Effect of Photoperiod and Temperature on Flowering in Pea (Pisum sativum L.)

1979 ◽  
Vol 6 (6) ◽  
pp. 573 ◽  
Author(s):  
GJ Berry ◽  
Y Aitken
Keyword(s):  
Growing Season ◽  
Effect Of Temperature ◽  
Photoperiod Response ◽  
Floral Initiation ◽  
Temperature Dependent ◽  
Flowering Genes ◽  
Pisum Sativum L ◽  
Temperature Interaction ◽  
Photoperiod Sensitive ◽  
The Relationship

Six pea varieties, early to late flowering, were grown in 16 environments made up of all combinations of four mean daily temperatures (6, 12, 18 or 24°C) and four photoperiods (8, 12, 16 or 24 h). For the earliest variety, days from sowing to first flower was inversely proportional to temperature, and independent of photoperiod. Sensitivity to photoperiod in the other five varieties was temperature-dependent. At 24°C, all were photoperiod-sensitive, but at 6°C only the latest three varieties were sensitive. Flowering was most rapid at 24°C in 24-h photoperiod. However, the lowest node of first flower occurred in 24 h photoperiod, irrespective of temperature. The duration of the period from floral initiation to first flower was independent of variety and photoperiod. Thus, any differences in flowering between varieties arose prior to floral initiation. These differences are explained by three factors: different times to floral initiation in 24 h photoperiod, a photoperiod response in low temperature, and a photoperiod-temperature interaction. These factors are related to the flowering genes Lf, Sn and Hr and the 'units of maturity genotype'. The likely genotypes of the varieties are deduced from the reported action of these genes. Vernalization is interpreted in terms of high-temperature inhibition of flowering in short photoperiods. The effect of temperature on the relationship between node of first flower and days from sowing to floral initiation, and the influence of genotype and growing season on flowering time, are also discussed.

Skeletal muscle fatigue in vitro is temperature dependent

1986 ◽  
Vol 61 (2) ◽  
pp. 660-665 ◽  
Author(s):  
S. S. Segal ◽  
J. A. Faulkner ◽  
T. P. White
Keyword(s):  
Effect Of Temperature ◽  
Isometric Contractions ◽  
Temperature Dependent ◽  
Temperature Optimum ◽  
Constant Frequency ◽  
Protocol Development ◽  
Effects Of Temperature ◽  
The Relationship ◽  
Bell Shaped Curve

Our purpose was to determine the effect of temperature on the fatigability of isolated soleus and extensor digitorum longus (EDL) muscles from rats during repeated isometric contractions. Muscles (70–90 mg) were studied at 20–40 degrees C in vitro. Fatigability was defined with respect to both the time and number of stimuli required to reach 50% of the force (P) developed at the onset of the fatigue test. Fatigue was studied during stimulation protocols of variable [force approximately 70% of maximum force (Po)] and constant frequency (28 Hz). Results for soleus and EDL muscles were qualitatively similar, but fatigue times were longer for soleus than for EDL muscles. During the variable-frequency protocol, development of approximately 70% of Po required an increase in stimulation frequency as temperature increased. During stimulation at these frequencies, fatigue time shortened as temperature increased. For both fatigue protocols, the relationship between temperature and the number of stimuli required to reach fatigue followed a bell-shaped curve, with maximum values at 25–30 degrees C. The temperature optimum for maximizing the number of isometric contractions to reach fatigue reflects direct effects of temperature on muscle function.

Effect of Temperature, Season, and Fish Size on Acute Lethality of Suspended Sediments to Coho Salmon (Oncorhynchus kisutch)

1991 ◽  
Vol 48 (3) ◽  
pp. 493-497 ◽  
Author(s):  
James A. Servizi ◽  
Dennis W. Martens
Keyword(s):  
Oxygen Transfer ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Suspended Sediments ◽  
Effect Of Temperature ◽  
Fraser River ◽  
Metabolic Rates ◽  
Temperature Dependent ◽  
Cough Reflex ◽  
The Relationship

Tolerance of underyearling coho salmon (Oncorhynchus kisutch) to Fraser River suspended sediments (SS) at 7 °C was independent of season of the year. However, coho of 0.52 g (4.0 cm) possessed only 35% of the tolerance of larger specimens. Tolerance to SS was temperature dependent, with 96-h LC50 at 1 and 18 °C being 47 and 33%, respectively, of the value at 7 °C. Tolerance was further reduced among underyearling coho which were later found to have a viral kidney infection. Cough reflex, oxygen transfer, oxygen saturation levels, metabolic rates, and capacity to do work all probably affect the relationship between SS tolerance and temperature.

