INDUCTION OF SPROUTING IN DORMANT YAM (DIOSCOREA SPP.) TUBERS WITH INHIBITORS OF GIBBERELLINS

2003 ◽  
Vol 39 (2) ◽  
pp. 209-217 ◽  
Author(s):  
H. SHIWACHI ◽  
T. AYANKANMI ◽  
R. ASIEDU ◽  
M. ONJO
Keyword(s):  
Ambient Temperature ◽  
Constant Temperature ◽  
Planting Date ◽  
Dormant Seed ◽  
Treatment Timing ◽  
Seed Tubers ◽  
Breeding Programmes ◽  
Prohexadione Calcium

A reliable means to induce sprouting in dormant seed tubers of yams (Dioscorea species) is required to enhance flexibility in planting date and rate of propagation of the crop. Experiments were conducted to assess the potential of two gibberellin inhibitors, Uniconazole-P and Prohexadione-calcium, to induce sprouting in tubers from three varieties of D. rotundata and four of D. alata. Uniconazole-P and Prohexadione-calcium shortened the period of dormancy in tubers of some varieties. In others, they either had no effect or extended dormancy. The varietal responses were also influenced by whether the tubers were treated at harvest (before shoot senescence) or four weeks after harvest by which time shoots had senesced fully. Tubers stored in darkness at a constant temperature of 30 °C sprouted earlier but lost weight faster than did those stored under natural daylight and ambient temperature. The apparent slow action of Uniconazole-P and Prohexadione-calcium, and their variable effectiveness in relation to variety, would limit their usefulness in seed or breeding programmes, or in determining treatment timing and the best storage environment for the tubers after treatment.

scholarly journals Analysing temperature protocol deviations in pome fruit export cold chains: A Western Cape case

2021 ◽  
Vol 15 ◽  
Author(s):  
Leila L. Goedhals-Gerber ◽  
Savia Fedeli ◽  
Frances E. Van Dyk
Keyword(s):  
South Africa ◽  
Supply Chain ◽  
The Netherlands ◽  
Ambient Temperature ◽  
Shelf Life ◽  
South African ◽  
Constant Temperature ◽  
Cold Chain ◽  
Western Cape ◽  
Pome Fruit

Background: A major concern plaguing South African pome fruit exporters is the volume of fruit going to waste during the export process. The senescence of fruits and the deterioration in its quality are accelerated by an increase in temperature. Thus, the first step in ultimately extending the shelf life of exported pome fruit and decreasing the risk of rejections is to ensure constant temperature control.Objectives: The study investigated the severity of temperature protocol deviations within the apple and pear export cold chains from the Western Cape, South Africa to the Netherlands. The study was undertaken in 2018 for Company X, an international fruit exporting firm, to improve the efficiency of its cold chains.Method: The research conducted temperature trials starting as close to the farm as possible and concluding as close to the end consumer as possible. Pulp and ambient temperature probes were inserted into and around the fruit to monitor export temperature profiles.Results: Firstly, the trial results show that non-compliance with temperature protocols occurred more often along the pome fruit export cold chain than initially anticipated. Secondly, the position within the pallet where the temperature breaks occurred highlighted an issue of heat retention resulting from unintentional oversights early in the cold chain. The study also identified areas of possible improvements where management could mitigate senescence factors.Conclusion: The study concluded that the efficient and effective functioning of a cold chain depends on cumulative efforts by all the supply chain partners rather than on the efforts of a single partner.

