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Sample records for flowering hormone florigen

  1. The flowering hormone florigen functions as a general systemic regulator of growth and termination

    OpenAIRE

    Shalit, Akiva; Rozman, Alexander; Goldshmidt, Alexander; Alvarez, John P.; Bowman, John L.; Eshed, Yuval; Lifschitz, Eliezer

    2009-01-01

    The florigen paradigm implies a universal flowering-inducing hormone that is common to all flowering plants. Recent work identified FT orthologues as originators of florigen and their polypeptides as the likely systemic agent. However, the developmental processes targeted by florigen remained unknown. Here we identify local balances between SINGLE FLOWER TRUSS (SFT), the tomato precursor of florigen, and SELF-PRUNING (SP), a potent SFT-dependent SFT inhibitor as prime targets of mobile florig...

  2. The flowering hormone florigen functions as a general systemic regulator of growth and termination.

    Science.gov (United States)

    Shalit, Akiva; Rozman, Alexander; Goldshmidt, Alexander; Alvarez, John P; Bowman, John L; Eshed, Yuval; Lifschitz, Eliezer

    2009-05-19

    The florigen paradigm implies a universal flowering-inducing hormone that is common to all flowering plants. Recent work identified FT orthologues as originators of florigen and their polypeptides as the likely systemic agent. However, the developmental processes targeted by florigen remained unknown. Here we identify local balances between SINGLE FLOWER TRUSS (SFT), the tomato precursor of florigen, and SELF-PRUNING (SP), a potent SFT-dependent SFT inhibitor as prime targets of mobile florigen. The graft-transmissible impacts of florigen on organ-specific traits in perennial tomato show that in addition to import by shoot apical meristems, florigen is imported by organs in which SFT is already expressed. By modulating local SFT/SP balances, florigen confers differential flowering responses of primary and secondary apical meristems, regulates the reiterative growth and termination cycles typical of perennial plants, accelerates leaf maturation, and influences the complexity of compound leaves, the growth of stems and the formation of abscission zones. Florigen is thus established as a plant protein functioning as a general growth hormone. Developmental interactions and a phylogenetic analysis suggest that the SFT/SP regulatory hierarchy is a recent evolutionary innovation unique to flowering plants.

  3. Beyond flowering time: pleiotropic function of the maize flowering hormone florigen.

    Science.gov (United States)

    Danilevskaya, Olga N; Meng, Xin; McGonigle, Brian; Muszynski, Michael G

    2011-09-01

    The transition from vegetative to reproductive development is a critical turning point in a plant’s life cycle. It is now widely accepted that a leaf-borne signal, florigen, moves via the phloem from leaves to the shoot apical meristem to trigger its reprogramming to produce flowers. In part, the florigenic signal comprises a protein that belongs to the phosphatidylethanolamine-binding protein (PEBP) family that is present in all living organisms but displays diverse functions. The founding floral-promoting PEBP gene in Arabidopsis is FLOWERING LOCUS T (FT) whose functional homologs have been indentified in many flowering plants. We recently accumulated sufficient evidence to demonstrate the maize FT homolog ZCN8 has florigenic function. This task was particularly challenging due to the large number of FT-homologous genes in the maize genome. Here we show that ZCN8 function is more complex than simply regulating the floral transition. ZCN8 appears to play a pleiotropic role in the regulation of generalized growth of vegetative and reproductive tissues.

  4. Flowering time: from photoperiodism to florigen.

    Science.gov (United States)

    Ma, H

    1998-09-24

    An Arabidopsis blue-light receptor, Cry2, has been found to play a critical role in the photoperiodic control of flowering time; and genes have been identified that may control the production of a transmissible flower-inducing signal, which may turn out to be the long-elusive putative flowering hormone 'florigen'.

  5. Florigen and anti-florigen - a systemic mechanism for coordinating growth and termination in flowering plants.

    Science.gov (United States)

    Lifschitz, Eliezer; Ayre, Brian G; Eshed, Yuval

    2014-01-01

    Genetic studies in Arabidopsis established FLOWERING LOCUS T (FT) as a key flower-promoting gene in photoperiodic systems. Grafting experiments established unequivocal one-to-one relations between SINGLE FLOWER TRUSS (SFT), a tomato homolog of FT, and the hypothetical florigen, in all flowering plants. Additional studies of SFT and SELF PRUNING (SP, homolog of TFL1), two antagonistic genes regulating the architecture of the sympodial shoot system, have suggested that transition to flowering in the day-neutral and perennial tomato is synonymous with "termination." Dosage manipulation of its endogenous and mobile, graft-transmissible levels demonstrated that florigen regulates termination and transition to flowering in an SP-dependent manner and, by the same token, that high florigen levels induce growth arrest and termination in meristems across the tomato shoot system. It was thus proposed that growth balances, and consequently the patterning of the shoot systems in all plants, are mediated by endogenous, meristem-specific dynamic SFT/SP ratios and that shifts to termination by changing SFT/SP ratios are triggered by the imported florigen, the mobile form of SFT. Florigen is a universal plant growth hormone inherently checked by a complementary antagonistic systemic system. Thus, an examination of the endogenous functions of FT-like genes, or of the systemic roles of the mobile florigen in any plant species, that fails to pay careful attention to the balancing antagonistic systems, or to consider its functions in day-neutral or perennial plants, would be incomplete.

