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1

Foraging Response of Turkish Honey Bee Subspecies to Flower Color Choices and Reward Consistency  

Microsoft Academic Search

Foraging behavior of Apis mellifera caucasica, A.m. carnica and A.m. syriaca in Turkey was studied for intrinsic subspecies-based differences. Models of forager flower-color fidelity, risk sensitive\\u000a behavior and maximizing net gain were tested. Foragers were presented artificial flower patches containing blue, white and\\u000a yellow flowers. Some bees of each subspecies showed high fidelity to yellow flowers, while others favored blue

Ibrahim Cakmak; Daniel S. Song; T. Andrew Mixson; Eduardo Serrano; Meredith L. Clement; Amy Savitski; Ge’Andra Johnson; Tugrul Giray; Charles I. Abramson; John F. Barthell; Harrington Wells

2010-01-01

2

The Colors of Flowers  

NSDL National Science Digital Library

In this activity, learners perform an experiment to find out what determines a flower's color. Learners extract petal juice, use acid and base indicators, and observe chemical reactions to investigate how the amount of acid or base influences the color of a flower petal.

Science Friday

2010-01-01

3

Flower color influences insect visitation in alpine New Zealand.  

PubMed

Despite a long-standing belief that insect pollinators can select for certain flower colors, there are few experimental demonstrations that free-flying insects choose between natural flowers based on color. We investigated responses of insect visitors to experimental manipulations of flower color in the New Zealand alpine. Native syrphid flies (Allograpta and Platycheirus) and solitary bees (Hylaeus and Leioproctus) showed distinct preferences for visiting certain flower species. These responses were determined, in part, by flower color, as insects also responded to experimental manipulations of visible petal color in 7 out of 11 tests with different combinations of flower species and insect type. When preferences were detected, syrphid flies chose yellow over white petals regardless of flower species, whereas Hylaeus chose white over yellow Ourisia glandulosa. In some cases, the strength and direction of color preference depended on the context of other floral traits, in which case the response usually favored the familiar, normal combination of traits. Syrphid flies also visited in response to floral morphological traits but did not show preference based on UV reflectance. The unusually high preponderance of white flowers in the New Zealand alpine is not explained by complete generalization of flower color choice. Instead, the insect visitors show preferences based on color, including colors other than white, along with other floral traits. Furthermore, they can respond in complex ways to combinations of floral cues, suggesting that traits may act in nonadditive ways in determining pollinator visitation. PMID:20957958

Campbell, Diane R; Bischoff, Mascha; Lord, Janice M; Robertson, Alastair W

2010-09-01

4

Why sexually deceptive orchids have colored flowers  

PubMed Central

Sexually deceptive orchids provide no reward to their pollinators. Instead, they mimic the sex pheromone of receptive insect females to attract males which pollinate the flowers in mating attempts. Nearly all species of the Mediterranean orchid genus Ophrys are sexually deceptive and pollinated by solitary bees and wasps. Due to the use of a highly specific olfactory communication channel most Ophrys species have, in contrast to food deceptive or rewarding orchids, an inconspicuous greenish perianth and a dark brownish labellum. However, some species possess a bright pink or white perianth, and the functional significant of such color signals in the orchid-pollinator communication system is unknown. We recently showed that the pink perianth of Ophrys heldreichii increases the performance of its bee pollinator, males of the long-horned bee Eucera (Tetralonia) berlandi, to detect the flower at short-range. At great distances (>30 cm) from the flower, male search behavior was found to be olfactory guided and unaffected by the spectral property of the perianth, i.e., chromatic and green receptor-specific contrast. However, in the near vicinity of the flower (<30 cm), where spatial vision is sufficient to detect the flower, search time only correlated with the green receptor-specific contrast between the perianth and the background. PMID:20585505

Streinzer, Martin; Paulus, Hannes F

2010-01-01

5

Review article Color vision and color choice behavior  

E-print Network

Review article Color vision and color choice behavior of the honey bee W Backhaus Institüt für 1992; accepted 22 April 1993) Summary — A general introduction to color vision in honeybees has been presented. Documenting the current state of research in this field, the theory of color vision

Paris-Sud XI, Université de

6

The Flavonoid Pathway Regulates the Petal Colors of Cotton Flower  

PubMed Central

Although biochemists and geneticists have studied the cotton flower for more than one century, little is known about the molecular mechanisms underlying the dramatic color change that occurs during its short developmental life following blooming. Through the analysis of world cotton germplasms, we found that all of the flowers underwent color changes post-anthesis, but there is a diverse array of petal colors among cotton species, with cream, yellow and red colors dominating the color scheme. Genetic and biochemical analyses indicated that both the original cream and red colors and the color changes post-anthesis were related to flavonoid content. The anthocyanin content and the expression of biosynthesis genes were both increased from blooming to one day post-anthesis (DPA) when the flower was withering and undergoing abscission. Our results indicated that the color changes and flavonoid biosynthesis of cotton flowers were precisely controlled and genetically regulated. In addition, flavonol synthase (FLS) genes involved in flavonol biosynthesis showed specific expression at 11 am when the flowers were fully opened. The anthocyanidin reductase (ANR) genes, which are responsible for proanthocyanidins biosynthesis, showed the highest expression at 6 pm on 0 DPA, when the flowers were withered. Light showed primary, moderate and little effects on flavonol, anthocyanin and proanthocyanidin biosynthesis, respectively. Flavonol biosynthesis was in response to light exposure, while anthocyanin biosynthesis was involved in flower color changes. Further expression analysis of flavonoid genes in flowers of wild type and a flavanone 3-hydroxylase (F3H) silenced line showed that the development of cotton flower color was controlled by a complex interaction between genes and light. These results present novel information regarding flavonoids metabolism and flower development. PMID:23951318

Tan, Jiafu; Wang, Maojun; Tu, Lili; Nie, Yichun; Lin, Yongjun; Zhang, Xianlong

2013-01-01

7

Cytotoxic and bioactive properties of different color tulip flowers and degradation kinetic of tulip flower anthocyanins.  

PubMed

This study was conducted to determine the potential use of anthocyanin-based extracts (ABEs) of wasted tulip flowers as food/drug colorants. For this aim, wasted tulip flowers were samples and analyzed for their bioactive properties and cytotoxicity. Total phenolic contents of the extracts of the claret red (126.55 mg of gallic acid equivalent (GAE)/g dry extract) and orange-red (113.76 mg GAE/g dry extract) flowers were the higher than those of the other tulip flowers. Total anthocyanin levels of the violet, orange-red, claret red and pink tulip flower extracts were determined as 265.04, 236.49, 839.08 and 404.45 mg pelargonidin 3-glucoside/kg dry extract, respectively and these levels were higher than those of the other flowers. The extracts were more effective for the inhibition of Listeria monocytogenes, Staphylococcus aureus and Yersinia enterocolitica compared to other tested bacteria. Additionally, the cytotoxic effects of five different tulip flower extracts on human breast adenocarcinoma (MCF-7) cell line were investigated. The results showed that the orange red, pink and violet extracts had no cytotoxic activity against MCF-7 cell lines while yellow and claret red extracts appeared to be toxic for the cells. Overall, the extracts of tulip flowers with different colors possess remarkable bioactive and cytotoxic properties. PMID:23712096

Sagdic, Osman; Ekici, Lutfiye; Ozturk, Ismet; Tekinay, Turgay; Polat, Busra; Tastemur, Bilge; Bayram, Okan; Senturk, Berna

2013-08-01

8

A Quantitative Theory of Human Color Choices  

PubMed Central

The system for colorimetry adopted by the Commission Internationale de l’Eclairage (CIE) in 1931, along with its subsequent improvements, represents a family of light mixture models that has served well for many decades for stimulus specification and reproduction when highly controlled color standards are important. Still, with regard to color appearance many perceptual and cognitive factors are known to contribute to color similarity, and, in general, to all cognitive judgments of color. Using experimentally obtained odd-one-out triad similarity judgments from 52 observers, we demonstrate that CIE-based models can explain a good portion (but not all) of the color similarity data. Color difference quantified by CIELAB ?E explained behavior at levels of 81% (across all colors), 79% (across red colors), and 66% (across blue colors). We show that the unexplained variation cannot be ascribed to inter- or intra-individual variations among the observers, and points to the presence of additional factors shared by the majority of responders. Based on this, we create a quantitative model of a lexicographic semiorder type, which shows how different perceptual and cognitive influences can trade-off when making color similarity judgments. We show that by incorporating additional influences related to categorical and lightness and saturation factors, the model explains more of the triad similarity behavior, namely, 91% (all colors), 90% (reds), and 87% (blues). We conclude that distance in a CIE model is but the first of several layers in a hierarchy of higher-order cognitive influences that shape color triad choices. We further discuss additional mitigating influences outside the scope of CIE modeling, which can be incorporated in this framework, including well-known influences from language, stimulus set effects, and color preference bias. We also discuss universal and cultural aspects of the model as well as non-uniformity of the color space with respect to different cultural biases. PMID:23409103

Komarova, Natalia L.; Jameson, Kimberly A.

2013-01-01

9

Modeling and Visualization of Flower Color Patterns Department of Computer Science and Technology  

E-print Network

Modeling and Visualization of Flower Color Patterns Ning Zhou Department of Computer Science@mail.tsinghua.edu.cn Abstract Flowers are familiar in virtual scenes, however, the de- sign of flower patterns is still mainly done by hand. To produce a number of flower color patterns required by a large scene can be very labor

Paris-Sud XI, Université de

10

Indexing Flowers by Color Names using Domain Knowledge-driven Segmentation  

E-print Network

Indexing Flowers by Color Names using Domain Knowledge-driven Segmentation Madirakshi Das R describe a solution to the problem of indexing images of flowers for searching a flower patents database algorithm with knowledge-driven feedback to isolate a flower region from the background. The color

Massachusetts at Amherst, University of

11

Flower color–flower scent associations in polymorphic Hesperis matronalis (Brassicaceae)  

Microsoft Academic Search

Floral scent emission rate and composition of purple and white flower color morphs of Hesperis matronalis (Brassicaceae) were determined for two populations and, for each, at two times of day using dynamic headspace collection and GC–MS. The floral volatile compounds identified for this species fell into two main categories, terpenoids and aromatics. Principal component analysis of 30 compounds demonstrated that

Cassie J. Majetic; Robert A. Raguso; Stephen J. Tonsor; Tia-Lynn Ashman

2007-01-01

12

Perspective: Evolution of Flower Color in the Desert Annual Linanthus parryae: Wright Revisited  

E-print Network

of a long- standing debate among evolutionary biologists. At issue is whether the flower color polymorphismPerspective: Evolution of Flower Color in the Desert Annual Linanthus parryae: Wright Revisited(7), 2001, pp. 1269-1282 PERSPECTIVE: EVOLUTION OF FLOWER COLOR IN THE DESERT ANNUAL LINANTHUS PARRYAE

Bierzychudek, Paulette

13

Abstract It is usually assumed that the choice behavior of bees for floral colors is influenced by innate prefer-  

E-print Network

Abstract It is usually assumed that the choice behavior of bees for floral colors is influenced to rewarding flowers bees learn to as- sociate their colors with a reward. This learning process leads and over innate preferences. This work investigates how bumble bees (Bombus terrestris) chose among

Menzel, Randolf - Institut fĂĽr Biologie

14

Pollinator-Mediated Selection on Flower Color, Flower Scent and Flower Morphology of Hemerocallis: Evidence from Genotyping Individual Pollen Grains On the Stigma  

PubMed Central

To trace the fate of individual pollen grains through pollination processes, we determined genotypes of single pollen grains deposited on Hemerocallis stigmas in an experimental mixed-species array. Hemerocallis fulva, pollinated by butterflies, has diurnal, reddish and unscented flowers, and H. citrina, pollinated by hawkmoths, has nocturnal, yellowish and sweet scent flowers. We observed pollinator visits to an experimental array of 24 H. fulva and 12 F2 hybrids between the two species (H. fulva and H. citrina) and collected stigmas after every trip bout of swallowtail butterflies or hawkmoths. We then measured selection by swallowtail butterflies or hawkmoths through male and female components of pollination success as determined by single pollen genotyping. As expected, swallowtail butterflies imposed selection on reddish color and weak scent: the number of outcross pollen grains acquired is a quadratic function of flower color with the maximum at reddish color, and the combined pollination success was maximal at weak scent (almost unrecognizable for human). This explains why H. fulva, with reddish flowers and no recognizable scent, is mainly pollinated by swallowtail butterflies. However, we found no evidence of hawkmoths-mediated selection on flower color or scent. Our findings do not support a hypothesis that yellow flower color and strong scent intensity, the distinctive floral characteristics of H. citrina, having evolved in adaptations to hawkmoths. We suggest that the key trait that triggers the evolution of nocturnal flowers is flowering time rather than flower color and scent. PMID:24376890

Hirota, Shun K.; Nitta, Kozue; Suyama, Yoshihisa; Kawakubo, Nobumitsu; Yasumoto, Akiko A.; Yahara, Tetsukazu

2013-01-01

15

The Genetic Basis of a Flower Color Polymorphism in the Common Morning  

E-print Network

The Genetic Basis of a Flower Color Polymorphism in the Common Morning Glory (Ipomoea purpurea) R) is highly polymorphic for flower color. Part of this phenotypic variation is due to allelic variation at the P locus. This locus determines whether flowers will be purple or pink, where purple is dominant

Rausher, Mark D.

16

Flower color-flower scent associations in polymorphic Hesperis matronalis (Brassicaceae).  

PubMed

Floral scent emission rate and composition of purple and white flower color morphs of Hesperis matronalis (Brassicaceae) were determined for two populations and, for each, at two times of day using dynamic headspace collection and GC-MS. The floral volatile compounds identified for this species fell into two main categories, terpenoids and aromatics. Principal component analysis of 30 compounds demonstrated that both color morphs emitted more scent at dusk than at dawn. Color morphs varied in chemical composition of scent, but this differed between populations. The white morphs exhibited significant differences between populations, while the purple morphs did not. In the white morphs, one population contains color-scent associations that match expectations from classical pollination syndrome theory, where the flowers have aromatic scents, which are expected to maximize night-flying moth pollinator attraction; in the second population, white morphs were strongly associated with terpenoid compounds. The potential impact that pollinators, conserved biosynthetic pathways, and the genetics of small colonizing populations may have in determining population-specific associations between floral color and floral scent are discussed. PMID:17258250

Majetic, Cassie J; Raguso, Robert A; Tonsor, Stephen J; Ashman, Tia-Lynn

2007-03-01

17

THE ROLE OF HERBIVORES IN THE MAINTENANCE OF A FLOWER COLOR POLYMORPHISM IN WILD RADISH  

Microsoft Academic Search

Plant species exhibiting polymorphisms with respect to flower color are widespread. Our understanding of the selection pressures that may maintain these color polymorphisms has primarily been confined to one set of organisms—pollinators. Yet, selection on flower color may also be driven by other agents, such as herbivores, especially in cases where pollinators and herbivores are using the same or correlated

Rebecca E. Irwin; Sharon Y. Strauss; Shonna Storz; Aimee Emerson; Genevieve Guibert

2003-01-01

18

Arctic Mustard Flower Color Polymorphism Controlled by Petal-Specific Downregulation at the Threshold of the Anthocyanin Biosynthetic Pathway  

Microsoft Academic Search

Intra- and interspecific variation in flower color is a hallmark of angiosperm diversity. The evolutionary forces underlying the variety of flower colors can be nearly as diverse as the colors themselves. In addition to pollinator preferences, non-pollinator agents of selection can have a major influence on the evolution of flower color polymorphisms, especially when the pigments in question are also

Cynthia A. Dick; Jason Buenrostro; Timothy Butler; Matthew L. Carlson; Daniel J. Kliebenstein; Justen B. Whittall; Ivan Baxter

2011-01-01

19

Protocol for inducing flower color somaclonal variation in Torenia (Torenia fournieri Lind.).  

PubMed

White or light purple flower color Torenia (Torenia fournieri Lind.) varieties were successfully developed from the parental variety having violet flowers. This was accomplished by reducing Fe micronutrient in the culture media for the induction of in vitro flowering. The flower induction was highest in modified Murashige and Skoog (MS) medium containing ˝ strength of macroelements, microelements, organic additives, and full Fe (M1) when compared to MS medium containing ˝ strength of macronutrients, micronutrients, full Fe, and full organic additives (M2). The flower color was stable in two new Torenia varieties through three generations ex vitro. The results showed a wide range of somaclonal variation in flower colors; early flowering occurred in MS medium containing ˝ strength of macroelements, microelements, Fe, and full strength of organic additives (M3). The selection of desirable somaclones and their micropropagation in subsequent generations led to the development of new and stable Torenia lines. PMID:23179719

Nhut, Duong Tan; Hai, Nguyen Thanh; Thu, Pham Thi Minh; Thi, Nguyen Ngoc; Hien, Truong Thi Dieu; Tuan, Tran Trong; Nam, Nguyen Ba; Huy, Nguyen Phuc; Chien, Hoang Xuan; Jain, Shri Mohan

2013-01-01

20

Flower color variation: A model for the experimental study of evolution  

Microsoft Academic Search

Department of Botany and Plant Sciences, University of California, Riverside, CA 92521-0124 We review the study of flower color polymorphisms in the morning glory as a model for the analysis of adaptation. The pathway involved in the determination of flower color phenotype is traced from the molecular and genetic levels to the phenotypic level. Many of the genes that determine

Michael T. Clegg; Mary L. Durbin

2000-01-01

21

Flower color variation: A model for the experimental study of evolution  

Microsoft Academic Search

We review the study of flower color polymorphisms in the morning glory as a model for the analysis of adaptation. The pathway involved in the determination of flower color phenotype is traced from the molecular and genetic levels to the phenotypic level. Many of the genes that determine the enzymatic components of flavonoid biosynthesis are redundant, but, despite this complexity,

Michael T. Clegg; Mary L. Durbin

2000-01-01

22

A new allele of flower color gene W1 encoding flavonoid 3'5'-hydroxylase is responsible for light purple flowers in wild soybean Glycine soja  

Microsoft Academic Search

BACKGROUND: Glycine soja is a wild relative of soybean that has purple flowers. No flower color variant of Glycine soja has been found in the natural habitat. RESULTS: B09121, an accession with light purple flowers, was discovered in southern Japan. Genetic analysis revealed that the gene responsible for the light purple flowers was allelic to the W1 locus encoding flavonoid

Ryoji Takahashi; Joseph G Dubouzet; Hisakazu Matsumura; Kentaro Yasuda; Tsukasa Iwashina

2010-01-01

23

The Genetic Basis of a Rare Flower Color Polymorphism in Mimulus lewisii Provides Insight into the Repeatability  

E-print Network

The Genetic Basis of a Rare Flower Color Polymorphism in Mimulus lewisii Provides Insight of a Rare Flower Color Polymorphism in Mimulus lewisii Provides Insight into the Repeatability of Evolution are predictable. Here, we identify a genetic change associated with segregating variation in flower color within

Oregon, University of

24

The effect of flower-like and non-flower-like visual properties on choice of unrewarding patterns by bumblebees  

NASA Astrophysics Data System (ADS)

How do distinct visual stimuli help bumblebees discover flowers before they have experienced any reward outside of their nest? Two visual floral properties, type of a pattern (concentric vs radial) and its position on unrewarding artificial flowers (central vs peripheral on corolla), were manipulated in two experiments. Both visual properties showed significant effects on floral choice. When pitted against each other, pattern was more important than position. Experiment 1 shows a significant effect of concentric pattern position, and experiment 2 shows a significant preference towards radial patterns regardless of their position. These results show that the presence of markings at the center of a flower are not so important as the presence of markings that will direct bees there.

Orbán, Levente L.; Plowright, Catherine M. S.

2013-07-01

25

Usage patterns of blue flower color representation by Encyclopedia of Life content providers  

PubMed Central

Abstract Encyclopedia of Life (EOL) is a resource for community-driven biodiversity data, focusing on species information and images. Research into blue flowers to compare color ('blueness') at different elevations revealed that data content providers describe flowers as blue for any color hue in the range from blue to magenta. We propose methods for standardizing color values and color searching within EOL by means of an expanded color vocabulary and improved access to image metadata, in order to improve the research capacity of this valuable resource. PMID:25197234

Wright, Chantal-Marie

2014-01-01

26

The Genetic Basis of a Flower Color Polymorphism in the Common Morning Glory (Ipomoea purpurea)  

Microsoft Academic Search

The common morning glory (Ipomoea purpurea) is highly polymorphic for flower color. Part of this phenotypic variation is due to allelic variation at the P locus. This locus determines whether flowers will be purple or pink, where purple is dominant to pink. We have determined that the anthocyanin biosynthetic gene flavonoid 39-hydroxylase (f39h) corresponds to the P locus. In the

R. A. Zufall; M. D. RAUSHER

2003-01-01

27

Evaluation of flower color using a colorimeter and the Royal Horticultural Society charts  

Technology Transfer Automated Retrieval System (TEKTRAN)

The visual appearance of flowers, fresh fruits and vegetables is one of the first quality determinants made by the consumer. Often the appearance of the commodity is the most critical factor in the initial sale. The flower color of Amaryllis (Amaryllis Hippeastrum) cultivars at the U. S. National Ge...

28

Mapping of one of the two genes controlling lemon ray flower color in sunflower (Helianthus annuus L.)  

Technology Transfer Automated Retrieval System (TEKTRAN)

In an F2 population of 120 plants derived from a cross between two breeding lines with yellow ray flowers, we observed 111 plants with yellow- and nine plants with lemon-colored ray flowers. The segregation pattern fit a 15:1 (x2(15:1)=0.32, p>0.5) ratio, suggesting that the lemon ray flower color i...

29

Spatial differentiation for flower color in the desert annual Linanthus parryae: was Wright right?  

PubMed

Understanding the evolutionary mechanisms that contribute to the local genetic differentiation of populations is a major goal of evolutionary biology, and debate continues regarding the relative importance of natural selection and random genetic drift to population differentiation. The desert plant Linanthus parryae has played a prominent role in these debates, with nearly six decades of empirical and theoretical work into the causes of spatial differentiation for flower color. Plants produce either blue or white flowers, and local populations often differ greatly in the frequencies of the two color morphs. Sewall Wright first applied his model of "isolation by distance" to investigate spatial patterns of flower color in Linanthus. He concluded that the distribution of flower color morphs was due to random genetic drift, and that Linanthus provided an example of his shifting balance theory of evolution. Our results from comprehensive field studies do not support this view. We studied an area in which flower color changed abruptly from all-blue to all-white across a shallow ravine. Allozyme markers sampled across these regions showed no evidence of spatial differentiation, reciprocal transplant experiments revealed natural selection favoring the resident morph, and soils and the dominant members of the plant community differed between regions. These results support the hypothesis that local differences in flower color are due to natural selection, not due to genetic drift. PMID:17894812

Schemske, Douglas W; Bierzychudek, Paulette

2007-11-01

30

Bidirectional flower color and shape changes allow a second opportunity for pollination.  

PubMed

Flowers act as "sensory billboards" with multiple signals (color, morphology, odor) attracting and manipulating potential pollinators. Many use changing signals as indicators that visitation and/or pollination have occurred). Floral color change is commonly used to transmit this information (often correlated with reduced nectar reward) and can be specifically triggered by pollination or visitation. By retaining color-changed flowers, plants benefit from larger floral displays but also indicate at close range which flowers are still rewarding (and still unpollinated), so that visitors forage more efficiently. However, the legume Desmodium setigerum shows a unique ability, if inadequately pollinated, to reverse its flowers' color and shape changes. Single visits by bees mechanically depress the keel and expose stigma and anthers (termed "tripping"); visits also initiate a rapid color change from lilac to white and turquoise and a slower morphological change, the upper petal folding downwards over the reproductive parts. But flowers receiving insufficient pollen can partially reopen, re-exposing the stigma, with a further color change to deeper turquoise and/or lilac. Thus, most flowers achieve pollination from one bee visit, but those with inadequate pollen receipt can reverse their signals, earning a "second chance" by eliciting attention from other potential pollinators. PMID:19409788

Willmer, Pat; Stanley, Dara A; Steijven, Karin; Matthews, Iain M; Nuttman, Clive V

2009-06-01

31

Perspective: Evolution of flower color in the desert annual Linanthus parryae: Wright revisited.  

PubMed

Linanthus parryae, a diminutive desert annual with white or blue flowers, has been the focus of a long-standing debate among evolutionary biologists. At issue is whether the flower color polymorphism in this species is the product of random genetic drift, as Sewall Wright argued, or of natural selection, as proposed by Carl Epling and his colleagues. Our long-term studies of three polymorphic populations in the Mojave Desert demonstrate that flower color is subject to selection that varies in both time and space in its direction and magnitude. For all sites taken together, blue-flowered plants produced more seeds than white-flowered plants in years of relatively low seed production, whereas white-flowered plants had higher fitness in years of high seed production. Evidence of selection on flower color was found in two of the three study sites. Differences in fitness between the color morphs were sometimes large, with selection coefficients as high as 0.60 in some years. Our longest period of observations was at Pearblossom site 1, where plants reached appreciable densities in seven of the 11 years of study. Here we found significant differences in the seed production of the color morphs in six years, with three years of blue advantage and three years of white advantage. For all sites taken together, total spring precipitation (March and April) was positively correlated with both absolute and relative seed production of the color morphs. At Pearblossom site 1, blue-flowered plants typically had a fitness advantage in years of low spring precipitation, whereas white-flowered plants had a fitness advantage in years of high spring precipitation. This temporal variation in selection may contribute to the maintenance of the flower-color polymorphism at Pearblossom site 1, whereas gene flow from neighboring populations is proposed as the principal factor maintaining the polymorphism at the other study sites. We found no significant differences between the color morphs in pollinator visitation rate or in their carbon isotope ratio, a measure of water-use efficiency. Although the mechanism of selection remains elusive, our results refute Wright's conclusion that the flower color polymorphism in L. parryae is an example of isolation by distance, a key component of his shifting balance theory of evolution. PMID:11525452

Schemske, D W; Bierzychudek, P

2001-07-01

32

Herbivore pressure by weevils associated with flower color polymorphism in Geranium thunbergii (Geraniaceae).  

PubMed

Although floral herbivory has recently received increased attention as an important factor influencing plant reproduction, relatively little is known about how its frequency and intensity vary depending on traits of host plants. Here we report that herbivore pressure by a weevil, Zacladus geranii, is associated with a flower color polymorphism of Geranium thunbergii (Geraniaceae). Pink and white flower color morphs have been reported in G. thunbergii, and we found in a three-year field survey in multiple populations that, generally, adult weevils more preferentially visited white flowers than pink flowers. Consistently, we found more severe damage by weevil larvae in white flowers. Overall herbivore pressure for G. thunbergii varied strongly between populations, and the difference seems to be partly explained by the co-occurrence of a related plant species, Geranium yezoense, in a population, as weevils preferred it to both color morphs of G. thunbergii, thereby relaxing overall herbivore pressure for G. thunbergii. Nonetheless, despite such high variability, the preference of weevils for white morphs over pink morphs of G. thunbergii was found across multiple populations. We discuss possible mechanisms causing the association between flower color and herbivore preference as well as its evolutionary consequences. PMID:24253757

Tsuchimatsu, Takashi; Yoshitake, Hiraku; Ito, Motomi

2014-03-01

33

Competition for hummingbird pollination shapes flower color variation in Andean solanaceae.  

PubMed

One classic explanation for the remarkable diversity of flower colors across angiosperms involves evolutionary shifts among different types of pollinators with different color preferences. However, the pollinator shift model fails to account for the many examples of color variation within clades that share the same pollination system. An alternate explanation is the competition model, which suggests that color divergence evolves in response to interspecific competition for pollinators, as a means to decrease interspecific pollinator movements. This model predicts color overdispersion within communities relative to null assemblages. Here, we combine morphometric analyses, field surveys, and models of pollinator vision with a species-level phylogeny to test the competition model in the primarily hummingbird-pollinated clade Iochrominae (Solanaceae). Results show that flower color as perceived by pollinators is significantly overdispersed within sites. This pattern is not simply due to phylogenetic history: phylogenetic community structure does not deviate from random expectations, and flower color lacks phylogenetic signal. Moreover, taxa that occur in sympatry occupy a significantly larger volume of color space than those in allopatry, supporting the hypothesis that competition in sympatry drove the evolution of novel colors. We suggest that competition among close relatives may commonly underlie floral divergence, especially in species-rich habitats where congeners frequently co-occur. PMID:24766107

Muchhala, Nathan; Johnsen, Sönke; Smith, Stacey Dewitt

2014-08-01

34

Male mate choice selects for female coloration in a fish  

PubMed Central

Although sexual selection theory has proved successful in explaining a wide array of male ornaments, the function of ornaments occurring in females is largely unknown. Traditionally, female ornaments have been considered nonfunctional, being merely a genetically correlated response to selection for male ornamentation. However, this hypothesis is only relevant to species in which the ornament is basically the same in the two sexes. Alternatively, female ornaments may be influenced by selection acting directly on the females, either through female–female competition or male choice. We tested the latter hypothesis in mate-choice experiments with two-spotted gobies (Gobiusculus flavescens). In this small marine fish, females have bright yellow-orange bellies during the breeding season, a conspicuous trait that is not present in males. We conducted two aquarium experiments to test whether males preferred to mate with more colorful females. In the first experiment, males had a choice between two females that varied in natural coloration (and belly roundness). In the second experiment, we manipulated belly coloration and kept roundness constant. Males spent more time with colorful than with drab females in both experiments and also performed far more courtship displays toward colorful females. Our study provides experimental evidence that males prefer ornamented females in a fish that is not sex-role reversed, supporting the hypothesis that female ornamentation is sexually selected. PMID:11606720

Amundsen, Trond; Forsgren, Elisabet

2001-01-01

35

Flower color polymorphism in Iris lutescens (Iridaceae): biochemical analyses in light of plant-insect interactions.  

PubMed

We describe a flower color polymorphism in Iris lutescens, a species widespread in the Northern part of the Mediterranean basin. We studied the biochemical basis of the difference between purple and yellow flowers, and explored the ecological and evolutionary consequences of such difference, in particular visual discrimination by insects, a potential link with scent emitted and the association between color and scent. Anthocyanins were found to be present in much greater concentrations in purple flowers than in yellow ones, but the anthocyanin composition did not differ between color morphs. Likewise, no quantitative difference in anthocyanin content was found between vegetative tissues of the two morphs. Floral anthocyanins were dominated by delphinidin 3-O-(p-coumaroylrutinoside)-5-O-glucoside (also called delphanin) and its aliphatic derivatives. Small amounts of delphinidin 3-O-(p-caffeoylrutinoside)-5-O-glucoside and its aliphatic derivatives were also characterized. Based on a description of bumblebees' (one of the main pollinators of I. lutescens) color perception, purple and yellow flowers of I. lutescens could be visually discriminated as blue and blue-green, respectively, and likely by a wide variety of other insects. The overall chemical composition of the scent produced was not significantly different between morphs, being dominated by terpenoids, mainly myrcene, (E)-?-ocimene and limonene. A slight color-scent correlation was nevertheless detected, consistent with the shared biosynthetic origin of both pigments and volatile compounds. Therefore in this species, the difference in the amounts of pigments responsible for flower color difference seems to be the major difference between the two morphs. Pollinators are probably the main selective agent driving the evolution of flower color polymorphism in I. lutescens, which represents a suitable species for investigating how such polymorphism is maintained. PMID:23790644

Wang, Hui; Conchou, Lucie; Bessičre, Jean-Marie; Cazals, Guillaume; Schatz, Bertrand; Imbert, Eric

2013-10-01

36

Comparing Distributions of Color Words: Pitfalls and Metric Choices  

PubMed Central

Computational methods have started playing a significant role in semantic analysis. One particularly accessible area for developing good computational methods for linguistic semantics is in color naming, where perceptual dissimilarity measures provide a geometric setting for the analyses. This setting has been studied first by Berlin & Kay in 1969, and then later on by a large data collection effort: the World Color Survey (WCS). From the WCS, a dataset on color naming by 2 616 speakers of 110 different languages is made available for further research. In the analysis of color naming from WCS, however, the choice of analysis method is an important factor of the analysis. We demonstrate concrete problems with the choice of metrics made in recent analyses of WCS data, and offer approaches for dealing with the problems we can identify. Picking a metric for the space of color naming distributions that ignores perceptual distances between colors assumes a decorrelated system, where strong spatial correlations in fact exist. We can demonstrate that the corresponding issues are significantly improved when using Earth Mover's Distance, or Quadratic -square Distance, and we can approximate these solutions with a kernel-based analysis method. PMID:24586580

Vejdemo-Johansson, Mikael; Vejdemo, Susanne; Ek, Carl-Henrik

2014-01-01

37

Flower choice by naďve young crab spiders and the effect of subsequent experience.  

PubMed

Initial responses of naďve individuals to critical environmental stimuli provide important information about the innate contribution to behaviour, and subsequent responses to the same stimuli may show the role of experience in mediating those initial responses. To test the role of these factors, I measured initial patch choices and giving-up responses of just-emerged, naďve, second-instar crab spiders, Misumena vatia, on several hunting sites they encountered after leaving their natal nests. In follow-up tests I measured the effects of these experiences on subsequent patch choice decisions. The choice of hunting sites is a vital decision at all stages of the life cycle for sit-and-wait predators such as Misumena. In their initial tests these spiderlings remained more frequently on goldenrod (Solidago spp.) flowers than on green or yellow goldenrod buds, a preference they retained through tests run on 5 consecutive days. Individuals on green and yellow buds shifted sites more quickly and frequently than those from flowers, and made most of these moves to flowers, which attracted many more prey than did buds. These differences were not affected by age, energetic condition, or loss of information over the period of the experiment. Once spiderlings moved from buds, they showed a high, increasing tendency to move from buds in subsequent runs, those from flowers showed a consistently low tendency. These results suggest that spiderlings retain their innate behavioural patterns through the second instar, but that experience also plays a modest role in patch choice at this stage. Copyright 2000 The Association for the Study of Animal Behaviour. PMID:10860521

Morse

2000-05-01

38

Does flower color variation matter in deception pollinated Psychilis monensis (Orchidaceae)?  

PubMed

Negative frequency dependent selection (FDS) had been proposed as a mechanism for the maintenance of the high levels of variability in floral traits of rewardless plants. Thus far the evidence has been equivocal for discontinuous traits. We experimentally tested the FDS hypothesis for continuous variation in flower color of Psychilis monensis, a rewardless, epiphytic orchid of Mona Island, Puerto Rico. P. monensis flowers all year long with a peak in June and July. Plants are self-incompatible. Individual flowers last 9-15 days if unpollinated. Over a 9-month observation of an unmanipulated population, a high percentage of plants showed pollinarium removals (79%) and fruit initiation (63%), but the actual percentage of flowers visited was very low (12%) and final fruit set was as low as the lowest recorded for orchids (2.4%). In a FDS experiment using a Latin Square design, we manipulated flower color in three populations. Over 50% of the variation in either male or female reproductive success was explained by time and site with no significant effect of treatment except as part of a three-way interaction of time x site x treatment. Paired comparisons with the controls gave equivocal results for both male and female measures of reproductive success. Major community changes had occurred during the FDS experiment with flower activity falling dramatically and by the third run of the experiment, only P. monensis was in flower. Coincidentally, the numbers of effective visits increased with time, presumably as pollinators became less discriminating in search of new food resources. Thus, negative frequency dependent selection is either sporadic or non-existent. Reproductive success was statistically related to locality and date, which was reflected in the flowering phenology of the local communities. High natural levels of color variation may be more influenced by drift than selection. PMID:14666418

Aragón, Susan; Ackerman, James D

2004-02-01

39

Flower color as a model system for studies of plant evo-devo  

PubMed Central

Even though pigmentation traits have had substantial impacts on the field of animal evolutionary developmental biology, they have played only relatively minor roles in plant evo-devo. This is surprising given the often direct connection between flower color and fitness variation mediated through the effects of pollinators. At the same time, ecological and evolutionary genetic studies have utilized the molecular resources available for the anthocyanin pathway to generate several examples of the molecular basis of putatively adaptive transitions in flower color. Despite this opportunity to synthesize experimental approaches in ecology, evolution, and developmental biology, the investigation of many fundamental questions in evo-devo using this powerful model is only at its earliest stages. For example, a long-standing question is whether predictable genetic changes accompany the repeated evolution of a trait. Due to the conserved nature of the biochemical and regulatory control of anthocyanin biosynthesis, it has become possible to determine whether, and under what circumstances, different types of mutations responsible for flower color variation are preferentially targeted by natural selection. In addition, because plants use anthocyanin and related compounds in vegetative tissue for other important physiological functions, the identification of naturally occurring transitions from unpigmented to pigmented flowers provides the opportunity to examine the mechanisms by which regulatory networks are co-opted into new developmental domains. Here, we review what is known about the ecological and molecular basis of anthocyanic flower color transitions in natural systems, focusing on the evolutionary and developmental features involved. In doing so, we provide suggestions for future work on this trait and suggest that there is still much to be learned from the evolutionary development of flower color transitions in nature. PMID:23970892

Sobel, James M.; Streisfeld, Matthew A.

2013-01-01

40

Molecular analysis of the anthocyanin2 gene of petunia and its role in the evolution of flower color  

Microsoft Academic Search

The shape and color of flowers are important for plant reproduction because they attract pollinators such as insects and birds. Therefore, it is thought that alterations in these traits may result in the attraction of different pollinators, ge- netic isolation, and ultimately, (sympatric) speciation. Petunia integrifolia and P. axillaris bear flowers with different shapes and colors that appear to be

Francesca Quattrocchio; John Wing; Karel van der Woude; Erik Souer; Nick de Vetten; Joseph Mol

1999-01-01

41

Blue metal complex pigments involved in blue flower color  

PubMed Central

The blue pigment of cornflower, protocyanin, has been investigated for a long time, but its precise structure was not entirely explained until recently. The molecular structure of the pigment was recently shown to be a metal complex of six molecules each of anthocyanin and flavone glycoside, with one ferric iron, one magnesium and two calcium ions by X-ray crystallographic analysis. The studies provided the answer to the question posed in the early part of the last century, “why is the cornflower blue and rose red when both flowers contain the same anthocyanin?” This work was achieved on the basis of the results of long years of the studies made by many researchers. In this review, the author focuses on the investigations of the blue metal complex pigments involved in the bluing of flowers, commelinin from Commelina commusis, protocyanin from Centaurea cyanus, protodelphin from Salvia patens and hydrangea blue pigment.

Takeda, Kosaku

2006-01-01

42

Negative frequency-dependent selection maintains a dramatic flower color polymorphism in the rewardless orchid Dactylorhiza sambucina (L.) Soň  

Microsoft Academic Search

The orchid Dactylorhiza sambucina shows a stable and dramatic flower-color polymorphism, with both yellow- and purple-flowered individuals present in natural populations throughout the range of the species in Europe. The evolutionary significance of flower-color polymorphisms found in many rewardless orchid species has been discussed at length, but the mechanisms responsible for their maintenance remain unclear. Laboratory experiments have suggested that

Luc D. B. Gigord; Mark R. MacNair; Ann Smithson

2001-01-01

43

Gene Loss and Parallel Evolution Contribute to Species Difference in Flower Color  

PubMed Central

Although the importance of regulatory and functional sequence evolution in generating species differences has been studied to some extent, much less is known about the role of other types of genomic changes, such as fluctuation in gene copy number. Here, we apply analyses of gene function and expression of anthocyanin pigment pathway genes, as well as cosegregation analyses in backcross populations, to examine the genetic changes involved in the shift from blue to red flowers in Andean Iochroma (Solanaceae). We demonstrate that deletion of a gene coding for an anthocyanin pathway enzyme was necessary for the transition to red floral pigmentation. The downregulation of a second pathway gene was also necessary for the novel flower color, and this regulatory pattern parallels the genetic change in the two other red-flowered species in the sister family Convolvulaceae in which flower color change has been examined genetically. Finally, we document a shift in enzymatic function at a third locus, but the importance of this change in the transition to red flowers depends on the exact order with which the three changes occurred. This study shows that gene inactivation or loss can be involved in the origin of phenotypic differences between species, thereby restricting the possibility of reversion to the ancestral state. It also demonstrates that parallel evolution of red flowers in three different species occurs via a common developmental/regulatory change but by mutations in different genes. PMID:21551271

Smith, Stacey D.; Rausher, Mark D.

2011-01-01

44

Pollinator-Mediated Selection on a Flower Color Polymorphism in Experimental Populations of Antirrhinum (Scrophulariaceae)  

Microsoft Academic Search

We quantified pollinator visit behavior, pollen receipt and export, and changes in allele and genotype frequencies from initial Hardy- Weinberg conditions in experimental arrays of two color morphs of snapdragons (Antirrhinum majus) visited by freely foraging bumble bees (Bombus appositus and B. flavifrons). The number of pollen grains received by a flower depended most on the number of pollinator visits

Kristina Niovi Jones; Jennifer S. Reithel

2001-01-01

45

Current Biology 19, 919923, June 9, 2009 2009 Elsevier Ltd All rights reserved DOI 10.1016/j.cub.2009.03.070 Bidirectional Flower Color  

E-print Network

.cub.2009.03.070 Report Bidirectional Flower Color and Shape Changes Allow a Second Opportunity Flowers act as ``sensory billboards'' with multiple signals (color, morphology, odor) attracting or visi- tation. By retaining color-changed flowers, plants benefit from larger floral displays but also

Papaj, Daniel

46

Pollinator-mediated selection on a flower color polymorphism in experimental populations of Antirrhinum (Scrophulariaceae).  

PubMed

We quantified pollinator visit behavior, pollen receipt and export, and changes in allele and genotype frequencies from initial Hardy- Weinberg conditions in experimental arrays of two color morphs of snapdragons (Antirrhinum majus) visited by freely foraging bumble bees (Bombus appositus and B. flavifrons). The number of pollen grains received by a flower depended most on the number of pollinator visits to the flower, whereas the number of grains exported was best predicted by the total time pollinators spent inside the flower. The pattern of mating generally was assortative with respect to color, as bees tended to overvisit one color or the other within a foraging bout. In arrays where nectar was augmented in one color, the augmented color received both more visits and longer visits. Allele and genotype frequencies in offspring samples were in accord with qualitative expectations based on the pollinator observations, demonstrating that pollinators can directly influence the evolution of single-locus floral traits, at least under simplified experimental conditions. PMID:11250822

Niovi Jones, K; Reithel, J S

2001-03-01

47

Predictability and irreversibility of genetic changes associated with flower color evolution in Penstemon barbatus.  

PubMed

Two outstanding questions in evolutionary biology are whether, and how often, the genetic basis of phenotypic evolution is predictable; and whether genetic change constrains evolutionary reversibility. We address these questions by studying the genetic basis of red flower color in Penstemon barbatus. The production of red flowers often involves the inactivation of one or both of two anthocyanin pathway genes, Flavonoid 3',5'-hydroxylase (F3'5'h) and Flavonoid 3'-hydroxylase (F3'h). We used gene expression and enzyme function assays to determine that redundant inactivating mutations to F3'5'h underlie the evolution of red flowers in P. barbatus. Comparison of our results to previously characterized shifts from blue to red flowers suggests that the genetic change associated with the evolution of red flowers is predictable: when it involves elimination of F3'5'H activity, functional inactivation or deletion of this gene tends to occur; however, when it involves elimination of F3'H activity, tissue-specific regulatory substitutions occur and the gene is not functionally inactivated. This pattern is consistent with emerging data from physiological experiments indicating that F3'h may have pleiotropic effects and is thus subject to purifying selection. The multiple, redundant inactivating mutations to F3'5'h suggest that reversal to blue-purple flowers in this group would be unlikely. PMID:24350572

Wessinger, Carolyn A; Rausher, Mark D

2014-04-01

48

The genetic basis of a flower color polymorphism in the common morning glory (Ipomoea purpurea).  

PubMed

The common morning glory (Ipomoea purpurea) is highly polymorphic for flower color. Part of this phenotypic variation is due to allelic variation at the P locus. This locus determines whether flowers will be purple or pink, where purple is dominant to pink. We have determined that the anthocyanin biosynthetic gene flavonoid 3'-hydroxylase (f3'h) corresponds to the P locus. In the pink allele of f3'h there is a large insertion in the third exon, which results in the production of a truncated transcript. This shortened transcript produces a nonfunctional F3'H enzyme, resulting in the production of pink flowers rather than purple. In addition, we describe a polymerase chain reaction (PCR)-based assay that can be used to determine the genotype of a plant at this locus. PMID:14691310

Zufall, R A; Rausher, M D

2003-01-01

49

Arctic Mustard Flower Color Polymorphism Controlled by Petal-Specific Downregulation at the Threshold of the Anthocyanin Biosynthetic Pathway  

PubMed Central

Intra- and interspecific variation in flower color is a hallmark of angiosperm diversity. The evolutionary forces underlying the variety of flower colors can be nearly as diverse as the colors themselves. In addition to pollinator preferences, non-pollinator agents of selection can have a major influence on the evolution of flower color polymorphisms, especially when the pigments in question are also expressed in vegetative tissues. In such cases, identifying the target(s) of selection starts with determining the biochemical and molecular basis for the flower color variation and examining any pleiotropic effects manifested in vegetative tissues. Herein, we describe a widespread purple-white flower color polymorphism in the mustard Parrya nudicaulis spanning Alaska. The frequency of white-flowered individuals increases with increasing growing-season temperature, consistent with the role of anthocyanin pigments in stress tolerance. White petals fail to produce the stress responsive flavonoid intermediates in the anthocyanin biosynthetic pathway (ABP), suggesting an early pathway blockage. Petal cDNA sequences did not reveal blockages in any of the eight enzyme-coding genes in white-flowered individuals, nor any color differentiating SNPs. A qRT-PCR analysis of white petals identified a 24-fold reduction in chalcone synthase (CHS) at the threshold of the ABP, but no change in CHS expression in leaves and sepals. This arctic species has avoided the deleterious effects associated with the loss of flavonoid intermediates in vegetative tissues by decoupling CHS expression in petals and leaves, yet the correlation of flower color and climate suggests that the loss of flavonoids in the petals alone may affect the tolerance of white-flowered individuals to colder environments. PMID:21490971

Dick, Cynthia A.; Buenrostro, Jason; Butler, Timothy; Carlson, Matthew L.; Kliebenstein, Daniel J.; Whittall, Justen B.

