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.

scholarly journals Effects of Temperature, Salinity, pH, and Light on Filtering and Grazing Rates of a Calanoid Copepod (Schmackeria dubia)

2008 ◽  
Vol 8 ◽  
pp. 1219-1227 ◽  
Author(s):  
Changling Li ◽  
Xiaoxia Luo ◽  
Xianghu Huang ◽  
Binhe Gu
Keyword(s):  
Light Intensity ◽  
Calanoid Copepod ◽  
Food Sources ◽  
Calanoid Copepods ◽  
Low Light ◽  
Marine Food Web ◽  
Larval Fishes ◽  
Trophic Links ◽  
Marine Food ◽  
Effects Of Temperature

Calanoid copepods are key components of the marine food web and the food sources of many larval fishes and planktivores, and grazers of phytoplankton. Understanding the ranges of major environmental variables suitable for their growth is essential to maintain the balance between trophic links and resources protection. In this study, the effects of temperature, salinity, pH, and light intensity on the filtering and grazing rates of a herbivorous copepod (Schmackeria dubia) were conducted in several control experiments. Our results indicated that experimental animals grazed normally at water temperatures between 15 and 35°C. The filtering and grazing rates increased by onefold at water temperatures from 15 to 25°C, with a peak at around 30°C.S. dubiafed normally at salinity ranging from 20 to 30 ppt, with significantly low filtering and grazing rates at salinity below 15 ppt and above 35 ppt. The filtering and grazing rates increased as pH increased, peaked at approximately 8.5, and then decreased substantially. Light intensity also displayed an important impact on the filtering and grazing rates. Filtering and grazing rates were high when light intensity was greater than 20 and less than 200 µmol m-2s-1. S. dubia nearly stopped feeding at low light intensity (less than 20 µmol m-2s-1).

EFFECTS OF TEMPERATURE AND LIGHT INTENSITY ON NOCTURNAL ACTIVITY PATTERNS OF THE NORTHERN JUNE BEETLE, PHYLLOPHAGA FUSCA, AND THE COMMON JUNE BEETLE, P. ANXIA (COLEOPTERA: SCARABAEIDAE)

1982 ◽  
Vol 114 (12) ◽  
pp. 1151-1157 ◽  
Author(s):  
J. C. Guppy
Keyword(s):  
Light Intensity ◽  
Soil Temperature ◽  
Activity Patterns ◽  
Degree Days ◽  
Low Light ◽  
Flight Season ◽  
The Common ◽  
Effects Of Temperature ◽  
High Soil Temperature ◽  
Oviposition Sites

AbstractIn western Quebec, first flight of overwintered adults of the northern June beetle, Phyllophaga fusca (Froelich), and the common June beetle, P. anxia (Le Conte), occurred in mid-May with the accumulation of about 156 degree-days above 5 °C beginning 1 April. When soil temperature was 10 °C or higher, flight started 12–45 min after sunset, apparently in response to an endogenous rhythm that was triggered by low light intensity within the range 1.0 to 96.9 lux; high soil temperature induced early flight. Early in the flight season, duration of flight was 10–46 min and was inversely related to time of flight initiation. In early June, the flight began in darkness and was associated with peak oviposition and ageing; it lasted 20–35 min and was directed into the trees or to oviposition sites within a field.Males were attracted to light during a pre-copulatory flight which lasted more than 1 h until maximum coupling occurred near 2230 h; beetles remained in copula for 3 h or more. Morning flight directly back to the soil was triggered by light intensity increasing to about 1.0 lux.

scholarly journals Environmental Control of Flowering in Pennsylvania Sedge

2014 ◽  
Vol 24 (3) ◽  
pp. 301-306
Author(s):  
Esther E. McGinnis ◽  
Alan G. Smith ◽  
Mary H. Meyer
Keyword(s):  
Floral Development ◽  
Environmental Control ◽  
Flowering Plants ◽  
The Other ◽  
Floral Initiation ◽  
Upland Forest ◽  
Native Habitat ◽  
Short Day ◽  
Carex Pensylvanica ◽  
Achene Production