  6. Florigen and anti-florigen - a systemic mechanism for coordinating growth and termination in flowering plants

    Directory of Open Access Journals (Sweden)

    Eliezer eLifschitz

    2014-09-01

    Full Text Available Genetic studies in Arabidopsis established FLOWERING LOCUS T (FT as a key flower-promoting gene in photoperiodic systems. Grafting experiments established unequivocal one-to-one relations between SFT (SINGLE FLOWER TRUSS, a tomato homolog of FT, and the hypothetical florigen, in all flowering plants. Additional studies of SFT and SP (SELF PRUNING, homolog of TFL1, two antagonistic genes regulating the architecture of the sympodial shoot system, have suggested that transition to flowering in the day-neutral and perennial tomato is synonymous with ‘termination’. Dosage manipulation of its endogenous and mobile, graft-transmissible levels demonstrated that florigen regulates termination and transition to flowering in an SP-dependent manner and, by the same token, that high florigen levels induce growth arrest and termination in meristems across the tomato shoot system. It was thus proposed that growth balances, and consequently the patterning of the shoot systems in all plants, are mediated by endogenous, meristem-specific SFT/SP ratios, and that shifts to termination by elevated SFT/SP ratios are triggered by mobile florigen. Florigen is a universal growth plant hormone inherently checked by a complementary antagonistic systemic system. Thus, an examination of the endogenous functions of FT-like genes, or of the systemic roles of the mobile florigen in any plant species, that fails to pay careful attention to the balancing antagonistic systems, or to consider its functions in day-neutral or perennial plants, would be incomplete.

  7. Florigen and anti-florigen - a systemic mechanism for coordinating growth and termination in flowering plants

    OpenAIRE

    Eliezer eLifschitz; Brian G. Ayre; Yuval eEshed

    2014-01-01

    Genetic studies in Arabidopsis established FLOWERING LOCUS T (FT) as a key flower-promoting gene in photoperiodic systems. Grafting experiments established unequivocal one-to-one relations between SFT (SINGLE FLOWER TRUSS), a tomato homolog of FT, and the hypothetical florigen, in all flowering plants. Additional studies of SFT and SP (SELF PRUNING, homolog of TFL1), two antagonistic genes regulating the architecture of the sympodial shoot system, have suggested that transition to flowering i...

  8. FT and florigen long-distance flowering control in plants.

    Science.gov (United States)

    Putterill, Joanna; Varkonyi-Gasic, Erika

    2016-10-01

    The great hunt for florigen, the universal, long distance flowering regulator proposed by Chailakhan in the 1930s, resulted in the discovery a decade ago that FT-like proteins fulfilled the predictions for florigen. They are small (∼175 amino acids), globular, phosphatidylethanolamine-binding (PEBP) proteins, phloem-expressed, graft-transmissible and able to move to the shoot apex to act as potent stimulators of flowering in many plants. Genes that regulate Arabidopsis FT protein movement and some features of Arabidopsis FT protein that make it an effective florigen have recently been identified. Although floral promotion via graft transmission of FT has not been demonstrated in trees, FT-like genes have been successfully applied to reducing the long juvenile (pre-flowering) phase of many trees enabling fast track breeding.

  9. Florigen and anti-florigen – a systemic mechanism for coordinating growth and termination in flowering plants

    OpenAIRE

    Lifschitz, Eliezer; Brian G. Ayre; Eshed, Yuval

    2014-01-01

    Genetic studies in Arabidopsis established FLOWERING LOCUS T (FT) as a key flower-promoting gene in photoperiodic systems. Grafting experiments established unequivocal one-to-one relations between SINGLE FLOWER TRUSS (SFT), a tomato homolog of FT, and the hypothetical florigen, in all flowering plants. Additional studies of SFT and SELF PRUNING (SP, homolog of TFL1), two antagonistic genes regulating the architecture of the sympodial shoot system, have suggested that transition to flowering i...