2011-01-01

50

Arctic mustard flower color polymorphism controlled by petal-specific downregulation at the threshold of the anthocyanin biosynthetic pathway.  

PubMed

Intra- and interspecific variation in flower color is a hallmark of angiosperm diversity. The evolutionary forces underlying the variety of flower colors can be nearly as diverse as the colors themselves. In addition to pollinator preferences, non-pollinator agents of selection can have a major influence on the evolution of flower color polymorphisms, especially when the pigments in question are also expressed in vegetative tissues. In such cases, identifying the target(s) of selection starts with determining the biochemical and molecular basis for the flower color variation and examining any pleiotropic effects manifested in vegetative tissues. Herein, we describe a widespread purple-white flower color polymorphism in the mustard Parrya nudicaulis spanning Alaska. The frequency of white-flowered individuals increases with increasing growing-season temperature, consistent with the role of anthocyanin pigments in stress tolerance. White petals fail to produce the stress responsive flavonoid intermediates in the anthocyanin biosynthetic pathway (ABP), suggesting an early pathway blockage. Petal cDNA sequences did not reveal blockages in any of the eight enzyme-coding genes in white-flowered individuals, nor any color differentiating SNPs. A qRT-PCR analysis of white petals identified a 24-fold reduction in chalcone synthase (CHS) at the threshold of the ABP, but no change in CHS expression in leaves and sepals. This arctic species has avoided the deleterious effects associated with the loss of flavonoid intermediates in vegetative tissues by decoupling CHS expression in petals and leaves, yet the correlation of flower color and climate suggests that the loss of flavonoids in the petals alone may affect the tolerance of white-flowered individuals to colder environments. PMID:21490971

Dick, Cynthia A; Buenrostro, Jason; Butler, Timothy; Carlson, Matthew L; Kliebenstein, Daniel J; Whittall, Justen B

2011-01-01

51

Flower choice by honey bees ( Apis mellifera L.): sex-phase of flowers and preferences among nectar and pollen foragers  

Microsoft Academic Search

Bees foraging for nectar should choose different inflorescences from those foraging for both pollen and nectar, if inflorescences consist of differing proportions of male and female flowers, particularly if the sex phases of the flowers differ in nectar content as well as the occurrence of pollen. This study tested this prediction using worker honey bees (Apis mellifera L.) foraging on

A. Gonzalez; C. L. Rowe; D. Whittle; F. S. Gilbert; C. J. Barnard

1995-01-01

52

Mapping one of the 2 genes controlling lemon ray flower color in sunflower (Helianthus annuus L.).  

PubMed

In an F2 population of 120 plants derived from a cross between 2 breeding lines with yellow ray flowers, we observed 111 plants with yellow-colored and 9 plants with lemon-colored ray flowers. The segregation pattern fits a 15:1 (chi2(15:1) = 0.32, P > 0.5) ratio, suggesting that the lemon ray flower color is conditioned by 2 independent recessive genes that had been contributed individually by each of the parents. We sampled 111 plants from the 3 F(2:3) families displaying a 3 to 1 segregating ratio for genotyping with molecular markers. One of the genes, Yf(1), was mapped onto linkage group 11 of the public sunflower map. A targeted region amplified polymorphism marker (B26P17Trap13-68) had a genetic distance of 1.5 cM to Yf(1), and one simple sequence repeat marker (ORS733) and one expressed sequence tag (EST)-based marker (HT167) previously mapped to linkage group 11 were linked to Yf(1) with distances of 9.9 and 2.3 cM, respectively. PMID:18477587

Yue, Bing; Vick, Brady A; Yuan, Wenge; Hu, Jinguo

2008-01-01

53

Stability of flower colors due to anthocyanin-flavone copigmentation in Japanese garden iris, Iris ensata Thunb  

Microsoft Academic Search

The fading of flower color in bluish purple and reddish purple cultivars of Iris ensata and the in vitro stability of malvidin 3RGac5Gand petunidin 3RGac5G due to copigmentation with isovetixin under different pH conditions were\\u000a examined. The bluish purple cultivars exhibited higher flower color stability than the reddish purple cultivars 2 days after\\u000a anthesis. In the absence of isovitexin, malvidin

T. Yabuya; M. Saito; T. Iwashina; M. Yamaguchi

2000-01-01

54

Negative frequency-dependent selection maintains a dramatic flower color polymorphism in the rewardless orchid Dactylorhiza sambucina (L.) Soo  

Microsoft Academic Search

The orchid Dactylorhiza sambucina shows a stable and dramatic flower-color polymorphism, with both yellow- and purple-flow- ered individuals present in natural populations throughout the range of the species in Europe. The evolutionary significance of flower-color polymorphisms found in many rewardless orchid species has been discussed at length, but the mechanisms respon- sible for their maintenance remain unclear. Laboratory experi- ments

Luc D. B. Gigord; Mark R. Macnair; Ann Smithson

2001-01-01

55

Relationship between the Composition of Flavonoids and Flower Colors Variation in Tropical Water Lily (Nymphaea) Cultivars  

PubMed Central

Water lily, the member of the Nymphaeaceae family, is the symbol of Buddhism and Brahmanism in India. Despite its limited researches on flower color variations and formation mechanism, water lily has background of blue flowers and displays an exceptionally wide diversity of flower colors from purple, red, blue to yellow, in nature. In this study, 34 flavonoids were identified among 35 tropical cultivars by high-performance liquid chromatography (HPLC) with photodiode array detection (DAD) and electrospray ionization mass spectrometry (ESI-MS). Among them, four anthocyanins: delphinidin 3-O-rhamnosyl-5-O-galactoside (Dp3Rh5Ga), delphinidin 3-O-(2?-O-galloyl-6?-O-oxalyl-rhamnoside) (Dp3galloyl-oxalylRh), delphinidin 3-O-(6?-O-acetyl-?-glucopyranoside) (Dp3acetylG) and cyanidin 3- O-(2?-O-galloyl-galactopyranoside)-5-O-rhamnoside (Cy3galloylGa5Rh), one chalcone: chalcononaringenin 2?-O-galactoside (Chal2?Ga) and twelve flavonols: myricetin 7-O-rhamnosyl-(1?2)-rhamnoside (My7RhRh), quercetin 7-O-galactosyl-(1?2)-rhamnoside (Qu7GaRh), quercetin 7-O-galactoside (Qu7Ga), kaempferol 7-O-galactosyl-(1?2)-rhamnoside (Km7GaRh), myricetin 3-O-galactoside (My3Ga), kaempferol 7-O-galloylgalactosyl-(1?2)-rhamnoside (Km7galloylGaRh), myricetin 3-O-galloylrhamnoside (My3galloylRh), kaempferol 3-O-galactoside (Km3Ga), isorhamnetin 7-O-galactoside (Is7Ga), isorhamnetin 7-O-xyloside (Is7Xy), kaempferol 3-O-(3?-acetylrhamnoside) (Km3-3?acetylRh) and quercetin 3-O-acetylgalactoside (Qu3acetylGa) were identified in the petals of tropic water lily for the first time. Meanwhile a multivariate analysis was used to explore the relationship between pigments and flower color. By comparing, the cultivars which were detected delphinidin 3-galactoside (Dp3Ga) presented amaranth, and detected delphinidin 3?-galactoside (Dp3?Ga) presented blue. However, the derivatives of delphinidin and cyanidin were more complicated in red group. No anthocyanins were detected within white and yellow group. At the same time a possible flavonoid biosynthesis pathway of tropical water lily was presumed putatively. These studies will help to elucidate the evolution mechanism on the formation of flower colors and provide theoretical basis for outcross breeding and developing health care products from this plant. PMID:22485167

Zhu, Manlan; Zheng, Xuchen; Shu, Qingyan; Li, Hui; Zhong, Peixing; Zhang, Huijin; Xu, Yanjun; Wang, Lijin; Wang, Liangsheng

2012-01-01

56

The genetic basis of a rare flower color polymorphism in Mimulus lewisii provides insight into the repeatability of evolution.  

PubMed

A long-standing question in evolutionary biology asks whether the genetic changes contributing to phenotypic evolution are predictable. Here, we identify a genetic change associated with segregating variation in flower color within a population of Mimulus lewisii. To determine whether these types of changes are predictable, we combined this information with data from other species to investigate whether the spectrum of mutations affecting flower color transitions differs based on the evolutionary time-scale since divergence. We used classic genetic techniques, along with gene expression and population genetic approaches, to identify the putative, loss-of-function mutation that generates rare, white flowers instead of the common, pink color in M. lewisii. We found that a frameshift mutation in an anthocyanin pathway gene is responsible for the white-flowered polymorphism found in this population of M. lewisii. Comparison of our results with data from other species reveals a broader spectrum of flower color mutations segregating within populations relative to those that fix between populations. These results suggest that the genetic basis of fixed differences in flower color may be predictable, but that for segregating variation is not. PMID:24312531

Wu, Carrie A; Streisfeld, Matthew A; Nutter, Laura I; Cross, Kaitlyn A

2013-01-01

57

Penstemons are flowering perennials much loved by the gardening public. Gardeners appreciate their diversity of flower colors that are at peak bloom in June and July,  

E-print Network

even rebloom for seasonlong color. Hot rock penstemon (Penstemon deustus) (Fig. 5) is one of the fewP A G B G Penstemons are flowering perennials much loved by the gardening public. Gardeners some in your own garden. Most people don't realize there are about 280 species of penstemon, all na ve

58

Achievements and perspectives in biochemistry concerning anthocyanin modification for blue flower coloration.  

PubMed

Genetic engineering of roses and other plants of floricultural importance to give them a truly blue petal color is arguably one of the holy grails of plant biotechnology. Toward this goal, bluish carnations and roses were previously engineered by establishing an exclusive accumulation of delphinidin (Dp)-type anthocyanins in their petals via the heterologous expression of a flavonoid 3',5'-hydroxylase gene. Very recently, purple-blue varieties of chrysanthemums were also genetically engineered via a similar biochemical strategy. Although the floral colors of these transgenic plants still lack a true blue color, the basis for the future molecular breeding of truly blue flowers is via the engineering of anthocyanin pathways. Anthocyanins with multiple aromatic acyl groups (often referred to as polyacylated anthocyanins) in the 3'- or 7-position tend to display a more stable blue color than non-acylated anthocyanins. The 7-polyacylation process during the biosynthesis of purple-blue anthocyanins in delphinium (Delphinium grandiflorum) was found to occur in vacuoles using acyl-glucose as both the glucosyl and acyl donor. Glucosyltransferases and acyltransferases involved in anthocyanin 7-polyacylation in delphinium are vacuolar acyl-glucose-dependent enzymes belonging to the glycoside hydrolase family 1 and serine carboxypeptidae-like protein family, respectively. The 7-polyacylation proceeds through the alternate glucosylation and p-hydroxybenzoylation catalyzed by these enzymes. p-Hydroxybenzoyl-glucose serves as the p-hydroxybenzoyl and glucosyl donor to produce anthocyanins modified with a p-hydroxybenzoyl-glucose concatemer at the 7-position. This novel finding has provided a potential breakthrough for the genetic engineering of truly blue flowers, where polyacylated Dp-type anthocyanins are accumulated exclusively in the petals. PMID:25015943

Sasaki, Nobuhiro; Nakayama, Toru

2015-01-01

59

Negative frequency-dependent selection maintains a dramatic flower color polymorphism in the rewardless orchid Dactylorhiza sambucina (L.) Soo.  

PubMed

The orchid Dactylorhiza sambucina shows a stable and dramatic flower-color polymorphism, with both yellow- and purple-flowered individuals present in natural populations throughout the range of the species in Europe. The evolutionary significance of flower-color polymorphisms found in many rewardless orchid species has been discussed at length, but the mechanisms responsible for their maintenance remain unclear. Laboratory experiments have suggested that behavioral responses by pollinators to lack of reward availability might result in a reproductive advantage for rare-color morphs. Consequently, we performed an experiment varying the relative frequency of the two color morphs of D. sambucina to test whether rare morph advantage acted in the natural habitat of the species. We show here clear evidence from this manipulative experiment that rare-color morphs have reproductive advantage through male and female components. This is the first demonstration, to our knowledge, that negative frequency-dependent selection through pollinator preference for rare morphs can cause the maintenance of a flower-color polymorphism. PMID:11353863

Gigord, L D; Macnair, M R; Smithson, A

2001-05-22

60

Evaluating the spectral discrimination capabilities of different pollinators and their effect on the evolution of flower colors  

PubMed Central

Important plant pollinators like bees and birds have very different color visual systems. Previous work has attempted to relate flower syndromes to the respective visual capabilities of the most important pollinators, but has often been limited by the lack of robust means to make between-species comparisons of how flower color signals are processed. In a recent study we solved this dilemma by comparing the raw spectral signals, quantifiable by major inflection points on a wavelength scale, from different flowers whose pollinators were known from direct observation. Here we elaborate on how this method allows robust cross species comparisons that are independent of the requirement to know the complex and often inaccessible physiological data about color processing in different animals. The use of this method should thus allow for the testing of pollinator syndrome hypotheses for different animal pollinators from different regions of the world. PMID:23713140

Shrestha, Mani; Dyer, Adrian G.; Burd, Martin

2013-01-01

61

Relative Role of Flower Color and Scent on Pollinator Attraction: Experimental Tests using F1 and F2 Hybrids of Daylily and Nightlily  

PubMed Central

The daylily (Hemerocallis fulva) and nightlily (H. citrina) are typical examples of a butterfly-pollination system and a hawkmoth-pollination system, respectively. H. fulva has diurnal, reddish or orange-colored flowers and is mainly pollinated by diurnal swallowtail butterflies. H. citrina has nocturnal, yellowish flowers with a sweet fragrance and is pollinated by nocturnal hawkmoths. We evaluated the relative roles of flower color and scent on the evolutionary shift from a diurnally flowering ancestor to H. citrina. We conducted a series of experiments that mimic situations in which mutants differing in either flower color, floral scent or both appeared in a diurnally flowering population. An experimental array of 6×6 potted plants, mixed with 24 plants of H. fulva and 12 plants of either F1 or F2 hybrids, were placed in the field, and visitations of swallowtail butterflies and nocturnal hawkmoths were recorded with camcorders. Swallowtail butterflies preferentially visited reddish or orange-colored flowers and hawkmoths preferentially visited yellowish flowers. Neither swallowtail butterflies nor nocturnal hawkmoths showed significant preferences for overall scent emission. Our results suggest that mutations in flower color would be more relevant to the adaptive shift from a diurnally flowering ancestor to H. citrina than that in floral scent. PMID:22720016

Hirota, Shun K.; Nitta, Kozue; Kim, Yuni; Kato, Aya; Kawakubo, Nobumitsu; Yasumoto, Akiko A.; Yahara, Tetsukazu

2012-01-01

62

Flower Engineers  

NSDL National Science Digital Library

This activity (on pages 24-29) combines science and art to introduce learners to how different animal pollinators spread pollen from one plant to another, and how certain shapes, colors, and smells of different flowers attract particular pollinators. In Part One, learners draw and label a flower based on a Pollinator Chart, then build the flower. In Part Two, learners survey others in their class or group to see if they can tell which kinds of pollinator their model flower would attract.

University of Nebraska State Museum

2001-01-01

63

Correlated changes in male plumage coloration and female mate choice in cardueline finches  

E-print Network

Correlated changes in male plumage coloration and female mate choice in cardueline finches GEOFFREY to male ornamental coloration in two species of cardueline finch (the American goldfinch, Carduelis elaborate, ancestral colour pattern. Previous research on another cardueline finch taxon (a subspecies

McGraw, Kevin J.

64

An experimental test of female choice relative to male structural coloration in eastern bluebirds  

Microsoft Academic Search

Several experimental studies have shown that female birds use ornamental melanin and carotenoid plumage coloration as criteria\\u000a in mate choice. Whether females choose mates based on natural variation in structural coloration, however, has not been well\\u000a established. Male eastern bluebirds (Sialia sialis) display brilliant ultraviolet (UV)-blue plumage coloration on their head, back, wings, and tail, which is positively correlated\\u000a with

Mark Liu; Lynn Siefferman; Geoffrey E. Hill

2007-01-01

65

A basic helix-loop-helix transcription factor DvIVS determines flower color intensity in cyanic dahlia cultivars.  

PubMed

The study was aimed to identify the factors that regulate the intensity of flower color in cyanic dahlia (Dahlia variabilis), using fifteen cultivars with different color intensities in their petals. The cultivars were classified into three groups based on their flavonoid composition: ivory white cultivars with flavones; purple and pink cultivars with flavones and anthocyanins; and red cultivars with flavones, anthocyanins, and chalcones. Among the purple, pink, and ivory white cultivars, an inverse relationship was detected between lightness, which was used as an indicator for color intensity and anthocyanin content. A positive correlation was detected between anthocyanin contents and the expression of some structural genes in the anthocyanin synthesis pathway that are regulated by DvIVS, a basic helix-loop-helix transcription factor. A positive correlation between anthocyanin content and expression of DvIVS was also found. The promoter region of DvIVS was classified into three types, with cultivars carrying Type 1 promoter exhibited deep coloring, those carrying Type 2 and/or Type 3 exhibited pale coloring, and those carrying Type 1 and Type 2 and/or Type 3 exhibited medium coloring. The transcripts of the genes from these promoters encoded full-length predicted proteins. These results suggested that the genotype of the promoter region in DvIVS is one of the key factors determining the flower color intensity. PMID:23689377

Ohno, Sho; Deguchi, Ayumi; Hosokawa, Munetaka; Tatsuzawa, Fumi; Doi, Motoaki

2013-08-01

66

Rational choices for the wavelengths of a two color interferometer  

SciTech Connect

If in a two color interferometer for plasma density measurements, the two wavelengths are chosen to have a ratio that is a rational number, and if the signals from each of the wavelengths are multiplied in frequency by the appropriate integer of the rational number and then heterodyned together, the resultant signal will have all effects of component motion nulled out. A phase measurement of this signal will have only plasma density information in it. With CO{sub 2} lasers, it is possible to find suitable wavelength pairs which are close enough to rational numbers to produce an improvement of about 100 in density resolution, compared to standard two color interferometers.

Jobes, F.C.

1995-07-01

67

Molecular analysis of the anthocyanin2 gene of petunia and its role in the evolution of flower color.  

PubMed

The shape and color of flowers are important for plant reproduction because they attract pollinators such as insects and birds. Therefore, it is thought that alterations in these traits may result in the attraction of different pollinators, genetic isolation, and ultimately, (sympatric) speciation. Petunia integrifolia and P. axillaris bear flowers with different shapes and colors that appear to be visited by different insects. The anthocyanin2 (an2) locus, a regulator of the anthocyanin biosynthetic pathway, is the main determinant of color differences. Here, we report an analysis of molecular events at the an2 locus that occur during Petunia spp evolution. We isolated an2 by transposon tagging and found that it encodes a MYB domain protein, indicating that it is a transcription factor. Analysis of P. axillaris subspecies with white flowers showed that they contain an2(-) alleles with two alternative frameshifts at one site, apparently caused by the insertion and subsequent excision of a transposon. A third an2(-) allele has a nonsense mutation elsewhere, indicating that it arose independently. The distribution of polymorphisms in an2(-) alleles suggests that the loss of an2 function and the consequent changes in floral color were not the primary cause for genetic separation of P. integrifolia and P. axillaris. Rather, they were events that occurred late in the speciation process, possibly to reinforce genetic isolation and complete speciation. PMID:10449578

Quattrocchio, F; Wing, J; van der Woude, K; Souer, E; de Vetten, N; Mol, J; Koes, R

1999-08-01

68

So Many Colors, So Many Choices: The Use of Color in Instructional Multimedia Products.  

ERIC Educational Resources Information Center

State-of-the-art computers being used today for instructional multimedia products have monitors capable of displaying millions of different colors. Designers are given virtually unlimited control over the factors that govern the display of these colors. This paper examines how color is displayed on computer monitors and interrelationships with how…

Schaeffer, Randy S.; Bateman, William

69

A Comparative Study on Visual Choice Reaction Time for Different Colors in Females  

PubMed Central

Reaction time is one of the important methods to study a person's central information processing speed and coordinated peripheral movement response. Visual choice reaction time is a type of reaction time and is very important for drivers, pilots, security guards, and so forth. Previous studies were mainly on simple reaction time and there are very few studies on visual choice reaction time. The aim of our study was to compare the visual choice reaction time for red, green, and yellow colors of 60 healthy undergraduate female volunteers. After giving adequate practice, visual choice reaction time was recorded for red, green, and yellow colors using reaction time machine (RTM 608, Medicaid, Chandigarh). Repeated measures of ANOVA and Bonferroni multiple comparison were used for analysis and P < 0.05 was considered statistically significant. The results showed that both red and green had significantly less choice visual choice reaction (P values <0.0001 and 0.0002) when compared with yellow. This could be because individual color mental processing time for yellow color is more than red and green. PMID:25580294

Balakrishnan, Grrishma; Uppinakudru, Gurunandan; Girwar Singh, Gaur; Bangera, Shobith; Dutt Raghavendra, Aswini; Thangavel, Dinesh

2014-01-01

70

Vitamin C, flower color and ploidy variation of hybrids from a ploidy-unbalanced Actinidia interspecific cross and SSR characterization  

Microsoft Academic Search

Seedlings derived from an Actinidia interspecific cross between the hexaploid Actinidia chinensis var. deliciosa ‘Jinkui’ and the diploid male A. eriantha × A. chinensis var. chinensis ‘Chaohong’ hybrid were analyzed using flow cytometry, SSR markers and phenotypic observations. The results show that the\\u000a leaf vitamin C content of this hybrid population has a mid-parent heterosis. Separation of flower color in the progeny

Lei Zhang; Zuozhou Li; Yanchang Wang; Zhengwang Jiang; Shengmei Wang; Hongwen Huang

2010-01-01

71

Male mate choice based upon female nuptial coloration in the brook stickleback, Culaea inconstans (Kirtland)  

Microsoft Academic Search

Female brook sticklebacks develop distinct nuptial coloration following ovulation. When given a choice between a gravid, uncoloured, inter-spawning interval female and a gravid, nuptially coloured female, male brook sticklebacks from two Ontario populations (1) approached the nuptially coloured female first, (2) directed their first courtship pummel towards her, and (3) spent significantly more time with her than with the inter-spawning

DEBORAH A. McLENNAN

1995-01-01

72

Race-Conscious Adoption Choices, Multiraciality, and Color-Blind Racial Ideology  

ERIC Educational Resources Information Center

Analysis of interview data illustrates how White adoptive parents rationalize choices regarding adoptee race. Parents who were willing to adopt children of color stressed unwillingness to adopt Black children. The preference for adopting multiracial children goes against the prevalent method of racial classification, hypodescent, by defining…

Sweeney, Kathryn A.

2013-01-01

73

Effect of salt stress in the regulation of anthocyanins and color of hibiscus flowers by digital image analysis.  

PubMed

The effect of salt stress (200 mM NaCl for 28 days) on physiological characteristics of Hibiscus rosa-sinensis, such as abscisic acid (ABA) content, electrolyte leakage, and photochemical efficiency in leaves, and its influence on biomass production, anthocyanin composition, and color expression of flowers were evaluated. Salinity significantly increased electrolyte leakage and ABA content in leaves and reduced the flower fresh weight. Chlorophyll fluorescence parameters were lower in salt stress condition, compared to control. Moreover, salt stress negatively affected the content of anthocyanins (mainly cyanidin-3-sophoroside), which resulted in a visually perceptible loss of color. The detailed anthocyanin composition monitored by HPLC-DAD-MS and the color variations by digital image analysis due to salt stress showed that the effect was more noticeable at the basal portion of petals. A forward stepwise multiple regression was performed for predicting the content of anthocyanins from appearance characteristics obtained by image analysis, reaching R-square values up to 0.90. PMID:25005605

Trivellini, Alice; Gordillo, Belén; Rodríguez-Pulido, Francisco J; Borghesi, Eva; Ferrante, Antonio; Vernieri, Paolo; Quijada-Morín, Natalia; González-Miret, M Lourdes; Heredia, Francisco J

2014-07-23

74

The Manchester Color Wheel: development of a novel way of identifying color choice and its validation in healthy, anxious and depressed individuals  

Microsoft Academic Search

BACKGROUND: For the purposes of our research programme we needed a simple, reliable and validated method for allowing choice of a color in response to a series of questions. On reviewing the literature no such instrument was available and this study aimed to rectify this situation. This was achieved by developing a simple method of presenting a series of colors

Helen R Carruthers; Julie Morris; Nicholas Tarrier; Peter J Whorwell

2010-01-01

75

REGISTRATION OF A MUTANT LESQUERELLA GENETIC STOCK FOR CREAM FLOWER COLOR  

Technology Transfer Automated Retrieval System (TEKTRAN)

A cream flower mutant of lesquerella [Lesquerella fendleri (A.Gray) S. Watson] genetic stock line WCL-CF1 was released jointly by the Agricultural Research Service, U.S. Department of Agriculture, U.S. Water Conservation Laboratory (USWCL), Phoenix, AZ, and the Universidad Autonoma Agraria Antonio...

76

Apis cerana japonica discriminates between floral color phases of the oriental orchid, Cymbidium floribundum.  

PubMed

Foragers of the Japanese honeybee (Apis cerana japonica) were attracted by flowers of an oriental orchid (Cymbidium floribundum) and were observed to carry the pollinia on their scutella. After the removal of pollinia from the flowers, their labial color changed from white to reddish brown. Both artificial removal of pollinia and ethrel treatment of the flowers also induced this labial color change. Labia in color-changed flowers showed a decreased reflectance of wavelengths less than 670 nm compared to control intact flower. Both reflectance irradiance spectra and ultraviolet photographs showed that only the nectar guide in white (unchanged) flowers reflected ultraviolet light, and that this reflectance decreased with labial color change. Dual choice experiments showed that the honeybee foragers preferentially visited flowers having white labia rather than reddish brown. We suggest that Japanese honeybees discriminate between the floral phases of C. floribundum using color vision. PMID:21110714

Sugahara, Michio; Minamoto, Toshifumi; Fuchikawa, Taro; Michinomae, Masanao; Shimizu, Isamu

2010-12-01

77

Polymorphism and geographic variation of flower color in chilean populations of Eschscholzia californica  

Microsoft Academic Search

In twelve populations ofEschscholzia californica from central Chile, where it was introduced in the latter part of the 19th century, there is a regular gradient in frequency of the allelesJ andj, which control orange vs. yellow flowers, ranging from a maximum value of 0.531 to a minimum of 0.160 forJ. Populations having higher values ofJ occupy more mesic sites. In

R. Godoy; P. Iturra; S. Koref-Santibfifiez; J. Navarro; N. Pacheco; G. L. Stebbins

1975-01-01

78

Genes that determine flower color: the role of regulatory changes in the evolution of phenotypic adaptations  

Microsoft Academic Search

A central goal of evolutionary genetics is to trace the causal pathway between mutations at particular genes and adaptation at the phenotypic level. The proximate objective is to identify adaptations through the analysis of molecular sequence data from specific candidate genes or their regulatory elements. In this paper, we consider the molecular evolution of floral color in the morning glory

Mary L. Durbin; Karen E. Lundy; Peter L. Morrell; Claudia L. Torres-Martinez; Michael T. Clegg

2003-01-01

79

Do Flower Color and Floral Scent of Silene Species affect Host Preference of Hadena bicruris, a Seed-Eating Pollinator, under Field Conditions?  

PubMed Central

Specialization in plant–insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of ?-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds ?-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization. PMID:24905986

Page, Paul; Favre, Adrien; Schiestl, Florian P.; Karrenberg, Sophie

2014-01-01

80

Do flower color and floral scent of silene species affect host preference of Hadena bicruris, a seed-eating pollinator, under field conditions?  

PubMed

Specialization in plant-insect interactions is an important driver of evolutionary divergence; yet, plant traits mediating such interactions are poorly understood. In this study, we investigated how flower color and floral scent are related to seed predation by a seed-eating pollinator. We used field-transplanted recombinant F2 hybrids between Silene latifolia and S. dioica that are the preferred and alternative hosts of the moth Hadena bicruris and crosses within these species for comparison. We scored seed predation and flower color and analyzed floral scent. Pinker S. dioica-like flowers and emission of ?-pinene decreased the odds of seed predation while emission of benzyl acetate and 6-methyl-5-hepten-2-one increased the odds of seed predation. Emission of these compounds did not differ significantly between the two Silene species. Our results suggest that flower color plays an important role in the specific interaction of H. bicruris with its preferred host S. latifolia. The compounds ?-pinene, benzyl acetate and 6-methyl-5-hepten-2-one could represent non-specific deterrents and attractants to ovipositing moths. Alternatively, emission of these compounds could be related to herbivory or pathogen attack and act as a signal for host quality. This would weaken the predictability of the plant's costs and benefits of the interaction and act to maintain an imperfect degree of specialization. PMID:24905986

Page, Paul; Favre, Adrien; Schiestl, Florian P; Karrenberg, Sophie

2014-01-01

81

Sexual Dimorphism of Staminate- and Pistillate-Phase Flowers of Saponaria officinalis (Bouncing Bet) Affects Pollinator Behavior and Seed Set  

PubMed Central

The sequential separation of male and female function in flowers of dichogamous species allows for the evolution of differing morphologies that maximize fitness through seed siring and seed set. We examined staminate- and pistillate-phase flowers of protandrous Saponaria officinalis for dimorphism in floral traits and their effects on pollinator attraction and seed set. Pistillate-phase flowers have larger petals, greater mass, and are pinker in color, but due to a shape change, pistillate-phase flowers have smaller corolla diameters than staminate-phase flowers. There was no difference in nectar volume or sugar content one day after anthesis, and minimal evidence for UV nectar guide patterns in staminate- and pistillate-phase flowers. When presented with choice arrays, pollinators discriminated against pistillate-phase flowers based on their pink color. Finally, in an experimental garden, in 2012 there was a negative correlation between seed set of an open-pollinated, emasculated flower and pinkness (as measured by reflectance spectrometry) of a pistillate-phase flower on the same plant in plots covered with shade cloth. In 2013, clones of genotypes chosen from the 2012 plants that produced pinker flowers had lower seed set than those from genotypes with paler flowers. Lower seed set of pink genotypes was found in open-pollinated and hand-pollinated flowers, indicating the lower seed set might be due to other differences between pink and pale genotypes in addition to pollinator discrimination against pink flowers. In conclusion, staminate- and pistillate-phase flowers of S. officinalis are dimorphic in shape and color. Pollinators discriminate among flowers based on these differences, and individuals whose pistillate-phase flowers are most different in color from their staminate-phase flowers make fewer seeds. We suggest morphological studies of the two sex phases in dichogamous, hermaphroditic species can contribute to understanding the evolution of sexual dimorphism in plants without the confounding effects of genetic differences between separate male and female individuals. PMID:24690875

Davis, Sandra L.; Dudle, Dana A.; Nawrocki, Jenna R.; Freestone, Leah M.; Konieczny, Peter; Tobin, Michael B.; Britton, Michael M.

2014-01-01

82

The effect of male coloration on female mate choice in closely related Lake Victoria cichlids ( Haplochromis nyererei complex)  

Microsoft Academic Search

We studied the effect of male coloration on interspecific female mate choice in two closely related species of haplochromine\\u000a cichlids from Lake Victoria. The species differ primarily in male coloration. Males of one species are red, those of the other\\u000a are blue. We recorded the behavioral responses of females to males of both species in paired male trials under white

Ole Seehausen; Jacques J. M. van Alphen

1998-01-01

83

Genetic divergence causes parallel evolution of flower color in Chilean Mimulus.  

PubMed

Deciphering the genetic architecture of phenotypic change provides a framework for understanding how evolution proceeds at a genetic level, and paves the way for work at the molecular level. A series of intra- and interspecific crosses were used to investigate the genetic control of recently evolved floral pigmentation phenotypes in a group of closely related Mimulus species from central Chile. An intraspecific polymorphism was found to be controlled by a single Mendelian locus. Differences between species, by contrast, were composed of multiple independent patterning elements, including both Mendelian and polygenic traits. The most striking phenotypic novelty in this group, anthocyanin pigmentation in the petal lobes, has evolved three times independently. The results illustrate how genetically simple modular elements can interact with polygenic or quantitative traits to create complex new phenotypes. The repeated evolution of petal lobe anthocyanins suggests that natural selection may have played a role in the evolution of red coloration in the Chilean Mimulus, and shows that red coloration has been achieved via different genetic pathways in these closely related species. PMID:19453433

Cooley, Arielle M; Willis, John H

2009-08-01

84

Local adaptation and matching habitat choice in female barn owls with respect to melanic coloration.  

PubMed

Local adaptation is a major mechanism underlying the maintenance of phenotypic variation in spatially heterogeneous environments. In the barn owl (Tyto alba), dark and pale reddish-pheomelanic individuals are adapted to conditions prevailing in northern and southern Europe, respectively. Using a long-term dataset from Central Europe, we report results consistent with the hypothesis that the different pheomelanic phenotypes are adapted to specific local conditions in females, but not in males. Compared to whitish females, reddish females bred in sites surrounded by more arable fields and less forests. Colour-dependent habitat choice was apparently beneficial. First, whitish females produced more fledglings when breeding in wooded areas, whereas reddish females when breeding in sites with more arable fields. Second, cross-fostering experiments showed that female nestlings grew wings more rapidly when both their foster and biological mothers were of similar colour. The latter result suggests that mothers should particularly produce daughters in environments that best match their own coloration. Accordingly, whiter females produced fewer daughters in territories with more arable fields. In conclusion, females displaying alternative melanic phenotypes bred in habitats providing them with the highest fitness benefits. Although small in magnitude, matching habitat selection and local adaptation may help maintain variation in pheomelanin coloration in the barn owl. PMID:22070193

Dreiss, A N; Antoniazza, S; Burri, R; Fumagalli, L; Sonnay, C; Frey, C; Goudet, J; Roulin, Alexandre

2012-01-01

85

Color  

NSDL National Science Digital Library

Using this project will expose you to concepts of color, color wheels, color combinations, and techniques of using color. Use the following links, follow the directions to define color terms, create color schemes and explore the use of color in creating designs. Color Scheme Generator 2 This site identifiesbasic terms related to color, using acolor wheeland making color schemes. Color Theory This site explains terminology of color. Color Theory Tutorial This site gives excellent examples and information about ...

Mrs. Dent

2010-03-23

86

Synchrony between flower opening and petal-color change from red to blue in morning glory, Ipomoea tricolor cv. Heavenly Blue.  

PubMed

Petal color change in morning glory Ipomoea tricolor cv. Heavenly Blue, from red to blue, during the flower-opening period is due to an unusual increase in vacuolar pH (pHv) from 6.6 to 7.7 in colored epidermal cells. We clarified that this pHv increase is involved in tonoplast-localized Na+/H+ exchanger (NHX). However, the mechanism of pHv increase and the physiological role of NHX1 in petal cells have remained obscure. In this study, synchrony of petal-color change from red to blue, pHv increase, K+ accumulation, and cell expansion growth during flower-opening period were examined with special reference to ItNHX1. We concluded that ItNHX1 exchanges K+, but not Na+, with H+ to accumulate an ionic osmoticum in the vacuole, which is then followed by cell expansion growth. This function may lead to full opening of petals with a characteristic blue color. PMID:19521056

Yoshida, Kumi; Miki, Naoko; Momonoi, Kazumi; Kawachi, Miki; Katou, Kiyoshi; Okazaki, Yoshiji; Uozumi, Nobuyuki; Maeshima, Masayoshi; Kondo, Tadao

2009-01-01

87

Synchrony between flower opening and petal-color change from red to blue in morning glory, Ipomoea tricolor cv. Heavenly Blue  

PubMed Central

Petal color change in morning glory Ipomoea tricolor cv. Heavenly Blue, from red to blue, during the flower-opening period is due to an unusual increase in vacuolar pH (pHv) from 6.6 to 7.7 in colored epidermal cells. We clarified that this pHv increase is involved in tonoplast-localized Na+/H+ exchanger (NHX). However, the mechanism of pHv increase and the physiological role of NHX1 in petal cells have remained obscure. In this study, synchrony of petal-color change from red to blue, pHv increase, K+ accumulation, and cell expansion growth during flower-opening period were examined with special reference to ItNHX1. We concluded that ItNHX1 exchanges K+, but not Na+, with H+ to accumulate an ionic osmoticum in the vacuole, which is then followed by cell expansion growth. This function may lead to full opening of petals with a characteristic blue color. PMID:19521056

Yoshida, Kumi; Miki, Naoko; Momonoi, Kazumi; Kawachi, Miki; Katou, Kiyoshi; Okazaki, Yoshiji; Uozumi, Nobuyuki; Maeshima, Masayoshi; Kondo, Tadao

2009-01-01

88

Alternative expression of vacuolar iron transporter and ferritin genes leads to blue/purple coloration of flowers in tulip cv. 'Murasakizuisho'.  

PubMed

Flowers of tulip cv. 'Murasakizuisho' have a purple perianth except for the bottom region, which is blue in color even though it has the same anthocyanin, delphinidin 3-O-rutinoside, as the entire perianth. The development of the blue coloration in the perianth bottom is due to complexation by anthocyanin, flavonol and iron (Fe), as well as a vacuolar iron transporter, TgVit1. Although transient expression of TgVit1 in the purple cells led to a color change to light blue, the coloration of the transformed cells did not coincide with the dark blue color of the cells of the perianth bottom. We thought that another factor is required for the blue coloration of the cells of perianth bottom. To examine the effect of ferritin (FER), an Fe storage protein, on blue color development, we cloned an FER gene (TgFER1) and performed expression analyses. TgFER1 transcripts were found in the cells located in the upper region of the petals along with purple color development by anthocyanin and were not found in the blue cells of the perianth bottom. This gene expression is in contrast to that of TgVit1, expressed only in the cells of the perianth bottom. Co-expression of TgVIT1 and TgFER-RNAi, constructed for suppressing endogenous TgFER1 by RNA interference (RNAi), changed the purple petal cells to a dark blue color similar to that of the natural perianth bottom. These results strongly suggest that TgVit1 expression and TgFER1 suppression are critical for the development of blue color in the perianth bottom. PMID:20022978

Shoji, Kazuaki; Momonoi, Kazumi; Tsuji, Tosiaki

2010-02-01

89

Color  

NSDL National Science Digital Library

This project will be used to teach the importance of color. Watch the following video about color Primary Colors Click on the link Exploration of Color. When you get into the website select the different colors to see what secondary colors are made from the primary colors. Review the following siteColor Theory and then design and paint a color wheel. ...

JoLene

2008-09-29

90

Flowers, Beautiful Flowers  

ERIC Educational Resources Information Center

In the lesson described, the middle school students had been studying the artist Georgia O'Keeffe and the history of her work. Students enhanced their flower portraits by adding a matching border and connecting the lesson to other subject areas. Students dissected a flower and drew a small diagram of the flower and labeled the parts. This is an…

School Arts: The Art Education Magazine for Teachers, 2005

2005-01-01

91

Design a Flower  

NSDL National Science Digital Library

In this activity, learners learn about the adaptations that flowers have developed which support pollination. Learners also list their personal preferences (i.e. favorite color, food) and a partner will create a "designer flower" to match their preferences. Learners can participate in a Take-Home challenge, in which they will draw a fictional pollinator-plant pair.

Lydia Pollack

2010-01-01

92

Flower color chimera and abnormal leaf mutants induced by 12C 6+ heavy ions in Salvia splendens Ker-Gawl  

Microsoft Academic Search

The effect of 12C6+ heavy ions bombardment on mutagenesis in Salvia splendens Ker-Gawl. was studied. Dose–response studies indicated that there was a peak of malformation frequency of S. splendens at 200Gy. Abnormal leaf mutants of the bileaf, trileaf and tetraleaf conglutination were selected. Meanwhile, a bicolor flower chimera with dark red and fresh red flower was isolated in M1 generation

D. L. Wu; S. W. Hou; P. P. Qian; L. D. Sun; Y. C. Zhang; W. J. Li

2009-01-01

93

Glowing Flowers  

NSDL National Science Digital Library

Student teams learn about engineering design of green fluorescent proteins (GFPs) and their use in medical research, including stem cell research. They simulate the use of GFPs by adding fluorescent dye to water and letting a flower or plant to transport the dye throughout its structure. Students apply their knowledge of GFPs to engineering applications in the medical, environmental and space exploration fields. Due to the fluorescing nature of the dye, plant life of any color, light or dark, can be used — unlike dyes that can only be seen in visible light.

Integrated Teaching and Learning Program,

94

FEMALE MATE CHOICE IN RELATION TO STRUCTURAL PLUMAGE COLORATION IN BLUE GROSBEAKS  

Microsoft Academic Search

Plumage blueness in Blue Grosbeaks (Passerina caerulea) is related to nutritional condition during molt, and bluer males hold larger territories with more food resources. We tested the hypothesis that females use male plumage brightness as a criterion in choosing mates. In a mate-choice aviary, we pre- sented females with a choice between males whose feathers were either brightened with blue

Barbara Ballentine; Geoffrey E. Hill

2003-01-01

95

The involvement of tonoplast proton pumps and Na+(K+)/H+ exchangers in the change of petal color during flower opening of Morning Glory, Ipomoea tricolor cv. Heavenly Blue.  

PubMed

The petal color of morning glory, Ipomoea tricolor cv. Heavenly Blue, changes from purplish red to blue during flower opening. This color change is caused by an unusual increase in vacuolar pH from 6.6 to 7.7 in the colored adaxial and abaxial cells. To clarify the mechanism underlying the alkalization of epidermal vacuoles in the open petals, we focused on vacuolar H+-ATPase (V-ATPase), H+-pyrophosphatase (V-PPase) and an isoform of Na+/H+ exchanger (NHX1). We isolated red and blue protoplasts from the petals in bud and fully open flower, respectively, and purified vacuolar membranes. The membranes contained V-ATPase, V-PPase and NHX1, which were immunochemically detected, with relatively high transport activity. NHX1 could be detected only in the vacuolar membranes prepared from flower petals and its protein level was the highest in the colored petal epidermis of the open flower. These results suggest that the increase of vacuolar pH in the petals during flower opening is due to active transport of Na+ and/or K+ from the cytosol into vacuoles through a sodium- or potassium-driven Na+(K+)/H+ exchanger NXH1 and that V-PPase and V-ATPase may prevent the over-alkalization. This systematic ion transport maintains the weakly alkaline vacuolar pH, producing the sky-blue petals. PMID:15695444

Yoshida, Kumi; Kawachi, Miki; Mori, Mihoko; Maeshima, Masayoshi; Kondo, Maki; Nishimura, Mikio; Kondo, Tadao

2005-03-01

96

Colored and White Sectors from Star-Patterned Petunia Flowers Display Differential Resistance to Corn Earworm and Cabbage Looper Larvae  

Technology Transfer Automated Retrieval System (TEKTRAN)

Anthocyanins are likely a visual aid for attracting pollinators. However, there is also the possibility that anthocyanins are present in some flowers as defensive molecules protecting them from excess light, pathogens or herbivores. In this study, resistance due to anthocyanins from commercial pet...

97

Flower Face Face Face Face Flower Tree Tree Tree Tree  

E-print Network

Flower Flower Flower Flower Flower Face Face Face Face Flower Flower Tree Tree Tree Tree Flower Flower Flower Flower Sky Sky Sky Sky Flower Grass Grass Grass Grass Flower Flower Flower #12;Sign Sign Road Road Chair Face Face Face Face Chair #12;Chair Chair Chair Flower Flower Flower Flower Grass Chair

Chen, Tsuhan

98

Hibiscus flower  

NSDL National Science Digital Library

The flower is the reproductive structure of the angiosperms. Many angiosperms need insects to transfer pollen from one flower to the stigma of another. After fertilization, the ovules inside the flower develop into seeds. Enclosed seeds distinguish angiosperms from gymnosperms.

