Preforming floral primordia converge on a narrow range of stages at dormancy despite multiple effects of temperature on development

2021 ◽  
Author(s):  
Eileen P. Schaub ◽  
Christa P. H. Mulder ◽  
Pamela K. Diggle
Keyword(s):  
Narrow Range ◽  
Floral Primordia ◽  
Effects Of Temperature

scholarly journals Effects of floral thermogenesis on pollen function in Asian skunk cabbage Symplocarpus renifolius

2009 ◽  
Vol 5 (4) ◽  
pp. 568-570 ◽  
Author(s):  
Roger S. Seymour ◽  
Yuka Ito ◽  
Yoshihiko Onda ◽  
Kikukatsu Ito
Keyword(s):  
Growth Rate ◽  
Pollen Germination ◽  
Narrow Range ◽  
Temperature Tolerance ◽  
Early Spring ◽  
Long Period ◽  
Pollen Tube Growth Rate ◽  
Skunk Cabbage ◽  
Effects Of Temperature

The effects of temperature on pollen germination and pollen tube growth rate were measured in vitro in thermogenic skunk cabbage, Symplocarpus renifolius Schott ex Tzvelev, and related to floral temperatures in the field. This species has physiologically thermoregulatory spadices that maintain temperatures near 23°C, even in sub-freezing air. Tests at 8, 13, 18, 23, 28 and 33°C showed sharp optima at 23°C for both variables, and practically no development at 8°C. Thermogenesis is therefore a requirement for fertilization in early spring. The narrow temperature tolerance is probably related to a long period of evolution in flowers that thermoregulate within a narrow range.

Some Effects of Temperature and Light on Floral Initiation and Development in Acacia pycnantha

1985 ◽  
Vol 12 (2) ◽  
pp. 109 ◽  
Author(s):  
M Sedgley
Keyword(s):  
Light Intensity ◽  
Floral Development ◽  
Early Stage ◽  
The Other ◽  
Floral Initiation ◽  
Ambient Conditions ◽  
Low Light ◽  
Floral Primordia ◽  
Effects Of Temperature ◽  
Normal Light

Floral initiation and development in Acacia pycnantha were studied under three environments. Two had ambient southern Australian temperatures of warm summer (mean max. 32°C, mean min. 16°C) and cool winter (mean max. 19°C, mean min. 8°C), one with full sunlight (outside) and the other with 30% light intensity (shadehouse). The other environment (glasshouse) had slightly lower than normal light intensity and a relatively constant year round temperature of mean 28°C maximum and 16°C minimum. Plants were scored for microscopic and macroscopic evidence of floral initiation and development. Floral primordia were initiated all year round under all environments. Floral development proceeded normally under ambient conditions of temperature and light, and anthesis occurred between August and October. Under low light intensity, floral development did not progress beyond a very early stage and macroscopically visible racemes were rare. Under the constant temperatures, floral development proceeded normally up to the stage of microsporogenesis and megasporogenesis. Meiosis did not occur and inflorescence buds ceased growth and were shed from the plant. Plants were transferred between the outside and glasshouse conditions in June, at around the stage of meiosis. Those transferred from outside to the glasshouse did not flower whereas some of those transferred from the glasshouse to outside flowered, but later and for a shorter period than plants maintained outside throughout. It appears that a 70% reduction in sunlight inhibits floral development at an early stage and that temperatures of approximately mean maximum 19°C and minimum 8°C are required for meiosis in Acacia pycnantha.

Weather, Physiology and Seasonality of Tea (Camellia sinensis) Yields in Malawi

1979 ◽  
Vol 15 (4) ◽  
pp. 321-330 ◽  
Author(s):  
G. R. Squire
Keyword(s):  
Water Potential ◽  
Air Temperature ◽  
Shoot Growth ◽  
Narrow Range ◽  
Field Measurements ◽  
Base Temperature ◽  
Saturation Deficit ◽  
Mean Temperature ◽  
Effects Of Temperature ◽  
Independent Effects

SUMMARYField measurements with a pressure chamber showed that the water potential of tea shoots was more closely related to the atmospheric saturation deficit than to the amount of water in the soil. Records for shoot growth and weather then revealed that, within a narrow range of mean temperature, the weekly rate of shoot extension was inversely related to mean saturation deficit measured at 1400 h. During periods when saturation deficit did not rise above 20 mbar, the rate of shoot extension varied linearly with mean temperature above a base temperature of 12.5–13.0°C. These correlations suggested that seasonality of shoot growth in tea can be explained largely by the independent effects of temperature and humidity. The effect of mean air temperature on the rate of shoot extension was confirmed in a glasshouse built over an established crop.

