.50 MPa, measured cryoscopically, or 0.80 MPa, measured by the pressure-volume method, higher than for seedlings under ambient conditions. At the turgor loss point (ψπSAT), ψπ was 1.36 MPa higher at 25 °C than at ambient temperature. The increase in ψπSAT at the beginning of the season and the reduction of ψπSAT at the end of the season were therefore dependent on temperature, but an interaction of photoperiod with temperature was observed in September. Index of injury values, calculated from leakage of electrolytes from drought-stressed needles and stems, showed a linear relationship to moisture stress between − 10 and − 2 MPa xylem water potential. In experiment 4, needle and stem index of injury values increased with increase in temperature, as did ψπSAT and ψπTLP values, tending to confirm that information about drought tolerance can be obtained by either method.

scholarly journals Mapping of Quantitative Trait Loci Controlling Adaptive Traits in Coastal Douglas Fir. III. Quantitative Trait Loci-by-Environment Interactions

Genetics ◽  
2003 ◽  
Vol 165 (3) ◽  
pp. 1489-1506
Author(s):  
Kathleen D Jermstad ◽  
Daniel L Bassoni ◽  
Keith S Jech ◽  
Gary A Ritchie ◽  
Nicholas C Wheeler ◽  
...  
Keyword(s):  
Quantitative Trait Loci ◽  
Quantitative Trait ◽  
Complex Traits ◽  
Moisture Stress ◽  
Interval Mapping ◽  
Douglas Fir ◽  
Adaptive Traits ◽  
Growth Cessation ◽  
Trait Loci ◽  
Growth Initiation

Abstract Quantitative trait loci (QTL) were mapped in the woody perennial Douglas fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) for complex traits controlling the timing of growth initiation and growth cessation. QTL were estimated under controlled environmental conditions to identify QTL interactions with photoperiod, moisture stress, winter chilling, and spring temperatures. A three-generation mapping population of 460 cloned progeny was used for genetic mapping and phenotypic evaluations. An all-marker interval mapping method was used for scanning the genome for the presence of QTL and single-factor ANOVA was used for estimating QTL-by-environment interactions. A modest number of QTL were detected per trait, with individual QTL explaining up to 9.5% of the phenotypic variation. Two QTL-by-treatment interactions were found for growth initiation, whereas several QTL-by-treatment interactions were detected among growth cessation traits. This is the first report of QTL interactions with specific environmental signals in forest trees and will assist in the identification of candidate genes controlling these important adaptive traits in perennial plants.

Derivation of recruitment function from the pressure–volume curve in an acute lung injury model

2015 ◽  
Vol 205 ◽  
pp. 16-20 ◽  
Author(s):  
Yoshihiro Uzawa ◽  
Mikiya Otsuji ◽  
Koichi Nakazawa ◽  
Wei Fan ◽  
Yoshitsugu Yamada
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Volume Curve ◽  
Pressure Volume Curve ◽  
Injury Model ◽  
Lung Injury Model

Elastic constants of inflated lobes of dog lungs

1976 ◽  
Vol 40 (4) ◽  
pp. 508-513 ◽  
Author(s):  
S. J. Lai-Fook ◽  
T. A. Wilson ◽  
R. E. Hyatt ◽  
J. R. Rodarte
Keyword(s):  
Bulk Modulus ◽  
Young’S Modulus ◽  
Elastic Constants ◽  
Young's Modulus ◽  
Poisson Ratio ◽  
Inflation Pressure ◽  
Initial State ◽  
Volume Curve ◽  
Pressure Volume Curve ◽  
Indentation Tests

The elastic constants of dog lungs were determined at various degrees of inflation. In one set of experiments, the lobes were subjected to deformations that approximated the conditions of uniaxial loading. These data, together with the bulk modulus data obtained from the local slope of the pressure-volume curve, were used to determine the two elastic moduli that are needed to describe small nonuniform deformations about an initial state of uniform inflation. The bulk modulus was approximately 4 times the inflation pressure, and Young's modulus was approximately 1.5 times the inflation pressure. In a second set of experiments, lobes were subjected to indentation tests using cylindric punches 1–3 cm in diameter. The value for Young's modulus obtained from these data was slightly higher, approximately twice the inflation pressure. These experiments indicate that the lung is much more easily deformable in shear than in dilatation and that the Poisson ratio for the lung is high, approximately 0.43.