Katie Hale (California State University, Fullerton; Student, Biological Sciences)

2007-01-13

99

Female nuptial coloration and its adaptive significance in a mutual mate choice system  

Microsoft Academic Search

Adaptive female coloration is likely to occur when males largely invest into reproduction or variance of quality between potential mating partners is high. Although recent studies have shown male choosiness of female traits, little is known about the extent to which female ornamentation signals benefits to males. Female ornamentation might signal individual quality information and thus might be sexually selected

Sebastian A. Baldauf; Theo C. M. Bakker; Harald Kullmann; Timo Thünken

2011-01-01

100

Color-Changing Carnations  

NSDL National Science Digital Library

Learners place cut flowers in colored water and observe how the flowers change. The flowers absorb the water through the stem and leaves. By watching the journey of harmless food coloring, learners can see all the places water goes in a plant.

Museum of Science and Industry, Chicago

2012-01-01

101

'Le Rouge et le Noir': A decline in flavone formation correlates with the rare color of black dahlia (Dahlia variabilis hort.) flowers  

PubMed Central

Background More than 20,000 cultivars of garden dahlia (Dahlia variabilis hort.) are available showing flower colour from white, yellow and orange to every imaginable hue of red and purple tones. Thereof, only a handful of cultivars are so-called black dahlias showing distinct black-red tints. Flower colour in dahlia is a result of the accumulation of red anthocyanins, yellow anthochlors (6’-deoxychalcones and 4-deoxyaurones) and colourless flavones and flavonols, which act as copigments. White and yellow coloration occurs only if the pathway leading to anthocyanins is incomplete. Not in all cultivars the same step of the anthocyanin pathway is affected, but the lack of dihydroflavonol 4-reductase activity is frequently observed and this seems to be based on the suppression of the transcription factor DvIVS. The hitherto unknown molecular background for black colour in dahlia is here presented. Results Black cultivars accumulate high amounts of anthocyanins, but show drastically reduced flavone contents. High activities were observed for all enzymes from the anthocyanin pathway whereas FNS II activity could not be detected or only to a low extent in 13 of 14 cultivars. cDNA clones and genomic clones of FNS II were isolated. Independently from the colour type, heterologous expression of the cDNA clones resulted in functionally active enzymes. FNS II possesses one intron of varying length. Quantitative Real-time PCR showed that FNS II expression in black cultivars is low compared to other cultivars. No differences between black and red cultivars were observed in the expression of transcription factors IVS and possible regulatory genes WDR1, WDR2, MYB1, MYB2, 3RMYB and DEL or the structural genes of the flavonoid pathway. Despite the suppression of FHT expression, flavanone 3-hydroxylase (FHT, synonym F3H) enzyme activity was clearly present in the yellow and white cultivars. Conclusions An increased accumulation of anthocyanins establishes the black flowering phenotypes. In the majority of black cultivars this is due to decreased flavone accumulation and thus a lack of competition for flavanones as the common precursors of flavone formation and the anthocyanin pathway. The low FNS II activity is reflected by decreased FNS II expression. PMID:23176321

2012-01-01

102

Discovering Flowers in a New Light  

NSDL National Science Digital Library

Although students may have made observations of plants and flowers, not many have looked closely at their various structures or seen the colorful designs of flowers that are only apparent when magnified. The 5E learning cycle described in this article engages students in scientific inquiry using digital microscopy to explore the various parts of a flower.

Randy L. Bell

2004-01-01

103

COLORS!  

NSDL National Science Digital Library

In this project, students will learn about primary, secondary, and complementary colors. After exploring a few sites and participating in a few deep questions as a class, they will create an optical illusion using complimentary colors. Younger students who are learning this unit will need to do this activity with a parent or as a class with a teacher or aide. INTRODUCTION: Questions to discuss with the students: 1. What colors do you see in this room? 2. What are some jobs that use colors? An Artist? Decorator? ...

Sarah

2009-09-28

104

Blob Flowers.  

ERIC Educational Resources Information Center

Describes an art project called blob flowers in which fifth-grade students created pictures of flowers using watercolor and markers. Explains that the lesson incorporates ideas from art and science. Discusses in detail how the students created their flowers. (CMK)

Canfield, Elaine

2003-01-01

105

Quantitative Genetic Analyses of Male Color Pattern and Female Mate Choice in a Pair of Cichlid Fishes of Lake Malawi, East Africa  

PubMed Central

The traits involved in sexual selection, such as male secondary sexual characteristics and female mate choice, often co-evolve which can promote population differentiation. However, the genetic architecture of these phenotypes can influence their evolvability and thereby affect the divergence of species. The extraordinary diversity of East African cichlid fishes is often attributed to strong sexual selection and thus this system provides an excellent model to test predictions regarding the genetic architecture of sexually selected traits that contribute to reproductive isolation. In particular, theory predicts that rapid speciation is facilitated when male sexual traits and female mating preferences are controlled by a limited number of linked genes. However, few studies have examined the genetic basis of male secondary sexual traits and female mating preferences in cichlids and none have investigated the genetic architecture of both jointly. In this study, we artificially hybridized a pair of behaviorally isolated cichlid fishes from Lake Malawi and quantified both melanistic color pattern and female mate choice. We investigated the genetic architecture of both phenotypes using quantitative genetic analyses. Our results suggest that 1) many non-additively acting genetic factors influence melanistic color patterns, 2) female mate choice may be controlled by a minimum of 1–2 non-additive genetic factors, and 3) F2 female mate choice is not influenced by male courting effort. Furthermore, a joint analysis of color pattern and female mate choice indicates that the genes underlying these two traits are unlikely to be physically linked. These results suggest that reproductive isolation may evolve rapidly owing to the few genetic factors underlying female mate choice. Hence, female mate choice likely played an important role in the unparalleled speciation of East African cichlid fish. PMID:25494046

Ding, Baoqing; Daugherty, Daniel W.; Husemann, Martin; Chen, Ming; Howe, Aimee E.; Danley, Patrick D.

2014-01-01

106

Flower Powder  

NSDL National Science Digital Library

In this outdoor activity, learners use artificial bees and paper models of flowers to find out how bees transfer pollen from one flower to another. Background information discusses bees and other pollinators such as hummingbirds and butterflies, and describes the way bees move pollen around. Learners use pollen boards to pick up pollen from real flowers, make paper flowers to learn how real flowers are structured, use model flowers and artificial bees to act out bees visiting flowers for pollen, and use artificial bees to collect real pollen. Learners are asked to consider other kinds of pollination (wind, water or larger animals) and the impact on pollination when bees are killed with insect poison.

2012-06-26

107

Composite Flowers  

NSDL National Science Digital Library

This site, part of Jim Conrad's Backyard Nature Plant web page, discusses this very large family of plants, which includes the sunflower, dandelion, and chrysanthemum. Here you will find information about the composite family's flower structure and the three kinds of composite flowers: ray only, disk only, and ray and disk. There is also a section on how to analyze disk and ray flower structures.

Conrad, Jim

108

Flower Development  

PubMed Central

Flowers are the most complex structures of plants. Studies of Arabidopsis thaliana, which has typical eudicot flowers, have been fundamental in advancing the structural and molecular understanding of flower development. The main processes and stages of Arabidopsis flower development are summarized to provide a framework in which to interpret the detailed molecular genetic studies of genes assigned functions during flower development and is extended to recent genomics studies uncovering the key regulatory modules involved. Computational models have been used to study the concerted action and dynamics of the gene regulatory module that underlies patterning of the Arabidopsis inflorescence meristem and specification of the primordial cell types during early stages of flower development. This includes the gene combinations that specify sepal, petal, stamen and carpel identity, and genes that interact with them. As a dynamic gene regulatory network this module has been shown to converge to stable multigenic profiles that depend upon the overall network topology and are thus robust, which can explain the canalization of flower organ determination and the overall conservation of the basic flower plan among eudicots. Comparative and evolutionary approaches derived from Arabidopsis studies pave the way to studying the molecular basis of diverse floral morphologies. PMID:22303253

Alvarez-Buylla, Elena R.; Benítez, Mariana; Corvera-Poiré, Adriana; Chaos Cador, Álvaro; de Folter, Stefan; Gamboa de Buen, Alicia; Garay-Arroyo, Adriana; García-Ponce, Berenice; Jaimes-Miranda, Fabiola; Pérez-Ruiz, Rigoberto V.; Pińeyro-Nelson, Alma; Sánchez-Corrales, Yara E.

2010-01-01

109

An intragenic tandem duplication in a transcriptional regulatory gene for anthocyanin biosynthesis confers pale-colored flowers and seeds with fine spots in Ipomoea tricolor.  

PubMed

While the wild-type morning glory (Ipomoea tricolor) displays bright-blue flowers and dark-brown seeds, its spontaneous mutant, Blue Star, carrying the mutable ivory seed-variegated (ivs-v) allele, exhibits pale-blue flowers with a few fine blue spots and ivory seeds with tiny dark-brown spots. The mutable allele is caused by an intragenic tandem duplication of 3.3 kbp within a gene for transcriptional activator containing a basic helix-loop-helix (bHLH) DNA-binding motif. Each of the tandem repeats is flanked by a 3-bp sequence AAT, indicating that the 3-bp microhomology is used to generate the tandem duplication. The transcripts in the pale-blue flower buds of the mutant contain an internal 583-bp tandem duplication that results in the production of a truncated polypeptide lacking the bHLH domain. The mRNA accumulation of most of the structural genes encoding enzymes for anthocyanin biosynthesis in the flower buds of the mutant was significantly reduced. The transcripts identical to the wild-type mRNAs for the transcriptional activator were present abundantly in blue spots of the variegated flowers, whereas the transcripts containing the 583-bp tandem duplication were predominant in the pale-blue background of the same flowers. The flower and seed variegations studied here are likely to be caused by somatic homologous recombination between an intragenic tandem duplication in the gene encoding a bHLH transcriptional activator for anthocyanin biosynthesis, whereas various flower variegations are reported to be caused by excision of DNA transposons inserted into pigmentation genes. PMID:15144384

Park, Kyeung-Il; Choi, Jeong-Doo; Hoshino, Atsushi; Morita, Yasumasa; Iida, Shigeru

2004-06-01

110

Colorful Collage: Visions of Flowers  

ERIC Educational Resources Information Center

The technique of what people today call "collage" is not new. In Victorian times, elaborate art was created from bristly horsehair as a type of collage. The modern collage dates to the early 1900s when Picasso pasted newspaper on a drawing. In 1919 Karl Schwitters, a German artist, developed collage into an art form that was as important as…

Skophammer, Karen

2011-01-01

111

A Comprehensive Evaluation of Yellow-flowering Magnolias  

Technology Transfer Automated Retrieval System (TEKTRAN)

A collection of yellow-flowering magnolias were evaluated for flower color, bloom duration and growth rate in USDA Hardiness Zone 6b. All selections were reported to have yellow blooms; however, tepal color in this test ranged from light pink with some yellow coloration to dark yellow. The darkest...

112

Minority mating advantage of certain eye color mutants of Drosophila melanogaster . I. Multiple-choice and single-female tests  

Microsoft Academic Search

Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (10?10 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority

Eliot B. Spiess; William A. Schwer

1978-01-01

113

Flowers & Weeds.  

ERIC Educational Resources Information Center

Describes the topics and teaching strategies employed in an Issues in Biology course. Discusses flowers, plant breeding, potatoes and tomatoes, the chocolate tree, weeds, Arabidopis, gene transfers, and plant genes/human genes. Contains 22 references. (JRH)

Flannery, Maura C.

1996-01-01

114

The regulation of carotenoid pigmentation in flowers  

Microsoft Academic Search

Carotenoids fulfill many processes that are essential for normal growth and development in plants, but they are also responsible for the breathtaking variety of red-to-yellow colors we see in flowers and fruits. Although such visual diversity helps to attract pollinators and encourages herbivores to distribute seeds, humans also benefit from the aesthetic properties of flowers and an entire floriculture industry

Changfu Zhu; Chao Bai; Georgina Sanahuja; Dawei Yuan; Gemma Farré; Shaista Naqvi; Lianxuan Shi; Teresa Capell; Paul Christou

2010-01-01

115

College Major Choice for Students of Color: Toward a Model of Recruitment for the Agricultural Education Profession  

ERIC Educational Resources Information Center

The purpose of this study was to gain a deeper understanding of the reasons students, identifying as non-White, made the decision to pursue a career in agricultural education. This phenomenological study allowed the researchers to obtain the overall phenomenon of the thought processes that encompass decisions of students of color when selecting an…

Vincent, Stacy K.; Henry, Anna L.; Anderson, James C., II

2012-01-01

116

[Literature study on species of honeysuckle flower].  

PubMed

Honeysuckle flower is a traditional herbal medicine in China Through systemically sorting and studying literature of Chinese medicine, this article pointed out that leech used by the traditional Chinese medicine in ancient time has the features of twist vine, slight purple stem with clothing hair; opposite growing leaves, ovule shape with clothing hair on both side; two flowers growing from one pedicel, labiate corolla with 3.2 cm longth, flower grows from white color to yellow color, each branch axil grows only one pedicel, the involucre is ovoid shape, and the flower season is from mid-March to mid-May. Among all species of caprifoliaceae, only Lonicera japonica Thunb. meets these botanic features. Therefore, L. japonica Thunb. should be used as the orthodox species of herbal honeysuckle flower. PMID:25244752

Zhang, Wei; Huang, Lu-Qi; Li, Chao-Xia; Li, Jian; Zhang, Rui-Xian

2014-06-01

117

Flowering and expression of flowering-related genes under long-day conditions with light-emitting diodes  

Microsoft Academic Search

The effects of light quality on flowering time were investigated in Gypsophila paniculata, which is a long-day cut flower, and with Arabidopsis under long-day conditions with light-emitting diodes (LEDs). Gypsophila paniculata plants were grown under natural daylight and flowering was controlled by long-day treatment with a weak LED light of a single\\u000a color in the night. Flowering was promoted not

Yoshimi Hori; Koji Nishidate; Manabu Nishiyama; Koki Kanahama; Yoshinori Kanayama

118

Tiny Multiple Choice Test Consider the following example XML tree in which the current node is colored black  

E-print Network

the current node is colored black: a g h b c i j k d e f l m n Question 1 Which nodes belong to the descendant axis for the current node in the above example XML tree? a d,e,f b c,e,f c b,c,d,e,f d a,b,c,d,e,f,c,i,j,k b a c b,c,d,e,f d b,c Question 3 Which nodes belong to the preceding axis for the current node

Schwartzbach, Michael I.

119

Indexing Flower Patent Images using Domain Knowledge Madirakshi Das R. Manmatha Edward M. Riseman  

E-print Network

Indexing Flower Patent Images using Domain Knowledge Madirakshi Das R. Manmatha Edward M. Riseman a solution to the problem of indexing images of flowers for searching a flower patents database by color. The flower region is isolated from the background by using an automatic iterative segmentation algorithm

Massachusetts at Amherst, University of

120

Colors, Colors?  

NSDL National Science Digital Library

In this activity related to the famous "Stroop Effect," learners explore how words influence what we see and how the brain handles "mixed messages." Learners read colored words and are asked to say the color of the word, not what the word says. Learners use a data table to keep track of where they have trouble reading the colors. They analyze this data by answering questions and drawing conclusions. Learners can also take this test using the online version.

Susan Songstad

2009-01-01

121

Flowers in Their Variety.  

ERIC Educational Resources Information Center

Describes the diversity of flowers with regard to the flower paintings of Pierre-Joseph Redoute, books about flowers, and research in genetic studies. Discusses gardening flowers and flowering strategies and criticizes the fact that biology education has moved steadily away from plants. (KHR)

Flannery, Maura C.

2002-01-01

122

Inheritance of flower, stem, leaf, and disease traits in three diploid interspecific rose populations  

E-print Network

interspecific backcross populations to observe the segregation of several morphological and disease resistance traits. The qualitative traits of bloom habit, flower color, flower form, and presence of stem prickles were characterized in two locations in College...

Shupert, David Andrew

2006-10-30

123

77 FR 12103 - Culturally Significant Objects Imported for Exhibition Determinations: “Colorful Realm: Japanese...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Determinations: ``Colorful Realm: Japanese Bird-and-Flower Paintings by It[omacr] Jakuch[umacr] (1716-1800...in the exhibition ``Colorful Realm: Japanese Bird-and-Flower Paintings by It[omacr] Jakuch[umacr]...

2012-02-28

124

Behavioral Ecology Vol. 9 No. 3: 215-219 Flower constancy in the hoverflies Episyrphus  

E-print Network

when visiting flowers in seminatural plant communities and in artificial arrays of two color morphs foraging among polymorphic flowers, which all describe positive frequency-dependent selection. Possible exBehavioral Ecology Vol. 9 No. 3: 215-219 Flower constancy in the hoverflies Episyrphus balteatus

125

Discovering Flowers in a New Light  

ERIC Educational Resources Information Center

Children love observing seeds change as they germinate and grow into tall healthy plants, but how can teachers make investigating plants an exciting and immediate event? Microscopy might just be the answer. Although most students have seen flowers, not many have looked closely at their various structures or seen their colorful designs only…

McNall, Rebecca L.; Bell, Randy L.

2004-01-01

126

Is flower selection influenced by chemical imprinting to larval food provisions in the generalist bee Osmia  

E-print Network

Is flower selection influenced by chemical imprinting to larval food provisions in the generalist ­ Revised 30 April 2012 ­ Accepted 9 May 2012 Abstract ­ To investigate whether flower selection). Flower preferences by adults were evaluated in multiple-choice behavioral tests based on visit number

127

Flower Power Against Crime  

E-print Network

Broadcast Transcript: From the "Beautification Bashes Burglary" File comes this: Residents of a neighborhood here in Tokyo are planting flowers to stamp out crime. When a neighborhood watch group reported that streets with flowers had fewer...

Hacker, Randi

2009-08-26

128

Regulation of skin color in apples  

Microsoft Academic Search

The literature of the regulation of color in apple skin is reviewed and compared with current knowledge of the regulation of flower color.Color in apple skin is a blend of various amounts of chlorophyll, carotenoids, and anthocyanins\\/flavonols. A variety of red colors are produced by cyanidin glycosides copigmented with flavonols and other compounds. The concentration and identification of flavonols, proanthocyanidins,

J. E. Lancaster; Donald K. Dougall

1992-01-01

129

Bee on flower  

NSDL National Science Digital Library

Bees visit flowering plants to collect nectar so they can store it as honey back at their hives. As a bee visits one flower after another, pollen collects on its entire body and especially on the legs. Bees help pollinate flowers while they collect nectar. This is a mutualistic behavior.

N/A N/A (None; )

2006-07-15

130

Design a Hummingbird Flower.  

ERIC Educational Resources Information Center

Presents an activity that engages students in designing and making an artificial flower adapted for pollination by hummingbirds. Students work in teams to design flowers that maximize the benefit from attracting hummingbirds. Examines characteristics of real flowers adapted to pollination by hummingbirds. (DLH)

Bailey, Kim

2002-01-01

131

Flower Dissection Lab  

NSDL National Science Digital Library

From Fairchild Tropical Botanic Garden, this site presents a simple Flower Dissection Lab using orchids and composite flowers. This pdf document contains the materials needed and instructions for the lab, as well as a worksheet for students to complete as they dissect their flower.

132

Sepal phenolic profile during Helleborus niger flower development.  

PubMed

Morphological changes and phenolic patterns of developing hellebore sepals and the effects of pistil removal on these parameters were studied by comparing six flower stages of Helleborus niger. Color changes were evaluated colorimetrically, chlorophyll content was measured spectrophotometrically, and anthocyanins and flavonols were identified and quantified with HPLC-MS. Pistil removal not only altered the morphological development of hellebore flower resulting in smaller flower and significant color changes but also lead to several biochemical modifications. Five cyanidin glycosides have been identified from the group of anthocyanins in hellebore. Individual and total anthocyanin content increased from bud to subsequent developmental stages. Moreover, significantly higher content levels of individual and total anthocyanins have been measured in non-pollinated flower sepals compared to sepals of pollinated flowers. From the group of flavonols eight quercetin and kaempferol compounds have been quantified in hellebore sepals. Flavonol content significantly decreased during flower development with lowest levels recorded in sepals of non-pollinated and senescent pollinated hellebore flowers. Sepals of pollinated flowers contained highest levels of chlorophyll and significantly lower amounts of chlorophyll were measured in non-pollinated flowers and in sepals of senescent stage. PMID:23796521

Schmitzer, Valentina; Mikulic-Petkovsek, Maja; Stampar, Franci

2013-11-01

133

Genetic and Linkage Analysis of Purple-blue Flower in Soybean  

Microsoft Academic Search

Flower color of soybean is primarily controlled by genes W1, W3, W4, Wm, and Wp. In addition, the soybean gene symbol W2, w2 produces purple-blue flower in combination with W1. This study was conducted to determine the genetic control of purple-blue flower of cultivar (cv). Nezumisaya. F1 plants derived from a cross between Nezumisaya and purple flower cv. Harosoy had

RYOJI TAKAHASHI; H. Matsumura; M. E. Oyoo; N. A. Khan

2008-01-01

134

Yellow flowers generated by expression of the aurone biosynthetic pathway  

PubMed Central

Flower color is most often conferred by colored flavonoid pigments. Aurone flavonoids confer a bright yellow color on flowers such as snapdragon (Antirrhinum majus) and dahlia (Dahlia variabilis). A. majus aureusidin synthase (AmAS1) was identified as the key enzyme that catalyzes aurone biosynthesis from chalcones, but transgenic flowers overexpressing AmAS1 gene failed to produce aurones. Here, we report that chalcone 4?-O-glucosyltransferase (4?CGT) is essential for aurone biosynthesis and yellow coloration in vivo. Coexpression of the Am4?CGT and AmAS1 genes was sufficient for the accumulation of aureusidin 6-O-glucoside in transgenic flowers (Torenia hybrida). Furthermore, their coexpression combined with down-regulation of anthocyanin biosynthesis by RNA interference (RNAi) resulted in yellow flowers. An Am4?CGT-GFP chimeric protein localized in the cytoplasm, whereas the AmAS1(N1-60)-RFP chimeric protein was localized to the vacuole. We therefore conclude that chalcones are 4?-O-glucosylated in the cytoplasm, their 4?-O-glucosides transported to the vacuole, and therein enzymatically converted to aurone 6-O-glucosides. This metabolic pathway is unique among the known examples of flavonoid, including anthocyanin biosynthesis because, for all other compounds, the carbon backbone is completed before transport to the vacuole. Our findings herein not only demonstrate the biochemical basis of aurone biosynthesis but also open the way to engineering yellow flowers for major ornamental species lacking this color variant. PMID:16832053

Ono, Eiichiro; Fukuchi-Mizutani, Masako; Nakamura, Noriko; Fukui, Yuko; Yonekura-Sakakibara, Keiko; Yamaguchi, Masaatsu; Nakayama, Toru; Tanaka, Takaharu; Kusumi, Takaaki; Tanaka, Yoshikazu

2006-01-01

135

Reversion of flowering  

Microsoft Academic Search

Reversion from floral to vegetative growth is under environmental control in many plant species. However the factors regulating\\u000a floral reversion, and the events at the shoot apex that take place when it occurs, have received less attention than those\\u000a associated with the transition to flowering.\\u000a \\u000a Reversions may be categorized as flower reversion, in which the flower meristem resumes leaf production,

N. H. Battey; R. F. Lyndon

1990-01-01

136

Delayed choice without choice  

E-print Network

A critical note on some of the existing proposals for performing the "delayed choice" experiment is placed. By abandoning the original idea and intention, some modern theoretical proposals and experimental evidence are simply incorrectly understood/interpreted. In effect, the Complementarity principle remains practically intact.

M. Dugic

2012-11-07

137

Color Constant Color Indexing  

Microsoft Academic Search

Objects can be recognized on the basis of their color alone by color indexing, a technique developed by Swain-Ballard (1991) which involves matching color-space histograms. Color indexing fails, however, when the incident illumination varies either spatially or spectrally. Although this limitation might be overcome by preprocessing with a color constancy algorithm, we instead propose histogramming color ratios. Since the ratios

Brian V. Funt; Graham D. Finlayson

1995-01-01

138

vol. 170, no. 4 the american naturalist october 2007 The Birds, the Bees, and the Virtual Flowers: Can Pollinator  

E-print Network

vol. 170, no. 4 the american naturalist october 2007 The Birds, the Bees, and the Virtual Flowers: Can Pollinator Behavior Drive Ecological Speciation in Flowering Plants?* Robert J. Gegear and James G variation in flower color to selection by live and virtual hummingbirds and bumblebees and track

Thomson, James D.

139

Physiologia Plantarum 2007 Copyright Physiologia Plantarum 2007, ISSN 0031-9317 Temperature-sensitive anthocyanin production in flowers  

E-print Network

-sensitive anthocyanin production in flowers of Plantago lanceolata Elizabeth A. Stilesa,b , Nadja B. Cecha , Stacy M-3054.2007.00855.x Flower color in the weedy perennial Plantago lanceolata is phenotypically plastic. Darker flowers, Lacey and Herr (2005) showed that for the weedy perennial, Plantago lanceolata L. (Plantagina- ceae

Lacey, Elizabeth P.

140

Bee inside flower retrieving nectar  

NSDL National Science Digital Library

The bee obtains nectar from the flower to make into honey. During this process, the bee is covered in pollen that will be transferred to other flowers for reproduction. Both the bee and the flower benefit from this process.

Katie Hale (California State University, Fullerton; Student, Biological Sciences)

2006-12-30

141

Occurrence of nudicaulin structural variants in flowers of papaveraceous species.  

PubMed

The intense color of yellow Papaver nudicaule flowers is conferred by the presence of nudicaulins, a group of alkaloids with a unique pentacyclic skeleton composed of an indole ring and a polyphenolic moiety. Petals from eight different Papaveraceae species composed of different color varieties were probed for the presence of nudicaulins. In addition to their occurrence in yellow P. nudicaule flowers, nudicaulins I-VIII were detected and quantified in orange flowers of P. nudicaule, and in yellow and orange Papaver alpinum flowers. Meconopsis cambrica petals showed a divergent nudicaulin spectrum, with compounds having an attached 3-hydroxy-3-methyl-glutaryl group (HMG) instead of a malonyl unit at one of the glucose units. Flavonols and anthocyanins that accompany nudicaulins were identified. The taxonomical significance of the occurrence of nudicaulins is briefly discussed. PMID:23684236

Tatsis, Evangelos C; Böhm, Hartmut; Schneider, Bernd

2013-08-01

142

Early Spring Flowers  

Microsoft Academic Search

YOUR readers will doubtless have been observing how the mildness of the weather this winter, so far, has hastened on the spring flowers. I am inclined to think that some of the dates mentioned below have not often been paralleled. The dates in brackets, of the usual flowering times, have been taken from Babington's ``Manual of Botany'' and Johnson's ``Gardeners'

E. Armitage

1898-01-01

143

Scholarship Awards, College Choice, and Student Engagement in College Activities: A Study of High-Achieving Low-Income Students of Color  

ERIC Educational Resources Information Center

Using two-wave survey data on the 2001 cohort of the Gates Millennium Scholarship (GMS) recipients and comparison nonrecipients, this study examines the relationship between scholarship awards and student engagement in college activities. The results indicate that scholarship awards such as GMS directly affect student college choice decisions.…

Hu, Shouping

2010-01-01

144

Radio Frequency Identification and Motion-sensitive Video Efficiently Automate Recording of Unrewarded Choice Behavior by Bumblebees  

PubMed Central

We present two methods for observing bumblebee choice behavior in an enclosed testing space. The first method consists of Radio Frequency Identification (RFID) readers built into artificial flowers that display various visual cues, and RFID tags (i.e., passive transponders) glued to the thorax of bumblebee workers. The novelty in our implementation is that RFID readers are built directly into artificial flowers that are capable of displaying several distinct visual properties such as color, pattern type, spatial frequency (i.e., “busyness” of the pattern), and symmetry (spatial frequency and symmetry were not manipulated in this experiment). Additionally, these visual displays in conjunction with the automated systems are capable of recording unrewarded and untrained choice behavior. The second method consists of recording choice behavior at artificial flowers using motion-sensitive high-definition camcorders. Bumblebees have number tags glued to their thoraces for unique identification. The advantage in this implementation over RFID is that in addition to observing landing behavior, alternate measures of preference such as hovering and antennation may also be observed. Both automation methods increase experimental control, and internal validity by allowing larger scale studies that take into account individual differences. External validity is also improved because bees can freely enter and exit the testing environment without constraints such as the availability of a research assistant on-site. Compared to human observation in real time, the automated methods are more cost-effective and possibly less error-prone. PMID:25489677

Orbán, Levente L.; Plowright, Catherine M.S.

2014-01-01

145

Radio Frequency Identification and motion-sensitive video efficiently automate recording of unrewarded choice behavior by bumblebees.  

PubMed

We present two methods for observing bumblebee choice behavior in an enclosed testing space. The first method consists of Radio Frequency Identification (RFID) readers built into artificial flowers that display various visual cues, and RFID tags (i.e., passive transponders) glued to the thorax of bumblebee workers. The novelty in our implementation is that RFID readers are built directly into artificial flowers that are capable of displaying several distinct visual properties such as color, pattern type, spatial frequency (i.e., "busyness" of the pattern), and symmetry (spatial frequency and symmetry were not manipulated in this experiment). Additionally, these visual displays in conjunction with the automated systems are capable of recording unrewarded and untrained choice behavior. The second method consists of recording choice behavior at artificial flowers using motion-sensitive high-definition camcorders. Bumblebees have number tags glued to their thoraces for unique identification. The advantage in this implementation over RFID is that in addition to observing landing behavior, alternate measures of preference such as hovering and antennation may also be observed. Both automation methods increase experimental control, and internal validity by allowing larger scale studies that take into account individual differences. External validity is also improved because bees can freely enter and exit the testing environment without constraints such as the availability of a research assistant on-site. Compared to human observation in real time, the automated methods are more cost-effective and possibly less error-prone. PMID:25489677

Orbán, Levente L; Plowright, Catherine M S

2014-01-01

146

Identification of Mendel's White Flower Character  

Microsoft Academic Search

BackgroundThe genetic regulation of flower color has been widely studied, notably as a character used by Mendel and his predecessors in the study of inheritance in pea.Methodology\\/Principal FindingsWe used the genome sequence of model legumes, together with their known synteny to the pea genome to identify candidate genes for the A and A2 loci in pea. We then used a

Roger P. Hellens; Carol Moreau; Kui Lin-Wang; Kathy E. Schwinn; Susan J. Thomson; Mark W. E. J. Fiers; Tonya J. Frew; Sarah R. Murray; Julie M. I. Hofer; Jeanne M. E. Jacobs; Kevin M. Davies; Andrew C. Allan; Abdelhafid Bendahmane; Clarice J. Coyne; Gail M. Timmerman-Vaughan; T. H. Noel Ellis

2010-01-01

147

Flowering and expression of flowering-related genes under long-day conditions with light-emitting diodes.  

PubMed

The effects of light quality on flowering time were investigated in Gypsophila paniculata, which is a long-day cut flower, and with Arabidopsis under long-day conditions with light-emitting diodes (LEDs). Gypsophila paniculata plants were grown under natural daylight and flowering was controlled by long-day treatment with a weak LED light of a single color in the night. Flowering was promoted not by blue light, but by far-red light in G. paniculata, while flowering was promoted by both light colors in Arabidopsis. FT homologs of G. paniculata GpFT1 and GpFT2 were differentially expressed under long-day conditions with white light, suggesting that they play roles in flowering at different stages of reproductive development. GpFTs and FT gene expression was not induced by far-red light in G. paniculata or Arabidopsis. Instead, the expression of the SOC1 homolog of G. paniculata GpSOC1 and SOC1 was induced by far-red light in G. paniculata and Arabidopsis. Flowering was promoted by induction of FT and SOC1 expression with blue light in Arabidopsis, whereas GpFTs and GpSOC1 expression was low with blue light induction in G. paniculata. The relationship between flowering and the expression of FT and SOC1 in Arabidopsis was confirmed with ft and soc1 mutants. These results suggest that long-day conditions with far-red light promote flowering through SOC1 and its homologs, while the conditions with blue light do not promote flowering in G. paniculata, because of low expression of GpFTs and GpSOC1 in contrast to that in Arabidopsis. PMID:21431295

Hori, Yoshimi; Nishidate, Koji; Nishiyama, Manabu; Kanahama, Koki; Kanayama, Yoshinori

2011-08-01

148

Say it with flowers  

PubMed Central

The timing of reproduction is a critical determinant of fitness, especially in organisms inhabiting seasonal environments. Increasing evidence suggests that inter-plant communication plays important roles in plant functioning. Here, we tested the hypothesis that flowering coordination can involve communication between neighboring plants. We show that soil leachates from Brassica rapa plants growing under long-day conditions accelerated flowering and decreased allocation to vegetative organs in target plants growing under non-inductive short-day conditions. The results suggest that besides endogenous signaling and external abiotic cues, flowering timing may involve inter-plant communication, mediated by root exudates. The study of flowering communication is expected to illuminate neglected aspects of plant reproductive interactions and to provide novel opportunities for controlling the timing of plant reproduction in agricultural settings. PMID:24598343

Falik, Omer; Hoffmann, Ishay; Novoplansky, Ariel

2014-01-01

149

Flower Constancy, Insect Psychology, and Plant Evolution  

NASA Astrophysics Data System (ADS)

Individuals of some species of pollinating insects tend to restrict their visits to only a few of the available plant species, in the process bypassing valuable food sources. The question of why this flower constancy exists is a rich and important one with implications for the organization of natural communities of plants, floral evolution, and our understanding of the learning processes involved in finding food. Some scientists have assumed that flower constancy is adaptive per se. Others argued that constancy occurs because memory capacity for floral features in insects is limited, but attempts to identify the limitations often remained rather simplistic. We elucidate now different sensory and motor memories from natural foraging tasks are stored and retrieved, using concepts from modern learning science and visual search, and conclude that flower constancy is likely to have multiple causes. Possible constraints favoring constancy are interference sensitivity of short-term memory, and temporal limitations on retrieving information from long-term memory as rapidly as from short-term memory, but further empirical evidence is needed to substantiate these possibilities. In addition, retrieving memories may be slower and more prone to errors when there are several options than when an insect copes with only a single task. In addition to memory limitations, we also point out alternative explanations for flower constancy. We then consider the way in which floral parameters, such as interplant distances, nectar rewards, flower morphology, and floral color (as seen through bees' eyes) affect constancy. Finally, we discuss the implications of pollinator constancy for plant evolution. To date there is no evidence that flowers have diverged to favor constancy, although the appropriate tests may not have yet been conducted. However, there is good evidence against the notion that pollinator constancy is involved in speciation or maintenance of plant species integrity.

Chittka, Lars; Thomson, James D.; Waser, Nickolas M.

150

Stars and Flowers, Flowers and Stars  

NASA Astrophysics Data System (ADS)

The author, a graduated from the Bucharest University (1964), actually living and working in Israel, concerns his book to variable stars and flowers, two domains of his interest. The analogies includes double stars, eclipsing double stars, eclipses, Big Bang. The book contains 34 chapters, each of which concerns various relations between astronomy and other sciences and pseudosciences such as Psychology, Religion, Geology, Computers and Astrology (to which the author is not an adherent). A special part of the book is dedicated to archeoastronomy and ethnoastronomy, as well as to history of astronomy. Between the main points of interest of these parts: ancient sanctuaries in Sarmizegetusa (Dacia), Stone Henge(UK) and other. The last chapter of the book is dedicated to flowers. The book is richly illustrated. It is designed for a wide circle of readers.

Minti, Hari

2012-12-01

151

Molecular characterization of mutations in white-flowered torenia plants  

PubMed Central

Background Torenia (Torenia fournieri Lind.) is a model plant increasingly exploited in studies in various disciplines, including plant engineering, biochemistry, physiology, and ecology. Additionally, cultivars with different flower colors have been bred and made commercially available. Flower color in torenia is mainly attributed to the accumulation of anthocyanins, but the molecular mechanisms inducing flower color mutations in torenia have not been well elucidated. In this study, we therefore attempted to identify the cause of white coloration in torenia by comparing the white-flowered cultivar Crown White (CrW) with Crown Violet (CrV), a violet-flowered variety. Results In an expression analysis, no flavanone 3-hydroxylase (TfF3H) transcript accumulation was detected in CrW petals. Sequence analyses revealed that a novel long terminal repeat (LTR)-type retrotransposable element, designated as TORE1 (Torenia retrotransposon 1), is inserted into the 5?-upstream region of the TfF3H gene in CrW. A transient expression assay using torenia F3H promoters with or without TORE1 insertion showed that the TORE1 insertion substantially suppressed F3H promoter activity, suggesting that this insertion is responsible for the absence of F3H transcripts in white petals. Furthermore, a transformation experiment demonstrated that the introduction of a foreign gentian F3H cDNA, GtF3H, into CrW was able to recover pink-flower pigmentation, indicating that F3H deficiency is indeed the cause of the colorless flower phenotype in CrW. Detailed sequence analysis also identified deletion mutations in flavonoid 3?-hydroxylase (TfF3?H) and flavonoid 3?,5?- hydroxylase (TfF3?5?H) genes, but these were not directly responsible for white coloration in this cultivar. Conclusions Taken together, a novel retrotransposable element, TORE1, inserted into the F3H 5?-upstream region is the cause of deficient F3H transcripts in white-flowered torenia, thereby leading to reduced petal anthocyanin levels. This is the first report of a retrotransposable element involved in flower color mutation in the genus Torenia. PMID:24694353

2014-01-01

152

Variation of Red Flower Mutant Line in Impatiens balsamina SP4 Generation Induced by Spaceflight  

Microsoft Academic Search

Red flower mutant line in Impatiens balsamina sp4 generation was developed from mutation plant by spaceflight. The differences of genomic DNA traits and content of flavonoids between mutant line with red flower color in SP4 generation Impatiens balsamina and its parent line (the ground control, CK) were investigated by using amplified inter simple sequence repeats (ISSR) markers and high performance

Ying Luo; Li Ma; Zhong-jun Jiang; Chun-xiang Bian; Ze-sheng Tang; Ming-hua Luo

2011-01-01

153

April showers bring May flowers…and May rains bring botrytis  

Technology Transfer Automated Retrieval System (TEKTRAN)

As the old saying goes “April showers bring May flowers” and to the greenhouse production industry May brings “color” to the greenhouse in the form of flowers which are good for both spring sales and Botrytis. This should not come as anything new to the seasoned grower, but hopefully will serve as ...

154

The Weta 39: 37-43 Two new remarkable flower flies (Diptera: Syrphidae)  

E-print Network

of these flies, the abdomen in life is a brilliant metallic purple color. No other syrphid in the world has among flower flies as their abdomens are flattened, striate and brilliant metallic purple in life

Mathis, Wayne N.

155

Variation among highbush blueberry cultivars for frost tolerance of open flowers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Injury of open flowers often occurs in fruit crops by late winter or early spring frosts and can result in significant reduction in yield. In this study, freezing tolerance of open flowers of five highbush blueberry cultivars, ‘Bluecrop’, ‘Elliott’, ‘Hannah’s Choice’, ‘Murphy’, and ‘Weymouth’, was d...

156

?????????????????????? chitosan ???????????????????????????????????????????????? Use of plant extracts and chitosan for postharvest control of flower thrips on chrysanthemum  

Microsoft Academic Search

The main problem of Chrysanthemum culture is destruction by insect pests, especially the flower thrips. Most agriculturists use pesticides to solve this problem and this causes other damage. Thus natural products should be a good new choice to replace or reduce the use of dangerous chemicals. In this study, we tested the efficiency of using natural products to lower flower

Kittiya Sangpakdee; Supanee Pimsamarn

157

Color Theory  

NSDL National Science Digital Library

This project will be used to teach the importance of color. Watch the following video about color Primary Colors Click on the link Exploration of Color. When you get into the website select the different colors to see what secondary colors are made from the primary colors. Review the following siteColor Theory and then design and paint a color wheel. ...

Mr. Sturgell

2009-12-02

158

Refuges, flower strips, biodiversity and agronomic interest.  

PubMed

Several arthropods are natural predators of pests, and they are able to reduce and control their population development. FREDON Nord Pas-de-Calais (Federation Regionate de Defense contre les Organismes Nuisibles = Regional Federation for Pest Control) has begun for a long time to form farmers to the recognition of beneficial arthropods and to show them their usefulness. These beneficial insects or arachnids are present everywhere, in orchards and even in fields which are areas relatively poor in biodiversity. Adults feed in the flower strips instead larvae and some adults feed on preys such as aphids or caterpillars. Most of the time, beneficial insects can regulate pest but sometimes, in agricultural area, they can't make it early enough and efficiently. Their action begin too late and there biodiversity and number are too low. It's possible to enhance their action by manipulating the ecological infrastructures, like sewing flower strips or installing refuges. Flower strips increase the density of natural enemies and make them be present earlier in the field in order to control pests. Refuges permit beneficial's to spend winter on the spot. So they're able to be active and to grow in number earlier. From 2004 to 2007, on the one hand, FREDON Nord Pas-de-Calais has developed a research program. Its purpose was to inventory practices and also tools and means available and to judge the advisability of using such or such beneficial refuge in orchards. On the second hand, it studied the impact in orchard of refuges on population of beneficial's and the difference there were between manufactured refuges and homemade refuges. Interesting prospects were obtained with some of them. Otherwise, since 2003, FREDON has studied flower strips influence on beneficial population and their impact on pest control. In cabbage fields, results of trials have shown that flower strips lead to a reduction of aphid number under acceptable economic level, up to 50 meters from flower strips. Results showed that in France it was mainly syrphids that control aphid populations. The choice of flowers Families to include in flower strip is important. You have to avoid choosing the same plant family as the one of the crop you want to protect because you would risk to attract pests and diseases in the field. In fact, it's important to choose the optimal diversity of plant Family and not the greatest diversity. PMID:19226774

Roy, Grégory; Wateau, Karine; Legrand, Mickaël; Oste, Sandrine

2008-01-01

159

Insects on flowers  

PubMed Central

Insect biodiversity peaks in tropical rainforest environments where a large but as yet unknown proportion of species are found in the canopy. While there has been a proliferation of insect biodiversity research undertaken in the rainforest canopy, most studies focus solely on insects that inhabit the foliage. In a recent paper, we examined the distribution of canopy insects across five microhabitats (mature leaves, new leaves, flowers, fruit and suspended dead wood) in an Australian tropical rainforest, showing that the density (per dry weight gram of microhabitat) of insects on flowers were ten to ten thousand times higher than on the leaves. Flowers also supported a much higher number of species than expected based on their contribution to total forest biomass. Elsewhere we show that most of these beetle species were specialized to flowers with little overlap in species composition between different canopy microhabitats. Here we expand our discussion of the implications of our results with respect to specialization and the generation of insect biodiversity in the rainforest canopy. Lastly, we identify future directions for research into the biodiversity and specialization of flower-visitors in complex tropical rainforests. PMID:23802039

Wardhaugh, Carl W.; Stork, Nigel E.; Edwards, Will; Grimbacher, Peter S.

2013-01-01

160

Notice—Bogor botanical garden flower transparencies available  

Microsoft Academic Search

As a service to American plant taxonomists who use color transparencies in their teaching, I am pleased to announce the availability of Kodachrome and Ektachrome 2 Ť 2 transparencies of tropical plants and their flowers or fruits made at the world famous Bogor Botanical Gardens in Indonesia. These photographs are mostly from the Garden itself, taken by members of the

Richard M. Straw

1969-01-01

161

POLYGALA MYRTIFOLIA 'CHAPMAN FIELD', AN OUTSTANDING NEW SUBTROPICAL FLOWERING SHRUB  

Technology Transfer Automated Retrieval System (TEKTRAN)

Polygala myrtifolia, Cape milkwort, is a showy evergreen shrub that ranges throughout South Africa in both winter and summer rainfall areas, occurring in diverse vegetation types and on many different soils. Flower color, mostly shades of purple, can also range from pink to white. It reaches a hei...

162

Extension Bulletin E-1844 (New) August 1985 Forcing Flowering Branches  

E-print Network

ornamental trees and shrubs and "forcing" them to bloom indoors during winter is a simple, colorful way in a dimly lighted location at 60-65°F. Although branches could be brought into full sun and room the flowers last longer. A cool room or the coolest location in a room #12;MSU Extension Publication Archive

163

8.G Flower Vases  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: My sister’s birthday is in a few weeks and I would like to buy her a new vase to keep fresh flowers in her house. She often forgets to water her flower...

164

Flower orientation enhances pollen transfer in bilaterally symmetrical flowers.  

PubMed

Zygomorphic flowers are usually more complex than actinomorphic flowers and are more likely to be visited by specialized pollinators. Complex zygomorphic flowers tend to be oriented horizontally. It is hypothesized that a horizontal flower orientation ensures effective pollen transfer by facilitating pollinator recognition (the recognition-facilitation hypothesis) and/or pollinator landing (the landing-control hypothesis). To examine these two hypotheses, we altered the angle of Commelina communis flowers and examined the efficiency of pollen transfer, as well as the behavior of their visitors. We exposed unmanipulated (horizontal-), upward-, and downward-facing flowers to syrphid flies (mostly Episyrphus balteatus), which are natural visitors to C. communis. The frequency of pollinator approaches and landings, as well as the amount of pollen deposited by E. balteatus, decreased for the downward-facing flowers, supporting both hypotheses. The upward-facing flowers received the same numbers of approaches and landings as the unmanipulated flowers, but experienced more illegitimate landings. In addition, the visitors failed to touch the stigmas or anthers on the upward-facing flowers, leading to reduced pollen export and receipt, and supporting the landing-control hypothesis. Collectively, our data suggested that the horizontal orientation of zygomorphic flowers enhances pollen transfer by both facilitating pollinator recognition and controlling pollinator landing position. These findings suggest that zygomorphic flowers which deviate from a horizontal orientation may have lower fitness because of decreased pollen transfer. PMID:19333624

Ushimaru, Atushi; Dohzono, Ikumi; Takami, Yasuoki; Hyodo, Fujio

2009-07-01

165

Introducing Fractions Slideshow- Flowering Fractions  

NSDL National Science Digital Library

This online resource is a story of a girl and her father planting flowers that your children and you interact with. Help them fill in the fractions as they practice dividing the garden up for their flowers!