Pennsylvania sedge (Carex pensylvanica) is an upland forest sedge with restoration and horticultural potential as a low-maintenance groundcover for dry shade. For large landscape and restoration plantings, seed or achenes in this case are much preferred due to lower labor and material costs. However, pennsylvania sedge typically produces few achenes in its native habitat. As a first step in improving achene production, this research evaluated the effect of vernalization and photoperiod on floral initiation and development. We conclude that this sedge is an obligate short-day plant that does not require vernalization for flowering. Plants flowered when exposed to daylengths of 6 to 12 hours. Flowering was completely inhibited with 14-hour photoperiods. Pennsylvania sedge was florally determined after 4 weeks of 8-hour photoperiods. Inflorescence quantity and normal floral development varied by clone and by weeks of exposure to 8-hour photoperiods. For two of the clones, the largest number of normal monoecious inflorescences was produced with 8 to 10 weeks of 8-hour photoperiods while the other two clones only required 6 to 8 weeks of exposure to inductive photoperiods. Therefore, it is important to evaluate observable variation between clones when attempting to propagate pennsylvania sedge.

scholarly journals Influence of light curing source on microhardness of composite resins of different shades

2006 ◽  
Vol 14 (1) ◽  
pp. 10-15 ◽  
Author(s):  
André Luiz Fraga Briso ◽  
Tânia Maria Fedel ◽  
Sibéria de Morais Pereira ◽  
Sílvio José Mauro ◽  
Renato Herman Sundfeld ◽  
...  
Keyword(s):  
Light Intensity ◽  
Confidence Level ◽  
Composite Resin ◽  
Composite Resins ◽  
The Other ◽  
Light Sources ◽  
Low Light ◽  
Tukey Test ◽  
Light Curing ◽  
Hardness Values

INTRODUCTION: The evolution of light curing units can be noticed by the different systems recently introduced. The technology of LED units promises longer lifetime, without heating and with production of specific light for activation of camphorquinone. However, further studies are still required to check the real curing effectiveness of these units. PURPOSE: This study evaluated the microhardness of 4 shades (B-0.5, B-1, B-2 and B-3) of composite resin Filtek Z-250 (3M ESPE) after light curing with 4 light sources, being one halogen (Ultralux - Dabi Atlante) and three LED (Ultraled - Dabi Atlante, Ultrablue - DMC and Elipar Freelight - 3M ESPE). METHODS: 192 specimens were distributed into 16 groups, and materials were inserted in a single increment in cylindrical templates measuring 4mm x 4mm and light cured as recommended by the manufacturer. Then, they were submitted to microhardness test on the top and bottom aspects of the cylinders. RESULTS: The hardness values achieved were submitted to analysis of variance and to Tukey test at 5% confidence level. It was observed that microhardness of specimens varied according to the shade of the material and light sources employed. The LED appliance emitting greater light intensity provided the highest hardness values with shade B-0.5, allowing the best curing. On the other hand, appliances with low light intensity were the least effective. It was also observed that the bottom of specimens was more sensitive to changes in shade. CONCLUSION: Light intensity of LED light curing units is fundamental for their good functioning, especially when applied in resins with darker shades.

scholarly journals Interaction of vernalization, photoperiod and light intensity in floral initiation of endive.

1959 ◽  
Vol 7 (1) ◽  
pp. 68-74
Author(s):  
J.F. Harrington ◽  
K. Verkerk ◽  
J. Doorenbos
Keyword(s):  
Low Temperature ◽  
Light Intensity ◽  
Vegetative Growth ◽  
Day Treatment ◽  
High Light Intensity ◽  
High Light ◽  
Floral Initiation ◽  
Low Light ◽  
Short Days ◽  
Limited Period

Vernalization of germinating endive seed or of young endive plants hastened floral initiation, but at the expense of vegetative growth. High temperatures after vernalization promoted bolting. Long days hastened bolting in both vernalized and non-vernalized plants, again at the expense of vegetative growth. A limited period of short days immediately after sowing also promoted flowering, and it is suggested that such short-day treatment may act as a partial substitute for low temperature. High light intensity had a supplementary effect in promoting bolting but, in contrast to vernalization and long days, caused more rapid vegetative growth than low light intensity.-Lab. TuinbPl., Wageningen. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Developmental morphology of the flower of Anaphyllopsis americana and its relevance to our understanding of basal Araceae