  10. Gibberellins and flowering of grasses and cereals: prizing open the lid of the "florigen" black box.

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    King, Rod W; Evans, Lloyd T

    2003-01-01

    Comprehensive studies in grasses show that gibberellins (GAs) play a role as a florigen. For Lolium temulentum, which flowers in response to a single long day (LD), GAs are a transmitted signal, their content increasing in the leaf early in the LD and then, hours later, at the shoot apex. There is a continuous trail of evidence of hormonal action of these GAs for L. temulentum and support for a similar role in the flowering of other LD-responsive temperate grasses and cereals. A characteristic of the initial flowering responses of grasses and cereals is their limited stem elongation. Interestingly, it is GAs with low effectiveness for stem elongation, GA5 and GA6, that reach the shoot apex and, structurally, are probably not degraded by 2-oxidase enzymes. By contrast, GA1 and GA4 cause stem elongation, may be inactive for floral evocation, and do not reach the vegetative shoot apex apparently because of susceptibility to degradation. However, GA4 can be florally active if protected against 2-oxidases either structurally or by using a 2-oxidase inhibitor. Later in inflorescence development, GA1 and GA4 can be detected at the shoot apex and are florally active if applied. The 2-oxidase restricting accessibility to the apex has probably declined at this time so there is a second florigenic, LD-regulated GA action. A growing body of molecular evidence supporting these actions of GA may provide a future basis for manipulating flowering of grasses and cereals.

  11. Regulation and identity of florigen: FLOWERING LOCUS T moves center stage.

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    Turck, Franziska; Fornara, Fabio; Coupland, George

    2008-01-01

    The transition from vegetative to reproductive growth is controlled by day length in many plant species. Day length is perceived in leaves and induces a systemic signal, called florigen, that moves through the phloem to the shoot apex. At the shoot apical meristem (SAM), florigen causes changes in gene expression that reprogram the SAM to form flowers instead of leaves. Analysis of flowering of Arabidopsis thaliana placed the CONSTANS/FLOWERING LOCUS T (CO/FT) module at the core of a pathway that promotes flowering in response to changes in day length. We describe progress in defining the molecular mechanisms that activate this module in response to changing day length and the increasing evidence that FT protein is a major component of florigen. Finally, we discuss conservation of FT function in other species and how variation in its regulation could generate different flowering behaviors.

  12. Regulation of flowering in rice: two florigen genes, a complex gene network, and natural variation.

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    Tsuji, Hiroyuki; Taoka, Ken-ichiro; Shimamoto, Ko

    2011-02-01

    Photoperiodic control of flowering time consists of a complicated network that converges into the generation of a mobile flowering signal called florigen. Recent advances identifying the protein FT/Hd3a as the molecular nature responsible for florigen activity have focused current research on florigen genes as the important output of this complex signaling network. Rice is a model system for short-day plants and recent progress in elucidating the flowering network from rice and Arabidopsis, a long-day plant, provides an evolutionarily comparative view of the photoperiodic flowering pathway. This review summarizes photoperiodic flowering control in rice, including the interaction of complex layers of gene networks contributed from evolutionarily unique factors and the regulatory adaptation of conserved factors.

  13. Arabidopsis florigen FT binds to diurnally oscillating phospholipids that accelerate flowering.

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    Nakamura, Yuki; Andrés, Fernando; Kanehara, Kazue; Liu, Yu-chi; Dörmann, Peter; Coupland, George

    2014-04-04

    Arabidopsis FT protein is a component of florigen, which transmits photoperiodic flowering signals from leaf companion cells to the shoot apex. Here, we show that FT specifically binds phosphatidylcholine (PC) in vitro. A transgenic approach to increase PC levels in vivo in the shoot meristem accelerates flowering whereas reduced PC levels delay flowering, demonstrating that PC levels are correlated with flowering time. The early flowering is related to FT activity, because expression of FT-effector genes is increased in these plants. Simultaneous increase of FT and PC in the shoot apical meristem further stimulates flowering, whereas a loss of FT function leads to an attenuation of the effect of increased PC. Specific molecular species of PC oscillate diurnally, and night-dominant species are not the preferred ligands of FT. Elevating night-dominant species during the day delays flowering. We suggest that FT binds to diurnally changing molecular species of PC to promote flowering.

  14. "Florigen ": an intriguing concept of plant biology.

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    Pennazio, Sergio

    2004-01-01

    "Florigen" is the name that Mikhail Chailakhyan coined in 1937 for the putative hormone regulating flowering. At this concept, plant physiologists arrived following early research concerning the effects of temperature and day length on the transition from vegetative to reproductive stages of plants. The existence of florigen was postulated on the experimental backgrounds involving i) the response of plants to inductive conditions; ii) transmission of a flowering stimulus by grafting; iii) extraction of this stimulus from induced plants. This experimental results showed the existence of florigen at least as concept because they always failed to offer the experimental evidence of its chemical existence. The myth of florigen persisted as long as the end of the Seventies, when physiologists began to consider flowering as a complex process in which various classes of hormones might variously interplay.