Beacon Learning Center

2011-10-24

166

Flower constancy in insect pollinators  

PubMed Central

As first noted by Aristotle in honeybee workers, many insect pollinators show a preference to visit flowers of just one species during a foraging trip. This “flower constancy” probably benefits plants, because pollen is more likely to be deposited on conspecific stigmas. But it is less clear why insects should ignore rewarding alternative flowers. Many researchers have argued that flower constancy is caused by constraints imposed by insect nervous systems rather than because flower constancy is itself an efficient foraging method. We argue that this view is unsatisfactory because it both fails to explain why foragers flexibly adjust the degree of flower constancy and does not explain why foragers of closely related species show different degrees of constancy. While limitations of the nervous system exist and are likely to influence flower constancy to some degree, the observed behavioural flexibility suggests that flower constancy is a successful foraging strategy given the insect’s own information about different foraging options. PMID:22446521

Ratnieks, Francis L.W.

2011-01-01

167

In vitro flowering of orchids.  

PubMed

Flowering is the most elusive and fascinating of all plant developmental processes. The ability to induce flowering in vitro in orchids would reduce the relatively long juvenile phase and provide deeper insight into the physiological, genetic and molecular aspects of flowering. This review synthesizes all available studies that have been conducted on in vitro flowering of orchids with the objective of providing valuable clues as to the mechanism(s) that is possibly taking place. PMID:23883072

Teixeira da Silva, Jaime A; Kerbauy, Gilberto B; Zeng, Songjun; Chen, Zhilin; Duan, Jun

2014-03-01

168

Flower biology in New Zealand  

Microsoft Academic Search

Research on flower biology began in New Zealand in the early 1870s under the influence of Darwin's work on orchids, but from the turn of the century there was a decline in interest until the 1950s. Spring and summer are the main flowering periods, but many species flower in winter and examples are described. Of some 1800 indigenous species of

E. J. Godley

1979-01-01

169

Photoperiodic induction of synchronous flowering  

E-print Network

of synchronous flowering near the Equator Rolf Borchert1 , Susanne S. Renner2 , Zoraida Calle3 , Diego Navarrete4 . At these low population densities, successful cross-pollination relies on synchronous flowering. In rainforests synchronous flowering2,3 . This poses a problem because there is no variation in day length at the Equator

Renner, Susanne

170

Environmental regulation of flowering.  

PubMed

The timing of flower initiation is a highly plastic developmental process. To achieve reproductive success, plants must select the most favourable season to initiate reproductive development; this in turn requires continuous monitoring of environmental factors and a properly response. Environmental factors which change in a predictable fashion along the year, such as light and temperature, are the most relevant in terms of selection of the flowering season. In Arabidopsis and more recently in a few other species, molecular genetic analyses are providing a way to identify the genes involved in the regulation of flowering time. From gene sequences it is possible to develop hypotheses regarding molecular function and to infer some of the molecular mechanisms involved in the environmental regulation of flowering time. In this paper, we summarize recent discoveries concerning the mechanisms which plants use to perceive and respond to major environmental factors (light and temperature) and their different components. We focus mainly on annual plants and especially on Arabidopsis because most of the available molecular and functional data come from this species. However, additional information arising from other plant systems is also considered. PMID:16096975

Ausín, Israel; Alonso-Blanco, Carlos; Martínez-Zapater, José-Miguel

2005-01-01

171

Flowers of Wisteria floribunda  

NSDL National Science Digital Library

Flowers of Wisteria floribunda, a well-known ornamental plant from East Asia. Wisteria has been placed in the predominantly tropical tribe Millettieae by its morphological similarities. However, molecular evidence suggests that Wisteria and a tropical genus Callerya are closer to many temperate herbaceous legumes but not to other Millettieae members.

Jer-Ming Hu (University of California; Section of Evolution and Ecology ADR; POSTAL)

2004-03-09

172

Morning glory flower  

NSDL National Science Digital Library

The stamens consist of pollen producing anthers (brown balls) attached to filaments (white stalks). Pollen is the equivalent of sperm. The carpels consist of stigmas (white tip) attached to styles (white stalks) at the center of the flower. The style leads to the ovary at the base of the carpel (which makes eggs).

Katie Hale (CSUF; Biological Sciences)

2007-06-19

173

School Choice.  

ERIC Educational Resources Information Center

This publication is the first in a series of reports that examine policy issues in education. It looks at the four major forms of school choice--charter schools, open enrollment, home schooling, and vouchers--and how they are changing the landscape of public education. School choice is one of the fastest-growing innovations in public education,…

The Progress of Education Reform 1999-2001, 1999

1999-01-01

174

Flower drinking and masculinity in Taiwan.  

PubMed

This study explores the role of the hostess club culture in the creation and maintenance of masculinity in Taiwan. The article focuses on flower drinking (the consumption of alcohol in bars, often integrated with prostitution), which is a common practice in Taiwan. Data were obtained from 58 in-depth interviews with men from a variety of occupations and social backgrounds (mean age = 38.50, SD = 11.00) and 73 questionnaires administered to soldiers (mean age = 21.00, SD = 1.10). Findings indicated that demonstration of skill at flower drinking and facility with the related social etiquette are important channels for male bonding that were central to the mid- to upper-class participants' professional development. Flower drinking also provided a method of discriminating men from other men through their choices of why and where to go and how to behave while there. Specific ways that Taiwanese masculinity differs from Western and from Japanese masculinity, and support for the continuing relevance of the traditional Confucian ideal of masculinity, wen-wu, are discussed. PMID:19763998

Bedford, Olwen; Hwang, Shu-Ling

2011-01-01

175

Flower-Like Nanopowders  

NASA Astrophysics Data System (ADS)

Yttrium-doped Y x Bi2- x Te3 ( x = 0.15, 0.2, 0.25) flower-like nanopowders were synthesized by the hydrothermal method through careful adjustment of the amount of ethylenediaminetetraacetic acid surfactant. The flower-like nanopowders were hot pressed into bulk pellets, and the thermoelectric properties of the pellets were examined. The results showed that the optimized doped sample Y0.25Bi1.75Te3 had a relatively high Seebeck coefficient, a lower electrical resistivity, and a lower thermal conductivity. As a result, the figure of merit of the n-type Y0.25Bi1.75Te3 alloy reached 1.23 at 410 K.

Shi, Wenyu; Wu, Fang; Wang, Kunlun; Yang, Jingjing; Song, Hongzhang; Hu, Xing

2014-09-01

176

Fish and Flowers  

NSDL National Science Digital Library

We all know rain makes the flowers grow but sometimes fish help too. Thats according to University of Florida ecologist Robert Holt. He and his colleagues studied eight freshwater ponds. There, bees pollinate nearby flowers, while dragonflies prey on the bees. But fish control the dragonfly population by eating their larvae. Holts team compared the flora around ponds with fish to ponds without. Ponds that had fish in them tended to have fewer larval dragonflies, and fewer adult dragonflies which meant more bees, and more frequent pollinations. Plants around fishless ponds, on the other hand, were more likely to be pollen starved. The study suggests one way that the effects of overfishing may ripple onto land. A more complete description of the research and a transcript of the audio file is included. In addition, links to additional resources are included for further inquiry.

American Association for the Advancement of Science (; )

2005-12-05

177

Flowering and Pollination  

NSDL National Science Digital Library

This pdf includes background information and an activity for engaging students in the processes that occur during pollination, fertilization and seed development in Fast Plants. Pollination is explained and illustrated and an activity for students to pollinate Fast Plants and observe reproductive development is described.In participating in this activity students will:? understand flowering as the sexually mature stage of plant development;? understand where and how ovules and pollen originate (male and female gamete formation);? explore the parts of the flower and the role that each part plays in reproduction;? observe the reproductive tissues of plants, including pollen and stigma, under magnification;? understand the interdependent coevolutionary relationship of bees and brassicas; and? begin the process of reproduction in their Fast Plants by performing a pollination using a beestick,? setting the stage for future developmental events.

The Wisconsin Fast Plants Program

178

Inflorescence with Flowers of Purple Loosestrife, Lythrum salicaria  

NSDL National Science Digital Library

Inflorescence with flowers of purple loosestrife, Lythrum salicaria (left panel). Depending on the relative length of styles with respect to stamens within flowers, individuals are categorized into three floral morphs. The three floral morphs also differ in size and shape of stigmas (right panel). Stigmas (top?long morph, middle?mid morph, and bottom?short morph, in the right panel; bar = 200 µm) are digitally false-colored computer-enhanced images from scanning electron micrographs. Photo credit: M. Biernacki, T. K. Mal, R. J. Williams, and The Camera Shop, Broomall, Pennsylvania.

2004-03-09

179

How flowers catch raindrops  

Microsoft Academic Search

Several species of plants have raindrop-sized flowers that catch raindrops opportunistically in order to spread their 0.3-mm seeds distances of over 1 m. In the following fluid dynamics video, we show examples of these plants and some of the high speed videography used to visualize the splash dynamics responsible for raindrop-driven seed dispersal. Experiments were conducted on shape mimics of

Guillermo Amador; Yasukuni Yamada; David Hu

2011-01-01

180

Conservatory of Flowers  

NSDL National Science Digital Library

San Francisco's Conservatory of Flowers at Golden Gate Park has recently reopened to the public after a year of renovation to repair damage from a devastating windstorm in 1995. The Conservatory's attractive Web site offers a virtual tour, highlighting the Conservatory's "dramatic new exhibits and horticultural displays." Visitors can also learn more about featured plants (palms, at the moment), check out an online photo gallery, and learn all about the restoration of Conservatory buildings and displays.

181

Color blindness  

MedlinePLUS

Color deficiency; Blindness - color ... Color blindness occurs when there is a problem with the pigments in certain nerve cells of the eye that sense color. These cells are called cones. They are found ...

182

Color Blindness  

MedlinePLUS

... three color cone cells to determine our color perception. Color blindness can occur when one or more ... Anyone who experiences a significant change in color perception should see an ophthalmologist (Eye M.D.). Next ...

183

76 FR 60447 - Florigene Pty., Ltd.; Determination of Nonregulated Status for Altered Color Roses  

Federal Register 2010, 2011, 2012, 2013, 2014

...1-9, which have been genetically engineered to produce novel flower color, are no longer considered a regulated article under our...1-9, which have been genetically engineered to produce novel flower color. The petition stated that these rose lines are...

2011-09-29

184

Choice between concurrent schedules1  

PubMed Central

Six pigeons pecked for food in a three-key experiment. A subject at any time could choose the left or right key and receive reinforcement according to one two-key concurrent variable-interval variable-interval schedule of reinforcement, or it could peck the center key. A peck on the center key arranged the complementary two-key concurrent variable-interval variable-interval schedule on the left and right keys. The two different two-key concurrent schedules arranged reinforcements concurrently and were signalled by two different colors of key lights. Choice behavior in the presence of a given color conformed to the usual relationship in two-key concurrent schedules: the relative frequency of responding on a key approximately equalled the relative frequency of reinforcement on that key. Preference for a two-key concurrent schedule, which was equivalent to preference for a color, was measured by the percentage of all responses on the left and right keys in the presence of that color: this percentage approximately equalled the percentage of all reinforcements that were delivered in the presence of that color. Thus, choice between concurrent schedules conforms approximately to the same relationship as does choice between alternatives in a single concurrent schedule. PMID:16811668

Menlove, Ronald L.; Moffitt, Marilynne; Shimp, Charles P.

1973-01-01

185

Biology, Ecology and Management of Flowering Rush  

E-print Network

Biology, Ecology and Management of Flowering Rush (Butomus umbellatus) Hilary Parkinson, Research December 2010 #12;PL ANT BIOLOGY Identification Flowering rush is an aquatic species resembling a large). Flowering rush belongs to its own family, Butomaceae. Flowering rush is easy to identify when flowering; 20

Maxwell, Bruce D.

186

Flower Evolution: The Origin and Subsequent Diversification  

E-print Network

Flower Evolution: The Origin and Subsequent Diversification of the Angiosperm Flower Chelsea D trends, flower organ identity, MADS-box Abstract Developmental genetic pathways involved in flower networks that are involved in the regulation of flower initiation, growth and differentiation. These genes

187

Color Confinement and Massive Gluons  

E-print Network

Color confinement is one of the central issues in QCD so that there are various interpretations of this feature. In this paper we have adopted the interpretation that colored particles are not subject to observation just because colored states are unphysical in the sense of Eq. (2.16). It is shown that there are two phases in QCD distinguished by different choices of the gauge parameter. In one phase, called the "confinement phase", color confinement is realized and gluons turn out to be massive. In the other phase, called the "deconfinement phase", color confinement is not realized, but the gluons remain massless.

M. Chaichian; K. Nishijima

2005-11-15

188

Flower scents from the Pacific.  

PubMed

For a long time, exotic scents from the islands of the South Pacific have universally been appreciated. Most frequently, fragrant flowers (e.g., frangipani, jasmine sambac, tiaré, pua kenikeni) are used locally for ornamental purposes such as flower garlands (leis). Despite their powerful and delightful fragrance, very few of these flowers have been commercially employed in this part of the world for perfume manufacturing. Creative perfumers are nevertheless strongly interested to better understand these fragrances and to use them, either genuine or artificially reconstituted. Analytical results on the fragrance of these flowers are reported, together with some economical considerations. PMID:18618387

Joulain, Daniel

2008-06-01

189

Flower senescence: some molecular aspects.  

PubMed

Some molecular aspects of flower senescence have been reviewed. The isolation, identification and characterization of different genes from various flowers (mainly from petals) associated with senescence have been discussed. The isolated genes were divided into different groups. A large proportion of genes have been found to be upregulated during flower senescence while some genes were also found to be downregulated indicating that there exists a complex interplay between the expression patterns of various genes. The genes involved in petal expansion are found to be upregulated during normal flower development from anthesis to open flower stage, but XTH (Xyloglucan endotransglucosylase hydrolase) is found to be involved in petal expansion as well as abscission. Cysteine proteases or the genes encoding cysteine proteases (assigned a central role in protein degradation) have been identified from various flower systems, but no cysteine protease has been identified from senescing Mirabilis jalapa flowers. In addition to proteases, the genes encoding ubiquitin (exhibiting proteasomal degradation by 26S proteasomes) have also been identified suggesting the two alternate pathways for protein degradation. Genes encoding specific nucleases have also been identified, but they displayed an early increase in transcript abundance before the senescence symptoms become evident and characterize the involvement of PCD during flower senescence. A range of transcription factors are described and their possible role in flower senescence has been discussed. A detailed description of genes involved in ethylene synthesis and the components involved in ethylene signaling have been presented. PMID:24178586

Shahri, Waseem; Tahir, Inayatullah

2014-02-01

190

FLOWERING LOCUS C Encodes a Novel MADS Domain Protein That Acts as a Repressor of Flowering  

Microsoft Academic Search

Winter-annual ecotypes of Arabidopsis are relatively late flowering, unless the flowering of these ecotypes is promoted by exposure to cold (vernalization). This vernalization-suppressible, late-flowering phenotype results from the presence of dominant, late-flowering alleles at two loci, FRIGIDA ( FRI ) and FLOWERING LOCUS C ( FLC ). In this study, we report that flc null mutations result in early flowering,

Scott D. Michaels; Richard M. Amasino

1999-01-01

191

It's time to flower: the genetic control of flowering time  

Microsoft Academic Search

Summary In plants, successful sexual reproduction and the ensu- ing development of seeds and fruits depend on flowering at the right time. This involves coordinating flowering with the appropriate season and with the developmental historyoftheplant.Geneticandmolecular analysisinthe small cruciform weed, Arabidopsis, has revealed distinct butlinkedpathwaysthatareresponsiblefordetectingthe major seasonal cues of day length and cold temperature, as well as other local environmental and

Jo Putterill; Rebecca Laurie; Richard Macknight

2004-01-01

192

Colored Shadows  

NSDL National Science Digital Library

In this optics activity, learners discover that not all shadows are black. Learners explore human color perception by using colored lights to make additive color mixtures. With three colored lights, learners can make shadows of seven different colors. They can also explore how to make shadows of individual colors, including black. Use this activity demonstrate how receptors in the retina of the eye work to see color.

2011-10-31

193

Teaching Through Trade Books: Flower Power  

NSDL National Science Digital Library

Summer is here and flowers are in bloom! Each flowering plant produces a unique bloom that provides opportunities for students to make observations about plants. By comparing and contrasting flowers, students can connect their learning to the larger pictu

Christine Anne Royce

2009-07-01

194

The influence of pigmentation patterning on bumblebee foraging from flowers of Antirrhinum majus  

NASA Astrophysics Data System (ADS)

Patterns of pigmentation overlying the petal vasculature are common in flowering plants and have been postulated to play a role in pollinator attraction. Previous studies report that such venation patterning is significantly more attractive to bee foragers in the field than ivory or white flowers without veins. To dissect the ways in which venation patterning of pigment can influence bumblebee behaviour, we investigated the response of flower-naďve individuals of Bombus terrestris to veined, ivory and red near-isogenic lines of Antirrhinum majus. We find that red venation shifts flower colour slightly, although the ivory background is the dominant colour. Bees were readily able to discriminate between ivory and veined flowers under differential conditioning but showed no innate preference when presented with a free choice of rewarding ivory and veined flowers. In contrast, both ivory and veined flowers were selected significantly more often than were red flowers. We conclude that advantages conferred by venation patterning might stem from bees learning of their use as nectar guides, rather than from any innate preference for striped flowers.

Whitney, Heather M.; Milne, Georgina; Rands, Sean A.; Vignolini, Silvia; Martin, Cathie; Glover, Beverley J.

2013-03-01

195

On the Function of Flowers  

Microsoft Academic Search

Most flowers are bisexual in function, but counting secondary allocation to attractive structures such as the corolla as equally male and female leads to the paradoxical conclusion that plants bearing perfect flowers invariably allocate much more to female than to male function. A method of calculating the gender of secondary floral allocation is described, and it is speculated that this

G. Bell

1985-01-01

196

Flowers: More Than Just Pretty  

NSDL National Science Digital Library

Children love to look at flowers but few are inclined to become familiar with the structure and function of the flower. This story is aimed at providing some motivation for children to learn about one of the most important evolutionary developments in the

Richard Konicek-Moran

2009-04-01

197

Stop and Paint the Flowers.  

ERIC Educational Resources Information Center

Describes an art lesson where students used watercolors to paint a flower bouquet arranged in a vase. Explains that the students viewed examples of flower bouquets by artists such as Vincent van Gogh and Odilon Redon. Discusses, in detail, the process of creating the artworks. (CMK)

Phillips, Shelley

2002-01-01

198

Early Flower Development in Arabidopsis  

Microsoft Academic Search

The early development of the flower of Arabidopsis thaliana is described from initiation until the opening of the bud. The morphogenesis, growth rate, and surface structure of floral organs were recorded in detail using scanning electron microscopy. Flower development has been divided into 12 stages using a series of landmark events. Stage 1 begins with the initiation of a floral

David R. Smyth; John L. Bowman; Elliot M. Meyerowitz

1990-01-01

199

Colorful Creatures  

NSDL National Science Digital Library

For animals, bright, flashy coloration can serve as a warning or as an invitation. Either way, colorful skin, feathers, and scales yell, Notice me! This collection of images shows examples of some of the world's most colorful creatures.

WGBH Educational Foundation

2003-09-26

200

What is color for? Color  

E-print Network

What is color for? #12;#12;#12;#12;#12;#12;#12;#12;#12;Color · Physics ­ Light is E-M radiation of different frequencies. ­ Superposition principle · Perception ­ 3 cones -> 3D color space. (Metamers). ­ Convex subset of 3D linear space. ­ Color matching: can't represent w/ 3 primaries. · Color Spaces ­ CIE

Jacobs, David

201

Colouration in crab spiders: substrate choice and prey attraction.  

PubMed

Australian crab spiders Thomisus spectabilis ambush pollinating insects, such as honeybees (Apis mellifera) on flowers, and can change their body colour between yellow and white. It is traditionally assumed that the spiders change their colour to match the flower colour, thus rendering them cryptic to insect prey. Here, we test this assumption combining state-of-the-art knowledge of bee vision and behavioural experiments. In the field, yellow spiders are only found on yellow daisies (Chrysanthemum frutescens), whereas white spiders are found on yellow and white daisies. These field patterns were confirmed in the laboratory. When given the choice between white and yellow daisies, yellow spiders preferred yellow daisies, whereas white spiders showed only a slight but non-significant preference for white flowers. Thus, T. spectabilis select background colours according to their own body colour. When viewed from a distance, bees use an achromatic signal produced by their green receptors for target detection. Through this visual channel, white spiders on white flowers, and yellow spiders on yellow flowers are virtually undetectable. From a closer distance of a few centimetres, when bees evaluate colour contrast, the combination of spider colour against different flower backgrounds affected the response of honeybees, but not in ways predicted by a classical crypsis/conspicuousness interpretation. Yellow spiders on yellow flowers are not perfectly matched when interpreted through the colour vision of a honeybee. Nevertheless, honeybees showed indifference to the presence of a spider, equally landing on vacant or spider-occupied flowers. Likewise, white spiders are poorly hidden on white flowers, as white spiders reflect ultraviolet light strongly, while white flowers do not. Surprisingly, bees are attracted to this contrast, and significantly more honeybees preferred white flowers occupied by white spiders. White spiders on yellow flowers produce the highest colour contrast and bees again preferred spider-occupied flowers. Yellow spiders on white flowers were the only pairing where bees rejected spider-occupied flowers, especially in cases where the contrast between the two was relatively strong. Thus, T. spectabilis select flower colours adaptively in a way that deceives honeybees, or at least does not deter them. PMID:15879060

Heiling, Astrid M; Chittka, Lars; Cheng, Ken; Herberstein, Marie E

2005-05-01

202

Color realism and color science  

E-print Network

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, ...

Byrne, Alex

203

Chasmogamous Flowering in Viola palustris L  

Microsoft Academic Search

AFTER a short burst of chasmogamous flowering in early spring, plants of V. palustris, like those of many other violet species, produce a succession of cleistogamous flowers throughout the summer. Such a change in flowering habit could be associated with changes in day-length, as in V. fimbriatula and V. papilionacea with which Allard and Garner1 obtained chasmogamous flowers only in

L. T. Evans

1956-01-01

204

Down the tube: pollinators, predators, and the evolution of flower shape in the alpine skypilot, Polemonium viscosum.  

PubMed

We address how a conflict between pollinator attraction and avoidance of flower predation influences the evolution of flower shape in Polemonium viscosum. Flower shape in P. viscosum is the product of an isometric relationship between genetically correlated (rA = 0.70) corolla flare and length. Bumblebee pollinators preferentially visit flowers that are more flared and have longer tubes, selecting for a funnel-shaped corolla. However, flower shape also influences nectar-foraging ants that sever the style at its point of attachment to the ovary. Surveys of ant damage show that plants having flowers with flared, short corollas are most vulnerable to ant predation. Consistent with this result, the ratio of corolla length to flare is significantly greater in a krummholz (high predation risk) population than in a tundra (low predation risk) population. To explicitly test whether the evolution of a better defended flower would exact a cost in pollination, we created tubular flowers by constricting the corolla during development. Performance of tubular flowers and natural controls was compared for defensive and attractive functions. In choice trials, ants entered control flowers significantly more often than tubular ones, confirming that the evolution of tubular flowers would reduce the risk of predation. However, in a bumblebee-pollinated population, tubular flowers received significantly less pollen and set fewer seeds than controls. A fitness model incorporating these data predicts that in the absence of the genetic correlation between corolla length and flare, intermittent selection for defense could allow tubular flowers to spread in the krummholz population. However, in the tundra, where bumblebees account for nearly all pollination, the model predicts that tubular flowers should always confer a fitness disadvantage. PMID:11761057

Galen, C; Cuba, J

2001-10-01

205

Genetic architecture of flowering time in A. thaliana Genetic architecture of flowering time variation  

E-print Network

Genetic architecture of flowering time in A. thaliana 1 Genetic architecture of flowering time.126607 Copyright 2011. #12;Genetic architecture of flowering time in A. thaliana 2 Running title: Genetic architecture of flowering time in A. thaliana Keywords: Arabidopsis thaliana, flowering time, QTL, FLC, FLM

Weigel, Detlef

206

Quark flowers and quark condensation  

E-print Network

The mass formation of basic vector mesons up to energy 3.8 GeV was studied. The investigation was done with using of jet mechanism, the harmonic quarks and neutral colorless groups. The stage of a whole string with a zero interquark momentum was considered as a separate stage of hadronization. The quark group with rest mass equal to experimental mass of hadron was named as flower. The quark flowers were found for $\\rho$, $\\omega$, $\\varphi$, $\\psi/J$, $\\psi$(2S) and $\\psi$(3770). The flower mass of $\\psi$(2S) was defined as 3686.09 MeV. The structure of quark flowers is symmetrical and consists from an aura and central part. The formation of quark shells, the condensation of quarks on the quark leaders, the floral schemes of kaon formation and complicated hadronization are discussed.

Oleg A. Teplov

2009-06-09

207

Farming and Gardening: Flower Garden  

NSDL National Science Digital Library

In this activity, students will Explore the relationships between fractions and percents while creating a grid of different flowers in a garden. Then the students will combine this grid with others to apply the concepts to a larger set.

PBS TeacherSource - Math

2010-01-01

208

Colorful Chemistry.  

ERIC Educational Resources Information Center

Described is an color-making activity where students use food coloring, eyedroppers, and water to make various colored solutions. Included are the needed materials and procedures. Students are asked to write up the formulas for making their favorite color. (KR)

Williams, Suzanne

1991-01-01

209

Color Addition  

NSDL National Science Digital Library

This activity is inquiry in that students do not know how colors are combined. They likely think that the primary colors are red, yellow, and blue. In fact, there are two sets of primary colors: red, green, and blue for additive colors of light, and cyan,

Michael Horton

2009-05-30

210

How Our Environment Affects Color Vision  

NSDL National Science Digital Library

In this lab (Activity #1 on page), learners explore how we see color. Learners set up an experiment to evaluate how a group of learners view different colors as presented on different background colors and under different lighting conditions. Learners collect data and then answer questions to help them analyze their findings. Learners will consider how designers make choices about colors when creating products and marketing materials.

2012-06-26

211

Color Mixing  

NSDL National Science Digital Library

This is an online activity where learners can virtually mix different colors of light or paint (you can switch between them) and see how the colors combine. It demonstrates how millions of colors are created on computer monitors and TVs, and in art and printing. Learners can try to match a given target color ("Mix to Match"), or simply play around with mixtures ("Mix for Fun"). Background information explains how light is additive (more colors tends towards white), whereas paint absorbs color and is subtractive (more colors tends towards black). There's also information about how the human eye works.

Oregon Museum of Science and Industry

2002-01-01

212

The Scent of Lotus Flowers  

Microsoft Academic Search

A solvent extract of Nelumbo nucifera ‘Shinnyoren’ flowers was investigated by GC and GC\\/MS. Seventy compounds were identified with the major constituents being hydrocarbons representing more than 75% of the extract. 1,4-Dimethoxybenzene, 1,8-cineole, terpinen-4-ol and linalool were found to be indispensible in characterizing the scent of lotus flower. Using headspace analysis, the volatiles of 44 cultivars of N. nucifera, one

Akihiko Omata; Katsuyuki Yomogida; Shoji Nakamura; Tadao Ohta; Yasuko Izawa; Satomi Watanabe

1991-01-01

213

The Color of Children’s Gender Stereotypes  

Microsoft Academic Search

To examine the impact of gender and gender-related color stereotypes, 98 Israeli preschoolers and 3rd graders chose between\\u000a booklets mismatched in the stereotypicality of color (pink vs. blue) versus illustration (Batman vs. Bratz) and subsequently\\u000a colored gender-stereotyped versus gender-neutral illustrations with male and female-stereotyped color crayons. Color was ignored\\u000a in booklet choice. More colors were used for figures stereotypically associated

Rachel Karniol

2011-01-01

214

Spirit Has Flower Power  

NASA Technical Reports Server (NTRS)

The Mars Exploration Rover Spirit took this image with its hazard-avoidance camera on sol 86 (March 31, 2004), after the rover's rock abrasion tool had brushed for three minutes on each of six locations on the rock named 'Mazatzal' to create a flower-shaped mosaic.

The goal for this operation was to create a brushed area big enough for the miniature thermal emission spectrometer to capture within one of its pixels, which are 11 centimeters (4.3 inches) in diameter at the distance between the rock and the instrument. Because the rock abrasion tool creates individual brushed areas only about 5 centimeters (2 inches) in diameter, the team designed this six-location series of tool placements in order to brush 92 percent to 95 percent of the spectrometer's pixel size.

This operation was only the second time the rock abrasion tool has created a brushing mosaic. The first time was a three-spot brushing on the rock called 'Humphrey.' The brush was originally designed to be used as an aide during full grinding operations, however it has been very effective in brushing the top layer off of dusty martian rocks to allow scientists a multi-depth look into the rocks on Mars.

2004-01-01

215

Differential gene expression analysis by cDNA-AFLP between flower buds of Phalaenopsis Hsiang Fei cv. H. F. and its somaclonal variant  

Microsoft Academic Search

Somaclonal variation occurs during plant tissue culture and introduces changes that can result in the development of desirable traits. Using cDNA-amplified restriction fragment length polymorphism (cDNA-AFLP) analysis, we compared gene expression patterns between flower buds from wild type (donor) plants of Phalaenopsis Hsiang Fei cv. H. F., whose flowers are bronze in color, and from its somaclonal variants, whose flowers

Tsai-Wei Hsu; Wen-Chieh Tsai; Dan-Ping Wang; Sandy Lin; Yu-Yun Hsiao; Wen-Huei Chen; Hong-Hwa Chen

2008-01-01

216

Color distance derived from a receptor model of color vision in the honeybee  

Microsoft Academic Search

A model calculation is presented for investigating the domain between the two well-examined fields of color vision in the bee, i.e. choice behavior with respect to color stimuli, and photoreceptor physiology. Based on the properties of the receptors, the model explains quantitatively the results obtained in color discrimination experiments. The model predicts curved lines which connect the loci of most

W. Backhaus; R. Menzel

1987-01-01

217

Different color Same color Similarityrating  

E-print Network

1 2 3 4 5 6 7 8 9 Different color Same color Similarityrating Object pair A central principle color localizer. Feature diagnosticity affects semantic representations of novel and common object. blobby 3. round 4. Using color as the diagnostic feature, we used a training paradigm to investigate how

Thompson-Schill, Sharon

218

Bright color reflective displays with interlayer reflectors  

NASA Astrophysics Data System (ADS)

A good solution to the reflective display of color has been a major challenge for the display industry, with very limited color gamuts demonstrated to date. Conventional side-by-side red, green and blue color filters waste two-thirds of incident light. The alternative of stacking cyan, magenta and yellow layers is also challenging -- a 10% loss per layer compounds to nearly 50% overall. Here we demonstrate an architecture that interleaves absorbing-to-clear shutters with matched wavelength selective reflectors. This increases color gamut by reducing losses and more cleanly separating the color channels, and gives much wider choice of electro-optic colorants.

Kitson, Stephen; Geisow, Adrian; Rudin, John; Taphouse, Tim

2011-08-01

219

Bright color reflective displays with interlayer reflectors.  

PubMed

A good solution to the reflective display of color has been a major challenge for the display industry, with very limited color gamuts demonstrated to date. Conventional side-by-side red, green and blue color filters waste two-thirds of incident light. The alternative of stacking cyan, magenta and yellow layers is also challenging--a 10% loss per layer compounds to nearly 50% overall. Here we demonstrate an architecture that interleaves absorbing-to-clear shutters with matched wavelength selective reflectors. This increases color gamut by reducing losses and more cleanly separating the color channels, and gives much wider choice of electro-optic colorants. PMID:21934904

Kitson, Stephen; Geisow, Adrian; Rudin, John; Taphouse, Tim

2011-08-01

220

A new gene, bic, with pleiotropic effects (with T P V) for bicolor flowers and dark olive brown seed coat in common bean.  

Technology Transfer Automated Retrieval System (TEKTRAN)

‘Painted Lady’ (Phaseolus coccineus L.) has bicolor flowers with vermilion banner petal and white wing petals. This flower color pattern is not known in common bean (P. vulgaris L.). The bicolor trait was backcrossed into common bean and its inheritance was investigated, including allelism tests w...

221

 Cloning and expression of UDP-glucose: flavonoid 3-O-glucosyltransferase gene in peach flowers.  

PubMed

To elucidate the connection between flower coloration and the expression of genes associated with anthocyanin biosynthesis, a gene encoding UDP-glucose: flavonoid 3-O-glucosyltransferase (UFGT) was isolated, and the expression of the last four genes in the anthocyanin biosynthetic pathway during peach flower development was determined. The nucleotide sequence of the peach UFGT (GenBank accession No. JX149550) is highly similar to its homologs in other plants. Total anthocyanin content initially increased during peach flower development, and then decreased over time. Expression of the four anthocyanin biosynthesis genes increased until the full-bloom stage, and then decreased during late florescence. Expression of F3H, DFR, and UFGT increased dramatically at the full-bloom stage, coinciding with an increase in anthocyanin concentration. The UFGT gene may not be the only gene of the anthocyanin pathway to be differentially controlled in red peach flower tissues. Further studies are needed to genetically and physiologically characterize these genes and enzymes in peach flowers and to gain a better understanding of their functions and relationships with flower coloration. PMID:25501218

Wen, X C; Han, J; Leng, X P; Ma, R J; Jiang, W B; Fang, J G

2014-01-01

222

Color measurement and discrimination  

NASA Technical Reports Server (NTRS)

Theories of color measurement attempt to provide a quantative means for predicting whether two lights will be discriminable to an average observer. All color measurement theories can be characterized as follows: suppose lights a and b evoke responses from three color channels characterized as vectors, v(a) and v(b); the vector difference v(a) - v(b) corresponds to a set of channel responses that would be generated by some real light, call it *. According to theory a and b will be discriminable when * is detectable. A detailed development and test of the classic color measurement approach are reported. In the absence of a luminance component in the test stimuli, a and b, the theory holds well. In the presence of a luminance component, the theory is clearly false. When a luminance component is present discrimination judgements depend largely on whether the lights being discriminated fall in separate, categorical regions of color space. The results suggest that sensory estimation of surface color uses different methods, and the choice of method depends upon properties of the image. When there is significant luminance variation a categorical method is used, while in the absence of significant luminance variation judgments are continuous and consistant with the measurement approach.

Wandell, B. A.

1985-01-01

223

Synchronous Pulsed Flowering: Analysis of the Flowering Phenology in Juncus (Juncaceae)  

PubMed Central

Background and Aims The timing of flowering within and among individuals is of fundamental biological importance because of its influence on total seed production and, ultimately, fitness. Traditional descriptive parameters of flowering phenology focus on onset and duration of flowering and on synchrony among individuals. These parameters do not adequately account for variability in flowering across the flowering duration at individual and population level. This study aims to analyse the flowering phenology of wind-pollinated Juncus species that has been described as temporally highly variable (‘pulsed flowering’). Additionally, an attempt is made to identify proximate environmental factors that may cue the flowering, and ultimate causes for the flowering patterns are discussed. Methods Flowering phenology was examined in populations of nine Juncus species by estimating flowering synchrony and by using the coefficient of variation (CV) to describe the temporal variation in flowering on individual and population levels. Phenologies were compared with null models to test which patterns deviate from random flowering. All parameters assessed were compared with each other and the performance of the parameters in response to randomization and varying synchrony was evaluated using a model population. Flowering patterns were correlated with temperature and humidity. Key Results Most flowering patterns of Juncus were best described as synchronous pulsed flowering, characterized as population-wide concerted flowering events separated by days with no or few open flowers. Flowering synchrony and variability differed from a random pattern in most cases. CV values in combination with a measure of synchrony differentiated among flowering patterns found. Synchrony varied among species and was independent from variability in flowering. Neither temperature nor humidity could be determined as potential cues for the flowering pulses. Conclusions The results indicate that selection may act independently on synchrony and variability. We propose that synchronous pulsed flowering in Juncus is an evolved strategy that provides selective benefits by increasing outcrossing and by spreading the risk of reproductive failure. PMID:17881343

Michalski, Stefan G.; Durka, Walter

2007-01-01

224

Color notations  

E-print Network

This study presents research regarding the language of colors and of computers. The focus was color: translated through personal imagery, transferred and changed through media, and programmed through the computer. The ...

Gardner, Nancy

1981-01-01

225

186 DARWIN'S HERITAGE TODAY The Effects of Flower Color Transitions  

E-print Network

. Miller2 , Sarah P. Otto3,4 , Richard G. FitzJohn3,4 , Mark D. Rausher1 #12;187Stacey D. Smith et al 684-2295; Fax: 919 660- 7293; E-mail: mrausher@duke.edu Mark D. Rausher Stacey D. Smith1 , Richard E. About Author Stacey D. Smith is a postdoctoral fellow in the Department of Biology at Duke Univer- sity

Rausher, Mark D.

226

Color image segmentation approach to monitor flowering in lesquerella  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lesquerella (Lesquerella fendleri) seed soil has been proposed as a petroleum alternative in the production of many industrial products, but several crop management and breeding challenges must be addressed before the crop will be grown commercially. Lesquerella canopies characteristically exhibit ...

227

Wild bees preferentially visit Rudbeckia flower heads with exaggerated ultraviolet absorbing floral guides  

PubMed Central

ABSTRACT Here, we report on the results of an experimental study that assessed the visitation frequency of wild bees to conspecific flowers with different sized floral guides. UV absorbent floral guides are ubiquitous in Angiosperms, yet surprisingly little is known about conspecific variation in these guides and very few studies have evaluated pollinator response to UV guide manipulation. This is true despite our rich understanding about learning and color preferences in bees. Historical dogma indicates that flower color serves as an important long-range visual signal allowing pollinators to detect the flowers, while floral guides function as close-range signals that direct pollinators to a reward. We initiated the work presented here by first assessing the population level variation in UV absorbent floral guides for conspecific flowers. We assessed two species, Rudbeckia hirta and R. fulgida. We then used several petal cut-and-paste experiments to test whether UV floral guides can also function to attract visitors. We manipulated floral guide size and evaluated visitation frequency. In all experiments, pollinator visitation rates were clearly associated with floral guide size. Diminished floral guides recruited relatively few insect visitors. Exaggerated floral guides recruited more visitors than smaller or average sized guides. Thus, UV floral guides play an important role in pollinator recruitment and in determining the relative attractiveness of conspecific flower heads. Consideration of floral guides is therefore important when evaluating the overall conspicuousness of flower heads relative to background coloration. This work raises the issue of whether floral guides serve as honest indicators of reward, since guide size varies in nature for conspecific flowers at the same developmental stage and since preferences for larger guides were found. To our knowledge, these are the first cut-and-paste experiments conducted to examine whether UV absorbent floral guides affect visitation rates and pollinator preference. PMID:24585774

Horth, Lisa; Campbell, Laura; Bray, Rebecca

2014-01-01

228

Transcriptome Analysis of Differentially Expressed Genes Relevant to Variegation in Peach Flowers  

PubMed Central

Background Variegation in flower color is commonly observed in many plant species and also occurs on ornamental peaches (Prunus persica f. versicolor [Sieb.] Voss). Variegated plants are highly valuable in the floricultural market. To gain a global perspective on genes differentially expressed in variegated peach flowers, we performed large-scale transcriptome sequencing of white and red petals separately collected from a variegated peach tree. Results A total of 1,556,597 high-quality reads were obtained, with an average read length of 445 bp. The ESTs were assembled into 16,530 contigs and 42,050 singletons. The resulting unigenes covered about 60% of total predicted genes in the peach genome. These unigenes were further subjected to functional annotation and biochemical pathway analysis. Digital expression analysis identified a total of 514 genes differentially expressed between red and white flower petals. Since peach flower coloration is determined by the expression and regulation of structural genes relevant to flavonoid biosynthesis, a detailed examination detected four key structural genes, including C4H, CHS, CHI and F3H, expressed at a significantly higher level in red than in white petal. Except for the structural genes, we also detected 11 differentially expressed regulatory genes relating to flavonoid biosynthesis. Using the differentially expressed structural genes as the test objects, we validated the digital expression results by using quantitative real-time PCR, and the differential expression of C4H, CHS and F3H were confirmed. Conclusion In this study, we generated a large EST collection from flower petals of a variegated peach. By digital expression analysis, we identified an informative list of candidate genes associated with variegation in peach flowers, which offered a unique opportunity to uncover the genetic mechanisms underlying flower color variegation. PMID:24603808

Yu, Faxin; Li, Shuxian; Yin, Tongming

2014-01-01

229

Seeing Color  

ERIC Educational Resources Information Center

Colors are powerful tools for engaging children, from the youngest years onward. We hang brightly patterned mobiles above their cribs and help them learn the names of colors as they begin to record their own ideas in pictures and words. Colors can also open the door to an invisible world of electromagnetism, even when children can barely imagine…

Texley, Juliana

2005-01-01

230

Anatomical and biochemical studies of bicolored flower development in Muscari latifolium.  

PubMed

The inflorescence of the broad-leafed grape hyacinth, Muscari latifolium, shows an interesting, two-tone appearance with the upper flowers being pale blue and the lower ones purple. To elucidate the mechanism of the differential color development, anatomical research was carried out and a cytological study of the colored protoplasts in which the shapes of the cells accumulating anthocyanin were observed by scanning electron microscopy. Next, vacuolar pH was recorded using a pH meter with a micro combination pH electrode, and the sap's metal-ion content was measured by inductively coupled plasma mass spectrometry. The anthocyanin and co-pigment composition was determined by high-performance liquid chromatography (HPLC). Chemical analyses reveal that the difference in metal-ion content of the two parts was not great. The vacuolar pHs of the upper and lower flowers were 5.91 and 5.84, respectively, with the difference being nonsignificant. HPLC results indicate that the dihydroflavonol and flavonol contents are also very similar in the two sorts of flower. However, the upper flowers contained only delphinidin, whereas the lower flowers also contained cyanidin. The total anthocyanin content in the lower flowers was 4.36 mg g(-1), which is approximately seven times higher than in the upper flowers, while the delphinidin content is four times higher. Quantitative real-time PCR analysis established that the two-tone flower was a result of different expressions of the F3'5'H, F3'H and DFR genes, and these lead to different amounts of anthocyanin. PMID:23677687

Qi, Yinyan; Lou, Qian; Li, Huibo; Yue, Juan; Liu, Yali; Wang, Yuejin

2013-12-01

231

The Preference for Symmetry in Flower-Naive and Not-so-Naive Bumblebees  

ERIC Educational Resources Information Center

Truly flower-naive bumblebees, with no prior rewarded experience for visits on any visual patterns outside the colony, were tested for their choice of bilaterally symmetric over asymmetric patterns in a radial-arm maze. No preference for symmetry was found. Prior training with rewarded black and white disks did, however, lead to a significant…

Plowright, C. M. S.; Evans, S. A.; Leung, J. Chew; Collin, C. A.

2011-01-01

232

How Bumblebees First Find Flowers: Habituation of Visual Pattern Preferences, Spontaneous Recovery, and Dishabituation  

ERIC Educational Resources Information Center

Two experiments examined the exploratory behaviour of flower-naive bumblebees. Bees were tested four times in a 12-arm radial arm maze in which they never received reward. Patterned and unpatterned stimuli were presented at the end of each corridor and the choices of the bees were recorded. We examined the effects of two variables, time and the…

Plowright, C. M. S.; Simonds, V. M.; Butler, M. A.

2006-01-01

233

Color Quiz  

NSDL National Science Digital Library

Please take this Quiz. It is not that hard. Remember If you understand color, you will be able to use color in your artwork more effectively. For your Quiz please answer the 18 questions below. Here are some sites you have already seen that will help you answer the questions. Color Theory Color Vocabulary Wikipedia color theory You may write your answers down on a piece of paper or you can type the answers up. Make sure name, period, and date are on assignment ...

Ms. Freeman

2006-02-14

234

Color Quiz  

NSDL National Science Digital Library

Please take this Quiz. It is not that hard. Remember If you understand color, you will be able to use color in your artwork more effectively. For your Quiz please answer the 18 questions below. Here are some sites you have already seen that will help you answer the questions. Color Theory Color Vocabulary Wikipedia color theory You may write your answers down on a piece of paper or you can type the answers up. Make sure name, period, and date are on assignment ...