scholarly journals EFFECT OF PHOTOPERIOD AND TEMPERATURE ON SEEDLING DEVELOPMENT OF OLLI AND VANTAGE BARLEY

1969 ◽  
Vol 49 (2) ◽  
pp. 139-147 ◽  
Author(s):  
D. G. Faris ◽  
Lila Krahn ◽  
A. A. Guitard
Keyword(s):  
Ground Level ◽  
Barley Plant ◽  
Floral Initiation ◽  
Hordeum Vulgare L ◽  
Vegetative Development ◽  
Vegetative Period ◽  
Floral Organogenesis ◽  
First Arrival ◽  
Photoperiod Sensitive ◽  
The Relationship

A photoperiod-sensitive cultivar (Vantage) and a non-sensitive cultivar (Olli) of barley (Hordeum vulgare L.) were grown under photoperiods of 8, 16, and 24 hr at 13 and 24 °C to study the relationship between apical and vegetative development of the seedling. The high temperature tended to accentuate the effect of short days in extending the vegetative period before floral initiation, but caused a shortening of the period between the formation of double ridges and the first arrival of a node at ground level (NGL). At 13 °C NGL coincided with the formation of stamen initials, but at 24 °C NGL occurred at progressively earlier stages of floral organogenesis as daylengths were shortened to 16 and 8 hr. The results suggest that almost invariably NGL can be used to indicate that floral initiation has occurred in a barley plant, but cannot be used to indicate stage of floral organogenesis under all conditions.

scholarly journals Effect of temperature on the developmental rate, longevity and parasitism of Aphidius ervi Haliday (Hymenoptera: Aphidiidae)

2008 ◽  
Vol 44 (No. 1) ◽  
pp. 19-24 ◽  
Author(s):  
R. Malina ◽  
J. Praslička
Keyword(s):  
Adult Development ◽  
Developmental Rate ◽  
Aphidius Ervi ◽  
Effect Of Temperature ◽  
Degree Days ◽  
Temperature Dependent ◽  
Dependent Development ◽  
Aphis Pomi ◽  
Reported Data ◽  
The Relationship

Temperature-dependent development, longevity and parasitism of the parasitoid Aphidius ervi Haliday was measured at four constant temperatures between 15°C and 30°C using Aphis pomi de Geer as host. The thresholds for egg-mummy and mummy-adult development were 6.8°C and 3.9°C, respectively. Development into mummies required an average of 146.3 degree-days (DD), while development into adults took an average of 85.3 DD. Longevity was increasing linearly in the range from 15°C to 25°C (8–15 days), but was lower at 30°C (11 days). The relationship between parasitism, recorded as percent aphids mummified, and temperature was increasing at the temperatures 15–25°C, but decreasing at higher temperatures; 10.8% of the aphids were parasitised at 15°C, 15.9% at 25°C and 14.6% at 30°C. These results are compared with previously reported data on temperature-dependent development of A. ervi on a different host.

Barley seed storage under controlled conditions

2019 ◽  
pp. 140-150 ◽  
Author(s):  
O. A. Zadorozhna ◽  
T. P. Shyianova ◽  
M.Yu. Skorokhodov
Keyword(s):  
Hordeum Vulgare ◽  
Moisture Content ◽  
Spring Barley ◽  
Seed Storage ◽  
Growing Season ◽  
Storage Conditions ◽  
Meteorological Conditions ◽  
Hordeum Vulgare L ◽  
The Relationship ◽  
And Storage

Seed longevity of 76 spring barley gene pool samples (Hordeum vulgare L. subsp. distichon, convar. distichon: 56 nutans Schubl., two deficience (Steud.) Koern., two erectum Rode ex Shuebl., two medicum Koern.; convar. nudum (L.) A.Trof.: one nudum L. та subsp. vulgare: convar. vulgare: nine pallidum Ser., three rikotense Regel.; convar. coeleste (L.) A.Trof.: one coeleste (L.) A.Trof.) from 26 countries, 11 years and four places of reproduction was analyzed. Seeds with 5–8% moisture content were stored in chamber with unregulated and 4oC temperature. The possibility of seed storage under these conditions for at least 10 years without significant changes in germination has been established. The importance of meteorological conditions in the formation and ripening of seeds for their longevity is confirmed. The relationship between the decrease of barley seeds longevity and storage conditions, amount of rainfall, temperature regime during the growing season of plants is discussed.