  15. FLOWERING LOCUS T protein may act as the long-distance florigenic signal in the cucurbits.

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    Lin, Ming-Kuem; Belanger, Helene; Lee, Young-Jin; Varkonyi-Gasic, Erika; Taoka, Ken-Ichiro; Miura, Eriko; Xoconostle-Cázares, Beatriz; Gendler, Karla; Jorgensen, Richard A; Phinney, Brett; Lough, Tony J; Lucas, William J

    2007-05-01

    Cucurbita moschata, a cucurbit species responsive to inductive short-day (SD) photoperiods, and Zucchini yellow mosaic virus (ZYMV) were used to test whether long-distance movement of FLOWERING LOCUS T (FT) mRNA or FT is required for floral induction. Ectopic expression of FT by ZYMV was highly effective in mediating floral induction of long-day (LD)-treated plants. Moreover, the infection zone of ZYMV was far removed from floral meristems, suggesting that FT transcripts do not function as the florigenic signal in this system. Heterografting demonstrated efficient transmission of a florigenic signal from flowering Cucurbita maxima stocks to LD-grown C. moschata scions. Real-time RT-PCR performed on phloem sap collected from C. maxima stocks detected no FT transcripts, whereas mass spectrometry of phloem sap proteins revealed the presence of Cm-FTL1 and Cm-FTL2. Importantly, studies on LD- and SD-treated C. moschata plants established that Cmo-FTL1 and Cmo-FTL2 are regulated by photoperiod at the level of movement into the phloem and not by transcription. Finally, mass spectrometry of florally induced heterografted C. moschata scions revealed that C. maxima FT, but not FT mRNA, crossed the graft union in the phloem translocation stream. Collectively, these studies are consistent with FT functioning as a component of the florigenic signaling system in the cucurbits.

  16. Enabling photoperiodic control of flowering by timely chromatin silencing of the florigen gene.

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    He, Yuehui

    2015-01-01

    Many plants synchronize their flowering times with changing seasons to maximize reproductive success. A key seasonal cue is the change in day length (photoperiod), that induces the production of a systemic flowering signaling molecule called florigen. A major florigen component is FLOWERING LOCUS T (FT) or its orthologs. In the long-day plant Arabidopsis thaliana, FT expression is well known to be activated by the photoperiod pathway output specifically near dusk in long days; however, underappreciated is the importance of FT silencing at other times of the day, in enabling Arabidopsis to respond only to long days in flowering. We have recently reported that a plant-specific chromatin-silencing complex called EMF1c represses FT expression at times other than around dusk in long days to prevent its temporal ectopic expression from "spoiling" the long-day floral induction in Arabidopsis. Here I further discuss in other day-length sensitive plants the potential involvement of a chromatin mechanism similar to the Arabidopsis EMF1c-mediated silencing, in repressing the expression of FT orthologs to enable diverse photoperiodic control of flowering.

  17. ZCN8 encodes a potential orthologue of Arabidopsis FT florigen that integrates both endogenous and photoperiod flowering signals in maize.

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    Lazakis, Chloë M; Coneva, Viktoriya; Colasanti, Joseph

    2011-10-01

    Higher plants use multiple perceptive measures to coordinate flowering time with environmental and endogenous cues. Physiological studies show that florigen is a mobile factor that transmits floral inductive signals from the leaf to the shoot apex. Arabidopsis FT protein is widely regarded as the archetype florigen found in diverse plant species, particularly in plants that use inductive photoperiods to flower. Recently, a large family of FT homologues in maize, the Zea CENTRORADIALIS (ZCN) genes, was described, suggesting that maize also contains FT-related proteins that act as a florigen. The product of one member of this large family, ZCN8, has several attributes that make it a good candidate as a maize florigen. Mechanisms underlying the floral transition in maize are less well understood than those of other species, partly because flowering in temperate maize is dependent largely on endogenous signals. The maize indeterminate1 (id1) gene is an important regulator of maize autonomous flowering that acts in leaves to mediate the transmission or production of florigenic signals. This study finds that id1 acts upstream of ZCN8 to control its expression, suggesting a possible new link to flowering in day-neutral maize. Moreover, in teosinte, a tropical progenitor of maize that requires short-day photoperiods to induce flowering, ZCN8 is highly up-regulated in leaves under inductive photoperiods. Finally, vascular-specific expression of ZCN8 in Arabidopsis complements the ft-1 mutation, demonstrating that leaf-specific expression of ZCN8 can induce flowering. These results suggest that ZCN8 may encode a florigen that integrates both endogenous and environmental signals in maize.