JoLene

2008-09-29

235

Inflorescence and flower development in the Hedychieae (Zingiberaceae): Hedychium  

E-print Network

Inflorescence and flower development in the Hedychieae (Zingiberaceae): Hedychium Bruce K. Kirchoff flower. Key words: flower development, flower structure, inflorescence, stamen, Zingiberaceae, structure de la fleur, inflorescence, Ctamine, Zingiberaceae, Hedychium. [Traduit par la ridaction

Kirchoff, Bruce K.

236

Bee getting nectar from a lavender flower  

NSDL National Science Digital Library

The bee obtains nectar to take to the beehive where it is used to make honey and provide food for the bees. The bee grabs pollen and transfers it to other flowers. This is called pollination and helps flowers reproduce.

Katie Hale (California State University, Fullerton; Student, Biological Sciences)

2006-12-30

237

The structure of choice  

Microsoft Academic Search

Both J. A. Nevin (ses PA, Vol 44:4827) and C. P. Shimp found on different choice procedures that pigeons equate (match) the proportion of their choices to the proportion of reinforcers each choice delivers. Their results differed in terms of the order of successive choices: Shimp found that pigeons ordered successive choices so as to maximize the reinforcement rate, whereas

Alan Silberberg; Bruce Hamilton; John M. Ziriax; Jay Casey

1978-01-01

238

Color Categories and Color Appearance  

ERIC Educational Resources Information Center

We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

Webster, Michael A.; Kay, Paul

2012-01-01

239

Crosstalk between Cold Response and Flowering in Arabidopsis Is Mediated through the Flowering-Time Gene  

E-print Network

Crosstalk between Cold Response and Flowering in Arabidopsis Is Mediated through the Flowering-Gu, Gwangju, 500-757, Korea c Global Research Laboratory for Flowering at Seoul National University University, Suwon 449-701, Korea The appropriate timing of flowering is pivotal for reproductive success

Lee, Ilha

240

Role of FRIGIDA and FLOWERING LOCUS C in Determining Variation in Flowering Time  

E-print Network

Role of FRIGIDA and FLOWERING LOCUS C in Determining Variation in Flowering Time of Arabidopsis1[w collected to represent worldwide and local variation and analyzed two adaptively important traits, flowering time and vernalization response. There was huge variation in the flowering habit of the different

Howard, Martin

241

A latitudinal cline in flowering time in Arabidopsis thaliana modulated by the flowering time  

E-print Network

A latitudinal cline in flowering time in Arabidopsis thaliana modulated by the flowering time gene, and approved January 6, 2004 (received for review October 4, 2003) A latitudinal cline in flowering time flowering vary systematically with latitude, but evidence for such clines has been lacking. Here, we report

Purugganan, Michael D.

242

Acceleration of Flowering during Shade Avoidance in Arabidopsis Alters the Balance between FLOWERING  

E-print Network

Acceleration of Flowering during Shade Avoidance in Arabidopsis Alters the Balance between FLOWERING LOCUS C-Mediated Repression and Photoperiodic Induction of Flowering1[W][OA] Amanda C. Wollenberg of flowering in response to vegetative shade, a condition that is perceived as a decrease in the ratio of red

Raines, Ronald T.

243

FLOBOTS: ROBOTIC FLOWERS FOR BEE BEHAVIOUR EXPERIMENTS  

PubMed Central

Studies of pollinator foraging behaviour often require artificial flowers that can refill themselves, allowing pollinators to forage for long periods of time under experimental conditions. Here I describe a design for inexpensive flowers that can refill themselves upon demand and that are easy enough to set up and clean that they can be used in arrays of 30 or more flowers. I also summarize of a variety of artificial flower designs developed by other researchers. PMID:25722755

Essenberg, Carla J.

2015-01-01

244

Rufous hummingbirds' memory for flower location  

Microsoft Academic Search

We used an open-field analogue of the eight-arm radial maze to investigate the role of memory during foraging by rufous hummingbirds, Selasphorus rufus. In experiment 1 we attempted to determine whether birds were able to differentiate between flowers of the same type that they had emptied, flowers they had seen but not visited and new flowers. They were tested with

Jonathan Henderson; T. Andrew Hurly; Susan D. Healy

2001-01-01

245

CSULB ALUMNI ASSOCIATION Commencement Flowers Sale 2014  

E-print Network

CSULB ALUMNI ASSOCIATION Commencement Flowers Sale 2014 VOLUNTEER REPLY FORM Please check the days and shifts you can help. We may release volunteers early based upon need. Due to the swift pace of flower a shorter shift you may leave early, but please do not arrive late. + Commencement Flower Sales may entail

Sorin, Eric J.

246

Fooling Mother Nature: Forcing Flower Bulbs  

E-print Network

Fooling Mother Nature: Forcing Flower Bulbs for Indoor Bloom by George Graine,Virginia Cooperative of Horticulture, Virginia Tech, Blacksburg, VA Publication HORT-76NP #12;Fooling Mother Nature: Forcing Flower. Regardless, all of these bulbs have one thing in common that separates them from other flowering annual

Liskiewicz, Maciej

247

Developmental Cell Flower Morphogenesis: Timing Is Key  

E-print Network

Developmental Cell Previews Flower Morphogenesis: Timing Is Key Doris Wagner1,* 1Department@sas.upenn.edu DOI 10.1016/j.devcel.2009.05.005 Flowers are unique parts of plants because they form a predictable al. reveal that timing of the onset of flower differentiation is key for the stereotypic architecture

Plotkin, Joshua B.

248

6, 1105111066, 2006 Sea ice, frost flowers  

E-print Network

ACPD 6, 11051­11066, 2006 Sea ice, frost flowers and halogen activation W. R. Simpson et al. Title than potential frost flower contact W. R. Simpson 1 , D. Carlson 1 , G. Hoenninger 1,2, , T. A. Douglas. Simpson (ffwrs@uaf.edu) 11051 #12;ACPD 6, 11051­11066, 2006 Sea ice, frost flowers and halogen activation

Paris-Sud XI, Université de

249

SEMI-FLOWER AUTOMATA SHUBH NARAYAN SINGH  

E-print Network

SEMI-FLOWER AUTOMATA SHUBH NARAYAN SINGH DEPARTMENT OF MATHEMATICS INDIAN INSTITUTE OF TECHNOLOGY GUWAHATI GUWAHATI - 781039, INDIA AUGUST 2012 #12;#12;Semi-Flower Automata By Shubh Narayan Singh;#12;Certificate This is to certify that the thesis entitled Semi-Flower Automata submitted by Mr. Shubh Narayan

Krishna, Kanduru V.

250

Processing of Color Words Activates Color Representations  

ERIC Educational Resources Information Center

Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

Richter, Tobias; Zwaan, Rolf A.

2009-01-01

251

Pyrethrum flowers and pyrethroid insecticides.  

PubMed Central

The natural pyrethrins from the daisy-like flower, Tanacetum or Chrysanthemum cinerariifolium, are nonpersistent insecticides of low toxicity to mammals. Synthetic analogs or pyrethroids, evolved from the natural compounds by successive isosteric modifications, are more potent and stable and are the newest important class of crop protection chemicals. They retain many of the favorable properties of the pyrethrins. PMID:6993201

Casida, J E

1980-01-01

252

A Flower of Tibouchina semidecandra,  

NSDL National Science Digital Library

A flower of Tibouchina semidecandra, a well-known ornamental from southeastern Brazil. Tibouchinais a member of the large tropical family Melastomataceae and together with other Melastomeae has been regarded as representing a relatively basal element of the family. Molecular evidence suggests that Tibouchina, Melastoma, Osbeckia, and other Melastomeae represent a derived clade of Melastomataceae that only recently reached Africa and tropical Asia.

Susanne Renner (University of Missouri-St. Louis; Department of Biology ADR; POSTAL)

2004-03-09

253

Color Analysis  

NASA Astrophysics Data System (ADS)

Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

Wrolstad, Ronald E.; Smith, Daniel E.

254

Ability of Bumblebees to Discriminate Differences in the Shape of Artificial Flowers of Primula sieboldii (Primulaceae)  

PubMed Central

Background and Aims Flower shapes are important visual cues for pollinators. However, the ability of pollinators to discriminate between flower shapes under natural conditions is poorly understood. This study focused on the diversity of flower shape in Primula sieboldii and investigated the ability of bumblebees to discriminate between flowers by combining computer graphics with a traditional behavioural experiment. Methods Elliptic Fourier descriptors described shapes by transforming coordinate information for the contours into coefficients, and principal components analysis summarized these coefficients. Using these methods, artificial flowers were created based on the natural diversity of petal shape in P. sieboldii. Dual-choice tests were then performed to investigate the ability of the bumblebees to detect differences in the aspect ratio of petals and the depth of their head notch. Key Results The insects showed no significant ability to detect differences in the aspect ratio of the petals under natural conditions unless the morphological distance increased to an unrealistic level. These results suggest the existence of a perception threshold for distances in this parameter. The bumblebees showed a significant preference for narrow petals even after training using flowers with wide petals. The bumblebees showed a significant ability to discriminate based on the depth of the petal head notch after training using artificial flowers with a deep head notch. However, they showed no discrimination in tests with training using extreme distances between flowers in this parameter. Conclusions A new type of behavioural experiment was demonstrated using real variation in flower corolla shape in P. sieboldii. If the range in aspect ratios of petals expands much further, bumblebees may learn to exhibit selective behaviour. However, because discrimination by bumblebees under natural conditions was low, there may be no strong selective behaviour based on innate or learned preferences under natural conditions. PMID:17553825

Yoshioka, Yosuke; Ohashi, Kazuharu; Konuma, Akihiro; Iwata, Hiroyoshi; Ohsawa, Ryo; Ninomiya, Seishi

2007-01-01

255

Color categories and color appearance.  

PubMed

We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary were perceptually exaggerated. This task did not require overt judgments of the perceived colors, and the tendency to group showed only a weak and inconsistent categorical bias. In a second case, we analyzed results from two prior studies of hue scaling of chromatic stimuli (De Valois, De Valois, Switkes, & Mahon, 1997; Malkoc, Kay, & Webster, 2005), to test whether color appearance changed more rapidly around the blue-green boundary. In this task observers directly judge the perceived color of the stimuli and these judgments tended to show much stronger categorical effects. The differences between these tasks could arise either because different signals mediate color grouping and color appearance, or because linguistic categories might differentially intrude on the response to color and/or on the perception of color. Our results suggest that the interaction between language and color processing may be highly dependent on the specific task and cognitive demands and strategies of the observer, and also highlight pronounced individual differences in the tendency to exhibit categorical responses. PMID:22176751

Webster, Michael A; Kay, Paul

2012-03-01

256

Preference for oddity: uniqueness heuristic or hierarchical choice process?  

Microsoft Academic Search

Traditional economic theories assume decision makers in multialternative choice tasks “assign” a value to each option and\\u000a then express rational preferences. Here, I report an apparent violation of such rationality in gray jays (Perisoreus canadensis). I tested the jays’ preference in a quaternary choice task where three options were the same color and the fourth option\\u000a was a different color.

Thomas A. Waite

2008-01-01

257

Difference in flowering time can initiate speciation of nocturnally flowering species.  

PubMed

Isolation mechanisms that prevent gene flow between populations prezygotically play important roles in achieving speciation. In flowering plants, the nighttime flowering system provides a mechanism for isolation from diurnally flowering species. Although this system has long been of interest in evolutionary biology, the evolutionary process leading to this system has yet to be elucidated because of the lack of good model species. However, the genetic mechanisms underlying the differences in flowering times and the traits that attract pollinators between a pair of diurnally and nocturnally flowering species have recently been identified in a few cases. This identification enables us to build a realistic model for theoretically studying the evolution of a nocturnally flowering species. In this study, based on previous experimental data, we assumed a model in which two loci control the flowering time and one locus determines a trait that attracts pollinators. Using this model, we evaluated the possibility of the evolution of a nocturnally flowering species from a diurnally flowering ancestor through simulations. We found that a newly emerging nighttime flowering flower exhibited a sufficiently high fitness, and the evolution of a nocturnally flowering species from a diurnally flowering species could be achieved when hybrid viability was intermediate to low, even in a completely sympatric situation. Our results suggest that the difference in flowering time can act as a magic trait that induces both natural selection and assortative mating and would play an important role in speciation between diurnally and nocturnally flowering species pairs. PMID:25665720

Matsumoto, Tomotaka; Yasumoto, Akiko A; Nitta, Kozue; Hirota, Shun K; Yahara, Tetsukazu; Tachida, Hidenori

2015-04-01

258

Flower scent composition in night-flowering Silene species (Caryophyllaceae)  

Microsoft Academic Search

Floral scent of 13 night-flowering Silene species (Caryophyllaceae) was collected by headspace adsorption and analysed via gas chromatography and mass spectrometry. Benzenoids together with isoprenoids dominated the scent in all species. Among the benzenoids, benzaldehyde (Silene subconica 35.5%, Silene succulenta 23.1%, Silene sericea 15.6%, Silene vulgaris 12.2%, and Silene nutans 9.9%), methylbenzoate (Silene saxifraga 96.1%, S. succulenta 15.2%), benzyl acetate

A. Jürgens; T. Witt; G. Gottsberger

2002-01-01

259

Sampling flower scent for chromatographic analysis.  

PubMed

The analysis of flower volatiles requires special methods for their isolation with enrichment. Living flowers show a continuous change in their volatile profile that depends on intrinsic (genetic) and external (light, temperature, hydric stress) factors. Excised flowers suffer rapid deterioration and loss of volatiles. While industrial isolation methods for flower volatiles are well established, those at the laboratory-scale experience progressive development, in the search for higher sensitivity, reproducibility, and simplicity. This review covers the flower scent sampling methods most commonly employed during the last decade, and includes comments on their strengths and limitations. The strengths of headspace solid-phase microextraction (HS-SPME) for in vivo monitoring are emphasized with the examples of monitoring the circadian variation of Brugmansia suaveolens flower scent and of volatile aldehyde detection in flower scent using on-fiber derivatization. PMID:18618804

Stashenko, Elena E; Martínez, Jairo René

2008-06-01

260

Intitial progress report to the International Cut Flower Growers Association Development of protocols for optimization of branching and flower counts in cut-flower gerbera  

E-print Network

Intitial progress report to the International Cut Flower Growers Association Development of protocols for optimization of branching and flower counts in cut-flower gerbera production Heiner Lieth August 31, 2006 Gerbera growers typically see a seasonal decline in flower yield (number of flowers per

Lieth, J. Heinrich

261

Effects of shade on plant growth and flower quality in the herbaceous peony (Paeonia lactiflora Pall.).  

PubMed

Herbaceous peony (Paeonia lactiflora Pall.) is an important ornamental plant used in urban green spaces, but little is known about whether it can grow in a shaded environment or understory. In this study, effects of shade on plant growth and flower quality in the herbaceous peony were investigated. The results showed that P. lactiflora morphology parameters, including plant height, leaf number, stem diameter, branch number, node number and plant crown width, were higher in plants grown with sun exposure compared to those grown in shade; however, opposite trends were observed for the top and middle leaf areas of the plant. Compared with sun exposure, shade decreased P. lactiflora photosynthetic capacity, light saturation point (LSP) and light compensation point (LCP) and increased the apparent quantum yield (AQY), mainly due to declined stomatal conduction (Gs). These decreases caused the soluble sugar, soluble protein and malondialdehyde (MDA) contents to decline, which led to delayed initial flowering date, prolonged flowering time, reduced flower fresh weight, increased flower diameter and faded flower color. Through cloning and expression analysis of anthocyanin biosynthetic genes, we determined that the fading of flower color was the result of reduced anthocyanin content, which was caused by the combined activity of anthocyanin biosynthesis genes and, in particular, of the upstream phenylalanine ammonialyase gene (PlPAL) and chalcone synthase gene (PlCHS). These results could provide us with a theoretical basis for further application of P. lactiflora in the greening of urban spaces and an understanding of the mechanisms behind the changes induced by shade. PMID:23141672

Zhao, Daqiu; Hao, Zhaojun; Tao, Jun

2012-12-01

262

Catching ants with honey: an experimental test of distraction and satiation as alternative modes of escape from flower-damaging ants.  

PubMed

According to the distraction hypothesis, extrafloral nectaries (EFN) evolved under selection to entice ants away from floral nectaries, reducing ant-mediated damage to flowers and/or interference with pollinators. Predator-satiation, through production of nectar in either surplus flowers or EFN, provides an alternative mechanism for reducing the impact of ants as flower visitors. I tested these two hypotheses by experimentally adding EFN to flowering plants of the alpine wildflower, Polemonium viscosum, and by surveying the relationship between ant visitation and nectary number in nature. Plants of P. viscosum lack EFN and experience flower damage by ants of Formica neorufibarbus gelida. Ant behavior was compared on plants with five flowers and three experimental EFN and on controls with equal floral display, but no EFN. Addition of EFN increased flower visitation by ants. The effect of EFN on flower visitation did not depend on proximity of EFN to flowers or attractiveness of EFN to ants. Findings suggest that ants perceived patch quality on a whole plant basis, rather than responding to EFN and flowers as distinct nectar patches. Ant visitation did not keep pace with nectary number in nature. The relationship between ant visitation and nectary number per plant was weak and shallow as predicted under satiation. Ant foraging choices on experimental inflorescences showed that ants bypass flowers avoided by earlier ants, enhancing probability of escape via satiation. Results do not support the idea that EFN evolve to reduce flower visitation by ants, but show instead that nectar in surplus flowers can satiate ants and reduce their negative impacts on flower function and integrity. PMID:15800742

Galen, Candace

2005-06-01

263

Homelessness as a Choice  

Microsoft Academic Search

It has long been assumed that homelessness is a personal choice. As a choice, homelessness is embedded within debates about deviant behaviours and problematic pathologies. The “homeless person” is either making calculated and immoral choices to be homeless, or they are perceived to be powerless agents who lack the capacity to exercise choices. Rarely has it been adequately explained, however,

Cameron Parsell; Mitch Parsell

2012-01-01

264

Color Lines.  

ERIC Educational Resources Information Center

Teaching about color and value scales emphasizes a systematic approach to the effects of color and may reinforce assumptions rooted in racism. Describes how an 8th grade art class challenged the symbolism of black as evil and white as good. By showing that this is a culturally constructed meaning, art teachers model that such meaning can also be…

Gude, Olivia

2001-01-01

265

Early flower development in Arabidopsis.  

PubMed Central

The early development of the flower of Arabidopsis thaliana is described from initiation until the opening of the bud. The morphogenesis, growth rate, and surface structure of floral organs were recorded in detail using scanning electron microscopy. Flower development has been divided into 12 stages using a series of landmark events. Stage 1 begins with the initiation of a floral buttress on the flank of the apical meristem. Stage 2 commences when the flower primordium becomes separate from the meristem. Sepal primordia then arise (stage 3) and grow to overlie the primordium (stage 4). Petal and stamen primordia appear next (stage 5) and are soon enclosed by the sepals (stage 6). During stage 6, petal primordia grow slowly, whereas stamen primordia enlarge more rapidly. Stage 7 begins when the medial stamens become stalked. These soon develop locules (stage 8). A long stage 9 then commences with the petal primordia becoming stalked. During this stage all organs lengthen rapidly. This includes the gynoecium, which commences growth as an open-ended tube during stage 6. When the petals reach the length of the lateral stamens, stage 10 begins. Stigmatic papillae appear soon after (stage 11), and the petals rapidly reach the height of the medial stamens (stage 12). This final stage ends when the 1-millimeter-long bud opens. Under our growing conditions 1.9 buds were initiated per day on average, and they took 13.25 days to progress through the 12 stages from initiation until opening. PMID:2152125

Smyth, D R; Bowman, J L; Meyerowitz, E M

1990-01-01

266

Flower colour adaptation in a mimetic orchid  

PubMed Central

Although the tremendous variability in floral colour among angiosperms is often attributed to divergent selection by pollinators, it is usually difficult to preclude the possibility that floral colour shifts were driven by non-pollinator processes. Here, we examine the adaptive significance of flower colour in Disa ferruginea, a non-rewarding orchid that is thought to attract its butterfly pollinator by mimicking the flowers of sympatric nectar-producing species. Disa ferruginea has red flowers in the western part of its range and orange flowers in the eastern part—a colour shift that we hypothesized to be the outcome of selection for resemblance to different local nectar-producing plants. Using reciprocal translocations of red and orange phenotypes as well as arrays of artificial flowers, we found that the butterfly Aeropetes tulbaghia, the only pollinator of the orchid, preferred both the red phenotype and red artificial flowers in the west where its main nectar plant also has red flowers, and both the orange phenotype and orange artificial flowers in the east, where its main nectar plant has orange flowers. This phenotype by environment interaction demonstrates that the flower colour shift in D. ferruginea is adaptive and driven by local colour preference in its pollinator. PMID:22298842

Newman, Ethan; Anderson, Bruce; Johnson, Steven D.

2012-01-01

267

Color appearance in stereoscopy  

NASA Astrophysics Data System (ADS)

The relationship between color and lightness appearance and the perception of depth has been studied since a while in the field of perceptual psychology and psycho-physiology. It has been found that depth perception affects the final object color and lightness appearance. In the stereoscopy research field, many studies have been proposed on human physiological effects, considering e.g. geometry, motion sickness, etc., but few has been done considering lightness and color information. Goal of this paper is to realize some preliminar experiments in Virtual Reality in order to determine the effects of depth perception on object color and lightness appearance. We have created a virtual test scene with a simple 3D simultaneous contrast configuration. We have created three different versions of this scene, each with different choices of relative positions and apparent size of the objects. We have collected the perceptual responses of several users after the observation of the test scene in the Virtual Theater of the University of Milan, a VR immersive installation characterized by a semi-cylindrical screen that covers 120° of horizontal field of view from an observation distance of 3.5 m. We present a description of the experiments setup and procedure, and we discuss the obtained results.

Gadia, Davide; Rizzi, Alessandro; Bonanomi, Cristian; Marini, Daniele; Galmonte, Alessandra; Agostini, Tiziano

2011-03-01

268

Effect of glucuronosylation on anthocyanin color stability.  

PubMed

The effect of glucuronosylation on the color stability of anthocyanins was investigated using glucuronosylated anthocyanins isolated from the flower petals of the red daisy (Bellis perennis) or obtained by enzymatic in vitro synthesis using heterologously expressed red daisy glucuronosyltransferase BpUGT94B1. Color stability toward light and heat stress was assessed by monitoring CIELAB color coordinates and stability at pH 7.0 by A(550). Cyanidin-3-O-2''-O-glucuronosylglucoside showed improved color stability in response to light compared to both cyanidin 3-O-glucoside and cyanidin 3-O-2''-O-diglucoside. A similar increase in color stability was not observed following heat treatment. Glucuronosylation did not increase the stability of anthocyanins at pH 7.0 as determined by A(550). To test for a possible effect of glucuronosylation on the color stability of anthocyanins in plant extracts used for food coloration, an elderberry (Sambucus nigra) extract was glucuronosylated in vitro. Glucuronosylation of approximately 50% of total anthocyanins proceeded fast and resulted in increased color stability in response to both heat and light. The data show that glucuronosylation may be used to stabilize industrially used extracts of natural colorants. PMID:19281238

Osmani, Sarah Anne; Hansen, Esben Halkjaer; Malien-Aubert, Céline; Olsen, Carl-Erik; Bak, Sřren; Mřller, Birger Lindberg

2009-04-22

269

Color Me Safe Coloring Book  

MedlinePLUS

... Me Safe is a coloring book designed for children ages four to seven. Throughout the book, the Safe Family takes simple steps to prevent injuries, such as installing smoke alarms and using child safety seats. Children can have fun coloring the pictures and reading ...

270

Influence of Riparian Tree Phenology on Lower Colorado River Spring-Migrating Birds: Implications of Flower Cueing  

USGS Publications Warehouse

Executive Summary Neotropical migrant birds make choices about which habitats are most likely to provide successful foraging locations during migration, but little is known about how these birds recognize and process environmental clues that indicate the presence of prey species. Aspects of tree phenology, notably flowering of trees along the lower Colorado River corridor, coincide with the migratory stopovers of leaf-gleaning insectivorous songbirds and may be an important indicator of arthropod prey species availability. Shifting tree flowering and leaf flush during the spring migration period presents avian insectivores with an assortment of foraging opportunities. During two field seasons at Cibola National Wildlife Refuge in southwestern Arizona, we examined riparian tree species to test whether leaf-gleaning insectivorous birds are attracted to the flowering condition of trees in choosing foraging sites. We predicted that flowering trees would host more insect prey resources, would thus show increased visit rates, length of stays and attack ratios of migrant avian insectivores, and that those arthropods would be found in the stomach contents of the birds. Paired trees of honey mesquite (Prosopis glandulosa), displaying heavy and light degrees of flowering were observed to test these predictions. To test whether birds are tracking arthropods directly or are using flowers as a proximate cue, we removed flowers from selected trees and paired these treated trees with neighboring high flowering trees, which served as controls. Avian foraging behavior, avian diets, arthropods, and phenology data were collected at the same time to control for temporal differences in insect availability, plant phenology, and differences in stopover arrivals of birds. We documented five patterns from this study: 1) Higher abundance and richness of arthropods were found on honey mesquite trees with greater numbers of flowers. 2) Arthropod abundance and richness increased as flowering level increased. 3) The subset of migrant avian insectivores selected for study disproportionately foraged among honey mesquite trees with significantly greater amounts of flower coverage than they did on trees with less than average flower coverage. 4) Paired field experiments demonstrated that migrant avian insectivores more often visited, stayed longer, and had higher attack rates on insect prey in honey mesquite trees with greater numbers of flowers. 5) Diet analyses of selected avian insectivores showed over half of their diet consisted of prey significantly associated with honey mesquite flowering. Combined, these results suggest that honey mesquite flowering condition is an important cue used by avian insectivores that enables birds to quickly find arthropod prey at stop-over locations, while in transit during spring migration.

McGrath, Laura J.; van Riper, Charles, III

2005-01-01

271

EARLY FLOWERING3 Regulates Flowering in Spring Barley by Mediating Gibberellin Production and FLOWERING LOCUS T Expression.  

PubMed

EARLY FLOWERING3 (ELF3) is a circadian clock gene that contributes to photoperiod-dependent flowering in plants, with loss-of-function mutants in barley (Hordeum vulgare), legumes, and Arabidopsis thaliana flowering early under noninductive short-day (SD) photoperiods. The barley elf3 mutant displays increased expression of FLOWERING LOCUS T1 (FT1); however, it remains unclear whether this is the only factor responsible for the early flowering phenotype. We show that the early flowering and vegetative growth phenotypes of the barley elf3 mutant are strongly dependent on gibberellin (GA) biosynthesis. Expression of the central GA biosynthesis gene, GA20oxidase2, and production of the bioactive GA, GA1, were significantly increased in elf3 leaves under SDs, relative to the wild type. Inhibition of GA biosynthesis suppressed the early flowering of elf3 under SDs independently of FT1 and was associated with altered expression of floral identity genes at the developing apex. GA is also required for normal flowering of spring barley under inductive photoperiods, with chemical and genetic attenuation of the GA biosynthesis and signaling pathways suppressing inflorescence development under long-day conditions. These findings illustrate that GA is an important floral promoting signal in barley and that ELF3 suppresses flowering under noninductive photoperiods by blocking GA production and FT1 expression. PMID:24781117

Boden, Scott A; Weiss, David; Ross, John J; Davies, Noel W; Trevaskis, Ben; Chandler, Peter M; Swain, Steve M

2014-04-29

272

EARLY FLOWERING3 Regulates Flowering in Spring Barley by Mediating Gibberellin Production and FLOWERING LOCUS T Expression[C][W  

PubMed Central

EARLY FLOWERING3 (ELF3) is a circadian clock gene that contributes to photoperiod-dependent flowering in plants, with loss-of-function mutants in barley (Hordeum vulgare), legumes, and Arabidopsis thaliana flowering early under noninductive short-day (SD) photoperiods. The barley elf3 mutant displays increased expression of FLOWERING LOCUS T1 (FT1); however, it remains unclear whether this is the only factor responsible for the early flowering phenotype. We show that the early flowering and vegetative growth phenotypes of the barley elf3 mutant are strongly dependent on gibberellin (GA) biosynthesis. Expression of the central GA biosynthesis gene, GA20oxidase2, and production of the bioactive GA, GA1, were significantly increased in elf3 leaves under SDs, relative to the wild type. Inhibition of GA biosynthesis suppressed the early flowering of elf3 under SDs independently of FT1 and was associated with altered expression of floral identity genes at the developing apex. GA is also required for normal flowering of spring barley under inductive photoperiods, with chemical and genetic attenuation of the GA biosynthesis and signaling pathways suppressing inflorescence development under long-day conditions. These findings illustrate that GA is an important floral promoting signal in barley and that ELF3 suppresses flowering under noninductive photoperiods by blocking GA production and FT1 expression. PMID:24781117

Boden, Scott A.; Weiss, David; Ross, John J.; Davies, Noel W.; Trevaskis, Ben; Chandler, Peter M.; Swain, Steve M.

2014-01-01

273

Choosing Choice: School Choice in International Perspective.  

ERIC Educational Resources Information Center

The chapters in this book originated as papers for a conference, School Choice and Educational Change, held in March 2000 at Michigan State University. An introductory chapter provides a comparative analysis of the lessons learned from international experience with school-choice policies, based on a review of case studies in several countries. The…

Plank, David N., Ed.; Sykes, Gary, Ed.

274

Color Sudoku  

NSDL National Science Digital Library

The popular sudoku puzzles use numbers, but the game could played with any set of 9 different objects! In this activity (on pages 56-75 of PDF), learners use objects of different colors (marbles, paper squares, candies) to solve sudoku puzzles. Learners use logic to determine where all the colored objects go, given the different colors already present on the puzzles. The activity includes suggestions for how to approach the game, 10 puzzles of varying size and difficulty, and links to websites with many more puzzles.

2014-10-22

275

Changing Colors  

NSDL National Science Digital Library

In this challenge, learners have to figure out in what order to combine five solutions to change the color from clear, to yellow, to blue, and back to clear. The five chemicals are potassium iodide, sodium thiosulfate, sodium hypochlorite (Clorox bleach), soluble starch (Niagara spray starch), and water. The color changes indicate chemical reactions, and the lesson includes some background information about the reactions that create different colors. Suggestions are given for guiding learners through systematic approaches to making the different combinations and observing the results, and for explaining to different age groups what happens when the solutions are combined.

Sciencenter

2014-08-27

276

Color Theory  

NSDL National Science Digital Library

This Web site, developed by the Exploratories Project at Brown University, provides a series of applets to help users understand the various concepts in Color Theory. In the combined Color Mixing applet, undergraduate and high school students can discover how lights, paints, and filters interact. Users can learn about the properties of incoming light, frequency, and reflectance. The site also provides activities for metamers, Triple Cell Response, and much more. Anyone seeking help with color concepts will benefit from this educational, interactive Web site.

277

Mimics and magnets: the importance of color and ecological facilitation in floral deception.  

PubMed

Plants that lack floral rewards can attract pollinators if they share attractive floral signals with rewarding plants. These deceptive plants should benefit from flowering in close proximity to such rewarding plants, because pollinators are locally conditioned on floral signals of the rewarding plants (mimic effect) and because pollinators are more abundant close to rewarding plants (magnet effect). We tested these ideas using the non-rewarding South African plant Eulophia zeyheriana (Orchidaceae) as a study system. Field observations revealed that E. zeyheriana is pollinated solely by solitary bees belonging to a single species of Lipotriches (Halictidae) that appears to be closely associated with the flowers of Wahlenbergia cuspidata (Campanulaceae), a rewarding plant with which the orchid is often sympatric. The pale blue color of the flowers of E. zeyheriana differs strongly from flowers of its congeners, but is very similar to that of flowers of W. cuspidata. Analysis of spectral reflectance patterns using a bee vision model showed that bees are unlikely to be able to distinguish the two species in terms of flower color. A UV-absorbing sunscreen was applied to the flowers of the orchid in order to alter their color, and this resulted in a significant decline in pollinator visits, thus indicating the importance of flower color for attraction of Lipotriches bees. Pollination success in the orchid was strongly affected by proximity to patches of W. cuspidata. This was evident from one of two surveys of natural populations of the orchid, as well as experiments in which we translocated inflorescences of the orchid either into patches of W. cuspidata or 40 m outside such patches. Flower color and location of E. zeyheriana plants relative to rewarding magnet patches are therefore key components of the exploitation by this orchid of the relationship between W. cuspidata and Lipotriches bee pollinators. PMID:18589523

Peter, Craig I; Johnson, Steven D

2008-06-01

278

Understanding the Effects of Floral Density on Flower Visitation Rates and Species Composition of Flower Visitors  

E-print Network

Composition of Flower Visitors by Carla Jean Essenberg Doctor of PhilosophyComposition of Flower Visitors A Dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy

Essenberg, Carla Jean

2012-01-01

279

Colorful Electrophoresis  

NSDL National Science Digital Library

In this activity, learners follow step-by-step instructions to build a gel electrophoresis chamber using inexpensive materials from local hardware and electronic stores. Then, learners follow instructions to simulate DNA electrophoresis using food colors from the kitchen pantry.

2012-06-26

280

[Evolution and development of the flower].  

PubMed

The appearance of the angiosperm flower has been an important morphological innovation in plant evolution and is thought to be, at least in part, responsible for the evolutionary success of flowering plants. Through studying and comparing the molecular basis of flower development in different model species, we can gain insights into the diversification of developmental networks that underlie the vast array of angiosperm floral morphologies. Floral development is controlled by several genes among which MADS-box genes play a crucial role as homeotic genes. Indeed, the evolution of the MADS-box transcription factor family appears to have played a pivotal role in the development of flower diversity. PMID:22463995

Vialette-Guiraud, Aurélie; Vandenbussche, Michiel

2012-01-01

281

Finding Colors  

NSDL National Science Digital Library

In this chemistry challenge, learners combine acids and bases in a universal indicator to create five different colors. Using vinegar, washing soda, and Bogen universal indicator, the goal is to find combinations that create red, orange, yellow, green, and blue solutions. Background information explains a little about how acids and bases interact to affect the pH of a solution, and how the indicator changes color based on the pH. Safety notes are included.

Sciencenter

2014-08-27

282

Fluorescence detection of tyrosinase activity on dopamine-betaxanthin purified from Portulaca oleracea (common purslane) flowers.  

PubMed

Tyrosinase or polyphenol oxidase (EC 1.14.18.1) is one of the key enzymes for the biosynthesis of natural pigment betalains. These are an important class of water-soluble pigments, characteristic of plants belonging to the order Caryophyllales. In this work, dopamine-betaxanthin (also known as miraxanthin V) is reported as the pigment responsible for the bright coloration in yellow flowers of Portulaca oleracea (common purslane). The natural pigment is purified, and used as a substrate for the catecholase (diphenolase) activity of the enzyme tyrosinase. A new, continuous method to follow the activity is developed based on the fluorescent properties of the betaxanthin. Fluorescence of the enzyme activity derived products is reported for the first time. Relevance of the fluorescent phenomenon is discussed based on fluorescence images and the description of a physiological inner filter effect present in flowers of P. oleracea. The first description of the betalain content in flower pistils is also provided. PMID:19227976

Gandía-Herrero, Fernando; Jiménez-Atiénzar, Mercedes; Cabanes, Juana; Escribano, Josefa; García-Carmona, Francisco

2009-03-25

283

Making Smart Food Choices  

MedlinePLUS

... Get Free Stuff Be a Partner Making Smart Food Choices Regular physical activity and a healthy diet ... hand in hand. Go4Life points you to wise food choices important for good health: eat a variety ...

284

Your Genes, Your Choices  

MedlinePLUS

Your Genes, Your Choices describes the Human Genome Project, the science behind it, and the ethical, legal, and social ... Nothing could be further from the truth. Your Genes, Your Choices points out how the progress of ...

285

Processing Color in Astronomical Imagery  

E-print Network

Every year, hundreds of images from telescopes on the ground and in space are released to the public, making their way into popular culture through everything from computer screens to postage stamps. These images span the entire electromagnetic spectrum from radio waves to infrared light to X-rays and gamma rays, a majority of which is undetectable to the human eye without technology. Once these data are collected, one or more specialists must process the data to create an image. Therefore, the creation of astronomical imagery involves a series of choices. How do these choices affect the comprehension of the science behind the images? What is the best way to represent data to a non-expert? Should these choices be based on aesthetics, scientific veracity, or is it possible to satisfy both? This paper reviews just one choice out of the many made by astronomical image processors: color. The choice of color is one of the most fundamental when creating an image taken with modern telescopes. We briefly explore the ...

Arcand, Kimberly K; Rector, Travis; Levay, Zoltan G; DePasquale, Joseph; Smarr, Olivia

2013-01-01

286

A Chromoplast-Specific Carotenoid Biosynthesis Pathway Is Revealed by Cloning of the Tomato white-flower Locus[W  

PubMed Central

Carotenoids and their oxygenated derivatives xanthophylls play essential roles in the pigmentation of flowers and fruits. Wild-type tomato (Solanum lycopersicum) flowers are intensely yellow due to accumulation of the xanthophylls neoxanthin and violaxanthin. To study the regulation of xanthophyll biosynthesis, we analyzed the mutant white-flower (wf). It was found that the recessive wf phenotype is caused by mutations in a flower-specific ?-ring carotene hyroxylase gene (CrtR-b2). Two deletions and one exon-skipping mutation in different CrtR-b2 wf alleles abolish carotenoid biosynthesis in flowers but not leaves, where the homologous CrtR-b1 is constitutively expressed. A second ?-carotene hydroxylase enzyme as well as flower- and fruit-specific geranylgeranyl diphosphate synthase, phytoene synthase, and lycopene ?-cyclase together define a carotenoid biosynthesis pathway active in chromoplasts only, underscoring the crucial role of gene duplication in specialized plant metabolic pathways. We hypothesize that this pathway in tomato was initially selected during evolution to enhance flower coloration and only later recruited to enhance fruit pigmentation. The elimination of ?-carotene hydroxylation in wf petals results in an 80% reduction in total carotenoid concentration, possibly caused by the inability of petals to store high concentrations of carotenoids other than xanthophylls and by degradation of ?-carotene, which accumulates as a result of the wf mutation but is not due to altered expression of genes in the biosynthetic pathway. PMID:16816137

Galpaz, Navot; Ronen, Gil; Khalfa, Zehava; Zamir, Dani; Hirschberg, Joseph

2006-01-01

287

Harmonious colors: from alchemy to science  

NASA Astrophysics Data System (ADS)

There is a very long tradition in designing color palettes for various applications, going back to at least the Upanishad. Although color palettes have been influenced by the available colorants, starting with the advent of aniline dyes in the late 1850s there have been few physical limits on the choice of individual colors. This abundance of choices exacerbates the problem of limiting the number of colors in a palette, i.e., in keeping them into a manageable quantity. For example, it is not practical for a car company to offer each model in hundreds of colors. Instead, for each model year a small number of color palettes is offered, each containing the colors for the body, trim, interior, etc. Another example is the fashion industry, where in addition to solid colors there are also patterns, leading to a huge variety of combinations that would be impossible to stock. The traditional solution is that of "color forecasting." Color consultants assess the sentiment or affective state of a target customer class and compare it with new colorants offered by the industry. They assemble a limited color palette, name the colors according to the sentiment, and publish their result. Textile manufacturers will produce fabrics in these colors and fashion designers will design clothes, accessories, and furniture based on these fabrics. Eventually, the media will communicate these forecasts to the consumers, who will be admired by their cohorts when they choose colors from the forecast palette, which by then is widely diffused. The color forecasting business is very labor intensive and difficult, thus for years computer engineers have tried to come up with algorithms to design harmonious color palettes, alas with little commercial success. For example, Johannes Itten's color theory has been implemented many times, but despite Itten's success in the Bauhaus artifacts, the computer tools have been of little utility. Indeed, contrary to the auditory sense, there is no known physiological mechanism sustaining harmony and the term "harmonious" just has the informal meaning of "going well together." We argue that the intellectual flaw resides in the belief that a masterful individual can devise a "perfect methodology" that the engineer can then reduce to practice in a computer program. We suggest that the correct approach is to consider color forecasting as an act of distillation, where a palette is digested from the sentiment of a very large number of people. We describe how this approach can be reduced to an algorithm by replacing the subjective process with a data analytic process.

Beretta, Giordano B.; Moroney, Nathan M.

2012-01-01

288

Comparative Genomic Analysis of Soybean Flowering Genes  

PubMed Central

Flowering is an important agronomic trait that determines crop yield. Soybean is a major oilseed legume crop used for human and animal feed. Legumes have unique vegetative and floral complexities. Our understanding of the molecular basis of flower initiation and development in legumes is limited. Here, we address this by using a computational approach to examine flowering regulatory genes in the soybean genome in comparison to the most studied model plant, Arabidopsis. For this comparison, a genome-wide analysis of orthologue groups was performed, followed by an in silico gene expression analysis of the identified soybean flowering genes. Phylogenetic analyses of the gene families highlighted the evolutionary relationships among these candidates. Our study identified key flowering genes in soybean and indicates that the vernalisation and the ambient-temperature pathways seem to be the most variant in soybean. A comparison of the orthologue groups containing flowering genes indicated that, on average, each Arabidopsis flowering gene has 2-3 orthologous copies in soybean. Our analysis highlighted that the CDF3, VRN1, SVP, AP3 and PIF3 genes are paralogue-rich genes in soybean. Furthermore, the genome mapping of the soybean flowering genes showed that these genes are scattered randomly across the genome. A paralogue comparison indicated that the soybean genes comprising the largest orthologue group are clustered in a 1.4 Mb region on chromosome 16 of soybean. Furthermore, a comparison with the undomesticated soybean (Glycine soja) revealed that there are hundreds of SNPs that are associated with putative soybean flowering genes and that there are structural variants that may affect the genes of the light-signalling and ambient-temperature pathways in soybean. Our study provides a framework for the soybean flowering pathway and insights into the relationship and evolution of flowering genes between a short-day soybean and the long-day plant, Arabidopsis. PMID:22679494

Jung, Chol-Hee; Wong, Chui E.; Singh, Mohan B.; Bhalla, Prem L.

2012-01-01

289

Comparative genomic analysis of soybean flowering genes.  

PubMed

Flowering is an important agronomic trait that determines crop yield. Soybean is a major oilseed legume crop used for human and animal feed. Legumes have unique vegetative and floral complexities. Our understanding of the molecular basis of flower initiation and development in legumes is limited. Here, we address this by using a computational approach to examine flowering regulatory genes in the soybean genome in comparison to the most studied model plant, Arabidopsis. For this comparison, a genome-wide analysis of orthologue groups was performed, followed by an in silico gene expression analysis of the identified soybean flowering genes. Phylogenetic analyses of the gene families highlighted the evolutionary relationships among these candidates. Our study identified key flowering genes in soybean and indicates that the vernalisation and the ambient-temperature pathways seem to be the most variant in soybean. A comparison of the orthologue groups containing flowering genes indicated that, on average, each Arabidopsis flowering gene has 2-3 orthologous copies in soybean. Our analysis highlighted that the CDF3, VRN1, SVP, AP3 and PIF3 genes are paralogue-rich genes in soybean. Furthermore, the genome mapping of the soybean flowering genes showed that these genes are scattered randomly across the genome. A paralogue comparison indicated that the soybean genes comprising the largest orthologue group are clustered in a 1.4 Mb region on chromosome 16 of soybean. Furthermore, a comparison with the undomesticated soybean (Glycine soja) revealed that there are hundreds of SNPs that are associated with putative soybean flowering genes and that there are structural variants that may affect the genes of the light-signalling and ambient-temperature pathways in soybean. Our study provides a framework for the soybean flowering pathway and insights into the relationship and evolution of flowering genes between a short-day soybean and the long-day plant, Arabidopsis. PMID:22679494

Jung, Chol-Hee; Wong, Chui E; Singh, Mohan B; Bhalla, Prem L

2012-01-01

290

Privatization and Educational Choice.  

ERIC Educational Resources Information Center

This book describes how and why educational choice movements will affect public education. It uses a public-choice approach to argue that both the supporters and opponents of private and school choice have failed to address several critical issues. Following an introductory chapter, chapter 2 is devoted to the rationale for contracting out…

Lieberman, Myron

291

biotechnologies: technology, choice  

E-print Network

Emerging biotechnologies: technology, choice and the public good #12;Nuf eld Council on Bioethics on Bioethics or visit the website. http://www.espcolour.co.uk #12;Emerging biotechnologies: technology, choice-opted member of the Council while chairing the Working Party on Emerging biotechnologies: technology, choice

Sussex, University of

292

Cross-Cultural Color-Odor Associations  

PubMed Central

Colors and odors are associated; for instance, people typically match the smell of strawberries to the color pink or red. These associations are forms of crossmodal correspondences. Recently, there has been discussion about the extent to which these correspondences arise for structural reasons (i.e., an inherent mapping between color and odor), statistical reasons (i.e., covariance in experience), and/or semantically-mediated reasons (i.e., stemming from language). The present study probed this question by testing color-odor correspondences in 6 different cultural groups (Dutch, Netherlands-residing-Chinese, German, Malay, Malaysian-Chinese, and US residents), using the same set of 14 odors and asking participants to make congruent and incongruent color choices for each odor. We found consistent patterns in color choices for each odor within each culture, showing that participants were making non-random color-odor matches. We used representational dissimilarity analysis to probe for variations in the patterns of color-odor associations across cultures; we found that US and German participants had the most similar patterns of associations, followed by German and Malay participants. The largest group differences were between Malay and Netherlands-resident Chinese participants and between Dutch and Malaysian-Chinese participants. We conclude that culture plays a role in color-odor crossmodal associations, which likely arise, at least in part, through experience. PMID:25007343

Levitan, Carmel A.; Ren, Jiana; Woods, Andy T.; Boesveldt, Sanne; Chan, Jason S.; McKenzie, Kirsten J.; Dodson, Michael; Levin, Jai A.; Leong, Christine X. R.; van den Bosch, Jasper J. F.