scholarly journals The Respiration of some Planktonic copepods II. The Effect Of Temperature

1953 ◽  
Vol 31 (3) ◽  
pp. 447-460 ◽  
Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont
Keyword(s):  
Respiratory Rate ◽  
The Body ◽  
The Other ◽  
Effect Of Temperature ◽  
Acartia Clausi ◽  
Temora Longicornis ◽  
Different Temperatures ◽  
Planktonic Copepods ◽  
The Difference ◽  
The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

scholarly journals The modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Rui Zhang ◽  
Yujie Meng ◽  
Hejia Song ◽  
Ran Niu ◽  
Yu Wang ◽  
...  
Keyword(s):  
Air Pollution ◽  
High Temperature ◽  
Air Pollutants ◽  
Meteorological Data ◽  
Effect Of Temperature ◽  
Distributed Lag ◽  
Modification Effect ◽  
Incidence Risk ◽  
The Impact ◽  
The Relationship

Abstract Background Although exposure to air pollution has been linked to many health issues, few studies have quantified the modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China. Methods The data of daily incidence of influenza and the relevant meteorological data and air pollution data in Ningbo from 2014 to 2017 were retrieved. Low, medium and high temperature layers were stratified by the daily mean temperature with 25th and 75th percentiles. The potential modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo was investigated through analyzing the effects of air pollutants stratified by temperature stratum using distributed lag non-linear model (DLNM). Stratified analysis by sex and age were also conducted. Results Overall, a 10 μg/m3 increment of O3, PM2.5, PM10 and NO2 could increase the incidence risk of influenza with the cumulative relative risk of 1.028 (95% CI 1.007, 1.050), 1.061 (95% CI 1.004, 1.122), 1.043 (95% CI 1.003, 1.085), and 1.118 (95% CI 1.028, 1.216), respectively. Male and aged 7–17 years were more sensitive to air pollutants. Through the temperature stratification analysis, we found that temperature could modify the impacts of air pollution on daily incidence of influenza with high temperature exacerbating the impact of air pollutants. At high temperature layer, male and the groups aged 0–6 years and 18–64 years were more sensitive to air pollution. Conclusion Temperature modified the relationship between air pollution and daily incidence of influenza and high temperature would exacerbate the effects of air pollutants in Ningbo.

The effect of temperature-dependent thermal parameters in thermal models of subduction zones

2021 ◽  
Author(s):  
Iris van Zelst ◽  
Timothy J. Craig ◽  
Cedric Thieulot
Keyword(s):  
Subduction Zones ◽  
Thermal Parameters ◽  
Dislocation Creep ◽  
Seismogenic Zone ◽  
Effect Of Temperature ◽  
Temperature Dependent ◽  
Thermal Models ◽  
Intermediate Depth ◽  
Dehydration Reactions ◽  
Model Setup

<p>The thermal structure of subduction zones plays an important role in the seismicity that occurs there with e.g., the downdip limit of the seismogenic zone associated with particular isotherms (350 °C - 450 °C) and intermediate-depth seismicity linked to dehydration reactions that occur at specific temperatures and pressures. Therefore, accurate thermal models of subduction zones that include the complexities found in laboratory studies are necessary. One of the often-ignored effects in models is the temperature-dependence of the thermal parameters such as the thermal conductivity, heat capacity, and density.<span> </span></p><p>Here, we build upon the model setup presented by Van Keken et al., 2008 by including temperature-dependent thermal parameters to an otherwise clearly constrained, simple model setup of a subducting plate. We consider a fixed kinematic slab dipping at 45° and a stationary overriding plate with a dynamic mantle wedge. Such a simple setup allows us to isolate the effect of temperature-dependent thermal parameters. We add a more complex plate cooling model for the oceanic plate for consistency with the thermal parameters.<span> </span></p><p>We test the effect of temperature-dependent thermal parameters on models with different rheologies, such as an isoviscous wedge, diffusion and dislocation creep. We find that slab temperatures can change by up to 65 °C which affects the location of isotherm depths. The downdip limit of the seismogenic zone defined by e.g., the 350 °C isotherm shifts by approximately 4 km, thereby increasing the maximum possible rupture area of the seismogenic zone. Similarly, the 600 °C isotherm is shifted approximately 30 km deeper, affecting the depth at which dehydration reactions and hence intermediate-depth seismicity occurs. Our results therefore show that temperature-dependent thermal parameters in thermal models of subduction zones cannot be ignored when studying subduction-related seismicity.<span> </span></p>

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