Lung volumes and alveolar expansion pattern in immature rabbits treated with serum-diluted surfactant

2004 ◽  
Vol 97 (4) ◽  
pp. 1408-1413 ◽  
Author(s):  
Yongmei Xu ◽  
Tsutomu Kobayashi ◽  
Xiaoguang Cui ◽  
Keisuke Ohta ◽  
Chiharu Kabata ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Acute Respiratory Distress Syndrome ◽  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Distress Syndrome ◽  
Ringer Solution ◽  
Natural Surfactant ◽  
Volume Curve ◽  
Pressure Volume Curve ◽  
Expansion Pattern

In acute respiratory distress syndrome, mechanical ventilation often induces alveolar overdistension aggravating the primary insult. To examine the mechanism of overdistension, surfactant-deficient immature rabbits were anesthetized with pentobarbital sodium, and their lungs were treated with serum-diluted modified natural surfactant (porcine lung extract; 2 mg/ml, 10 ml/kg). By mechanical ventilation with a peak inspiration pressure of 22.5 cmH2O, the animals had a tidal volume of 14.7 ml/kg (mean), when 2.5 cmH2O positive end-expiratory pressure was added. This volume was similar to that in animals treated with nondiluted modified natural surfactant (24 mg/ml in Ringer solution, 10 ml/kg). However, the lungs fixed at 10 cmH2O on the deflation limbs of the pressure-volume curve had the largest alveolar/alveolar duct profiles (≥48,000 μm2), accounting for 38% of the terminal air spaces, and the smallest (<6,000 μm2), accounting for 31%. These values were higher than those in animals treated with nondiluted modified natural surfactant ( P < 0.05). We conclude that administration of serum-diluted surfactant to immature neonatal lungs leads to patchy overdistension of terminal air spaces, similar to the expansion pattern that may be seen after dilution of endogenous surfactant with proteinaceous edema fluid in acute respiratory distress syndrome.

Improved measurements of shear modulus and pleural membrane tension of the lung

1979 ◽  
Vol 47 (1) ◽  
pp. 175-181 ◽  
Author(s):  
M. A. Hajji ◽  
T. A. Wilson ◽  
S. J. Lai-Fook
Keyword(s):  
Shear Modulus ◽  
Transpulmonary Pressure ◽  
Elastic Half Space ◽  
Concentrated Force ◽  
Membrane Area ◽  
Volume Curve ◽  
Pressure Volume Curve ◽  
Pressure Independent ◽  
Work Done ◽  
The Continuum

The continuum solution for the deformation of an elastic half space covered by a membrane is used to interpret measurements of the indentation of lung lobes under a column of fluid. The shear modulus mu of the underlying parenchyma is found to be approximately 0.7 times transpulmonary pressure, independent of species size. The tension in the pleural membrane T increases rapidly with increasing membrane area. For dog lungs, the value of T is 10(3) to 10(4) dyn/cm. For the larger species tested, pigs and horses, T is larger. The continuum solution shows that a concentrated force applied to the pleural surface is distributed over a distance T/mu as it is transmitted across the pleural membrane. The membrane is important in determining the displacement produced by forces that act within a region that is small compared to this distance, approximately 2 cm for dog lungs. By comparing the tension-area curve of the pleural membrane with the pressure-volume curve of the lobe, it is found that the pleural membrane contributes about 20% of the work done by the lung during deflation.

Pressure-Volume Curve of the Remaining Lung after Lung Resection

1989 ◽  
Vol 21 (3-4) ◽  
pp. 168-174
Author(s):  
S. Hatakeyama ◽  
K. Harada ◽  
N. Saoyama ◽  
Y. Monden
Keyword(s):  
Lung Resection ◽  
Volume Curve ◽  
Pressure Volume Curve
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