  18. Photoperiodic regulation of flowering time through periodic histone deacetylation of the florigen gene FT.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Gu

    2013-09-01

    Full Text Available The developmental transition from a vegetative to a reproductive phase (i.e., flowering is timed by the seasonal cue day length or photoperiod in many plant species. Through the photoperiod pathway, inductive day lengths trigger the production of a systemic flowering signal, florigen, to provoke the floral transition. FLOWERING LOCUS T (FT, widely conserved in angiosperms, is a major component of the mobile florigen. In the long-day plant Arabidopsis, FT expression is rhythmically activated by the output of the photoperiod pathway CONSTANS (CO, specifically at the end of long days. How FT expression is modulated at an adequate level in response to the long-day cue to set a proper flowering time remains unknown. Here, we report a periodic histone deacetylation mechanism for the photoperiodic modulation of FT expression. We have identified a plant-unique core structural component of an Arabidopsis histone deacetylase (HDAC complex. In long days, this component accumulates at dusk, and is recruited by a MADS-domain transcription factor to the FT locus specifically at the end of the day, leading to periodic histone deacetylation of FT chromatin at dusk. Furthermore, we found that at the end of long days CO activity not only activates FT expression but also enables HDAC-activity recruitment to FT chromatin to dampen the level of FT expression, and so prevent precocious flowering in response to the inductive long-day cue. These results collectively reveal a periodic histone deacetylation mechanism for the day-length control of flowering time in higher plants.

  19. Photoperiodic regulation of flowering time through periodic histone deacetylation of the florigen gene FT.

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    Gu, Xiaofeng; Wang, Yizhong; He, Yuehui

    2013-09-01

    The developmental transition from a vegetative to a reproductive phase (i.e., flowering) is timed by the seasonal cue day length or photoperiod in many plant species. Through the photoperiod pathway, inductive day lengths trigger the production of a systemic flowering signal, florigen, to provoke the floral transition. FLOWERING LOCUS T (FT), widely conserved in angiosperms, is a major component of the mobile florigen. In the long-day plant Arabidopsis, FT expression is rhythmically activated by the output of the photoperiod pathway CONSTANS (CO), specifically at the end of long days. How FT expression is modulated at an adequate level in response to the long-day cue to set a proper flowering time remains unknown. Here, we report a periodic histone deacetylation mechanism for the photoperiodic modulation of FT expression. We have identified a plant-unique core structural component of an Arabidopsis histone deacetylase (HDAC) complex. In long days, this component accumulates at dusk, and is recruited by a MADS-domain transcription factor to the FT locus specifically at the end of the day, leading to periodic histone deacetylation of FT chromatin at dusk. Furthermore, we found that at the end of long days CO activity not only activates FT expression but also enables HDAC-activity recruitment to FT chromatin to dampen the level of FT expression, and so prevent precocious flowering in response to the inductive long-day cue. These results collectively reveal a periodic histone deacetylation mechanism for the day-length control of flowering time in higher plants.

  20. Geminivirus-mediated delivery of florigen promotes determinate growth in aerial organs and uncouples flowering from photoperiod in cotton.

    Directory of Open Access Journals (Sweden)

    Roisin C McGarry

    Full Text Available BACKGROUND: Plant architecture and the timing and distribution of reproductive structures are fundamental agronomic traits shaped by patterns of determinate and indeterminate growth. Florigen, encoded by FLOWERING LOCUS T (FT in Arabidopsis and SINGLE FLOWER TRUSS (SFT in tomato, acts as a general growth hormone, advancing determinate growth. Domestication of upland cotton (Gossypium hirsutum converted it from a lanky photoperiodic perennial to a highly inbred, compact day-neutral plant that is managed as an annual row-crop. This dramatic change in plant architecture provides a unique opportunity to analyze the transition from perennial to annual growth. METHODOLOGY/PRINCIPAL FINDINGS: To explore these architectural changes, we addressed the role of day-length upon flowering in an ancestral, perennial accession and in a domesticated variety of cotton. Using a disarmed Cotton leaf crumple virus (CLCrV as a transient expression system, we delivered FT to both cotton accessions. Ectopic expression of FT in ancestral cotton mimicked the effects of day-length, promoting photoperiod-independent flowering, precocious determinate architecture, and lanceolate leaf shape. Domesticated cotton infected with FT demonstrated more synchronized fruiting and enhanced "annualization". Transient expression of FT also facilitated simple crosses between wild photoperiodic and domesticated day-neutral accessions, effectively demonstrating a mechanism to increase genetic diversity among cultivated lines of cotton. Virus was not detected in the F(1 progeny, indicating that crosses made by this approach do not harbor recombinant DNA molecules. CONCLUSIONS: These findings extend our understanding of FT as a general growth hormone that regulates shoot architecture by advancing organ-specific and age-related determinate growth. Judicious manipulation of FT could benefit cotton architecture to improve crop management.