Botany ◽  
2008 ◽  
Vol 86 (12) ◽  
pp. 1467-1473 ◽  
Author(s):  
Denis Barabé ◽  
Christian Lacroix
Keyword(s):  
Phylogenetic Relationships ◽  
Floral Development ◽  
Early Stage ◽  
Anther Wall ◽  
Structural Constraints ◽  
Developmental Morphology ◽  
Circular Shape ◽  
Molecular Studies ◽  
Floral Primordia ◽  
Mode Of Development

The inflorescence of Anaphyllopsis americana (Engler) A. Hay consists of more than 100 flowers arranged in recognizable spirals. Each flower has four broad tepals enclosing four stamens that are not visible prior to anthesis. The unilocular ovary contains one ovule and bears a discoid stigma. The floral primordia are first initiated on the upper portion of the inflorescence. At an early stage during their development, the floral primordia have a circular shape. Two lateral tepals are initiated nearly simultaneously followed by two median tepals. After their initiation, each stamen is associated with a tepal of the same radius; the two lateral stamens are initiated first, directly opposite to the lateral tepals. The unilocular nature of the ovary is clearly visible during the early stages of development of the gynoecium. At dehiscence, anther wall raphides are present in anther locules and are mixed with pollen. The mode of floral development observed in Anaphyllopsis is similar to that reported for Anthurium jenmanii Engl. However, this similarity in mode of development may be linked to structural constraints rather than phylogenetic relationships. The presence of a few pentamerous flowers in the inflorescence of Anaphyllopsis suggests a possible relationship with Dracontium . This would be in accordance with recent molecular studies showing that Anaphyllopsis and Dracontium are closely related.

scholarly journals Floral sexual differentiation in Catasetum fimbriatum (Catasetinae, Orchidaceae) exposed to different light intensities

Lankesteriana ◽  
2016 ◽  
Vol 16 (1) ◽  
Author(s):  
Cristiano Pedroso-de-Moraes ◽  
Thiago De Souza-Leal ◽  
Alinne L. Saoncella ◽  
Marcílio De Almeida
Keyword(s):  
Light Intensity ◽  
Sexual Differentiation ◽  
Floral Development ◽  
High Light Intensity ◽  
Sexual Expression ◽  
Low Light ◽  
Environmental Stimulus ◽  
Sexual Determination ◽  
Definition Of ◽  
Catasetum Fimbriatum

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>To elucidate the factors which control the flower phenotypic plasticity of </span><span>Catasetum fimbriatum</span><span>, </span><span>studies focusing the floral development of the species were performed. The treatments were: high light intensity (1613 μmol.m</span><span>-2</span><span>.s</span><span>-1</span><span>); low light intensity (454 μmol.m</span><span>-2</span><span>.s</span><span>-1</span><span>) and mean light intensity (827 μmol.m</span><span>-2</span><span>.s</span><span>-1</span><span>). The floral </span><span>morphology and anatomy were analyzed to evaluate of the sequence of tissue development involved in the sexual differentiation. We found the presence of cell cluster with meristematic features in the ovaries and gynostemium </span><span>of the male and female diclinous flowers. These are responsible for the definition of the sexual expression of the </span><span>species, in the dependence of the environmental stimulus, related to the endogenous concentration of ethylene, allowing, consequently, the dedifferentiation and re-differentiation of those clusters in the sexual determination </span><span>of the flowers. There were no anatomical differences in floral tissues in different treatments. </span></p></div></div></div>

Cognitive Functioning and Other Discriminatory Variables in Anorexic Patients

2005 ◽  
Vol 27 (1) ◽  
pp. 191-210 ◽  
Author(s):  
Carmen García-Alba
Keyword(s):  
Cognitive Functioning ◽  
Research Study ◽  
Early Stage ◽  
Developmental Period ◽  
The Other ◽  
Model Synthesis ◽  
Consistent Function ◽  
Current Article ◽  
Rorschach Variables ◽  
Underlying Pathology