Fundamentals of Heat Transmission through the External Walls of Buildings

1965 ◽  
Vol 7 (4) ◽  
pp. 357-366 ◽  
Author(s):  
A. W. Pratt
Keyword(s):  
Heat Flux ◽  
Ambient Temperature ◽  
Constant Temperature ◽  
Thermal Capacity ◽  
Open Cavity ◽  
The Other ◽  
Heat Transmission ◽  
Theoretical Examination ◽  
Air Space

A theoretical examination is made of heat transmission through a wall exposed on one side to the weather and on the other facing an enclosure at a uniform and constant temperature. It is shown how the heat flux may be calculated exactly to take account of orientation, different degrees of exposure, and of air space ventilation in open cavity structures. The thermal capacity of the wall is considered by calculating solutions for transient and steady periodic variations in the ambient temperature at the weather surface.

scholarly journals Effect of Change in Ambient Temperature on Creep of Concrete

2021 ◽  
Vol 2 (1) ◽  
pp. 17-22
Author(s):  
Zainab Kammouna
Keyword(s):  
High Temperature ◽  
Ambient Temperature ◽  
Constant Temperature ◽  
Effect Of Temperature ◽  
The Impact

This article reviews the studies on the effect of temperature on the creep of concrete. Indeed, the temperature is one of the most important factors, as its rise leads to an acceleration of creep of concrete and thus an increase in its value compared to concrete under normal temperature. However, creep increases significantly if concrete under load is exposed to a high temperature. Thus, the creep value becomes higher than that of concrete exposed to a constant temperature (of the same level). Unfortunately, some of the codes for predicting creep of concrete (for instance the Eurocode) do not take into account the effect of high temperature on the creep of concrete under load. To clarify the impact of heating concrete under load (on creep) and distinguish it from its effect where it is constant, this study was carried out.

Fall condition factor and temperature influence the incidence of metamorphosis in sea lampreys, Petromyzon marinus

1994 ◽  
Vol 72 (6) ◽  
pp. 1134-1140 ◽  
Author(s):  
John A. Holmes ◽  
John H. Youson
Keyword(s):  
Ambient Temperature ◽  
Constant Temperature ◽  
Temperature Regime ◽  
Condition Factor ◽  
Petromyzon Marinus ◽  
Population Differences ◽  
Temperature Influence ◽  
Temperature Regimes ◽  
Sea Lampreys ◽  
Effects Of Temperature

Larval sea lampreys of immediate premetamorphic size (at least 120 mm and 3.0 g) were subjected to ambient or constant 21 °C temperature regimes for 9 months to investigate the influence of temperature and a fall condition factor (CF) of 1.50 or greater on the incidence of metamorphosis the following summer. The incidence of metamorphosis was 53% in the ambient temperature regime (29/55) and only 2% (1/55) in the constant temperature regime. About 64% (7/11) of the presumptively metamorphic larvae in the ambient temperature regime entered metamorphosis compared with 10% (1/10) in the constant temperature regime. Our predictions of metamorphosis based on CF were consistent with the observation that seven presumptively metamorphic larvae (CF ≥ 1.50) metamorphosed in the ambient temperature regime and that there was no metamorphosis among presumptively nonmetamorphic larvae in the constant temperature regime. Significantly more presumptively nonmetamorphic larvae in the ambient regime entered metamorphosis and fewer presumptively metamorphic larvae (CF < 1.50) metamorphosed in the constant temperature regime than expected. We attribute this response to the effects of temperature on metabolic processes. Larval sea lampreys of the appropriate size (≥ 120 mm and ≥ 3.0 g) with a CF of 1.50 or greater in the fall will usually enter metamorphosis the following July, but the accuracy of these predictions may be improved in some populations by using an empirically determined CF criterion that reflects seasonal or population differences in mass–length relationships.

Effect of mechanical and chemical seed treatments on the number and size of seed tubers and yield of potatoes

1984 ◽  
Vol 103 (3) ◽  
pp. 487-495 ◽  
Author(s):  
H. S. Sekhon ◽  
M. Singh
Keyword(s):  
Adverse Effect ◽  
Seed Size ◽  
Seed Yield ◽  
Field Experiments ◽  
Dormant Seed ◽  
Seed Rate ◽  
Seed Tubers ◽  
Thiourea Solution ◽  
Whole Seed ◽  
Cut Seed