  1. Florigen signaling.

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    Tsuji, Hiroyuki; Taoka, Ken-Ichiro

    2014-01-01

    Florigen is a systemic signal that promotes flowering. Its molecular nature is a conserved FLOWERING LOCUS T (FT) protein that belongs to the PEBP family. FT is expressed in the leaf phloem and transported to the shoot apical meristem where it initiates floral transition. In the cells of the meristem, FT binds 14-3-3 proteins and bZIP transcription factor FD to form the florigen activation complex, FAC, which activates floral meristem identity genes such as AP1. The FAC model provides molecular basis for multiple functions of FT beyond flowering through changes of its partners and transcriptional targets. The surface of FT protein includes several regions essential for transport and functions, suggesting the binding of additional components that support its function. FT expression is under photoperiodic control, involving a conserved GIGANTEA-CONSTANS-FT regulatory module with species-specific modifications that contribute variations of flowering time in natural populations.

  2. Expression of a kinase-dead form of CPK33 involved in florigen complex formation causes delayed flowering.

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    Kawamoto, Nozomi; Endo, Motomu; Araki, Takashi

    2015-01-01

    Regulation of flowering time is crucial for reproductive success of plants. FLOWERING LOCUS T (FT) protein is a central component of florigen and forms a ternary complex with 14-3-3 and FD, a basic leucine zipper transcription factor, in the shoot apex and promotes flowering. This complex formation requires phosphorylation of threonine residue at position 282 of FD. A calcium-dependent protein kinase CPK33 is responsible for the phosphorylation. However, possibly due to functional redundancy among calcium-dependent protein kinases, impact of the loss of CPK33 reported in the previous study was rather limited. Here, we report that expression of a kinase-dead form of CPK33 caused a clear delayed-flowering phenotype, supporting for an important role of CPK33 in florigen function through FD phosphorylation.

  3. Structure and function of florigen and the receptor complex.

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    Taoka, Ken-ichiro; Ohki, Izuru; Tsuji, Hiroyuki; Kojima, Chojiro; Shimamoto, Ko

    2013-05-01

    In the 1930s, the flowering hormone, florigen, was proposed to be synthesized in leaves under inductive day length and transported to the shoot apex, where it induces flowering. More recently, generated genetic and biochemical data suggest that florigen is a protein encoded by the gene, FLOWERING LOCUS T (FT). A rice (Oryza sativa) FT homolog, Hd3a, interacts with the rice FD homolog, OsFD1, via a 14-3-3 protein. Formation of this tri-protein complex is essential for flowering promotion by Hd3a in rice. In addition, the multifunctionality of FT homologs, other than for flowering promotion, is an emerging concept. Here we review the structural and biochemical features of the florigen protein complex and discuss the molecular basis for the multifunctionality of FT proteins.

  4. CsTFL1, a constitutive local repressor of flowering, modulates floral initiation by antagonising florigen complex activity in chrysanthemum.

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    Higuchi, Yohei; Hisamatsu, Tamotsu

    2015-08-01

    Chrysanthemums require repeated cycles of short-day (SD) photoperiod for successful anthesis, but their vegetative state is strictly maintained under long-day (LD) or night-break (NB) conditions. We have previously demonstrated that photoperiodic flowering of a wild diploid chrysanthemum (Chrysanthemum seticuspe f. boreale) is controlled by a pair of systemic floral regulators, florigen (CsFTL3) and anti-florigen (CsAFT), produced in the leaves. Here, we report the functional characterisation of a local floral regulator, CsTFL1, a chrysanthemum orthologue of TERMINAL FLOWER 1 gene in Arabidopsis. Constitutive expression of CsTFL1 in C. seticuspe (CsTFL1-ox) resulted in extremely late flowering under SD and prevented up-regulation of floral meristem identity genes in shoot tips and leaves. Bimolecular fluorescence complementation assay showed that both CsTFL1 and CsFTL3 interacted with CsFDL1, a bZIP transcription factor FD homologue, in the nucleus. The transient gene expression assay indicated that CsTFL1 suppresses flowering by directly antagonising the flower inductive activity of the CsFTL3-CsFDL1 complex. Our results suggest that strict maintenance of vegetative state under non-inductive photoperiod is achieved by the coordinated action of both the systemic floral inhibitor and local floral inhibitor CsTFL1, which is constitutively expressed in shoot tips.