2014-01-01

293

Egg Yolk Color as Affected by Saponification of Different Natural Pigmenting Sources  

Microsoft Academic Search

SUMMARY Two experiments were conducted to study the influence of saponification of various yellow, red, or yellow and red xanthophylls from marigold flower and paprika fruit included at graded levels on egg yolk coloration in table and breaking eggs. Pigmentation was measured visually by the Roche yolk color fan, a subjective method, and by reflectance colorimetry, using a HunterLab MiniScan

J. Galobart; R. Sal; X. Rincon-Carruyo; E. G. Manzanilla; B. Vil; J. Gas

294

Ornamental plumage coloration and condition are dependent on age in eastern bluebirds Sialia sialis  

Microsoft Academic Search

Male eastern bluebirds Sialia sialis have striking ultraviolet (UV)-blue coloration on their heads, backs, rumps, wings, and tails and bold chestnut coloration on their breasts. These colored areas are ornaments that correlate with pairing date and reproductive effort, and thus probably influence the choice of mates by females. Such ornaments are expected to increase in color with age and body

Lynn Siefferman; Geoffrey E. Hill; F. Stephen Dobson

2005-01-01

295

Bee covered in pollen inside a flower  

NSDL National Science Digital Library

Unlike animals, plants are unable to move and find other plants to mate with. Thus, plants rely on insects and other animals to transfer pollen (male sperm) from one flower to the female sex organ (carpels) on another flower. This is called pollination.

Katie Hale (CSUF; Biological Sciences)

2007-06-19

296

'DREAM CATCHER' AND 'FIRST LADY' FLOWERING CHERRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ornamental flowering cherry trees (Prunus L. species) are popular landscape plants, made famous in the U.S. by the historic Tidal Basin cherries planted in Washington, D.C. Although planted primarily for their spring bloom, flowering cherries are also used as street or shade trees, and are valued fo...

297

Nutritional dynamics of olive tree flowers  

Microsoft Academic Search

The nutrient element fluctuations of olive tree flowers (Olea europaea L. cv ‘Konservolia') during their development were studied, since this period is a crucial one for the productivity of the tree. The profiles of number and kind of flowers along inflorescence were also recorded at the yellowish petal stage (one week before full bloom) in relation to the nutritional element

D. L. Bouranis; C. K. Kitsaki; S. N. Chorianopoulou; G. Aivalakis; J. B. Drossopoulos

1999-01-01

298

Analysis of soybean flowering-time genes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Control of soybean flowering time is important for geographic adaptation, and maximizing yield. RT-PCR analysis was performed using primers synthesized for a number of putative flowering-time genes based on homology of soybean EST and genomic sequences to Arabidopsis genes. RNA for cDNA synthesis ...

299

Flowers that destroy high-latitude ozone  

NSDL National Science Digital Library

Satellite estimates of worldwide bromine levels and sea ice coverage were analyzed. Results indicate a correlation between frost flowers and ozone depletion. Researchers suggest that trace gases produced by frost flowers may explain the huge amounts of aerosols seen in the polar troposphere and the thinning of the ozone layer during the polar sunrise.

Kaleschke et al.

300

Arabidopsis, the Rosetta Stone of Flowering Time?  

Microsoft Academic Search

Multiple environmental and endogenous inputs regulate when plants flower. The molecular genetic dissection of flowering time control in Arabidopsis has identified an integrated network of pathways that quantitatively control the timing of this developmental switch. This framework provides the basis to understand the evolution of different reproductive strategies and how floral pathways interact through seasonal progression.

Gordon G. Simpson; Caroline Dean

2002-01-01

301

Postharvest: Cut flowers and potted plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

In the past fifty years, the cut flower market has changed dramatically, from a local market with growers located on city outskirts, to a global one; flowers and cut foliage sourced from throughout the world are sold as bunches or combined into arrangements and bouquets in the major target markets. ...

302

Plant physiology Acclimatization and flower induction  

E-print Network

, 100%). From the successfully acclimatized plants, 200 plants were taken for artificial flowerPlant physiology Acclimatization and flower induction of tissue culture derived cocoyam (Xanthosoma sagittifolium Schott) plants OU Onokpise1 JT Tambong2 L Nyochembeng2 JG Wutoh3 Florida A & M University, 1

Paris-Sud XI, Université de

303

Colored Traveling Salesman Problem.  

PubMed

The multiple traveling salesman problem (MTSP) is an important combinatorial optimization problem. It has been widely and successfully applied to the practical cases in which multiple traveling individuals (salesmen) share the common workspace (city set). However, it cannot represent some application problems where multiple traveling individuals not only have their own exclusive tasks but also share a group of tasks with each other. This work proposes a new MTSP called colored traveling salesman problem (CTSP) for handling such cases. Two types of city groups are defined, i.e., each group of exclusive cities of a single color for a salesman to visit and a group of shared cities of multiple colors allowing all salesmen to visit. Evidences show that CTSP is NP-hard and a multidepot MTSP and multiple single traveling salesman problems are its special cases. We present a genetic algorithm (GA) with dual-chromosome coding for CTSP and analyze the corresponding solution space. Then, GA is improved by incorporating greedy, hill-climbing (HC), and simulated annealing (SA) operations to achieve better performance. By experiments, the limitation of the exact solution method is revealed and the performance of the presented GAs is compared. The results suggest that SAGA can achieve the best quality of solutions and HCGA should be the choice making good tradeoff between the solution quality and computing time. PMID:25494521

Li, Jun; Zhou, MengChu; Sun, Qirui; Dai, Xianzhong; Yu, Xiaolong

2014-12-01

304

PHYTOCHROME-DEPENDENT LATE-FLOWERING accelerates flowering through physical interactions with phytochrome B and CONSTANS.  

PubMed

In flowering plants, light is one of the major environmental stimuli that determine the timing of the transition from the vegetative to reproductive phase. In Arabidopsis, phytochrome B (phyB); phyA; cryptochrome 2; and flavin-binding, KELCH repeat, F-BOX 1 are major photoreceptors that regulate flowering. Unlike phyA; cryptochrome 2; and flavin-binding, KELCH repeat, F-BOX 1, phyB delays flowering mainly by destabilizing the CONSTANS (CO) protein, whose reduction leads to decreased expression of a florigen gene, flowering locus T. However, it remains unclear how the phyB-mediated CO destabilization is mechanistically regulated. Here, we identify a unique phytochrome-dependent late-flowering (PHL) gene, which is mainly involved in the phyB-dependent regulation of flowering. Plants with mutant phl exhibited a late-flowering phenotype, especially under long-day conditions. The late-flowering phenotype of the phl mutant was completely overridden by a phyB mutation, indicating that PHL normally accelerates flowering by countering the inhibitory effect of phyB on flowering. Accordingly, PHL physically interacted with phyB both in vitro and in vivo in a red light-dependent manner. Furthermore, in the presence of phyB under red light, PHL interacted with CO as well. Taken together, we propose that PHL regulates photoperiodic flowering by forming a phyB-PHL-CO tripartite complex. PMID:24127609

Endo, Motomu; Tanigawa, Yoshiyasu; Murakami, Tadashi; Araki, Takashi; Nagatani, Akira

2013-10-29

305

Colorful Mathematics  

NSDL National Science Digital Library

Funded by Industry Canada's SchoolNet initiative with the cooperation of the Canadian Mathematical Society, Colorful Mathematics takes a game-oriented approach to teaching K-12 mathematics. The project has developed five coloring games that teach children about problem solving, and pattern identification, which "are all at the very heart of mathematics." The coloring approach makes difficult graph concepts "that are still the subject of active research by mathematicians, computer scientists and industry researchers" more accessible to children. The software program, which is available for free from this website, is set up to check for mistakes and challenge students to improve on their results. A Teacher's Corner section gives an overview of the games, "some sample questions for discussion with the curious student," and an overview of terminology used in the software program. The website is also available in French.

306

Colorful Waves  

NSDL National Science Digital Library

You're probably really upset that all you have so far is a simple little ray model of light. When do we get to the good stuff, you say? How about now? As a bonus, you get to look at lots of pretty colors. This chapter addresses how light can be modeled as a series of waves. These waves consist of changing electric and magnetic fields that can travel through empty space, as well as through other mediums. Different frequencies of light waves correspond to different colors of light. White light is composed of all the colors of visible light. Visible light is just a small portion of the entire spectrum of electromagnetic waves.

William C. Robertson, Ph.D.

2003-01-01

307

Induction of flowering by 5-azacytidine in some plant species: relationship between the stability of photoperiodically induced flowering and flower-inducing effect of DNA demethylation.  

PubMed

The flower-inducing effect of 5-azacytidine, a DNA demethylating reagent, was examined in several plant species with a stable or unstable photoperiodically induced flowering state under non-inductive photoperiodic conditions. The long day plant Silene armeria, whose flowering state is stable and the short day plant Pharbitis nil, whose flowering state is unstable were induced to flower by 5-azacytidine under a non-inductive condition. Thus, the replacement of photoinduction by 5-azacytidine treatment is not specific to Perilla frutescens. On the other hand, 5-azacytidine did not induce flowering in Xanthium strumarium whose flowering state is stable and Lemna paucicostata whose flowering state is unstable. Thus, epigenetics caused by DNA demethylation may be involved in the regulation of photoperiodic flowering irrespective of the stability of the photoperiodically induced flowering state. PMID:18251884

Kondo, Hiroshi; Miura, Takashi; Wada, Kaede C; Takeno, Kiyotoshi

2007-11-01

308

Kool Colors  

NSDL National Science Digital Library

Learners investigate how temperature affects the rate of chemical reactions by observing how steel wool reacts with various types of Kool-Aid solutions at different temperatures. The reaction is monitored as the color fades in the Kool-Aid solutions. Background information includes how the dyes change color from an oxidation-reduction reaction. Extensions include investigating how surface area and concentration affect reaction rate. Part of the "No Hassle Messy Science with a Wow" activity guide by OMSI, where all activities use only household materials.

Oregon Museum of Science and Industry

2007-01-01

309

Context-dependent reproductive isolation mediated by floral scent and color.  

PubMed

Reproductive isolation due to pollinator behavior is considered a key mode of speciation in flowering plants. Although floral scent is thought to mediate pollinator behavior, little is known about its effects on pollinator attraction and floral visitation in the wild. We used field experiments with wild hawkmoths and laboratory experiments with naďve hawkmoths to investigate attraction to and probing of flowers in response to indole, a volatile emitted by Ipomopsis tenuituba but not its close relative I. aggregata, both alone and in combination with floral color differences. We demonstrated that indole attracts wild hawkmoths to flowers, but has little effect on the rate at which those attracted moths probe flowers. In contrast, white flower color did not influence hawkmoth attraction in the field, but caused more attracted moths to probe flowers. Thus, the moths require both scent and high visual contrast, in that order, to feed at flowers at dusk. Their preference for indole-scented flowers is innate, but species-specific preference is mitigated by previous experience and plant spatial patterning. This context-dependent behavior helps explain why these Ipomopsis species show geographical variation in the extent of hybridization and may potentially explain formation of hybrid bridges in other systems of hawkmoth-pollinated plants. PMID:25354994

Bischoff, Mascha; Raguso, Robert A; Jürgens, Andreas; Campbell, Diane R

2015-01-01

310

Effects of stimulus duration and choice delay on visual categorization in pigeons  

PubMed Central

We (Lazareva, Freiburger, & Wasserman, 2004) previously trained four pigeons to classify color photographs into their basic-level categories (cars, chairs, flowers, or people) or into their superordinate-level categories (natural or artificial). Here, we found that brief stimulus durations had the most detrimental effect on the basic-level discrimination of natural stimuli by the same pigeons. Increasing the delay between stimulus presentation and choice responding had greater detrimental effect on the basic-level discrimination than the superordinate-level discrimination. These results suggest that basic-level discriminations required longer stimulus durations and were more subject to forgetting than were superordinate-level discriminations. Additionally, categorization of natural stimuli required longer stimulus durations than categorization of artificial stimuli, but only at the basic level. Together, these findings suggest that basic-level categorization may not always be superior to superordinate-level categorization and provide additional evidence of a dissociation between natural and artificial stimuli in pigeons’ categorization. PMID:20161256

Lazareva, Olga F.; Wasserman, Edward A.

2009-01-01

311

Flowers help bees cope with uncertainty: signal detection and the function of floral complexity  

PubMed Central

Plants often attract pollinators with floral displays composed of visual, olfactory, tactile and gustatory stimuli. Since pollinators' responses to each of these stimuli are usually studied independently, the question of why plants produce multi-component floral displays remains relatively unexplored. Here we used signal detection theory to test the hypothesis that complex displays reduce a pollinator's uncertainty about the floral signal. Specifically, we asked whether one component of the floral display, scent, improved a bee's certainty about the value of another component, color hue. We first trained two groups of bumble bees (Bombus impatiens Cresson) to discriminate between rewarding and unrewarding artificial flowers of slightly different hues in the presence vs absence of scent. In a test phase, we presented these bees with a gradient of floral hues and assessed their ability to identify the hue rewarded during training. We interpreted the extent to which bees' preferences were biased away from the unrewarding hue (‘peak shift’) as an indicator of uncertainty in color discrimination. Our data show that the presence of an olfactory signal reduces uncertainty regarding color: not only was color learning facilitated on scented flowers but also bees showed a lower amount of peak shift in the presence of scent. We explore potential mechanisms by which scent might reduce uncertainty about color, and discuss the broader significance of our results for our understanding of signal evolution. PMID:21147975

Leonard, Anne S.; Dornhaus, Anna; Papaj, Daniel R.

2011-01-01

312

Examining Colors, Color Perception, and Sight  

NSDL National Science Digital Library

Students of all ages are fascinated by color and how we perceive it. For the main activity in this chapter, your class explores colors and visual perception by mixing colors in several ways. Students learn more about colors, light, vision, and color compo

John Eichinger

2009-05-15

313

The Families of Flowering Plants  

NSDL National Science Digital Library

Australian authors L. Watson and M. J. Dallwitz have updated this magnificent resource of detailed character descriptions, taxonomic information, references, and line illustrations of "all the Angiosperm families" from Acanthaceae to Zygophyllaceae. Users will find extensive data on plant and flower morphology, "seedling germination type, embryology, anther ontogeny, pollen cytology and morphology, stigma type, sieve-tube plastids, leaf, stem, nodal and wood anatomy, and phytochemistry (phenolics, alkaloids, cyanogenesis, etc.)." Watson and Dallwitz also include detailed taxonomic information on family synonyms, "numbers of species and genera in each family, and complete lists or (in the case of the largest families only) examples of the genera in each." A character list and an 'implicit attributes' section accompany the resource; information for downloading is available at the site. For teachers and graduate students alike, this online resource will be hard to beat.

314

Colorful Accounting  

ERIC Educational Resources Information Center

As instructors of accounting, we should take an abstract topic (at least to most students) and connect it to content known by students to help increase the effectiveness of our instruction. In a recent semester, ordinary items such as colors, a basketball, and baseball were used to relate the subject of accounting. The accounting topics of account…

Warrick, C. Shane

2006-01-01

315

[Carpel development in male flowers of cucumber (Cucumis sativus. L)].  

PubMed

Carpel development in cucumber male flowers was studied by morphological, histochemical and isoenzyme electrophoretic analyses. The results showed that: (1) cell number of the carpel in male flowers increased continuously during the development of male flowers, and the carpel in male flowers was abundant in RNA content; (2) the carpel in male flowers at latter developmental stage was differentiated, and a placenta-like structure was formed in the carpel of male flowers during anthesis, while the ovule did not appear as that of mature female flowers; (3) The POD and esterase isoenzyme electrophoretic profiles of carpel varied from the development of male flowers, which further indicated that the carpel in mature male flowers was no longer at the stage of primordium. It could be deduced from the results that carpel of cucumber male flowers develops continuously in a distinct pattern with that of female flowers during sex expression process. PMID:15133901

Yuan, Gao Feng; Wang, Qiao Mei

2004-02-01

316

Spectral Sensitivities and Color Signals in a Polymorphic Damselfly  

PubMed Central

Animal communication relies on conspicuous signals and compatible signal perception abilities. Good signal perception abilities are particularly important for polymorphic animals where mate choice can be a challenge. Behavioral studies suggest that polymorphic damselflies use their varying body colorations and/or color patterns as communication signal for mate choice and to control mating frequencies. However, solid evidence for this hypothesis combining physiological with spectral and behavioral data is scarce. We investigated this question in the Australian common blue tail damselfly, Ischnura heterosticta, which has pronounced female-limited polymorphism: andromorphs have a male-like blue coloration and gynomorphs display green/grey colors. We measured body color reflectance and investigated the visual capacities of each morph, showing that I. heterosticta have at least three types of photoreceptors sensitive to UV, blue, and green wavelength, and that this visual perception ability enables them to detect the spectral properties of the color signals emitted from the various color morphs in both males and females. We further demonstrate that different color morphs can be discriminated against each other and the vegetation based on color contrast. Finally, these findings were supported by field observations of natural mating pairs showing that mating partners are indeed chosen based on their body coloration. Our study provides the first comprehensive evidence for the function of body coloration on mate choice in polymorphic damselflies. PMID:24498233

Huang, Shao-chang; Chiou, Tsyr-huei; Marshall, Justin; Reinhard, Judith

2014-01-01

317

Flower opening and closure: an update.  

PubMed

This review is an update of a 2003 review (Journal of Experimental Botany 54,1801-1812) by the same corresponding author. Many examples of flower opening have been recorded using time-lapse photography, showing its velocity and the required elongation growth. Ethylene regulates flower opening, together with at least gibberellins and auxin. Ethylene and gibberellic acid often promote and inhibit, respectively, the expression of DELLA genes and the stability of DELLA proteins. DELLA results in growth inhibition. Both hormones also inhibited and promoted, respectively, the expression of aquaporin genes required for cell elongation. Arabidopsis miRNA319a mutants exhibited narrow and short petals, whereby miRNA319a indirectly regulates auxin effects. Flower opening in roses was controlled by a NAC transcription factor, acting through miRNA164. The regulatory role of light and temperature, in interaction with the circadian clock, has been further elucidated. The end of the life span in many flowers is determined by floral closure. In some species pollination resulted in earlier closure of turgid flowers, compared with unpollinated flowers. It is hypothesized that this pollination-induced effect is only found in flowers in which closure is regulated by ethylene. PMID:25135521

van Doorn, Wouter G; Kamdee, Chanattika

2014-11-01

318

On the purposes of color for living beings: toward a theory of color organization.  

PubMed

Phylogenetic and paleontological evidence indicates that in the animal kingdom the ability to perceive colors evolved independently several times over the course of millennia. This implies a high evolutionary neural investment and suggests that color vision provides some fundamental biological benefits. What are these benefits? Why are some animals so colorful? What are the adaptive and perceptual meanings of polychromatism? We suggest that in addition to the discrimination of light and surface chromaticity, sensitivity to color contributes to the whole, the parts and the fragments of perceptual organization. New versions of neon color spreading and the watercolor illusion indicate that the visual purpose of color in humans is threefold: to inter-relate each chromatic component of an object, thus favoring the emergence of the whole; to support a part-whole organization in which components reciprocally enhance each other by amodal completion; and, paradoxically, to reveal fragments and hide the whole-that is, there is a chromatic parceling-out process of separation, division, and fragmentation of the whole. The evolution of these contributions of color to organization needs to be established, but traces of it can be found in Harlequin camouflage by animals and in the coloration of flowers. PMID:24374380

Pinna, Baingio; Reeves, Adam

2015-01-01

319

Anthocyanins as Functional Food Colors  

NASA Astrophysics Data System (ADS)

Anthocyanins, a proanthocyanidin-type of flavonoid, contain an abundance of functional phytochemicals and occur in fruits such as cranberry, blueberry, orange, apple and in vegetables such as tomato, sweet pepper, spinach, and radishes. Functional and essential diets have been ingested in daily life since the primitive era of history. When anthocyanins are coupled with some water-soluble sugar molecules, their color becomes red, yellow, violet, or blue. It is very intriguing that anthocyanins provide the colorful variety of pigments for pansies, petunias, plums, and other diverse flowers. Chlorophyll in various fruits and vegetables is the main green phyto-component, while anthocyanins are probably the most important visible plant pigments in the natural kingdom having specific colors. Anthocyanins have been clinically used in many folklore medicines worldwide. Anthocyanins could provide health benefits for age-related diseases as well as other diseases. Anthocyanins have higher antioxidant capacity against oxidative stress induced by excess reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide, and thus the human body might be protected from oxidative injury by anthocyanins. On the basis of these facts, we review the synthesis of plant flavonoids and their ability to scavenge oxidants, inhibit or activate enzymes, and the safety of proanthocyanidins and anthocyanidins present in common foods.

Motohashi, Noboru; Sakagami, Hiroshi

320

Color It!  

NSDL National Science Digital Library

It doesn't take a Photoshop expert to create attractive graphics for the Web. To prove this, the folks at MicroFrontier have released three graphic creation/editing packages for the Macintosh, each aimed at a different user level. All three applications support Photoshop 3.0 compatible plug-ins and basic features such as scanner support, image and resolution scaling, and basic image enhancement. Color It! adds the ability to create animated GIFs, PNG, and progressive JPEG files, and client- and server-side image maps. It also supports an enhanced set of filters, fills, and imaging tools. A save-disabled demo version of each application is available at the MicroFrontier Website. The price for Color It! is $49.95.

321

FLATTENING FUNCTIONS ON FLOWERS EDMUND HARRISS AND OLIVER JENKINSON  

E-print Network

FLATTENING FUNCTIONS ON FLOWERS EDMUND HARRISS AND OLIVER JENKINSON Abstract. Let T. The closure of the image of a pre-image selector is called a flower, and a flower with p connected components is called a p-flower. We say that a real-valued Lipschitz function can be Lipschitz

Wright, Francis

322

Original article Rose flower production and quality as affected  

E-print Network

Original article Rose flower production and quality as affected by Ca concentration in the petal) Abstract ­ The quality of cut rose flowers at the post-harvest stage is affected by the susceptibility to Botrytis flower blight. This parameter may be related to Ca concentration in the flowers. The objective

Paris-Sud XI, Université de

323

1999 Macmillan Magazines Ltd The flowers of Ophrys orchids mimic  

E-print Network

© 1999 Macmillan Magazines Ltd The flowers of Ophrys orchids mimic receptive females of usually only one pollinator species. Males of this species are attracted primarily by the odour of a flower and transfer the pollinia during so-called `pseudocopulations' with the flowers1­3 . We have found that flowers

Paulus, Hannes F.

324

Life Cycle and Flowering Time Control Pierre Albert Pin  

E-print Network

Life Cycle and Flowering Time Control in Beet Pierre Albert Pin Faculty of Forest Science Umeĺ of developing flowers of a transgenic 35S::BvFT2 sugar beet plant. Biennial sugar beet plant (Beta vulgaris) overexpressing the Beta FLOWERING LOCUS T gene, BvFT2, succeeds to bolt and flower without vernalization

325

Effects of volatiles from Maruca vitrata larvae and caterpillar-infested flowers of their host plant Vigna unguiculata on the foraging behavior of the parasitoid Apanteles taragamae.  

PubMed

The parasitoid wasp Apanteles taragamae is a promising candidate for the biological control of the legume pod borer Maruca vitrata, which recently has been introduced into Benin. The effects of volatiles from cowpea and peabush flowers and Maruca vitrata larvae on host selection behavior of the parasitoid Apanteles taragamae were investigated under laboratory conditions by using a Y-tube olfactometer. Naďve and oviposition-experienced female wasps were given a choice between several odor sources that included (1) uninfested, (2) Maruca vitrata-infested, and (3) mechanically damaged cowpea flowers, as well as (4) stem portions of peabush plants carrying leaves and flowers, (5) healthy M. vitrata larvae, and moribund (6), and live (7) virus-infected M. vitrata larvae. Responses of naďve and oviposition-experienced female wasps did not differ for any of the odor source combinations. Wasps were significantly attracted to floral volatiles produced by cowpea flowers that had been infested with M. vitrata larvae and from which the larvae had been removed. Apanteles taragamae females also were attracted to Maruca vitrata-infested flowers after removal of both the larvae and their feces. Female wasps discriminated between volatiles from previously infested flowers and mechanically damaged flowers. Uninfested cowpea flowers attracted only oviposition-experienced wasps that had received a rewarding experience (i.e. the parasitization of two M. vitrata larvae feeding on cowpea flowers) before the olfactometer test. Wasps also were attracted to uninfested leaves and flowers of peabush. Moreover, they were also attracted to healthy and live virus-infected M. vitrata larvae, but not when the latter were moribund. Our data show that, similarly to what has been extensively been reported for foliar volatiles, flowers of plants also emit parasitoid-attracting volatiles in response to being infested with an herbivore. PMID:20842412

Dannon, Elie A; Tamň, Manuele; Van Huis, Arnold; Dicke, Marcel

2010-10-01

326

Effects of Volatiles from Maruca vitrata Larvae and Caterpillar-Infested Flowers of Their Host Plant Vigna unguiculata on the Foraging Behavior of the Parasitoid Apanteles taragamae  

PubMed Central

The parasitoid wasp Apanteles taragamae is a promising candidate for the biological control of the legume pod borer Maruca vitrata, which recently has been introduced into Benin. The effects of volatiles from cowpea and peabush flowers and Maruca vitrata larvae on host selection behavior of the parasitoid Apanteles taragamae were investigated under laboratory conditions by using a Y-tube olfactometer. Naďve and oviposition-experienced female wasps were given a choice between several odor sources that included (1) uninfested, (2) Maruca vitrata-infested, and (3) mechanically damaged cowpea flowers, as well as (4) stem portions of peabush plants carrying leaves and flowers, (5) healthy M. vitrata larvae, and moribund (6), and live (7) virus-infected M. vitrata larvae. Responses of naďve and oviposition-experienced female wasps did not differ for any of the odor source combinations. Wasps were significantly attracted to floral volatiles produced by cowpea flowers that had been infested with M. vitrata larvae and from which the larvae had been removed. Apanteles taragamae females also were attracted to Maruca vitrata-infested flowers after removal of both the larvae and their feces. Female wasps discriminated between volatiles from previously infested flowers and mechanically damaged flowers. Uninfested cowpea flowers attracted only oviposition-experienced wasps that had received a rewarding experience (i.e. the parasitization of two M. vitrata larvae feeding on cowpea flowers) before the olfactometer test. Wasps also were attracted to uninfested leaves and flowers of peabush. Moreover, they were also attracted to healthy and live virus-infected M. vitrata larvae, but not when the latter were moribund. Our data show that, similarly to what has been extensively been reported for foliar volatiles, flowers of plants also emit parasitoid-attracting volatiles in response to being infested with an herbivore. PMID:20842412

Dannon, Elie A.; Tamň, Manuele; Van Huis, Arnold

2010-01-01

327

More Choice, Less Crime  

ERIC Educational Resources Information Center

Previous research debates whether public school choice improves students' academic outcomes, but there is little examination of its effects on their nonacademic outcomes. We use data from a nationally representative sample of high school students, a previously developed Tiebout choice measure, and metropolitan-level data on teenage arrest rates to…

Dills, Angela K.; Hernandez-Julian, Rey

2011-01-01

328

Making School Choice Work  

ERIC Educational Resources Information Center

School choice is increasingly the new normal in urban education. But in cities with multiple public school options, how can civic leaders create a choice system that works for all families, whether they choose a charter or district public school? To answer this question, the Center on Reinventing Public Education (CRPE) researchers surveyed 4,000…

DeArmond, Michael; Jochim, Ashley; Lake, Robin

2014-01-01

329

The Choice Controversy.  

ERIC Educational Resources Information Center

Issues in school choice--constitutionality, feasibility, equity, and educational productivity--are examined in this book. The controversy requires an ongoing analysis of the origins of the school-choice movement, the kinds of plans proposed and implemented, their educational and social consequences, and the philosophical assumptions underlying the…

Cookson, Peter W., Jr., Ed.

330

School Choice Marches forward  

ERIC Educational Resources Information Center

One year ago, the "Wall Street Journal" dubbed 2011 "the year of school choice," opining that "this year is shaping up as the best for reformers in a very long time." School-choice laws took great strides in 2011, both in the number of programs that succeeded across states and also in the size and scope of the adopted programs. Yet education…

Butcher, Jonathan

2013-01-01

331

Attention in risky choice.  

PubMed

Previous research on the processes involved in risky decisions has rarely linked process data to choice directly. We used a simple measure based on the relative amount of attentional deployment to different components (gains/losses and their probabilities) of a risky gamble during the choice process, and we related this measure to the actual choice. In an experiment we recorded the decisions, decision times, and eye movements of 80 participants who made decisions on 11 choice problems. We used the number of eye fixations and fixation transitions to trace the deployment of attention during the choice process and obtained the following main results. First, different components of a gamble attracted different amounts of attention depending on participants' actual choice. This was reflected in both the number of fixations and the fixation transitions. Second, the last-fixated gamble but not the last-fixated reason predicted participants' choices. Third, a comparison of data obtained with eye tracking and data obtained with verbal protocols from a previous study showed a large degree of convergence regarding the process of risky choice. Together these findings tend to support dimensional decision strategies such as the priority heuristic. PMID:25226548

Brandstätter, Eduard; Körner, Christof

2014-10-01

332

Antimicrobial activity of flowers from Anthemis cotula.  

PubMed

The flavonoid containing total extract of Anthemis cotula flowers, tested at the concentration of 200 microg/ml, showed interesting antimicrobial activity against both Gram-negative and Gram-positive microorganisms. PMID:11077183

Quarenghi, M V; Tereschuk, M L; Baigori, M D; Abdala, L R

2000-12-01

333

Antimicrobial activity of flowers from Anthemis cotula  

Microsoft Academic Search

The flavonoid containing total extract of Anthemis cotula flowers, tested at the concentration of 200 ?g\\/ml, showed interesting antimicrobial activity against both Gram-negative and Gram-positive microorganisms.

M. V Quarenghi; M. L Tereschuk; M. D Baigori; L. R Abdala

2000-01-01

334

Supercooling in Overwintering Azalea Flower Buds 1  

PubMed Central

Differential thermal analysis and nuclear magnetic resonance spectroscopy experiments on whole flower buds and excised floral primordia of azalea (Rhododendron kosterianum, Schneid.) proved that supercooling is the mode of freezing resistance (avoidance) of azalea flower primordia. Increase in the linewidth of nuclear magnetic resonance spectra for water upon thawing supports the view that injury to the primordia occurs at the moment of freezing. Nonliving primordia freeze at the same temperatures as living primordia, indicating that morphological features of primordial tissues are a key factor in freezing avoidance of dormant azalea flower primordia. Differential thermal analyses was used to study the relationship of cooling rate to the freezing points of floral primordia in whole flower buds. At a cooling rate of 8.5 C per hour, primordia in whole buds froze at about the same subfreezing temperatures as did excised primordia cooled at 37 C per hour. At more rapid cooling rates primordia in intact buds froze at higher temperatures. PMID:16658832

George, Milon F.; Burke, Michael J.; Weiser, Conrad J.

1974-01-01

335

Sexual interference within flowers of Chamerion angustifolium  

Microsoft Academic Search

Hermaphroditism is prevalent in plants but may allow interference between male function (pollen removal and dispersal) and\\u000a female function (pollen receipt and seed production) within a flower. Temporal or spatial segregation of gender within a hermaphroditic\\u000a flower may evolve to reduce this interference and enhance male and female reproductive success. We tested this hypothesis\\u000a using Chamerion angustifolium (Onagraceae), in which

Matthew B. Routley; Brian C. Husband

2006-01-01

336

Expression of Sex in Flowering Plants  

Microsoft Academic Search

In a recent important review of the literature, Heslop-Harrison1 has listed external variables which may modify sex-expression in flowering plants. The effects of variations in mineral nutrition, in the light regime and in temperature, of mutilation, grafting and the application of chemicals and hormones on the differential production of pistillate and staminate flowers are described. To this review should be

H. G. Baker

1957-01-01

337

PLANT SCIENCES: Deciding When to Flower  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Plants must carefully time the switch from vegetative growth to floral production in order to take advantage of optimal environmental conditions. In their Perspective, Bastow and Dean discuss new work (He et al.) that reveals an elegant mechanism, involving chromatin remodeling of a genetic locus encoding a flowering repressor, which enables plants to regulate flowering time.

Ruth Bastow (John Innes Centre; Department of Cell and Developmental Biology)

2003-12-05

338

Why Is a Flower Five-Petaled?  

ERIC Educational Resources Information Center

This paper examines why many flowers are five-petaled through the use of a five-petaled model that draws insights from the location of cell clusters at a shoot apex, rather than by way of the Fibonacci sequence or the golden ratio as in the past. The conclusion drawn is that flowers are most likely to be five-petaled, followed by six-petaled;…

Nishiyama, Yutaka

2004-01-01

339

Classification and geography of the flowering plants  

Microsoft Academic Search

Thome, Robert F. (Rancho Santa Ana Botanic Garden, Claremont, CA 91711). Classification and geography of the flowering plants.\\u000a Bot. Rev.58(3): 225–348. 1992.—This treatment of the flowering plants is the latest revision of my classification of the Class Angiospermae\\u000a and replaces my 1983 and more recent 1992 synopses. An update is necessary because so much new information has been published\\u000a in

Robert F. Thorne

1992-01-01

340

Is the flower fluorescence relevant in biocommunication?  

Microsoft Academic Search

Flower fluorescence has been previously proposed as a potential visual signal to attract pollinators. In this work, this point\\u000a was addressed by quantitatively measuring the fluorescence quantum yield (?\\u000a f) for flowers of Bellis perennis (white, yellow, pink, and purple), Ornithogalum thyrsoides (petals and ovaries), Limonium sinuatum (white and yellow), Lampranthus productus (yellow), Petunia nyctaginiflora (white), Bougainvillea spectabilis (white and

Analía Iriel; María Gabriela Lagorio

2010-01-01

341

Synchrony in the phenology of a culturally iconic spring flower  

NASA Astrophysics Data System (ADS)

We examine the flowering phenology of the cultural iconic Spring Snowflake Leucojum vernum, a considerable tourist attraction, recorded from two sites in western Poland. Flowering dates at the two sites were closely correlated but about 6 days later at the more natural area. The end of flowering was associated with the start of canopy leafing. Early flowering was related to a longer flowering season which may benefit ecotourism under future climate warming.

Sparks, Tim H.; Mizera, Tadeusz; Wójtowicz, Wanda; Tryjanowski, Piotr

2012-03-01

342

Sex determination in flowering plants.  

PubMed Central

In many ways, plants offer unique systems through which to study sex determination. Because the production of unisexual flowers has evolved independently in many plant species, different and novel mechanisms may be operational. Hence, there is probably not one unifying mechanism that explains sex determination in plants. Advances in our understanding of sex determination will come from the analysis of the genetics, molecular biology, and biochemistry of genes controlling sexual determination in plants. Several excellent model systems for bisexual floral development (Arabidopsis and Antirrhinum), monoecy (maize), and dioecy (Silene, asparagus, and mercury) are available for such analyses. The important questions that remain concern the mechanism of action of sex determination genes and their interrelationship, if any, with homeotic genes that determine the sexual identity of floral organ primordia. At the physiological level, the connection between hormone signaling and sexuality is not well understood, although significant correlations have been discovered. Finally, once the genes that regulate these processes are identified, cloned, and studied, new strategies for the manipulation of sexuality in plants should be forthcoming. PMID:8281039

Dellaporta, S L; Calderon-Urrea, A

1993-01-01

343

Ring Beholds a Delicate Flower  

NASA Technical Reports Server (NTRS)

NASA's Spitzer Space Telescope finds a delicate flower in the Ring Nebula, as shown in this image. The outer shell of this planetary nebula looks surprisingly similar to the delicate petals of a camellia blossom. A planetary nebula is a shell of material ejected from a dying star. Located about 2,000 light years from Earth in the constellation Lyra, the Ring Nebula is also known as Messier Object 57 and NGC 6720. It is one of the best examples of a planetary nebula and a favorite target of amateur astronomers.

The 'ring' is a thick cylinder of glowing gas and dust around the doomed star. As the star begins to run out of fuel, its core becomes smaller and hotter, boiling off its outer layers. The telescope's infrared array camera detected this material expelled from the withering star. Previous images of the Ring Nebula taken by visible-light telescopes usually showed just the inner glowing loop of gas around the star. The outer regions are especially prominent in this new image because Spitzer sees the infrared light from hydrogen molecules. The molecules emit infrared light because they have absorbed ultraviolet radiation from the star or have been heated by the wind from the star.

Download the QuickTime movie for the animated version of this Ring Nebula image.

2005-01-01

344

Phytochrome, plant growth and flowering  

NASA Technical Reports Server (NTRS)

Attempts to use artificially lit cabinets to grow plants identical to those growing in sunlight have provided compelling evidence of the importance of light quality for plant growth. Changing the balance of red (R) to far-red (FR) radiation, but with a fixed photosynthetic input can shift the phytochrome photoequilibrium in a plant and generate large differences in plant growth. With FR enrichment the plants elongate, and may produce more leaf area and dry matter. Similar morphogenic responses are also obtained when light quality is altered only briefly (15-30 min) at the end-of-the-day. Conversely, for plants grown in natural conditions the response of plant form to selective spectral filtering has again shown that red and far-red wavebands are important as found by Kasperbauer and coworkers. Also, where photosynthetic photon flux densities (PPFD) of sunlight have been held constant, the removal of far-red alone alters plant growth. With FR depletion plants grown in sunlight are small, more branched and darker green. Here we examine the implications for plant growth and flowering when the far-red composition of incident radiation in plant growth chambers is manipulated.

King, R. W.; Bagnall, D. J.

1994-01-01

345

Lattice-preserving Flower Constellations under perturbations  

NASA Astrophysics Data System (ADS)

2D Lattice Flower Constellations (2D-LFCs) are stable in the Keplerian model. This means that a flower constellation maintains its structure (the lattice) at any instant of time. However, this is not necessarily true when the harmonic is included in the gravitational potential of the Earth. This paper deals with the new theory of Lattice-preserving Flower Constellations, which shows how 2D-LFC can be designed in such a way that the relative displacement of the orbital parameters of its satellites is invariant even under the presence of the effect. This is achieved following two different procedures: the first consists of the modification of the semi-major axis of all the satellites in a 2D-LFC slightly to control their orbital period, and the second consists of the modification of the values for the eccentricity and inclination, so that the perturbations result in motion that still preserves the lattice of the flower constellation. The proposed theory of Lattice-preserving Flower Constellations validates the theory of 3D Lattice Flower Constellations and has a wide range of potential applications.

Casanova, Daniel; Avendańo, Martín; Tresaco, Eva

2015-01-01

346

Color rendering of art paintings under CIE illuminants for normal and color deficient observers.  

PubMed

Color rendering indices are used to access the quality of lighting but, in addition to other well-known limitations, are not defined for color deficient observers. We evaluated the quality of lighting for normal and color deficient observers in the context of art paintings by estimating the number of colors they perceive when looking at the paintings. Hyperspectral data from 11 oil paintings were analyzed to compute the number of discernible colors when the paintings were assumed rendered under 55 CIE illuminants. Models of color perception for normal and color deficient observers were applied in the estimates. It was found that the number of discernible colors for normal and color deficient observers had low correlation with traditional color rendering indices and that some three-band illuminants, like HP4, were found to be good for most cases, except for tritanopes. These results suggest that it may be possible to obtain good lighting conditions for normal and color deficient observers with an appropriate choice of the light source. PMID:19568303

Maciel Linhares, Joăo Manuel; Araújo Pinto, Paulo Daniel; Cardoso Nascimento, Sérgio Miguel

2009-07-01

347

Strawberry homologue of TERMINAL FLOWER1 integrates photoperiod and temperature signals to inhibit flowering.  

PubMed

Photoperiod and temperature are major environmental signals affecting flowering in plants. Although molecular pathways mediating these signals have been well characterized in the annual model plant Arabidopsis, much less information is known in perennials. Many perennials including the woodland strawberry (Fragaria vesca L.) are induced to flower in response to decreasing photoperiod and temperature in autumn and they flower following spring. We showed earlier that, in contrast with Arabidopsis, the photoperiodic induction of flowering in strawberry occurs in short days (SD) when the decrease in FvFT1 (FLOWERING LOCUS T) and FvSOC1 (SUPPRESSOR OF THE OVEREXPRESSION OF CONSTANS1) expression leads to lower mRNA levels of the floral repressor, FvTFL1 (TERMINAL FLOWER1). By using transgenic lines and gene expression analyses, we show evidence that the temperature-mediated changes in the FvTFL1 mRNA expression set critical temperature limits for the photoperiodic flowering in strawberry. At temperatures below 13°C, low expression level of FvTFL1 in both SD and long days (LD) allows flower induction to occur independently of the photoperiod. Rising temperature gradually increases FvTFL1 mRNA levels under LD, and at temperatures above 13°C, SD is required for the flower induction that depends on the deactivation of FvSOC1 and FvTFL1. However, an unknown transcriptional activator, which functions independently of FvSOC1, enhances the expression of FvTFL1 at 23°C preventing photoperiodic flowering. We suggest that the observed effect of the photoperiod × temperature interaction on FvTFL1 mRNA expression may allow strawberry to induce flowers in correct time in different climates. PMID:25720985

Rantanen, Marja; Kurokura, Takeshi; Jiang, Panpan; Mouhu, Katriina; Hytönen, Timo

2015-04-01

348

Music–color associations are mediated by emotion  

PubMed Central

Experimental evidence demonstrates robust cross-modal matches between music and colors that are mediated by emotional associations. US and Mexican participants chose colors that were most/least consistent with 18 selections of classical orchestral music by Bach, Mozart, and Brahms. In both cultures, faster music in the major mode produced color choices that were more saturated, lighter, and yellower whereas slower, minor music produced the opposite pattern (choices that were desaturated, darker, and bluer). There were strong correlations (0.89 < r < 0.99) between the emotional associations of the music and those of the colors chosen to go with the music, supporting an emotional mediation hypothesis in both cultures. Additional experiments showed similarly robust cross-modal matches from emotionally expressive faces to colors and from music to emotionally expressive faces. These results provide further support that music-to-color associations are mediated by common emotional associations. PMID:23671106

Palmer, Stephen E.; Schloss, Karen B.; Xu, Zoe; Prado-León, Lilia R.

2013-01-01

349

Relationship between Color and Emotion: A Study of College Students  

ERIC Educational Resources Information Center

Ninety-eight college students were asked to indicate their emotional responses to five principle hues (i.e., red, yellow, green, blue, purple), five intermediate hues (i.e., yellow-red, green-yellow, blue-green, purple-blue, and red-purple), and three achromatic colors (white, gray, and black) and the reasons for their choices. The color stimuli…

Kaya, Naz; Epps, Helen H.

2004-01-01

350

Display Device Color Management and Visual Surveillance of Vehicles  

ERIC Educational Resources Information Center

Digital imaging has seen an enormous growth in the last decade. Today users have numerous choices in creating, accessing, and viewing digital image/video content. Color management is important to ensure consistent visual experience across imaging systems. This is typically achieved using color profiles. In this thesis we identify the limitations…

Srivastava, Satyam

2011-01-01

351

Chest Color and Social Status in Male Geladas (Theropithecus gelada)  

E-print Network

Chest Color and Social Status in Male Geladas (Theropithecus gelada) Thore J. Bergman & Lucy Ho & Jacinta C. Beehner Received: 27 March 2009 /Accepted: 19 August 2009 # Springer Science + Business Media contest or benefits associated with a specific mate choice. Here, we investigate whether a colored patch

352

Color Burst  

NSDL National Science Digital Library

This lesson will help students gain experience in asking questions and conducting inquiry by exploring the separation of colors in water and other solvents; and to communicate and share findings of student investigations. The lesson uses a technique called paper chromatography, which is demonstrated using water, ink, and a coffee filter. Scientists use chromatography frequently to separate and identify the component parts of a mixture. This lesson will help young students gain experience in conducting simple investigations of their own while working in small groups.

353

Cognitive aspects of color  

NASA Astrophysics Data System (ADS)

This report surveys cognitive aspects of color in terms of behavioral, neuropsychological, and neurophysiological data. Color is usually defined as psychophysical color or as perceived color. Behavioral data on categorical color perception, absolute judgement of colors, color coding, visual search, and visual awareness refer to the more cognitive aspects of color. These are of major importance in visual synthesis and spatial organization, as already shown by the Gestalt psychologists. Neuropsychological and neurophysiological findings provide evidence for an interrelation between cognitive color and spatial organization. Color also enhances planning strategies, as has been shown by studies on color and eye movements. Memory colors and the color- language connections in the brain also belong among the cognitive aspects of color.