This study is part of a larger research study (doctoral dissertation), in which a comparative study with adolescent samples is done: 50 anorexic restricting patients (ANP), 50 patients diagnosed with depression (DP) and 50 non patients (NP). The proposed objective is two-fold: 1) To try to clarify the existing relationship between Anorexia (AN) and Depression (D), investigated from diverse disciplines but without conclusive results. 2) To detect in the ANP personality different traits from those of other groups, which should, if possible, allow to detect them at an early stage for an adequate prognosis. The current article presents the Rorschach findings in relation to the cognitive functioning of the ANP. In them, the following has been detected: (1) An information processing similar to that of the other groups, even with a more complete (L ≤ .99), more complex (DQ+↑) and better discriminated (Zd↑) grasp of the stimulus; (2) Mediating processes very similar to those of the other groups, sharing with them the perceptive maladjustments (X–%↑) and an excessive individualism (Xu%↑); (3) A clearly differentiating ideation disorder. Definitely, the ANP use predominantly ideation (M↑), but their thought, usually well-adjusted (MQo↑), presents eventual operations of delusional type (MQnone↑). Above that, their thinking is marked by a great passivity (Mp↑), which makes them more vulnerable to accept ideas without criticizing them and it results in a very inefficient thinking, which spins around these concepts without finding solutions, entering into a sort of ruminating which is completely unproductive. The differences toward the obsessive pathology are established. The discriminant analysis conducted with all the Rorschach variables that resulted as significant throughout the research, provides quite a consistent function which discriminates the ANP: MQnone↑, Mp↑, FD↓, Ma↑, MQo↑, AdjD↑, Sum H↑, (H)↑. Based on this we can understand that these adolescents, being in a developmental period of big changes and disorientations in relation with their own image, confronted with life events, and possibly starting off with some biologic vulnerability: (1) Due to the alterations of their ideation, accept without criticism (Mp) irrational ideas dominating in our culture, in which slimness appears as the only model, synthesis of intelligence, beauty and success; remaining captured in this type of mental activity (MQnone), which they cannot escape nor criticize (Mp), despite they reason adequately on other topics (MQo); (2) Their alterations of self-perception [(H)] make them hide themselves in a fantasized image, which is the axis of their interests and the only thing that really matters to them; (3) The resources they have to decide on behaviors and to finish these deliberately (AdjD), and their scarce tendency to the introspection (FD) lead to their decision of not eating, based on distorted and passively accepted thinking, which has great power and thus, so difficult to modify. Finally, based on the Rorschach data obtained, the hypothesis of a personality disorder as underlying pathology is pointed out.

The Application of UX Research in New Energy Vehicle Innovation

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Menghan TAO ◽  
Ning XIAO ◽  
Xingfu ZHAO ◽  
Wenbin LIU
Keyword(s):  
Early Stage ◽  
Rapid Expansion ◽  
The Other ◽  
Innovative Product ◽  
Stage Of Development ◽  
New Energy ◽  
New Energy Vehicle ◽  
The One ◽  
New Energy Vehicles ◽  
Degree Of Innovation

New energy vehicles(NEV) as a new thing for sustainable development, in China, on the one hand has faced the rapid expansion of the market; the other hand, for the new NEV users, the current NEVs cannot keep up with the degree of innovation. This paper demonstrates the reasons for the existence of this systematic challenge, and puts forward the method of UX research which is different from the traditional petrol vehicles research in the early stage of development, which studies from the user's essence level, to form the innovative product programs which meet the needs of users and being real attractive.

Pendugaan Parameter Genetik Kedelai Generasi F4 pada Intensitas Cahaya Rendah

Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Yohanis Amos Mustamu ◽  
Trikoesoemaningtyas Trikoesoemaningtyas ◽  
Desta Wirnas ◽  
Didy Sopandie ◽  
Darman M. Arsyad
Keyword(s):  
Light Intensity ◽  
Genetic Parameter ◽  
Design Experiment ◽  
Low Light ◽  
Experimental Field ◽  
High Heritability ◽  
Intensity Condition ◽  
Augmented Design ◽  
Genetic Coefficient ◽  
The University

The objective of this study was to collect information on genetic parameter and agronomy character of soybean F4 generation in the low light intensity condition. The parameter was tested to 130 lines F4 which are produced by Balai Besar Pengkajian dan Pengembangan Teknologi Pertanian (BBP2TP) Boor and the genotype of Sibayak, Tegal, Tanggamus, and Argomulyo were used as controls. The experiment was conducted in the university�s experimental field in Cikabayan, from September to December 2007. A total of 130 advance (F4) soybean lines were evaluated under shading in an augmented design experiment. The result of this study showed that all character has low genetic coefficient. The weight character of 25 grains has a considerably high heritability number in low li

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