  5. Three FLOWERING LOCUS T-like genes function as potential florigens and mediate photoperiod response in sorghum.

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    Wolabu, Tezera W; Zhang, Fei; Niu, Lifang; Kalve, Shweta; Bhatnagar-Mathur, Pooja; Muszynski, Michael G; Tadege, Million

    2016-05-01

    Sorghum is a typical short-day (SD) plant and its use in grain or biomass production in temperate regions depends on its flowering time control, but the underlying molecular mechanism of floral transition in sorghum is poorly understood. Here we characterized sorghum FLOWERING LOCUS T (SbFT) genes to establish a molecular road map for mechanistic understanding. Out of 19 PEBP genes, SbFT1, SbFT8 and SbFT10 were identified as potential candidates for encoding florigens using multiple approaches. Phylogenetic analysis revealed that SbFT1 clusters with the rice Hd3a subclade, while SbFT8 and SbFT10 cluster with the maize ZCN8 subclade. These three genes are expressed in the leaf at the floral transition initiation stage, expressed early in grain sorghum genotypes but late in sweet and forage sorghum genotypes, induced by SD treatment in photoperiod-sensitive genotypes, cooperatively repressed by the classical sorghum maturity loci, interact with sorghum 14-3-3 proteins and activate flowering in transgenic Arabidopsis plants, suggesting florigenic potential in sorghum. SD induction of these three genes in sensitive genotypes is fully reversed by 1 wk of long-day treatment, and yet, some aspects of the SD treatment may still make a small contribution to flowering in long days, indicating a complex photoperiod response mediated by SbFT genes.

  6. 'Florigen' enters the molecular age: long-distance signals that cause plants to flower.

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    Colasanti, J; Sundaresan, V

    2000-05-01

    The transition from vegetative to reproductive growth is a critical event in the life cycle of plants. Previous physiological studies have deduced that hormone-like substances mediate this important transition but the biochemical nature of the putative signaling molecules has remained elusive. Recent molecular and genetic studies of key flowering-time genes offer new approaches to understanding the mechanisms underlying the initiation of flowering.

  7. Florigen in rice: complex gene network for florigen transcription, florigen activation complex, and multiple functions.

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    Tsuji, Hiroyuki; Taoka, Ken-ichiro; Shimamoto, Ko

    2013-05-01

    Regulation of flowering time directly influences successful rice grain production; thus, the long history of domestication and breeding has improved the genetic network of flowering. Recent advances using molecular genomic approaches have revealed the targets of these modifications and the underlying molecular mechanism for flowering. These efforts contributed to identifying the molecular nature of the systemic floral signal 'florigen' and have shown how florigen functions, how florigen expression is controlled, and how regulatory pathways are diversified. In this review, we summarize the advances in our understanding of the detailed molecular and genetic mechanisms that allow rice plants to produce flowers at the proper time to ensure grain production.

  8. A Blossoming Field of Research: How Florigen Is Transported to Create Flowers

    OpenAIRE

    Lu Liu; Chang Liu; Xingliang Hou; Wanyan Xi; Lisha Shen; Zhen Tao; Yue Wang; Hao Yu

    2012-01-01

    Author Summary The transition to flowering is the most dramatic phase change in flowering plants and is crucial for reproductive success. Such a transition from vegetative to reproductive growth is controlled by seasonal changes in day length. Studies originally performed in the 1930s were the first to suggest that day length is perceived by a plant's leaves; by contrast, flower formation takes place in the shoot apical meristem (the tip of the shoot that gives rise to plant organs, such as l...

  9. Emerging insights into florigen transport.

    Science.gov (United States)

    Liu, Lu; Zhu, Yang; Shen, Lisha; Yu, Hao

    2013-10-01

    The photoperiodic control of flowering in plants begins with the perception of seasonal changes in day length and consequential induction of a mobile floral stimulus in leaves. This stimulus called florigen is transported from leaves to the shoot apical meristem to provoke the initiation of floral meristems. Decades of efforts have identified that the proteins encoded by FLOWERING LOCUS T (FT) in Arabidopsis and its orthologs in other plant species are part of the long-sought florigen. Emerging evidence suggests that long-distance transport of FT towards the shoot apical meristem occurs through the phloem in a regulated manner. This review summarizes the recent advances in understanding florigen transport and discusses the proven and potential regulators required for this process.

  10. 高等植物中的成花素及其对成花的诱导%Florigen in Higher Plants and Its Induction of Flowering

    Institute of Scientific and Technical Information of China (English)

    莫旭东; 成平; 覃磊; 张小波; 夏石头

    2016-01-01

    Flowering is an important process of transformation from vegetative growth to reproductive growth in higher plants which is regulated by both inside and environmental factors.As a core element in the regulation process of flowering,flori-gen plays an important role in the whole process of plant reproduction and development.The main research progress inclu-ding the early study of florigen in higher plants,the discovery of flowering locus T (FT)and its homologous protein,their transportation in phloem,mechanism of induction and regulation of flowering are introduced in the paper.%成花是高等植物由营养生长到生殖生长转变的一个重要环节,受到各种内部因素和外部环境的调节。成花素作为调节植物成花的核心元素,对植物的生殖和发育起着重要作用。主要介绍了高等植物中成花素的早期研究、FT 及其同源基因蛋白的发现,其在韧皮部的转运、对成花的诱导及其调控成花的机理等方面的研究进展。