Derefeldt, Gunilla A. M.; Menu, Jean-Pierre; Swartling, Tiina

1995-04-01

354

Discovery of gynoecium color polymorphism in an aquatic plant.  

PubMed

Flower color polymorphism exhibited by natural populations provides an opportunity for understanding the evolutionary mechanisms contributing to the diversity of floral morphology. However, little is known about the color polymorphism of female organs in flowering plants. Here we report gynoecium color polymorphism in Butomus umbellatus (Butomaceae), an emergent, aquatic monocot. Populations from Mishan, northeastern China comprised two morphs; gynoecia are either pink, as observed in other areas, or white. We measured floral traits and female fecundity in the two gynoecium color morphs in the field. There was no significant difference in plant height, pedicel length, and flower size including petal, sepal and gynoecium between the two morphs, but plants with pink gynoecia had wider inflorescence stalks, larger inner whorl anthers and produced more pollen and ovules than those with white gynoecia. Correspondingly, we found that seed production was significantly higher in the pink than in the white morph. This new finding suggested selection against white gynoecia in part because of low fecundity, consistent with the rarity of the white gynoecium morph in this species. PMID:18924283

Huang, Shuang-Quan; Tang, Xiao-Xin

2008-09-01

355

First flowering dates and flowering periods of prairie plants at Woodworth, North Dakota  

USGS Publications Warehouse

We recorded flowering events for 97 species of prairie plants for 2-6 years near Woodworth, ND. Earliest and latest flower initiation dates varied by year. Temperature seemed much more important than precipitation in influencing phenology of species that bloom from late March through May, but no strong climatic effect was evident for plants that bloom later in the growing season.

Callow, J.M.; Kantrud, H.A.; Higgins, K.F.

1992-01-01

356

THE EFFECT OF 6BENZYLADENINE ON Astilbe ? arendsii ARENDS 'AMETHYST' FLOWERING CULTIVATED FOR CUT FLOWERS  

Microsoft Academic Search

The effect of benzyladenine on Astilbe ? arendsii Arends flowering was deter- mined. The cultivation of Astilbe ? arendsii in an unheated plastic tunnel reduces the in- florescence yield in the first and second year of flowering as compared to the field, but in- creases the fresh weight and lenght of inflorescence stems.

Elbieta Pogroszewska; Patrycja Sadkowska

357

Learning About Color  

NSDL National Science Digital Library

In this project, students will learn about primary, secondary, and complementary colors. Students will also learn about warm & cool colors, along with tints & shades. Lastly, they will create an optical illusion using complimentary colors. INTRODUCTION: Welcome students! Begin by watching this fun video about colors. LEARNING ABOUT COLOR: Now, that you've had an introduction to colors, lets play a little game! Click on the link below. Carmine s Introduction to Color Awesome! Click on the links below ...

Whitni Erickson

2009-04-18

358

Color Theory for Design  

NSDL National Science Digital Library

This lesson will introduce students to color theory with a focus on the use of color in digital design. Students will discover the color wheel, and color harmonies. Color is a very powerful tool in design. It can, enhance a message, give an object visual weight and emphasis, and add richness and depth to a design. We can use color to signify data, to draw attention to a particular object, or to set a mood. Color ...

Mr. Jensen

2009-10-04

359

Flower volatiles, crop varieties and bee responses.  

PubMed

Pollination contributes to an estimated one third of global food production, through both the improvement of the yield and the quality of crops. Volatile compounds emitted by crop flowers mediate plant-pollinator interactions, but differences between crop varieties are still little explored. We investigated whether the visitation of crop flowers is determined by variety-specific flower volatiles using strawberry varieties (Fragaria x ananassa Duchesne) and how this affects the pollination services of the wild bee Osmia bicornis L. Flower volatile compounds of three strawberry varieties were measured via headspace collection. Gas chromatography showed that the three strawberry varieties produced the same volatile compounds but with quantitative differences of the total amount of volatiles and between distinct compounds. Electroantennographic recordings showed that inexperienced females of Osmia bicornis had higher antennal responses to all volatile compounds than to controls of air and paraffin oil, however responses differed between compounds. The variety Sonata was found to emit a total higher level of volatiles and also higher levels of most of the compounds that evoked antennal responses compared with the other varieties Honeoye and Darselect. Sonata also received more flower visits from Osmia bicornis females under field conditions, compared with Honeoye. Our results suggest that differences in the emission of flower volatile compounds among strawberry varieties mediate their attractiveness to females of Osmia bicornis. Since quality and quantity of marketable fruits depend on optimal pollination, a better understanding of the role of flower volatiles in crop production is required and should be considered more closely in crop-variety breeding. PMID:23977347

Klatt, Björn K; Burmeister, Carina; Westphal, Catrin; Tscharntke, Teja; von Fragstein, Maximilian; von Fragstein, Maximillian

2013-01-01

360

Flower Volatiles, Crop Varieties and Bee Responses  

PubMed Central

Pollination contributes to an estimated one third of global food production, through both the improvement of the yield and the quality of crops. Volatile compounds emitted by crop flowers mediate plant-pollinator interactions, but differences between crop varieties are still little explored. We investigated whether the visitation of crop flowers is determined by variety-specific flower volatiles using strawberry varieties (Fragaria x ananassa Duchesne) and how this affects the pollination services of the wild bee Osmia bicornis L. Flower volatile compounds of three strawberry varieties were measured via headspace collection. Gas chromatography showed that the three strawberry varieties produced the same volatile compounds but with quantitative differences of the total amount of volatiles and between distinct compounds. Electroantennographic recordings showed that inexperienced females of Osmia bicornis had higher antennal responses to all volatile compounds than to controls of air and paraffin oil, however responses differed between compounds. The variety Sonata was found to emit a total higher level of volatiles and also higher levels of most of the compounds that evoked antennal responses compared with the other varieties Honeoye and Darselect. Sonata also received more flower visits from Osmia bicornis females under field conditions, compared with Honeoye. Our results suggest that differences in the emission of flower volatile compounds among strawberry varieties mediate their attractiveness to females of Osmia bicornis. Since quality and quantity of marketable fruits depend on optimal pollination, a better understanding of the role of flower volatiles in crop production is required and should be considered more closely in crop-variety breeding. PMID:23977347

Klatt, Björn K.; Burmeister, Carina; Westphal, Catrin; Tscharntke, Teja; von Fragstein, Maximillian

2013-01-01

361

Divergence of flowering genes in soybean.  

PubMed

Soybean genome sequences were blasted with Arabidopsis thaliana regulatory genes involved in photoperioddependent flowering. This approach enabled the identification of 118 genes involved in the flowering pathway. Two genome sequences of cultivated (Williams 82) and wild (IT182932) soybeans were employed to survey functional DNA variations in the flowering-related homologs. Forty genes exhibiting nonsynonymous substitutions between G. max and G. soja were catalogued. In addition, 22 genes were found to co-localize with QTLs for six traits including flowering time, first flower, pod maturity, beginning of pod, reproductive period, and seed filling period. Among the genes overlapping the QTL regions, two LHY/CCA1 genes, GI and SFR6 contained amino acid changes. The recently duplicated sequence regions of the soybean genome were used as additional criteria for the speculation of the putative function of the homologs. Two duplicated regions showed redundancy of both flowering-related genes and QTLs. ID 12398025, which contains the homeologous regions between chr 7 and chr 16, was redundant for the LHY/CCA1 and SPA1 homologs and the QTLs. Retaining of the CRY1 gene and the pod maturity QTLs were observed in the duplicated region of ID 23546507 on chr 4 and chr 6. Functional DNA variation of the LHY/CCA1 gene (Glyma07g05410) was present in a counterpart of the duplicated region on chr 7, while the gene (Glyma16g01980) present in the other portion of the duplicated region on chr 16 did not show a functional sequence change. The gene list catalogued in this study provides primary insight for understanding the regulation of flowering time and maturity in soybean. PMID:23107921

Kim, Moon Young; Shin, Jin Hee; Kang, Yang Jae; Shim, Sang Rea; Lee, Suk-Ha

2012-11-01

362

How Happiness Affects Choice  

E-print Network

Consumers want to be happy, and marketers are increasingly trying to appeal to consumers’ pursuit of happiness. However, the results of six studies reveal that what happiness means varies, and consumers’ choices reflect ...

Mogilner, Cassie

363

Flower power: Tree flowering phenology as a settlement cue for migrating birds  

USGS Publications Warehouse

1. Neotropical migrant birds show a clear preference for stopover habitats with ample food supplies; yet, the proximate cues underlying these decisions remain unclear. 2. For insectivorous migrants, cues associated with vegetative phenology (e.g. flowering, leaf flush, and leaf loss) may reliably predict the availability of herbivorous arthropods. Here we examined whether migrants use the phenology of five tree species to choose stopover locations, and whether phenology accurately predicts food availability. 3. Using a combination of experimental and observational evidence, we show migrant populations closely track tree phenology, particularly the flowering phenology of honey mesquite (Prosopis glandulosa), and preferentially forage in trees with more flowers. Furthermore, the flowering phenology of honey mesquite reliably predicts overall arthropod abundance as well as the arthropods preferred by migrants for food. 4. Together, these results suggest that honey mesquite flowering phenology is an important cue used by migrants to assess food availability quickly and reliably, while in transit during spring migration. ?? 2008 The Authors.

McGrath, L.J.; van Riper, Charles, III; Fontaine, J.J.

2009-01-01

364

Factors Influencing Job Choice  

Microsoft Academic Search

This research sets out a Perceptual-Judgemental-Reinforcement approach to job choice under conditions of complexity and uncertainty.\\u000a It investigates the claim that job choices are based on seven implicit factors: such as the specific size of the occupation,\\u000a the proportion of employees working full-time, the earnings, the job prospects, gender dominance in an occupation, the level\\u000a of unemployment in the occupation

James A. Athanasou

2003-01-01

365

Adolescent Contraceptive Method Choices  

Microsoft Academic Search

This article analyzes determinants of contraceptive method choices among adolescent women in the United States. By using data\\u000a from the 1982 National Survey of Family Growth, we examine factors that differentiate users of various methods early in the\\u000a sexual careers of teenaged women. We find that patterns of method choice not only vary by race and region within the United

Joan R. Kahn; Ronald R. Rindfuss; David K. Guilkey

1990-01-01

366

Flowering time control in European winter wheat  

PubMed Central

Flowering time is an important trait in wheat breeding as it affects adaptation and yield potential. The aim of this study was to investigate the genetic architecture of flowering time in European winter bread wheat cultivars. To this end a population of 410 winter wheat varieties was evaluated in multi-location field trials and genotyped by a genotyping-by-sequencing approach and candidate gene markers. Our analyses revealed that the photoperiod regulator Ppd-D1 is the major factor affecting flowering time in this germplasm set, explaining 58% of the genotypic variance. Copy number variation at the Ppd-B1 locus was present but explains only 3.2% and thus a comparably small proportion of genotypic variance. By contrast, the plant height loci Rht-B1 and Rht-D1 had no effect on flowering time. The genome-wide scan identified six QTL which each explain only a small proportion of genotypic variance and in addition we identified a number of epistatic QTL, also with small effects. Taken together, our results show that flowering time in European winter bread wheat cultivars is mainly controlled by Ppd-D1 while the fine tuning to local climatic conditions is achieved through Ppd-B1 copy number variation and a larger number of QTL with small effects. PMID:25346745

Langer, Simon M.; Longin, C. Friedrich H.; Würschum, Tobias

2014-01-01

367

Disruptive Coloration  

NSDL National Science Digital Library

Most animals are patterned. While some markings may serve as an advertisement, many appear to function in concealment. Because of the principal way in which they seem to function, such markings are often termed disruptive coloration . Although there are a number of characteristics that may influence the effectiveness of markings in disruption; this study will only focus on two aspects: (1) the effectiveness of the position of markings in blurring or enhancing outline, and (2) the degree to which strongly contrasting markings may interfere with or aid recognition. In regard to the former, it must be kept in mind that the profile changes with change in viewing angle. Thus the pattern seen in relation to the profile most commonly presented to predator (or prey) is of most interest to us here.

David Ipsen

2009-04-01

368

COLORS Magazine  

NSDL National Science Digital Library

COLORS Magazine was willed into existence in 1991 by photographer Oliviero Toscani and art director Tibor Kalman. Its goal was simple: "to show the world to the world.â?ť The publication looks at social issues around the world through thoughtful prose and meaningful visuals. Visitors can click on the Stories tab to click through a visual field of photos that lead to such stories as military service in South Korea and cuts to public spending in the United Kingdom. The Notebooks area brings together commentaries from all over the world as part of a collaboration with Reporters sans Frontieres. The Projects area contains links to special issues and projects, such as the News Machine that "churns your tweets through different media filters.â?ť Interested users can learn about obtaining a print subscription or explore the corresponding blog.

369

Late-Flowering Species are Sensitive to Warming  

NASA Astrophysics Data System (ADS)

Phenological advancement is one of the most prevalent responses of vegetation to warming. The prevailing view is that that early flowering species are particularly sensitive warming, with greater phenological advancement per °C warming relative to later flowering species. However, we observed a three to four month advancement of late flowering species to the extreme warmth of 2012, which motivated us to ask quantitatively whether late flowering species are indeed less sensitive to warming. We focused on responses to inter-annual variation in mean monthly, seasonal, and annual temperatures, using species for which we have ?10 observations of first flowering near Manhattan, KS between 1891 and 2012 (n = 259). As many other studies have found, early flowering species advanced flowering with warmer temperatures during the year preceding flowering, while late flowering species appeared insensitive to warming during the year preceding flowering. At the seasonal time scale, however, both early and late flowering species responded similarly to spring warming, while late flowering species delayed flowering in response to summer warmth. This divergent response created the illusion that later flowering species were insensitive to temperatures during the year preceding flowering. When absolute values of sensitivities to temperature were summed across months, late flowering species exhibited greater sensitivity to temperature than early flowering species. Late-flowering species were also the most sensitive to variation in precipitation and advanced flowering when summers were wet. We therefore speculate that flowering for late species is delayed by warm, dry summers because both warmth and dryness exacerbate plant water stress and delay growth. Furthermore, warm spring temperatures might allow both early and late flowering species to more quickly attain size or developmental requirements for flowering. Advanced flowering in 2012 provides an extreme example of some typically late species reaching these requirements prior to summer. Based on this analysis, we urge caution in analyses of plant sensitivity to warming. Our findings cast doubt on whether late species are indeed less sensitive to warming or generally delay flowering in response to warming and highlight the need to better incorporate the timing of climate variability when predicting how climate change will affect the timing of life events.

Carter, D. L.; VanderWeide, B. L.

2012-12-01

370

Colors and Shapes  

NSDL National Science Digital Library

How do you name things by color and shape? Lets learn about shapes and colors! 1. Watch this Color Video 2. Play this Color Game 3. Complete this Color Page 4. Watch this Shape Video 5. Watch this Shape Video2 6. Play this Shape Game 7. ...

Ms.Campbell

2012-04-04

371

Similarity of Color Images  

Microsoft Academic Search

We describe two new color indexing techniques. The first one is a more robust version of thecommonly used color histogram indexing. In the index we store the cumulative color histograms.The L 1 -, L 2 -, or L1 -distance between two cumulative color histograms can be used to define asimilarity measure of these two color distributions. We show that while

Markus A. Stricker; Markus Orengo

1995-01-01

372

Disappearing Colors Crayola Supplies  

E-print Network

· · Social Studies Visual Arts · · Why Experiment with color perception by making your own color filter on the lens color. 2. Design your own experiment. Draw patterns of lines and shapes using Crayola to see how looking through different colored plastic wrap affects your perception of colorful patterns

Zanibbi, Richard

373

Paper roughness and the color gamut of color laser images  

NASA Astrophysics Data System (ADS)

Common experience indicates the quality of a printed image depends on the choice of the paper used in the printing process. In the current report, we have used a recently developed device called a micro-goniophotometer to examine toner on a variety of substrates fused to varying degrees. The results indicate that the relationship between the printed color gamut and the topography of the substrate paper is a simple one for a color electrophotographic process. If the toner is fused completely to an equilibrium state with the substrate paper, then the toner conforms to the overall topographic features of the substrate. For rougher papers, the steeper topographic features are smoothed out by the toner. The maximum achievable color gamut is limited by the topographic smoothness of the resulting fused surface. Of course, achieving a fully fused surface at a competitive printing rate with a minimum of power consumption is not always feasible. However, the only significant factor found to limit the maximum state of fusing and the ultimate achievable color gamut is the smoothness of the paper.

Arney, J. S.; Spampata, Michelle; Farnand, Susan; Oswald, Tom; Chauvin, Jim

2007-01-01

374

Tiger cubs and little flowers.  

PubMed

Short vignettes are related to show the conditions for girls and women in Morocco. Descriptions are given for child labor, literacy, the government's education campaign, youth group efforts to enhance family planning (FP) knowledge, the impact of FP outreach in rural areas, and unmarried mothers. In Morocco's cities, young boys can be seen hawking cigarettes and working in market stalls; in the countryside, boys herd goats or do other farm work. In rural areas girls are hidden by having them perform work around the house or on the farm primarily indoors. Women are supervised by women. 54% work as maids and 39% are apprentices in carpet factories. Parents prefer to have their daughters working and consider it protection from mischief as well as needed income. Only 60% of girls are enrolled in primary school vs. 80% of the boys. In rural areas, only 44% of girls are enrolled, and 20% stay to complete their primary education, while 76% of boys enroll and 63% complete primary school. Literacy of women has an effect on the ability to accurately take birth control pills. All ages of women gather at schools in the evening for lessons in reading and writing in a program supported by the King. Women are pleased with their success in just learning how to write their own names. Television advertisements promote sending children to school, as another part of the Ministry of Education's campaign to increase girl's educational status. There are still not enough schools; many schools are double shift, and communities are building their own schools. Youth clubs, which refer to boys as "tiger cubs" and girls as "little flowers," try to familiarize young people with some basic information about contraception. A traditional midwife relates some problems with girl's education: costs for clothing and supplies, worry about male teachers, and poor role models. In some remote areas, farm families do not send their children to school, because of the distance to schools and the need for farm workers. Husbands divorce wives for not producing children, and turn away FP workers who knock on their doors. Unmarried mothers aged 14-19 are usually illiterate and poor and cannot afford abortion. Orphanages are full. FP is practiced only by the married, after having proven their fertility. PMID:12318178

1993-01-01

375

Preference for oddity: uniqueness heuristic or hierarchical choice process?  

PubMed

Traditional economic theories assume decision makers in multialternative choice tasks "assign" a value to each option and then express rational preferences. Here, I report an apparent violation of such rationality in gray jays (Perisoreus canadensis). I tested the jays' preference in a quaternary choice task where three options were the same color and the fourth option was a different color. All options offered an identical food reward and so the strictly rational expectation was that subjects would choose the odd-colored option in 25% of choices. In clear disagreement, every subject chose the odd option more frequently than expected. I speculate as to how this surprising preference for oddity might have been ecologically rational: by using a unique-choice heuristic, the jays might have been able to bypass a deliberative phase of the decision process and devote more attention to scanning for predators. Alternatively, it is conceivable that the jays did not prefer oddity per se. Instead, they might have used a hierarchical process, assigning options to color categories and then choosing between categories. If so, their behavior matches expectation after all (on average, subjects chose the odd option 50% of the time). It should be straightforward to test these competing hypotheses. The current results can be viewed as a new example of how simple mechanisms sometimes produce economically puzzling yet ecologically rational decision making. PMID:18528719

Waite, Thomas A

2008-10-01

376

Female American goldfinches use carotenoid-based bill coloration to signal status  

Microsoft Academic Search

Interest in female ornamentation has burgeoned recently, and evidence suggests that carotenoid-based female coloration may function as a mate-choice signal. However, the possibility that females may signal status with coloration has been all but ignored. Bill coloration of female American goldfinches (Spinus tristis) changes seasonally, from dull gray in winter to bright orange in the breeding season. We conducted a

Troy G. Murphy; Malcolm F. Rosenthal; Robert Montgomerie; Keith A. Tarvinc

2009-01-01

377

2009 Virginia Polytechnic Institute and State University 2901-1041 Virginia Cooperative Extension programs and employment are open to all, regardless of race, color, national origin, sex, religion, age, disability, political beliefs, sexual orientation, o  

E-print Network

and then berries turn black. Fall foliage color varies with cultivar and is usually an attractive dark red/purple programs and employment are open to all, regardless of race, color, national origin, sex, religion, age viburnum. Flowers are followed by bright red berries in fall. Red berry color persists for a few weeks

Liskiewicz, Maciej

378

Orchid flowers tolerance to gamma-radiation  

NASA Astrophysics Data System (ADS)

Cut flowers are fresh goods that may be treated with fumigants such as methyl bromide to meet the needs of the quarantine requirements of importing countries. Irradiation is a non-chemical alternative to substitute the methyl bromide treatment of fresh products. In this research, different cut orchids were irradiated to examine their tolerance to gamma-rays. A 200 Gy dose did inhibit the Dendrobium palenopsis buds from opening, but did not cause visible damage to opened flowers. Doses of 800 and 1000 Gy were damaging because they provoked the flowers to drop from the stem. Cattleya irradiated with 750 Gy did not show any damage, and were therefore eligible for the radiation treatment. Cymbidium tolerated up to 300 Gy and above this dose dropped prematurely. On the other hand, Oncydium did not tolerate doses above 150 Gy.

Kikuchi, Olivia Kimiko

2000-03-01

379

Early Cretaceous lineages of monocot flowering plants  

PubMed Central

The phylogeny of flowering plants is now rapidly being disclosed by analysis of DNA sequence data, and currently, many Cretaceous fossils of flowering plants are being described. Combining molecular phylogenies with reference fossils of known minimum age makes it possible to date the nodes of the phylogenetic tree. The dating may be done by counting inferred changes in sequenced genes along the branches of the phylogeny and calculating change rates by using the reference fossils. Plastid DNA rbcL sequences and eight reference fossils indicate that ?14 of the extant monocot lineages may have diverged from each other during the Early Cretaceous >100 million years B.P. The lineages are very different in size and geographical distribution and provide perspective on flowering plant evolution. PMID:10759567

Bremer, Kĺre

2000-01-01

380

How to perform RT-qPCR accurately in plant species? A case study on flower colour gene expression in an azalea (Rhododendron simsii hybrids) mapping population  

PubMed Central

Background Flower colour variation is one of the most crucial selection criteria in the breeding of a flowering pot plant, as is also the case for azalea (Rhododendron simsii hybrids). Flavonoid biosynthesis was studied intensively in several species. In azalea, flower colour can be described by means of a 3-gene model. However, this model does not clarify pink-coloration. The last decade gene expression studies have been implemented widely for studying flower colour. However, the methods used were often only semi-quantitative or quantification was not done according to the MIQE-guidelines. We aimed to develop an accurate protocol for RT-qPCR and to validate the protocol to study flower colour in an azalea mapping population. Results An accurate RT-qPCR protocol had to be established. RNA quality was evaluated in a combined approach by means of different techniques e.g. SPUD-assay and Experion-analysis. We demonstrated the importance of testing noRT-samples for all genes under study to detect contaminating DNA. In spite of the limited sequence information available, we prepared a set of 11 reference genes which was validated in flower petals; a combination of three reference genes was most optimal. Finally we also used plasmids for the construction of standard curves. This allowed us to calculate gene-specific PCR efficiencies for every gene to assure an accurate quantification. The validity of the protocol was demonstrated by means of the study of six genes of the flavonoid biosynthesis pathway. No correlations were found between flower colour and the individual expression profiles. However, the combination of early pathway genes (CHS, F3H, F3'H and FLS) is clearly related to co-pigmentation with flavonols. The late pathway genes DFR and ANS are to a minor extent involved in differentiating between coloured and white flowers. Concerning pink coloration, we could demonstrate that the lower intensity in this type of flowers is correlated to the expression of F3'H. Conclusions Currently in plant research, validated and qualitative RT-qPCR protocols are still rare. The protocol in this study can be implemented on all plant species to assure accurate quantification of gene expression. We have been able to correlate flower colour to the combined regulation of structural genes, both in the early and late branch of the pathway. This allowed us to differentiate between flower colours in a broader genetic background as was done so far in flower colour studies. These data will now be used for eQTL mapping to comprehend even more the regulation of this pathway. PMID:23800303

2013-01-01

381

Pollinator coupling can induce synchronized flowering in different plant species.  

PubMed

Synchronous and intermittent plant reproduction has been identified widely in diverse biomes. While synchronous flowering is normally observed within the same species, different species also flower in synchrony. A well-known example of interspecific synchrony is "general flowering" in tropical rain forests of Southeast Asia. Environmental factors, such as low temperature and drought, have been considered as major trigger of general flowering. However, environmental cues are not enough to explain general flowering because some trees do not flower even when they encounter favorable environmental cues. We propose alternative explanation of general flowering; "pollinator coupling". When species flower synchronously, the elevated pollen and nectar resource may attract increased numbers of generalist pollinators, with a concomitant enhancement of pollination success (facilitation). However, under these circumstances, plants of different species may compete with one another for limited pollinator services, resulting in declines in pollination success for individual species (competition). Here, we present a model describing resource dynamics of individual trees serviced by generalist pollinators. We analyze combinations of conditions under which plants reproduce intermittently with synchronization within species, and/or (sometimes) between different species. We show that plants synchronize flowering when the number of pollinators attracted to an area increases at an accelerating rate with increasing numbers of flowers. In this case, facilitation of flowering by different species exceeds the negative influence of interspecific plant competition. We demonstrate mathematically that co-flowering of different species occurs under a much narrower range of circumstances than intraspecific co-flowering. PMID:20800600

Tachiki, Yuuya; Iwasa, Yoh; Satake, Akiko

2010-11-21

382

Bilabiate Flowers: The Ultimate Response to Bees?  

PubMed Central

Background and Aims Bilabiate flowers have evolved in many lineages of the angiosperms, thus representing a convincing example of parallel evolution. Similar to keel blossoms, they have obviously evolved in order to protect pollen against pollen-collecting bees. Although many examples are known, a comprehensive survey on floral diversity and functional constraints of bilabiate flowers is lacking. Here, the concept is widened and described as a general pattern. Methods The present paper is a conceptional review including personal observations of the authors. To form a survey on the diversity of bilabiate blossoms, a search was made for examples across the angiosperms and these were combined with personal observations collected during the last 25 years, coupled with knowledge from the literature. New functional terms are introduced that are independent of morphological and taxonomic associations. Key Results Bilabiate constructions occur in at least 38 angiosperm families. They are characterized by dorsiventral organization and dorsal pollen transfer. They are most often realised on the level of a single flower, but may also be present in an inflorescence or as part of a so-called ‘walk-around flower’. Interestingly, in functional terms all nototribic blossoms represent bilabiate constructions. The great majority of specialized bee-flowers can thus be included under bilabiate and keel blossoms. The syndrome introduced here, however, also paves the way for the inclusion of larger animals such as birds and bats. The most important evolutionary trends appear to be in the saving of pollen and the precision of its transfer. With special reference to the Lamiales, selected examples of bilabiate flowers are presented and their functional significance is discussed. Conclusions Bilabiate blossoms protect their pollen against pollen-collecting bees and at the same time render their pollination more precisely. The huge diversity of realised forms indicate the high selection pressure towards the bilabiate syndrome. As bees are very inventive, however, bilabiate constructions will not represent the ultimate response to bees. PMID:17652341

Westerkamp, Christian; Claßen-Bockhoff, Regine

2007-01-01

383

Predicting affective choice.  

PubMed

Affect is increasingly recognized as central to decision making. However, it is not clear whether affect can be used to predict choice. To address this issue, we conducted 4 studies designed to create and test a model that could predict choice from affect. In Study 1, we used an image rating task to develop a model that predicted approach-avoidance motivations. This model quantified the role of two basic dimensions of affect--valence and arousal--in determining choice. We then tested the predictive power of this model for two types of decisions involving images: preference based selections (Study 2) and risk-reward trade-offs (Study 3). In both cases, the model derived in Study 1 predicted choice and outperformed competing models drawn from well-established theoretical views. Finally, we showed that this model has ecological validity: It predicted choices between news articles on the basis of headlines (Study 4). These findings have implications for diverse fields, including neuroeconomics and judgment and decision making. PMID:22924884

Suri, Gaurav; Sheppes, Gal; Gross, James J

2013-08-01

384

Energy Choices Game  

NSDL National Science Digital Library

Use this board game to introduce the concepts of energy use in our lives and the very real impact that personal choices can have on our energy consumption, energy bills and fuel supply. The game begins as students select cards that define their modes of transportation and home design. The players roll dice and move around the board, landing on "choice" or "situation" blocks and selecting cards that describe consumer choices and real-life events that impact their energy consumption and annual energy bills. As the players pass gasoline stations or energy bill gates, they must pay annual expenses as defined by their original cards, with amounts altered by the choices they've made along the way. Gasoline cards are collected to represent total consumption. Too many gas-guzzling vehicles can result in total depletion of their gasoline supply – at which point everyone must walk or ride the bus. At the end of the game, the players count their remaining dollars to determine the winner. Discussion questions probe the students to interpret what choices they made and which situations they encountered had the most impact on their energy consumption and energy bills. All game board, card and money files are available online free of charge.

Office of Educational Partnerships,

385

Skin color - patchy  

MedlinePLUS

Patchy skin color is areas where the skin color is irregular. Mottling or mottled skin refers to blood vessel changes in ... in the skin cells that gives skin its color Growth of bacteria or other organisms on the ...

386

Color Blindness Simulations  

MedlinePLUS

Color blindness Simulations Normal Color Vision Deuteranopia Color blindness marked by confusion of purplish red and green Tritanopia A dichromatism in ... and green and reduced sensitivity to monochromatic lights. Simulations created using Image J 1.22d, National Institutes ...

387

Color Perception Optical Illusions  

NSDL National Science Digital Library

This website from eChalk contains optical illusions offering proof that our color perception is strongly influenced by surrounding colors. The site also includes educational games related to optical illusions and color.

388

Development and Application of a Two-Tier Diagnostic Test for High School Students’ Understanding of Flowering Plant Growth and Development  

Microsoft Academic Search

This study involved the development and application of a two-tier diagnostic test measuring students’ understanding of flowering plant growth and development. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students’ misconceptions, and instrument development. Misconception data were collected from interviews and multiple-choice questions with open response answers. The data were

Sheau-Wen Lin

2004-01-01

389

Relationship between Ethylene Evolution and Senescence in Morning-Glory Flower Tissue 1  

PubMed Central

An excised tissue system consisting of corolla rib segments was developed to study the relationship between senescence and ethylene production in morning-glory flowers (Ipomoea tricolor). Such segments, isolated 1 or 2 days (day ?1 or day ?2) before flower opening (day 0) passed through the same developmental phases as did the corresponding tissues of the intact organ. When excised on day ?1 and incubated overnight, the rib segments turned from purple to blue and changed from a slightly curled to a flat configuration. On day 0, these segments rolled up during the afternoon and turned purple again, as did the ribs of an intact corolla; the rolling up coincided with an increased rate of ethylene production. Premature rolling up and associated ethylene evolution were induced by ethylene or propylene treatment. When segments were excised on day ?2 and incubated overnight, there were no changes in color or shape; during day ?1, no spontaneous rolling up and little ethylene evolution occurred. Application of ethylene or propylene to these immature segments elicited rolling up but did not stimulate endogenous ethylene production. Overnight treatment of segments cut on day ?1 with 10?6m benzyladenine markedly retarded spontaneous rolling up and ethylene evolution, although the response to applied ethylene was only slightly slowed. Overnight treatment of segments cut on day ?1 with the ethoxy analog of rhizobitoxine (10?5 to 10?4m) resulted in almost complete (>99%) inhibition of both spontaneous and propylene-induced ethylene evolution. Although spontaneous rolling up was delayed, it was not abolished, and ethylene-induced rolling up was almost unaffected. These data indicate that an ethylene-generating system develops as an integral part of the aging process in flower tissue. Ethylene hastens aging of the flower, but may not play an obligatory role in flower senescence. PMID:16659519

Kende, Hans; Hanson, Andrew D.

1976-01-01

390

Relationship between Ethylene Evolution and Senescence in Morning-Glory Flower Tissue.  

PubMed

An excised tissue system consisting of corolla rib segments was developed to study the relationship between senescence and ethylene production in morning-glory flowers (Ipomoea tricolor). Such segments, isolated 1 or 2 days (day -1 or day -2) before flower opening (day 0) passed through the same developmental phases as did the corresponding tissues of the intact organ. When excised on day -1 and incubated overnight, the rib segments turned from purple to blue and changed from a slightly curled to a flat configuration. On day 0, these segments rolled up during the afternoon and turned purple again, as did the ribs of an intact corolla; the rolling up coincided with an increased rate of ethylene production. Premature rolling up and associated ethylene evolution were induced by ethylene or propylene treatment. When segments were excised on day -2 and incubated overnight, there were no changes in color or shape; during day -1, no spontaneous rolling up and little ethylene evolution occurred. Application of ethylene or propylene to these immature segments elicited rolling up but did not stimulate endogenous ethylene production.Overnight treatment of segments cut on day -1 with 10(-6)m benzyladenine markedly retarded spontaneous rolling up and ethylene evolution, although the response to applied ethylene was only slightly slowed. Overnight treatment of segments cut on day -1 with the ethoxy analog of rhizobitoxine (10(-5) to 10(-4)m) resulted in almost complete (>99%) inhibition of both spontaneous and propylene-induced ethylene evolution. Although spontaneous rolling up was delayed, it was not abolished, and ethylene-induced rolling up was almost unaffected.These data indicate that an ethylene-generating system develops as an integral part of the aging process in flower tissue. Ethylene hastens aging of the flower, but may not play an obligatory role in flower senescence. PMID:16659519

Kende, H; Hanson, A D

1976-04-01

391

Color matching from memory  

Microsoft Academic Search

Short-term color memory of two groups of university students, 20 with prior color coursework, and 20 with no color-related training, was evaluated in four hue categories: yellow, yellow-red, green, and purple. Munsell dimensions of hue, value, and chroma were used to select four target colors and nine distractor colors for each of the targets. Four of the distractor colors differed

Helen H. EPPS; Naz KAYA

392

Colored Shadows Investigation  

NSDL National Science Digital Library

This activity (located on page 3 of the PDF) is a full inquiry investigation into mixing colors with light. Groups of learners will set up colored lights in a darkened room and record the color of shadows cast by each color. They will continue to collect data as they experiment with combinations of multiple colored lights and produce a data table to organize their findings. Relates to linked video, DragonflyTV GPS: Light and Color.

Twin Cities Public Television, Inc.

2006-01-01

393

Genetics of local adaptation in the laboratory: flowering time quantitative trait loci under geographic and seasonal conditions in Arabidopsis.  

PubMed

Flowering time in Arabidopsis thaliana is controlled by a large number of genes and various environmental factors, such as light and temperature. The objective of this study was to identify flowering time quantitative trait loci (QTL) under growth conditions simulating seasonal conditions from native geographic locations. Our growth chambers were set to simulate the spring conditions in Spain and Sweden, with appropriate changes in light color, intensity and day length, as well as temperature and relative humidity. Thus the Sweden-like spring conditions changed more dramatically compared to Spain-like spring conditions across the duration of our experiment. We have used these conditions to map QTL responsible for flowering time in the Kas-1/Col-gl1 recombinant inbred lines (RILs) across two replicate blocks. A linkage map from 96 RILs was established using 119 markers including 64 new SNPs markers. One major QTL, mapping to the FRIGIDA (FRI) locus, was detected on the top of chromosome 4 that showed significant gene x seasonal environment interactions. Three other minor QTL also were detected. One QTL mapping near FLOWERING LOCUS M (FLM) showed an epistatic interaction with the QTL at FRI. These QTLxenvironment and QTL x QTL interactions suggest that subtle ecologically relevant changes in light, temperature, and relative humidity are differentially felt by alleles controlling flowering time and may be responsible for adaptation to regional environments. PMID:17205109

Li, Yan; Roycewicz, Peter; Smith, Evadne; Borevitz, Justin O

2006-01-01

394

Attention mediates the effect of nutrition label information on consumers' choice. Evidence from a choice experiment involving eye-tracking.  

PubMed

In two eye-tracking studies, we explored whether and how attention to nutrition information mediates consumers' choice. Consumers had to select either the healthiest option or a product of their preference within an assortment. On each product a particular label (Choices logo, monochrome GDA label, or color-coded GDA label) communicated the product's nutrient profile. In study 1, participants had to select from 4 products differentiated, in addition to the nutrition information, by flavor (strawberry, muesli, apple, chocolate; varied within participants) and brand (local vs. global, varied between participants). Study 2 further explored brand effect within-participants, and thus only 2 flavors (strawberry, chocolate) were presented within an assortment. Actual choice made, response time and eye movements were recorded. Respondents fixated longer and more often on products with color-coded GDAs label than on products with monochrome GDAs or Choices logo. A health goal resulted in longer and more frequent fixations in comparison to a preference goal. Products with color-coded and monochrome GDAs had the highest likelihood of being chosen, and this effect was related to the attention-getting property of the label (irrespective of brand and flavor effects). The product fixated most had the highest likelihood of being chosen. These results suggest that attention mediates the effect of nutrition labels on choice. PMID:24503332

Bialkova, Svetlana; Grunert, Klaus G; Juhl, Hans Jřrn; Wasowicz-Kirylo, Grazyna; Stysko-Kunkowska, Malgorzata; van Trijp, Hans C M

2014-05-01

395

Cut Flowers and Greenery Import  

E-print Network

Manual Some processes, equipment, and materials described in this manual may be patented. Inclusion in this manual does not constitute permission for use from the patent owner. The use of any patented invention in the performance of the processes described in this manual is solely the responsibility of the user. APHIS does not indemnify the user against liability for patent infringement and will not be liable to the user or to any third party for patent infringement. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400

United States

396

Field methods for sampling and storing nectar from flowers with low nectar volumes  

PubMed Central

Background and Aims Although several methods of sampling and storing floral nectar are available, little information exists on sampling and storing nectar from flowers with low nectar volumes. Methods for sampling and storing nectar from the flowers of species with low floral nectar volumes (<1 µL) were investigated using the flowers of Eucalyptus species. Methods Sampling with microcapillary tubes, blotting up with filter paper, washing and rinsing were compared to determine masses of sugars recovered and differences in sugar ratios. Storage methods included room temperature, refrigeration and freezing treatments; the addition of antimicrobial agents benzyl alcohol or methanol to some of these treatments was also evaluated. Nectar samples were analysed using high-performance liquid chromatography and the masses of sucrose, glucose and fructose in each sample were determined. Key Results Masses of sugars varied significantly among sampling treatments, but the highest yielding methods, rinsing and washing, were not significantly different. A washing time of 1 min was as effective as one of 20 min. Storage trials showed that the sugar concentration measurements of nectar solutions changed rapidly, with the best results achieved for refrigeration with no additive (sucrose and fructose were stable for at least 2 weeks). Sugar ratios, however, remained relatively stable in most treatments and did not change significantly across 4 weeks for the methanol plus refrigerator and freezing treatments, and 2 weeks for the refrigeration treatment with no additive. Conclusions Washing is recommended for nectar collection from flowers with low nectar volumes in the field (with the understanding that one wash underestimates the amounts of sugars present in a flower), as is immediate analysis of sugar mass. In view of the great variation in results depending on nectar collection and storage methods, caution should be exercised in their choice, and their accuracy should be evaluated. The use of pulsed amperometric detection, more specific than refractive index detection, may improve the accuracy of nectar sugar analysis. PMID:19074446

Morrant, D. S.; Schumann, R.; Petit, S.

2009-01-01

397

Mutation in TERMINAL FLOWER1 reverses the photoperiodic requirement for flowering in the wild strawberry Fragaria vesca.  

PubMed

Photoperiodic flowering has been extensively studied in the annual short-day and long-day plants rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana), whereas less is known about the control of flowering in perennials. In the perennial wild strawberry, Fragaria vesca (Rosaceae), short-day and perpetual flowering long-day accessions occur. Genetic analyses showed that differences in their flowering responses are caused by a single gene, SEASONAL FLOWERING LOCUS, which may encode the F. vesca homolog of TERMINAL FLOWER1 (FvTFL1). We show through high-resolution mapping and transgenic approaches that FvTFL1 is the basis of this change in flowering behavior and demonstrate that FvTFL1 acts as a photoperiodically regulated repressor. In short-day F. vesca, long photoperiods activate FvTFL1 mRNA expression and short days suppress it, promoting flower induction. These seasonal cycles in FvTFL1 mRNA level confer seasonal cycling of vegetative and reproductive development. Mutations in FvTFL1 prevent long-day suppression of flowering, and the early flowering that then occurs under long days is dependent on the F. vesca homolog of FLOWERING LOCUS T. This photoperiodic response mechanism differs from those described in model annual plants. We suggest that this mechanism controls flowering within the perennial growth cycle in F. vesca and demonstrate that a change in a single gene reverses the photoperiodic requirements for flowering. PMID:22566495

Koskela, Elli A; Mouhu, Katriina; Albani, Maria C; Kurokura, Takeshi; Rantanen, Marja; Sargent, Daniel J; Battey, Nicholas H; Coupland, George; Elomaa, Paula; Hytönen, Timo

2012-07-01

398

Skin segmentation using color pixel classification: analysis and comparison.  

PubMed

This paper presents a study of three important issues of the color pixel classification approach to skin segmentation: color representation, color quantization, and classification algorithm. Our analysis of several representative color spaces using the Bayesian classifier with the histogram technique shows that skin segmentation based on color pixel classification is largely unaffected by the choice of the color space. However, segmentation performance degrades when only chrominance channels are used in classification. Furthermore, we find that color quantization can be as low as 64 bins per channel, although higher histogram sizes give better segmentation performance. The Bayesian classifier with the histogram technique and the multilayer perceptron classifier are found to perform better compared to other tested classifiers, including three piecewise linear classifiers, three unimodal Gaussian classifiers, and a Gaussian mixture classifier. PMID:15628277

Phung, Son Lam; Bouzerdoum, Abdesselam; Chai, Douglas

2005-01-01

399

The application study on building materials with computer color quantification system  

NASA Astrophysics Data System (ADS)

The first impression of any building to a person is its exterior and decoration, and therefore the quality of decoration project shows the more important position in building project. A lot of projects produce quality problem because of the material color difference, which exists universally at the common project, and is often found at the high-grade decoration; therefore, how to grasp and control the color change of building materials, and carry out color quantification, it has the very important meaning. According to the color theory, a computer vision system used in color quantification measurement is established, the standard illuminant A is selected as the light source. In order to realize the standardization of color evaluation, the mutual conversion between RGB and XYZ color space is studied, which is realized by the BP network. According to the colorimetry theory, the computer program is compiled in order to establish the software system, and realize the color quantitative appraisement in whole color gamut. LCH model is used at quantifying the color of building materials, and L *a *b * model is used at comparing the color change. If the wooden floor is selected and laid improperly during family fitment, it is easy to present "flower face". The color also arises greater discrepancy using the laths of same tree. We can give the laying scheme using the color quantification system; at the same time, the color difference problem laying stone materials is also studied in this paper, and the solution scheme has been given using this system.

Li, Zhendong; Yu, Haiye; Li, Hongnan; Zhao, Hongxia

2006-01-01

400

Honeybees mark with scent and reject recently visited flowers  

Microsoft Academic Search

Experimental evidence is reported for flower-marking by honeybees (Apis mellifera ligustica) while they were foraging on an artificial patch of flowers yielding a continuous and equal flow of sucrose solution. Honeybees marked with scent and rejected all recently visited and nectar-depleted flowers. The short fade-out time of this scent allowed discrimination of flowers that temporarily provided no food. The repellent

Martin Giurfa; Josué A. Núńez

1992-01-01

401

FoodFit: A Web Application to Illustrate Healthier Food and Physical Activity Choices  

E-print Network

FoodFit: A Web Application to Illustrate Healthier Food and Physical Activity Choices Meriyan Eren their lifestyles to include healthier food choices and more frequent physical activities. Lack of motivation your diet with physical activities - Familiar nutrition facts label, colorful bar plots and face

Toronto, University of

402

Variation of L-DOPA in the leaf and flower tissues of seven faba bean accessions with different flower colors  

Technology Transfer Automated Retrieval System (TEKTRAN)

Faba bean (Vicia faba L.) has been selected to adapt to a wide range of environments worldwide and is grown for different end-uses such as food, feed, forage and green manure. Particularly noteworthy in faba bean is the medicinally important component L-3,4-dihydroxy phenylalanine (L-DOPA), the majo...

403

Flower biology and biologically-based integrated fire blight management  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fire blight infection is generally initiated in flowers, and thus, research has been directed to the biology and microbial ecology of flowers as related to this disease. In addition to investigations involving apple and pear flowers, Manchurian crab apple (Malus manchurica), closely related to appl...

404

77 FR 25060 - Flower Garden Banks National Marine Sanctuary Regulations  

Federal Register 2010, 2011, 2012, 2013, 2014

...100222109-2171-02] RIN 0648-AY35 Flower Garden Banks National Marine Sanctuary Regulations AGENCIES...amending the regulations for Flower Garden Banks National Marine Sanctuary to improve vessel...available upon request to Flower Garden Banks National Marine Sanctuary, 4700...