SummaryField experiments to study the effect of pre-sprouting, cutting seed and seed soaking in plant regulators on the number and size of seed tubers and yield of potatoes were conducted during the autumn crop seasons of 1978–9 to 1980–1. At the same seed rate, cut seed produced significantly more sprouts and stems, seed-size tubers and seed yield than the whole seed without affecting the aggregate yield. Similar effects were recorded with soaking whole non-dormant tubers in 10 mg GA 3/1 solution for 15 min before planting. Soaking whole non-dormant seed in 0·5% thiourea solution for 1 h increased the number of sprouts and seed-size tubers, giving increases in seed yield of 2·26, 2·73 and 2·65 t/ha over soaking seed in water in the three consecutive years. The corresponding increases in aggregate yield were 1·79, 1·48 and 1·60 t/ha. Soaking cut seed in solutions of 10 mg GA 3/1 and 0·5% thiourea singly or in combination had an adverse effect on the yield of potatoes.

scholarly journals Temperature fluctuation improves oil palm (Elaeis guineensis) dura × pisifera seed germination

2020 ◽  
Vol 48 (1) ◽  
pp. 49-55 ◽  
Author(s):  
M.G. Norsazwan ◽  
U.R. Sinniah ◽  
A.B. Puteh ◽  
P. Namasivayam ◽  
M. Mohaimi ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Seed Germination ◽  
Ambient Temperature ◽  
Seed Production ◽  
Constant Temperature ◽  
Oil Palm ◽  
Temperature Fluctuation ◽  
Daily Maximum ◽  
Seed Processing ◽  
Temperature Amplitude

Oil palm is mainly propagated using dura × pisifera (D × P) hybrid seeds. Among the issues in D × P seed production are relatively poor seed germination and uniformity, despite heat treatment at 40°C to break dormancy. The conditions for germination post-heat-treatment may be a contributing factor. This study aimed to evaluate and compare the effect of constant 30°C or ambient temperature fluctuation at two different locations, Sime Darby Oil Palm Breeding Seed Processing Renggam, Johor and the Seed Production Unit (SPU) Banting, Selangor on oil palm D × P seed germination. At both locations, final mean germination percentage and speed were higher at fluctuating temperatures compared with constant 30°C. Under fluctuating conditions, the Oil Palm Breeding Seed Processing Renggam environment resulted in higher germination (85.8%) compared with SPU Banting (69.8%). Thus, the higher temperature amplitude (difference between daily maximum and minimum temperatures) was an important factor, resulting in higher germination. Therefore, oil palm can be germinated under ambient temperature conditions to obtain higher germination than under constant temperature, avoiding the need for maintaining expensive constant temperature germination rooms. In addition, a sufficiently high temperature amplitude can be beneficial in improving the ability to germinate and the speed of germination.

scholarly journals How Does Universal Gravitation Arise

2019 ◽  
pp. 21-30
Author(s):  
Huawang Li
Keyword(s):  
Ambient Temperature ◽  
Constant Temperature ◽  
Periodic Table ◽  
Gravitational Force ◽  
Elementary Particles ◽  
Universal Gravitation ◽  
Small Ball ◽  
Physical Experiments

Great principles are simple, and looking for the essence of physics requires us to trace the roots. Binary can be arranged to combine our information world, then would the three elementary particles [1] to form the periodic table of elements? Without giving them additional attributes (such as electricity, magnetism, gravity, etc.), would they further arranged this world? This paper proved the existence of a new particle through three physical experiments. The mass of this new particle is only 10-20 of the electron, and it is named Yizi. Through the discovery of Yizi, we will reveal the cause of gravitation and expound the essence of force. Experiment 1: The gravitational force between two objects is not only related to their masses but also their ambient temperature. The force between two objects is mutually exclusive when their temperature is lower than ambient. Experiment 2: Change the temperature of the big metal ball on the gravitation torsion scale, keeping the temperature of the small metal ball unchanged, and observe the force of the big ball on the small ball. Experiment 3: Under constant temperature and vacuum conditions, the temperature of an object is related to its mass. The greater its mass the higher its temperature.

SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

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