scholarly journals Effects of temperature and salinity on the survival rates of coxicerberus ramosae (Albuquerque, 1978), an interstitial isopod of a Sandy Beach on the coast of Brazil

2009 ◽  
Vol 52 (5) ◽  
pp. 1179-1187 ◽  
Author(s):  
Elaine Figueiredo Albuquerque ◽  
Bruno Meurer ◽  
Godofredo da Camara Genofre Netto
Keyword(s):  
Intertidal Zone ◽  
Rio De Janeiro ◽  
Sandy Beach ◽  
Narrow Range ◽  
Survival Rates ◽  
Sandy Beaches ◽  
Statistical Analyses ◽  
High Survival ◽  
Combined Effects ◽  
Effects Of Temperature

The tolerance to the combined effects of temperature and salinity was investigated in the interstitial isopod Coxicerberus ramosae (Albuquerque, 1978), a species of intertidal zone of sandy beaches in Rio de Janeiro, Brazil. The animals were collected on Praia Vermelha Beach. The experiments lasted 24 h and nine salinities and seven temperatures were used for a total of 63 combinations. Thirty animals were tested in each combination. The species showed high survival in most of the combinations. The temperature of 35 ºC was lethal and at 5 ºC, the animals tolerated only a narrow range of salinities. The statistical analyses showed that the effects of temperature and salinity were significant on the survival, which confirmed the euryhalinity and eurythermy of this species.

Effects of temperature acclimation on crayfish hemocyanin oxygen binding

1981 ◽  
Vol 240 (1) ◽  
pp. R93-R98 ◽  
Author(s):  
P. S. Rutledge
Keyword(s):  
Narrow Range ◽  
Oxygen Affinity ◽  
Temperature Acclimation ◽  
Structural Basis ◽  
Acclimation Temperature ◽  
Oxygen Binding ◽  
Functional Changes ◽  
Acclimation Response ◽  
Effects Of Temperature ◽  
Range Of Values

Crayfish, Pacifastacus leniusculus, were acclimated to 10, 20, and 25 degrees C for 1 mo. Hemocyanin from animals at these three acclimation temperatures showed distinctly different oxygen binding patterns. At any particular set of test temperature and pH, hemocyanin from 10 degrees C-acclimated animals had the lowest oxygen affinity and the greatest cooperativity, whereas hemocyanin from 25 degrees C-acclimated animals had the highest oxygen affinity and the lowest cooperativity. When tested at their own acclimation temperature, and at normal hemolymph pH for that temperature, all three hemocyanins showed oxygen pressure for half-saturation of hemoglobin of 6-7 Torr. Thus acclimation keeps oxygen affinity centered around a narrow range of values. The acclimation response probably eliminates hemocyanin oxygen affinity as a major factor in the decline of oxygen uptake ability in the crayfish above 20 degrees C. The structural basis for the observed functional changes in the hemocyanin is not yet clear.

(111) Monocrystalline Nickel Films

1972 ◽  
Vol 30 ◽  
pp. 512-513
Author(s):  
T.E. Pratt ◽  
R.W. Vook
Keyword(s):  
Film Thickness ◽  
Deposition Rate ◽  
Room Temperature ◽  
Narrow Range ◽  
High Vacuum ◽  
Residual Pressure ◽  
Temperature Dependent ◽  
Deposition Parameters ◽  
Transmission Electron ◽  
Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

State-by-State Use of AMA Guides

2019 ◽  
Vol 24 (5) ◽  
pp. 3-7, 16
Keyword(s):  
Expert Testimony ◽  
Narrow Range ◽  
The United States ◽  
Workers Compensation ◽  
Federal Employees ◽  
Permanent Disability ◽  
Sixth Edition ◽  
History Of ◽  
Canadian Provinces

Abstract This article presents a history of the origins and development of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), from the publication of an article titled “A Guide to the Evaluation of Permanent Impairment of the Extremities and Back” (1958) until a compendium of thirteen guides was published in book form in 1971. The most recent, sixth edition, appeared in 2008. Over time, the AMA Guides has been widely used by US states for workers’ compensation and also by the Federal Employees Compensation Act, the Longshore and Harbor Workers’ Compensation Act, as well as by Canadian provinces and other jurisdictions around the world. In the United States, almost twenty states have developed some form of their own impairment rating system, but some have a narrow range and scope and advise evaluators to consult the AMA Guides for a final determination of permanent disability. An evaluator's impairment evaluation report should clearly document the rater's review of prior medical and treatment records, clinical evaluation, analysis of the findings, and a discussion of how the final impairment rating was calculated. The resulting report is the rating physician's expert testimony to help adjudicate the claim. A table shows the edition of the AMA Guides used in each state and the enabling statute/code, with comments.

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