2012-04-27

405

Induction of precocious flowering in grapevine seedlings by growth regulators  

E-print Network

Induction of precocious flowering in grapevine seedlings by growth regulators C. SRINIVASAN M. G ABSTRACT Grapevine, Induction to flower, Growth substances, CCC, Accelerating generations. Seedlings of Vitis vinifera, cvs Cabernet Sauvignon and Muscat Hamburg were induced to flower within 4 weeks

Boyer, Edmond

406

Selenium accumulation in flowers and its effects on pollination  

E-print Network

Selenium accumulation in flowers and its effects on pollination 1 Colin F. Quinn1 , Christine N floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant. · Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-sel- enocysteine (Me

407

Evaluation of Transportation Practices in the California Cut Flower Industry  

E-print Network

Page | 1 Evaluation of Transportation Practices in the California Cut Flower Industry Christine, California's share of the national cut flower market has decreased from 64 percent to 20 percent. California the California cut flower industry's current transportation practices and investigates the feasibility and cost

Dessouky, Maged

408

Modulation of germination, elongation growth and flowering time in plants  

E-print Network

Modulation of germination, elongation growth and flowering time in plants Reference Number B69259 growth and flowering time in plants are modulated by modifying the activity of genes/ proteins. · Plants with reduced/depleted gene function germinate faster and flower ear- lier than the wild type. · Plants over

409

PAF1-complex-mediated histone methylation of FLOWERING  

E-print Network

PAF1-complex-mediated histone methylation of FLOWERING LOCUS C chromatin is required for exposure to the cold of winter to flower in the spring) in Arabidopsis thaliana is mainly due to the repression of flowering by relatively high levels of FLC expression. Exposure to prolonged cold attenuates

Raines, Ronald T.

410

The Secret Lives of Roses: The Latin American Flower Industry  

E-print Network

The Secret Lives of Roses: The Latin American Flower Industry By Sheila Jarnes www as the pesticide applicator comes out, the women go in again. The flower beds are still sticky and moist Flower Sales (Worldwide) www.fairtrade.net accessed 2 April 2009 #12;John Nevado of Nevado Roses (A Fair

New Hampshire, University of

411

Surface-based Growth Simulation for Opening Flowers Takashi Ijiri  

E-print Network

Surface-based Growth Simulation for Opening Flowers Takashi Ijiri 1 , Mihoshi Yokoo 1 , Saneyuki motivated method for creating animations of opening flowers. We simulate the development of petals based on the observation that flower opening is mainly caused by cell expansion. We use an elastic triangular mesh

Igarashi, Takeo

412

Rapid Changes in Flowering Time in British Plants  

Microsoft Academic Search

The average first flowering date of 385 British plant species has advanced by 4.5 days during the past decade compared with the previous four decades: 16% of species flowered significantly earlier in the 1990s than previously, with an average advancement of 15 days in a decade. Ten species (3%) flowered significantly later in the 1990s than previously. These data reveal

A. H. Fitter; R. S. R. Fitter

2002-01-01

413

Vernalization: Winter and the Timing of Flowering in Plants  

E-print Network

Vernalization: Winter and the Timing of Flowering in Plants Dong-Hwan Kim,1 Mark R. Doyle,2 Sibum is vernalization, the process by which flowering is promoted as plants sense exposure to the cold temperatures of winter. A requirement for vernalization is an adaptive trait that helps prevent flowering before winter

Amasino, Richard M.

414

Integration of Flowering Signals in Winter-Annual Arabidopsis1  

E-print Network

Integration of Flowering Signals in Winter-Annual Arabidopsis1 Scott D. Michaels2 , Edward affecting flowering time in rapid-cycling accessions of Arabidopsis (Arabidopsis thaliana). Winter-annual Arabidopsis, in contrast, have both a photoperiod and a vernalization requirement for rapid flowering

Raines, Ronald T.

415

7 CFR 318.13-23 - Cut flowers from Hawaii.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Cut flowers from Hawaii. 318.13-23 Section...the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut...with paragraph (b) of this section, cut flowers may be moved interstate from...

2011-01-01

416

75 FR 65256 - Flower Garden Banks National Marine Sanctuary Regulations  

Federal Register 2010, 2011, 2012, 2013, 2014

...100222109-0471-01] RIN 0648-AY35 Flower Garden Banks National Marine Sanctuary...proposes to amend the regulations for the Flower Garden Banks National Marine Sanctuary...2010 from 4 p.m. to 8 p.m. at the Flower Garden Banks National Marine...

2010-10-22

417

A developmental switch sufficient for flower initiation in diverse plants  

Microsoft Academic Search

We have generated transgenic plants in which the flower-meristem-identity gene LEAFY of Arabidopsis is constitutively expressed. LEAFY is sufficient to determine floral fate in lateral shoot meristems of both Arabidopsis and the heterologous species aspen, with the consequence that flower development is induced precociously. Our results also suggest a new level of regulation during flower development, as indicated by the

Detlef Weigel; Ove Nilsson

1995-01-01

418

Experimental control of flower initiation in Weigela japonica  

E-print Network

Experimental control of flower initiation in Weigela japonica M. Bodson Centre de Physiologie, Belgium Introduction Most of the experimental work on the mechanisms controlling flowering are reported and made clear that the leaf processes resulting in the synthe- sis of the flowering stimulus are a major

Paris-Sud XI, Université de

419

Update on Development Photoreceptors and Regulation of Flowering Time1  

E-print Network

Update on Development Photoreceptors and Regulation of Flowering Time1 Chentao Lin* Department Angeles, California 90095­1606 One of the most important environmental factors affecting flowering time (Thomas and Vince-Prue, 1997, and refs. therein). Plants in which flowering occurs or is accelerated

Lin, Chentao

420

CULTURAL PRACTICE STUDIES WITH CUT FLOWERS, 2005 Department of Horticulture  

E-print Network

CULTURAL PRACTICE STUDIES WITH CUT FLOWERS, 2005 H. C. Wien Department of Horticulture Cornell of Planting Study EXECUTIVE SUMMARY: The 2005 cultural practice studies with cut flowers were conducted standard summer varieties. All varieties were inhibited from flowering in the hot summer conditions

Pawlowski, Wojtek

421

Selenium accumulation in flowers and its effects on pollination  

E-print Network

Selenium accumulation in flowers and its effects on pollination Colin F. Quinn1 , Christine N floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant. · Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl- selenocysteine (Me

422

7 CFR 318.13-23 - Cut flowers from Hawaii.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Cut flowers from Hawaii. 318.13-23 Section...the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut...with paragraph (b) of this section, cut flowers may be moved interstate from...

2012-01-01

423

7 CFR 318.13-23 - Cut flowers from Hawaii.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Cut flowers from Hawaii. 318.13-23 Section...the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut...with paragraph (b) of this section, cut flowers may be moved interstate from...

2014-01-01

424

7 CFR 318.13-23 - Cut flowers from Hawaii.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Cut flowers from Hawaii. 318.13-23 Section...the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut...with paragraph (b) of this section, cut flowers may be moved interstate from...

2010-01-01

425

ORIGINAL PAPER Variation in the phenology and abundance of flowering  

E-print Network

ORIGINAL PAPER Variation in the phenology and abundance of flowering by native and exotic plants and abundance of flower pro- duction is important to the reproductive success of angiosperms as well-removal experiment to explore the effects of an invasive exotic flowering plant, Linaria vulgaris, on community

Irwin, Rebecca E.

426

Diversity of Flowering Responses in Wild Arabidopsis thaliana Strains  

E-print Network

Diversity of Flowering Responses in Wild Arabidopsis thaliana Strains Janne Lempe1[ , Sureshkumar multiple environmental cues regulate the transition to flowering in Arabidopsis thaliana, previous studies by their requirement for vernalization (extended winter-like temperatures), which enables rapid flowering under long

Weigel, Detlef

427

7 CFR 318.13-23 - Cut flowers from Hawaii.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Cut flowers from Hawaii. 318.13-23 Section...the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut...with paragraph (b) of this section, cut flowers may be moved interstate from...

2013-01-01

428

NECTAR SUGAR PRODUCTION AND FLOWER VISITORS OF THE BRAMBLE,  

E-print Network

NECTAR SUGAR PRODUCTION AND FLOWER VISITORS OF THE BRAMBLE, RUBUS ELLIPTICUS SMITH (ROSACEAE of Horticulture and Forestry, College of Horticulture, Nauni, Solan, India - 173230 SUMMARY Nectar sugar production in flowers of Rubus ellipticus averaged 6.93 mg/flower at 24 h and the accumulation of the sugar

Paris-Sud XI, Université de

429

Flowering in Crimson Clover as Affected by Planting Date  

Microsoft Academic Search

garding the effects of juvenility on flowering of cool- season annual clovers. Understanding factors that affect flowering of crimson clover (Tri- Most plants flower in response to certain vernaliza- folium incarnatum L.) could improve management decisions to opti- mize utilization by improving season of use. The experiment was a tion and photoperiod requirements. Vernalization is a split-plot randomized complete block

Twain J. Butler; Gerald W. Evers; Mark A. Hussey; Larry J. Ringer

2002-01-01

430

MOLECULAR MECHANISMS OF FLOWER DEVELOPMENT: AN ARMCHAIR GUIDE  

Technology Transfer Automated Retrieval System (TEKTRAN)

An afternoon stroll through an English garden reveals the breathtaking beauty and enormous diversity of flowering plants. The extreme variation of flower morphologies, combined with the relative simplicity of floral structures and the wealth of floral mutants available, has made the flower an excell...

431

Flowering, Capsule and Seed Characteristics in Cuphea  

Technology Transfer Automated Retrieval System (TEKTRAN)

We modeled the flowering and capsule set dynamics, quantified the level of variation in seed characteristics, elucidated the inter-relationships among seed and capsule physical dimensions, and quantified their impact on single seed weight as the main determinant of seed yield in the indeterminate, p...

432

Colour preferences of flower-naive honeybees  

Microsoft Academic Search

Flower-naive honeybees Apis mellifera L. flying in an enclosure were tested for their colour preferences. Bees were rewarded once on an achromatic (grey, aluminium or hardboard), or on a chromatic (ultraviolet) disk. Since naive bees never alighted on colour stimuli alone, a scent was given in combination with colour. Their landings on twelve colour stimuli were recorded. Results after one

M. Giurfa; J. Núńez; L. Chittka; R. Menzel

1995-01-01

433

The oxygen supply to thermogenic flowers.  

PubMed

Thermogenic flowers produce heat by intense respiration, and the rates of O2 consumption (?o2 ) in some species can exceed those of all other tissues of plants and most animals. By exposing intact flowers to a range of O2 pressures (Po2 ) and measuring ?o2 , we demonstrate that the highest respiration rates exceed the capacity of the O2 diffusive pathway and become diffusion limited in atmospheric air. The male florets on the inflorescence of Arum concinnatum have the highest known mass-specific ?o2 and can be severely diffusion limited. Intact spadices of Japanese skunk cabbage Symplocarpus renifolius are diffusion limited in air only when ?o2 is maximal, but not at lower levels. True flowers of the sacred lotus Nelumbo nucifera and the appendix of Arum concinnatum are never diffusion limited in air. ?o2 - Po2 curves are evaluated quantitatively with the 'Regulation Index', a new tool to measure dependence of ?o2 on ambient Po2 , as well as the conventional 'Critical Po2 '. The study also includes measurements of Po2 within thermogenic tissues with O2 -sensitive fibre optics, and reveals that the diffusion pathway is complicated and that O2 can be provided not only from the surface of the tissues but also from the pith of the flower's peduncle. PMID:25256124

Seymour, Roger S; Ito, Kikukatsu; Umekawa, Yui; Matthews, Philip D G; Pirintsos, Stergios Arg

2015-04-01

434

Where Have All the Flowers Gone?  

ERIC Educational Resources Information Center

This article describes an activity for secondary mathematics students using digital imaging on The Geometer's Sketchpad to model polar functions of flowers. The activity presented in the appendix engages students in learning and exploring the polar coordinate system while helping them analyze a real-world situation. By completing this activity,…

Walker, Janet M.

2007-01-01

435

Flowering and apical meristem growth dynamics  

Microsoft Academic Search

The shoot apical meristem generates stem, leaves, and lateral shoot meristems during the entire shoot ontog- eny. Vegetative leaves are generated by the meristem in the vegetative developmental phase, while in the re- productive phase either bracts subtending lateral flower primordia (or paraclades), or perianth and strictly re- productive organs are formed. Meristem growth is fully characterized by the principal

Dorota Kwiatkowska

2010-01-01

436

TWO NEW WHITE-FLOWERED GRIFFINIA SPECIES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Griffinia leucantha and G. cordata, distinct from any other known species of the genus, are described as new from nineteenth century herbarium specimens. Both belong to subg. Griffinia. These Brazilian species lack blue range pigments in the flowers, a characteristic of Griffinia subg. Hyline, but...

437

Oxfordshire Flowers and the Plot Memorial Windows  

Microsoft Academic Search

In NATURE of May 28, 1927, p. 798, in the excellent account of the unveiling of the Wren-Ashmole-Plot Memorial Windows at Oxford, it is said that ``the surrounding wreath is of two Oxfordshire flowers which Plot was the first to recognise as new to the British flora''-Viola palustris and Geranium dissectum.

G. Claridge Druce

1928-01-01

438

Hearts and flowers: Bryophyllum poisoning of cattle.  

PubMed

Findings from natural cases and experiments with cattle emphasise that flowering plants are the most important form of Bryophyllum (Kalanchoe) spp in poisonings in Australia. The main life-threatening lesion is myocardial. The effects on the alimentary tract are less important than was believed previously. B. tubiflorum, B. daigremontianum x B. tubiflorum, B. pinnatum and B. proliferum caused 41 recorded poisoning incidents affecting 379 cattle in Queensland between 1960 and 1984. Poisoning occurred between May and October--the flowering season of these plants. Experimental B. tubiflorum poisoning and natural poisonings produced anorexia, depression, ruminal atony, diarrhoea, heart rate and rhythm abnormalities, dyspnoea and death. Increased plasma concentrations of urea, creatinine and glucose and decreased chloride were measured experimentally. Both natural and experimental cases had myocardial degeneration and necrosis with haemorrhages of the heart and alimentary tract. Cattle with severe dyspnoea had atelectasis and emphysema of the lungs. Some cattle had mild nephrosis. The median lethal doses of B. tubiflorum flowers, roots and leaf plus stem were 0.7, 2.3 and 5.0 g dry matter/kg liveweight respectively (7, 7 and 40 g wet weight/kg). Bufadienolides have been isolated recently from B. tubiflorum flowers and the syndrome is consistent with cardiac glycoside poisoning. PMID:3778371

McKenzie, R A; Dunster, P J

1986-07-01

439

Quality and Productivity Improvement of Wax Flowers  

Microsoft Academic Search

Waxflower (Chamelacium Uncinatum) originates in west Australia and includes more than 20 species. Waxflower is mainly used as bouquet filler. In Israel there is 200 hectare of Waxflower cultivars grown in open fields with an average annual yield of 350,000 flowers per hectare. The growing processes of Waxflowers are labor intensive, and the large numbers of workers involved in the

G. Vitner; A. Bechar; A. Kiryati; O. Eshet; O. Shental

440

Fertilisation of Winter-flowering Plants  

Microsoft Academic Search

MR. DARWIN has done me the honour of calling my attention to one or two points in my paper, published in your last number, ``On the Fertilisation of Winter-flowering Plants.'' He thinks there must be some error in my including Vinca major among the plants of which the pollen is discharged in the bud, as he ``knows from experiment that

Alfred W. Bknnett

1869-01-01

441

The Fertilisation of Winter-flowering Plants  

Microsoft Academic Search

WILL you permit me to add a few words to Mr. Bennett's letter, published at p. 58 of your last number? I did not cover up the Lamium with a bell-glass, but with what is called by ladies, ``net.'' During the last twenty years I have followed this plan, and have fertilised thousands of flowers thus covered up, but have

Charles Darwin

1869-01-01

442

The Genetic Architecture of Maize Flowering Time  

Technology Transfer Automated Retrieval System (TEKTRAN)

Flowering time is the key trait controlling adaptation of plants to their local environment, and, in an outcrossing species like maize, it is a complex trait. Variation for this complex trait was dissected in maize using a novel set of 5000 recombinant inbred lines (maize Nested Association Mapping...

443

Identification of Mendel's white flower character  

Technology Transfer Automated Retrieval System (TEKTRAN)

We have identified A, the factor determining anthocyanin pigmentation in pea that was used by Gregor Mendel 150 years ago in his study of inheritance. The A gene encodes a bHLH transcription factor. The white flowered mutant allele most likely used by Mendel is a simple G to A transition in a splice...

444

Geography in Parental Choice  

ERIC Educational Resources Information Center

If we are to fully understand the demand side of school choice, we have to understand geography. But geography is not simply distance and commute time. It is also neighborhood and community. Using two conceptions of geography--space and place--I investigate how and when geography factored into parents' thinking. Drawing on spatial analyses of…

Bell, Courtney

2009-01-01

445

Choices, Frameworks and Refinement  

NASA Technical Reports Server (NTRS)

In this paper we present a method for designing operating systems using object-oriented frameworks. A framework can be refined into subframeworks. Constraints specify the interactions between the subframeworks. We describe how we used object-oriented frameworks to design Choices, an object-oriented operating system.

Campbell, Roy H.; Islam, Nayeem; Johnson, Ralph; Kougiouris, Panos; Madany, Peter

1991-01-01

446

Choices, frameworks and refinement  

Microsoft Academic Search

Presents a method for designing operating systems using object-oriented frameworks. A framework can be refined into subframeworks. Constraints specify the interactions between the subframeworks. The authors describe how they used object-oriented frameworks to design Choices, an object-oriented operating system

Roy H. Campbell; Nayeem Islam; Ralph Johnson; Panos Kougiouris; Peter Madany

1991-01-01

447

Saying No to "Choice."  

ERIC Educational Resources Information Center

Name of Bush Administration's choice game is publicly financed vouchers allowing those already sending their children to private and parochial schools to avoid tuition fees at taxpayer expense. Although private schools administer entrance exams, public schools accept every child regardless of academic record, status, or race. U.S. Senate recently…

Penning, Nick

1992-01-01

448

Learning from School Choice.  

ERIC Educational Resources Information Center

This volume contains revised versions of 16 essays presented at a conference, "Rethinking School Governance," hosted by Harvard's Program on Education Policy and Governance in June 1997. Part 1, "Introduction," contains two chapters: (1) "School Choice: A Report Card" (Paul E. Peterson); and (2) "The Case for Charter Schools" (Bryan C. Hassel).…

Peterson, Paul E., Ed.; Hassel, Bryan C., Ed.

449

Green Lighting Choices  

NSDL National Science Digital Library

This brief article looks at sustainable choices in home and commercial lighting. The author discusses the energy use of several different types of bulbs, and their appropriate uses. The suggestions the author includes in the article are intended to be both environmentally responsible and have an appearance similar to other lighting projects. This document may be downloaded in Microsoft Word Doc file format.

Benya, James R.

450

Deterministic Walks with Choice  

SciTech Connect

This paper studies deterministic movement over toroidal grids, integrating local information, bounded memory and choice at individual nodes. The research is motivated by recent work on deterministic random walks, and applications in multi-agent systems. Several results regarding passing tokens through toroidal grids are discussed, as well as some open questions.

Beeler, Katy E.; Berenhaut, Kenneth S.; Cooper, Joshua N.; Hunter, Meagan N.; Barr, Peter S.

2014-01-10

451

Public Policy Report. Choices.  

ERIC Educational Resources Information Center

Describes the current post-Superwoman era in which women are more free to make choices about homemaking and employment. Women are now secure enough in the workforce that they can quit or work part-time without feeling they have let the sisterhood down. (CB)

Mann, Judy

1985-01-01

452

Choice of Living Arrangements  

ERIC Educational Resources Information Center

Background: The rights to choose where and with whom to live are widely endorsed but commonly denied to adults with intellectual disabilities (ID). The current study provides a contemporary benchmark on the degree of choice exercised by adult service users in the USA. Method: Data came from the National Core Indicators programme. Participants were…

Stancliffe, R. J.; Lakin, K. C.; Larson, S.; Engler, J.; Taub, S.; Fortune, J.

2011-01-01

453

Too Few Choices  

ERIC Educational Resources Information Center

In this article, the author, who is a scientist, a wife and a mother of two preschool children talks about how these two roles exerted a disproportionate impact on her career choices. She is also an X-Gal, one of a group of nine female biologists who have banded together to offer one another advice and support as they seek careers in academic…

Murray, Meg

2007-01-01

454

Multiple Choice Test  

NSDL National Science Digital Library

This site presents a guide to developing and deploying effective multiple choice tests. The site also discusses the costs and benefits of this method, as well as the philosophy of this commonly used assessment method. Links to more detailed information are included as well.

Jay Parkes

455

Colored floral organs influence pollinator behavior and pollen transfer in Commelina communis (Commelinaceae).  

PubMed

Visual floral guides such as colored anthers, lines, dots, and UV-absorption patterns on petals are commonly observed in insect-pollinated angiosperms. Floral guides that are known to enhance foraging efficiency of visitors on flowers thus promote return visits (foraging facilitation hypothesis, which predicts that visitors will discriminate against flowers with inferior floral guides). In this study, we experimentally examined the hypothesis that floral guides also prevent pollen-theft behavior by floral visitors (theft prevention hypothesis), which has rarely been tested. Nectarless flowers of Commelina communis have three types of brightly colored floral organs: large blue petals, rewarding yellow anthers, and nonrewarding yellow anthers. Colored floral organs were removed artificially from plants in two natural populations of C. communis. Removal of the nonrewarding yellow anthers diminished hoverings in front of flowers and tended to reduce the number of total floral visitor landings, supporting the foraging facilitation hypothesis. Additionally, removal of the rewarding yellow anther decreased the frequency of legitimate landings on flowers and the legitimate landing-to-total landing ratio, which is consistent with the theft prevention hypothesis. The nonrewarding anthers and the rewarding yellow anthers were shown to play an important role in increasing visitor landings and orienting floral visitors toward a landing point appropriate for pollination, respectively. We also showed that the absence of yellow anthers decreased both pollen dispatch from brown anthers and receipt by stigmas in C. communis. These findings support both the foraging facilitation hypothesis and the theft prevention hypothesis. PMID:21642227

Ushimaru, Atushi; Watanabe, Takeshi; Nakata, Kensuke

2007-02-01

456

Maturity and type of cutting influences flower yield, flowering time, and quality in Limonium ‘Chorus Magenta’  

Microsoft Academic Search

The influence of physiological maturity (3?, 6?, 9?, or 12?leaf axils) and type of cutting (whole cutting, top?half, or bottom?half) on the yield, time to flower, and flower and stem characteristics of Limonium ‘Chorus Magenta’ were assessed. Cuttings struck at an increased maturity (9? and 12?leaf axils) with apical meristems retained (whole and top?half types) had the potential to produce

K. A. Funnell; M. Bendall; W. F. Fountain; E. R. Morgan

2003-01-01

457

Foraging Ability of Rufous Hummingbirds on Hummingbird Flowers and Hawkmoth Flowers  

Microsoft Academic Search

We examine the suitability of ornithophilous flowers and sphingophilous flowers in Ipompsis and Aquilegia for nectar foraging by the hummingbird Selasphorus rufus. In S. rufus, bill length averages 18.9 mm in females and 17.3 mm in males. Maximal tongue extension approximates bill length, suggesting that birds can feed from floral tubes up to 33.5 mm in length. However, their ability

Verne Grant; Ethan J. Temeles

1992-01-01

458

Possible contributions of TERMINAL FLOWER 1 to the evolution of rosette flowering in Leavenworthia (Brassicaceae)  

PubMed Central

Summary Leavenworthia crassa is a rosette flowering species that differs from inflorescence flowering species, such as Arabidopsis thaliana, in having elongated pedicels and shortened interfloral internodes on the main axis. Based on previous experiments, we hypothesized that changes to the L. crassa TFL1 ortholog, LcrTFL1, were important in the evolution of rosette flowering.We isolated LcrTFL1 and introduced a genomic construct into tfl1 mutant A. thaliana plants. We also generated and analyzed EGFP-LcrTFL1 reporter-fusion lines, and LcrTFL1/LcrLFY doubly transgenic lines.The transgene rescued the mutant defects, but manifested gain-of-function phenotypes. However, LcrTFL1 lines differed from 35S:TFL1 lines in several regards. Defects in floral meristem identity establishment were observed, as was the production of flowers with extra petals. We also noted features that resemble rosette flowering: LcrTFL1 lines produced significantly shorter interfloral internodes and significantly longer pedicels than either wild-type or 35S:TFL1 plants.Our data show that there are substantive differences in the regulation and/or function of TFL1 orthologs between A. thaliana and L. crassa. These may reflect changes that occurred during the evolution of rosette flowering in Leavenworthia, but, if so, our results show that additional, as-yet-unidentified genes were involved in this instance of architectural evolution. PMID:21054410

Liu, Ning; Sliwinski, Marek K.; Correa, Raul; Baum, David A.

2011-01-01

459

Why are fruits colorful? The relative importance of achromatic and chromatic contrasts for detection by birds  

Microsoft Academic Search

The colors of fruits and flowers are traditionally viewed as an adaptation to increase the detectability of plant organs to\\u000a animal vectors. The detectability of visual signals increases with increasing contrasts between target and background. Contrasts\\u000a consist of a chromatic aspect (color) and an achromatic aspect (light intensity), which are perceived separately by animals.\\u000a To evaluate the relative importance of

Eliana Cazetta; Hinrich Martin Schaefer; Mauro Galetti

2009-01-01

460

SYNTHESIS Meta-analysis of phenotypic selection on flowering phenology suggests that early flowering plants are favoured  

E-print Network

REVIEW AND SYNTHESIS Meta-analysis of phenotypic selection on flowering phenology suggests that early flowering plants are favoured Miguel A. Mungui´a-Rosas,1,2 * Jeff Ollerton,2 Victor Parra-Tabla1 and J. Arturo De-Nova3 Abstract Flowering times of plants are important life-history components

Northampton, University of

461

Hypnotic self administration: forced-choice versus single-choice  

Microsoft Academic Search

Twenty-four men and women with insomnia, age 21–50?years, self administered hypnotics under a single-choice with placebo,\\u000a single-choice with triazolam (0.25?mg), or forced-choice of placebo versus triazolam (0.25?mg) paradigm. Subjects received\\u000a 4-sampling nights of placebo or triazolam in the single-choice conditions or 2 nights of each in the forced-choice condition.\\u000a Then on 7 choice nights they could self administer a capsule,

T. Roehrs; Bonita Pedrosi; Leon Rosenthal; Frank Zorick; Thomas Roth

1997-01-01

462

Color in architecture  

E-print Network

Good design can be spoiled by poor color. Weak design can be helped by good color. Color is therefore of prime importance as an integral element of architectural design. Color is vitally related to man in many fields. The study of architecture...

Vrooman, Richard

1952-01-01

463

Color identification testing device  

NASA Technical Reports Server (NTRS)

Testing device, which determines ability of a technician to identify color-coded electric wires, is superior to standard color blindness tests. It tests speed of wire selection, detects partial color blindness, allows rapid testing, and may be administered by a color blind person.

Brawner, E. L.; Martin, R.; Pate, W.

1970-01-01

464

Urine - abnormal color  

MedlinePLUS

The usual color of urine is straw-yellow. Abnormally colored urine may be cloudy, dark, or blood-colored. ... Abnormal urine color may be caused by infection, disease, medicines, or food you eat. Cloudy or milky urine is a sign ...

465

Color quantization of images  

Microsoft Academic Search

The authors develop algorithms for the design of hierarchical tree structured color palettes incorporating performance criteria which reflect subjective evaluations of image quality. Tree structured color palettes greatly reduce the computational requirements of the palette design and pixel mapping tasks, while allowing colors to be properly allocated to densely populated areas of the color space. The algorithms produce higher-quality displayed

Michael T. Orchard; Charles A. Bouman

1991-01-01

466

Color Transfer between Images  

Microsoft Academic Search

Often this means removing a dominant and undesirable color cast, such as the yellow in photos taken under incandescent illumination. This article describes a method for a more general form of color correction that borrows one image's color characteristics from anoth-er. Figure 1 shows an example of this process, where we applied the colors of a sunset photograph to a

Erik Reinhard; Michael Ashikhmin; Bruce Gooch; Peter Shirley

2001-01-01

467

Distance Coloring Alexa Sharp  

E-print Network

words: graph coloring, power graphs, complexity threshold 1 Introduction The classic k-coloring problem. Conversely, (d, k)-coloring a graph G is equivalent to k-coloring Gd , the dth power graph of G. (The graph of practical use in applications with underlying structures that fit the power graph model. For example, we may

Sharp, Alexa

468

Color: An Unsuspected Influence.  

ERIC Educational Resources Information Center

Discusses the appropriate use of colors in school libraries. Highlights include how colors affect students' learning and behavior; influences on users' moods; users' ages; the use of colors to bring out the best physical attributes; and the use of color for floor coverings, window treatments, furnishings, and accessories. (LRW)

Scargall, Hollie

1999-01-01

469

RGB Additive Color  

NSDL National Science Digital Library

Color is all around us. RGB is the color system that is used when mixing light. The RGB system is what we use in computers, televisions, stage lighting, displays and more. It is also called the additive color system because the colors are combined or added to each other to make the colors that we see. What wavelength goes with a color? Remember that a a nanometer is a unit of length in the metric system equal to one billionth of a meter. NASA What is a wave? NASA Color Why is the sky blue? What is RGB and how and where is it used? RGB World 21st Century Color Theory RGB colors are identified on computers by a color value that ranges for R, G, and B, ...

Mr. Engelman

2010-12-05

470

A possible role of an anthocyanin filter in low-intensity light stress-induced flowering in Perilla frutescens var. crispa.  

PubMed

The red-leaved form of Perilla frutescens var. crispa was induced to flower by low-intensity light stress. The leaves of this form are normally red, but turned green under low-intensity light due to anthocyanin depletion in the epidermis. Flowering did not occur when plants were grown under light passed through a red-colored cellophane paper, which has an absorption spectrum similar to that of anthocyanins. High-concentration anthocyanins may play the role of a red-colored optical filter under normal light conditions, and this filter effect may be lost under low-intensity light, causing a change in the wavelength characteristics of the light with which the mesophyll cells are irradiated. This change may induce a photobiological effect leading to flowering. The gene expression and enzyme activity of phenylalanine ammonia-lyase (PAL), the key enzyme for anthocyanin biosynthesis, decreased under low-intensity light. L-2-aminooxy-3-phenylpropionic acid (AOPP), which is widely used as a PAL inhibitor, inhibited low-intensity light stress-induced flowering and increased PAL activity and anthocyanin content. The inhibition of flowering by AOPP in P. frutescens may be through different mechanisms than PAL inhibition. PMID:25544591

Miki, Satomi; Wada, Kaede C; Takeno, Kiyotoshi

2015-03-01

471

Models for forecasting the flowering of Cornicabra olive groves  

NASA Astrophysics Data System (ADS)

This study examined the impact of weather-related variables on flowering phenology in the Cornicabra olive tree and constructed models based on linear and Poisson regression to forecast the onset and length of the pre-flowering and flowering phenophases. Spain is the world's leading olive oil producer, and the Cornicabra variety is the second largest Spanish variety in terms of surface area. However, there has been little phenological research into this variety. Phenological observations were made over a 5-year period (2009-2013) at four sampling sites in the province of Toledo (central Spain). Results showed that the onset of the pre-flowering phase is governed largely by temperature, which displayed a positive correlation with the temperature in the start of dormancy (November) and a negative correlation during the months prior to budburst (January, February and March). A similar relationship was recorded for the onset of flowering. Other weather-related variables, including solar radiation and rainfall, also influenced the succession of olive flowering phenophases. Linear models proved the most suitable for forecasting the onset and length of the pre-flowering period and the onset of flowering. The onset and length of pre-flowering can be predicted up to 1 or 2 months prior to budburst, whilst the onset of flowering can be forecast up to 3 months beforehand. By contrast, a nonlinear model using Poisson regression was best suited to predict the length of the flowering period.

Rojo, Jesús; Pérez-Badia, Rosa

2015-02-01

472

Role of Cytokinins in Carnation Flower Senescence 1  

PubMed Central

Stem and leaf tissues of carnation (Dianthus caryophyllus) plants appear to contain a natural antisenescence factor since removal of most of these tissues from cut carnation flowers hastened their senescence. However, kinetin (5-10 ?g/ml) significantly delayed senescence of flowers with stem and leaf tissues removed. In addition, the life span of cut flowers with intact (30-cm) stems was increased with kinetin treatment. Peak ethylene production by presenescent flowers was reduced 55% or more with kinetin treatment and was delayed by 1 day. Kinetin-treated flowers were less responsive to applied ethylene (100 ?l/l for 3 hours) than untreated flowers. Possible natural roles of cytokinins in carnation flower senescence are discussed. PMID:16659922

Eisinger, William

1977-01-01

473

Photosynthate partitioning during flowering in relation to senescence of spinach  

SciTech Connect

Male spinach plants are frequently cited as a counter-example to the nutrient drain hypothesis. Photosynthate partitioning in both male and female plants was examined. Leaves just below the inflorescences in plants at various stages of flowering were labelled with {sup 14}CO{sub 2} and the photosynthate allowed to partition for three hours. The leaves, flowers and stems of the inflorescence, and the other above ground vegetative tissue were harvested. These parts were combusted in a sample oxidizer for the collection of the {sup 14}CO{sub 2}. Allocation to the male and female flowers at very early stages are similar. As the flowers develop further, male flowers receive more photosynthate than do female flowers in early fruit production. Thus it is possible that nutrient drain to the flowers in male spinach plants is sufficient to account for senescence.

Sklensky, D.; Davies, P.J. (Cornell Univ., Ithaca, NY (USA))

1990-05-01

474

Direct and indirect selection on floral pigmentation by pollinators and seed predators in a color polymorphic South African shrub.  

PubMed

The coexistence of different color morphs is often attributed to variable selection pressures across space, time, morph frequencies, or selection agents, but the routes by which each morph is favored are rarely identified. In this study we investigated factors that influence floral color polymorphisms on a local scale in Protea, within which approximately 40% of species are polymorphic. Previous work shows that seed predators and reproductive differences likely contribute to maintaining polymorphism in four Protea species. We explored whether selection acts directly or indirectly on floral color in two populations of Protea aurea, using path analysis of pollinator behavior, nectar production, seed predation, color, morphology, and maternal fecundity fitness components. We found that avian pollinators spent more time on white morphs, likely due to nectar differences, but that this had no apparent consequences for fecundity. Instead, the number of flowers per inflorescence underpinned many of the reproductively important differences between color morphs. White morphs had more flowers per inflorescence, which itself was positively correlated with nectar production, seed predator occurrence, and total long-term seed production. The number of seeds per plant to survive predation, in contrast, was not directly associated with color or any other floral trait. Thus, although color differences may be associated with conflicting selection pressures, the selection appears to be associated with the number of flowers per inflorescence and its unmeasured correlates, rather than with inflorescence color itself. PMID:23007806

Carlson, Jane E; Holsinger, Kent E

2013-04-01

475

CropChoice  

NSDL National Science Digital Library

CropChoice is an alternative news and information source for American farmers and consumers about genetically modified crops, corporate agribusiness concentration, farm and trade policy, sustainable agriculture, wind farming and alternative energy, and rural economic and social issues. Users can explore the site's resources by topic, search past headlines and view press releases. Links are provided to sites that involve similar issues and information.

2007-04-16

476

Origin choice and petal loss in the flower garden of spiral wave tip trajectories  

PubMed Central

Rotating spiral waves have been observed in numerous biological and physical systems. These spiral waves can be stationary, meander, or even degenerate into multiple unstable rotating waves. The spatiotemporal behavior of spiral waves has been extensively quantified by tracking spiral wave tip trajectories. However, the precise methodology of identifying the spiral wave tip and its influence on the specific patterns of behavior remains a largely unexplored topic of research. Here we use a two-state variable FitzHugh–Nagumo model to simulate stationary and meandering spiral waves and examine the spatiotemporal representation of the system’s state variables in both the real (i.e., physical) and state spaces. We show that mapping between these two spaces provides a method to demarcate the spiral wave tip as the center of rotation of the solution to the underlying nonlinear partial differential equations. This approach leads to the simplest tip trajectories by eliminating portions resulting from the rotational component of the spiral wave. PMID:19791998

Gray, Richard A.; Wikswo, John P.; Otani, Niels F.

2009-01-01

477

Choice Flowers and Well-Ordered Tables: Struggling Over Gender in a Nineteenth-Century Household  

Microsoft Academic Search

Historical archaeologists have generally considered households as isolated,bounded entities, and not as sets of social relations. Consequently, the household has gone unrecognized as an arena of struggle. Analysis of documents associated with the household of nineteenth-century reformer Gerrit Smith challenges this approach. At his Peterboro, New York estate, a struggle ensued between family members because of conflicting ideologies of self-presentation,

Hadley Kruczek-Aaron

2002-01-01

478

Recursive rational choice  

SciTech Connect

It is the purpose of the present study to indicate the means by which Kramer's results may be generalized to considerations of stronger computing devices than the finite state automata considered in Kramer's approach, and to domains of alternatives having the cardinality of the continuum. The means we employ in the approach makes use of the theory of recursive functions in the context of Church's Thesis. The result, which we consider as a preliminary result to a more general research program, shows that a choice function that is rational in the sense of Richter (not necessarily regular) when defined on a restricted family of subsets of a continuum of alternatives, when recursively represented by a partial predicate on equivalence classes of approximations by rational numbers, is recursively unsolvable. By way of Church's Thesis, therefore, such a function cannot be realized by means of a very general class of effectively computable procedures. An additional consequence that can be derived from the result of recursive unsolvability of rational choice in this setting is the placement of a minimal bound on the amount of computational complexity entailed by effective realizations of rational choice.

Lewis, A.A.

1981-11-01

479

Mass flowering of the tropical tree Shorea beccariana was preceded by expression changes in flowering and drought-responsive genes  

PubMed Central

Community-level mass flowering, known as general flowering, which occurs in South-East Asia at supra-annual irregular intervals, is considered a particularly spectacular phenomenon in tropical ecology. Recent studies have proposed several proximate factors inducing general flowering, such as drought and falls in minimum temperature. However, limited empirical data on the developmental and physiological processes have been available to test the significance of such factors. To overcome this limitation and test the hypotheses that general flowering is triggered by the proposed factors, we conducted an ‘ecological transcriptome’ study of a mass flowering species, Shorea beccariana, comparing meteorological data with genome-wide expression patterns obtained using next-generation sequencing. Among the 98 flowering-related genes identified, the homologs of a floral pathway integrator, SbFT, and a floral repressor, SbSVP, showed dramatic transcriptional changes before flowering, and their flowering functions were confirmed using transgenic Arabidopsis thaliana. Expression in drought-responsive and sucrose-induced genes also changed before flowering. All these expression changes occurred when the flowering-inducing level of drought was reached, as estimated using data from the preceding 10 years. These genome-wide expression data support the hypothesis that drought is a trigger for general flowering. PMID:23651119

Kobayashi, Masaki J; Takeuchi, Yayoi; Kenta, Tanaka; Kume, Tomonori; Diway, Bibian; Shimizu, Kentaro K

2013-01-01

480

Fruits and Vegetables: Color Your Plate  

NSDL National Science Digital Library

In this activity, learners explore healthy choices related to the foods they eat. The importance of a variety of fruits and vegetables to a healthy diet is the focus of the experience. Learners read a story book about fruits and vegetables, repeat a helpful riddle, and draw pictures of fruits/vegetables. These drawings are then cut out and taped to "color" a Healthy Choice bulletin board plate. Learners can also taste-test different fruits and vegetables at snack or lunch time. Learners are encouraged to try one new color each day. This activity is featured on pp. 12-13 of the "Health House: Food, Fitness, & Fun 24/7!" unit of study for K-2 learners.

Dr. Beverly A. Reitsma

2014-04-30

481

Epigenetic regulation of rice flowering and reproduction  

PubMed Central

Current understanding of the epigenetic regulator roles in plant growth and development has largely derived from studies in the dicotyledonous model plant Arabidopsis thaliana. Rice (Oryza sativa) is one of the most important food crops in the world and has more recently becoming a monocotyledonous model plant in functional genomics research. During the past few years, an increasing number of studies have reported the impact of DNA methylation, non-coding RNAs and histone modifications on transcription regulation, flowering time control, and reproduction in rice. Here, we review these studies to provide an updated complete view about chromatin modifiers characterized in rice and in particular on their roles in epigenetic regulation of flowering time, reproduction, and seed development. PMID:25674094

Shi, Jinlei; Dong, Aiwu; Shen, Wen-Hui

2015-01-01

482

Sustainable Stanford Greening Infrastructure & Choices  

E-print Network

Sustainable Stanford Greening Infrastructure & Choices Fahmida Ahmed Office of Sustainability #12Economy Institutional & Individual Choices Sustainability at Stanford #12;The Stanford Ecosystem Infrastructure, Education and Outreach Infrastructure Planning Support Evaluations & Reporting Communication & Publication

483

Mountain Health Choices Beneficiary Report  

E-print Network

Mountain Health Choices Beneficiary Report A Report to the West Virginia Bureau for Medical of Health and Human Resources, Bureau for Medical Services. #12; 1 Table of Contents I. EXECUTIVE .......................................................................................................................... 5 II. MOUNTAIN HEALTH CHOICES

Mohaghegh, Shahab

484

How genes paint flowers and seeds  

Microsoft Academic Search

Mutant analyses have given insight into the various parameters that contribute to flower colour and pattern, which is so important for pollination. One important factor is the accumulation of orange, red and purple anthocyanin pigments in the cell vacuole—patterns arise by cell-specific expression of combinations of regulatory proteins. The overall colour perceived is also influenced by vacuolar pH, co-pigmentation and

Joseph Mol; Erich Grotewold; Ronald Koes

1998-01-01

485

Genes Directing Flower Development in Arabidopsis  

Microsoft Academic Search

We describe the effects of four recessive homeotic mutations that specifically disrupt the development of flowers in Arabidopsis thaliana. Each of the recessive mutations affects the outcome of organ development, but not the location of organ primordia. Homeotic transformations observed are as follows. In agamous-1, stamens to petals; in apetala2-1, sepals to leaves and petals to staminoid petals; in apefala3-1,

John L. Bowman; David R. Smyth; Elliot M. Meyerowitz

1989-01-01

486

Constituents of the flowers of Punica granatum.  

PubMed

A new polyphenol compound named pomegranatate (1), together with, ellagic acid, 3,3',4'-tri-O-methylellagic acid, ethyl brevifolincarboxylate, urolic and maslinic acids, and daucosterol were isolated from the ethanolic extract of the flowers of Punica granatum. The structure of compound 1 was determined by spectroscopic analysis. Maslinic acid exhibited antioxidant activity, evaluated by measurement of LDL susceptibility to oxidation. PMID:16887296

Wang, Rufeng; Wei Wang; Wang, Liang; Liu, Ruining; Yi Ding; Du, Lijun

2006-12-01

487

Fibonacci, quasicrystals and the beauty of flowers  

PubMed Central

The appearance of Fibonacci sequences and the golden ratio in plant structures is one of the great outstanding puzzles of biology. Here I suggest that quasicrystals, which naturally pack in the golden ratio, may be ubiquitous in biological systems and introduce the golden ratio into plant phyllotaxy. The appearance of golden ratio-based structures as beautiful indicates that the golden ratio may play a role in the development of consciousness and lead to the aesthetic natural selection of flowering plants. PMID:23072998

Gardiner, John

2012-01-01

488

Bamboo-Dominated Forests of the Southwest Amazon: Detection, Spatial Extent, Life Cycle Length and Flowering Waves  

PubMed Central

We map the extent, infer the life-cycle length and describe spatial and temporal patterns of flowering of sarmentose bamboos (Guadua spp) in upland forests of the southwest Amazon. We first examine the spectra and the spectral separation of forests with different bamboo life stages. False-color composites from orbital sensors going back to 1975 are capable of distinguishing life stages. These woody bamboos flower produce massive quantities of seeds and then die. Life stage is synchronized, forming a single cohort within each population. Bamboo dominates at least 161,500 km2 of forest, coincident with an area of recent or ongoing tectonic uplift, rapid mechanical erosion and poorly drained soils rich in exchangeable cations. Each bamboo population is confined to a single spatially continuous patch or to a core patch with small outliers. Using spatial congruence between pairs of mature-stage maps from different years, we estimate an average life cycle of 27–28 y. It is now possible to predict exactly where and approximately when new bamboo mortality events will occur. We also map 74 bamboo populations that flowered between 2001 and 2008 over the entire domain of bamboo-dominated forest. Population size averaged 330 km2. Flowering events of these populations are temporally and/or spatially separated, restricting or preventing gene exchange. Nonetheless, adjacent populations flower closer in time than expected by chance, forming flowering waves. This may be a consequence of allochronic divergence from fewer ancestral populations and suggests a long history of widespread bamboo in the southwest Amazon. PMID:23359438

de Carvalho, Anelena L.; Nelson, Bruce W.; Bianchini, Milton C.; Plagnol, Daniela; Kuplich, Tatiana M.; Daly, Douglas C.

2013-01-01