  11. The 14-3-3 protein GF14c acts as a negative regulator of flowering in rice by interacting with the florigen Hd3a.

    Science.gov (United States)

    Purwestri, Yekti Asih; Ogaki, Yuka; Tamaki, Shojiro; Tsuji, Hiroyuki; Shimamoto, Ko

    2009-03-01

    Hd3a and FT proteins have recently been proposed to act as florigens in rice and Arabidopsis, respectively; however, the molecular mechanisms of their function remain to be determined. In this study, we identified GF14c (a 14-3-3 protein) as an Hd3a-interacting protein in a yeast two-hybrid screen. In vitro and in vivo experiments, using a combination of pull-down assays and bimolecular fluorescence complementation, confirmed the interaction between Hd3a and GF14c. Functional analysis using either GF14c overexpression or knockout transgenic rice plants indicated that this interaction plays a role in the regulation of flowering. GF14c-overexpressing plants exhibited a delay in flowering and the knockout mutants displayed early flowering relative to the wild-type plants under short-day conditions. These results suggest that GF14c acts as a negative regulator of flowering by interacting with Hd3a. Since the 14-3-3 protein has been shown to interact with FT protein in tomato and Arabidopsis, our results in rice provide important findings about FT signaling in plants.

  12. Tomato yield heterosis is triggered by a dosage sensitivity of the florigen pathway that fine-tunes shoot architecture.

    Science.gov (United States)

    Jiang, Ke; Liberatore, Katie L; Park, Soon Ju; Alvarez, John P; Lippman, Zachary B

    2013-01-01

    The superiority of hybrids has long been exploited in agriculture, and although many models explaining "heterosis" have been put forth, direct empirical support is limited. Particularly elusive have been cases of heterozygosity for single gene mutations causing heterosis under a genetic model known as overdominance. In tomato (Solanum lycopersicum), plants carrying mutations in SINGLE FLOWER TRUSS (SFT) encoding the flowering hormone florigen are severely delayed in flowering, become extremely large, and produce few flowers and fruits, but when heterozygous, yields are dramatically increased. Curiously, this overdominance is evident only in the background of "determinate" plants, in which the continuous production of side shoots and inflorescences gradually halts due to a defect in the flowering repressor SELF PRUNING (SP). How sp facilitates sft overdominance is unclear, but is thought to relate to the opposing functions these genes have on flowering time and shoot architecture. We show that sft mutant heterozygosity (sft/+) causes weak semi-dominant delays in flowering of both primary and side shoots. Using transcriptome sequencing of shoot meristems, we demonstrate that this delay begins before seedling meristems become reproductive, followed by delays in subsequent side shoot meristems that, in turn, postpone the arrest of shoot and inflorescence production. Reducing SFT levels in sp plants by artificial microRNAs recapitulates the dose-dependent modification of shoot and inflorescence production of sft/+ heterozygotes, confirming that fine-tuning levels of functional SFT transcripts provides a foundation for higher yields. Finally, we show that although flowering delays by florigen mutant heterozygosity are conserved in Arabidopsis, increased yield is not, likely because cyclical flowering is absent. We suggest sft heterozygosity triggers a yield improvement by optimizing plant architecture via its dosage response in the florigen pathway. Exploiting dosage

  13. Tomato yield heterosis is triggered by a dosage sensitivity of the florigen pathway that fine-tunes shoot architecture.

    Directory of Open Access Journals (Sweden)

    Ke Jiang

    Full Text Available The superiority of hybrids has long been exploited in agriculture, and although many models explaining "heterosis" have been put forth, direct empirical support is limited. Particularly elusive have been cases of heterozygosity for single gene mutations causing heterosis under a genetic model known as overdominance. In tomato (Solanum lycopersicum, plants carrying mutations in SINGLE FLOWER TRUSS (SFT encoding the flowering hormone florigen are severely delayed in flowering, become extremely large, and produce few flowers and fruits, but when heterozygous, yields are dramatically increased. Curiously, this overdominance is evident only in the background of "determinate" plants, in which the continuous production of side shoots and inflorescences gradually halts due to a defect in the flowering repressor SELF PRUNING (SP. How sp facilitates sft overdominance is unclear, but is thought to relate to the opposing functions these genes have on flowering time and shoot architecture. We show that sft mutant heterozygosity (sft/+ causes weak semi-dominant delays in flowering of both primary and side shoots. Using transcriptome sequencing of shoot meristems, we demonstrate that this delay begins before seedling meristems become reproductive, followed by delays in subsequent side shoot meristems that, in turn, postpone the arrest of shoot and inflorescence production. Reducing SFT levels in sp plants by artificial microRNAs recapitulates the dose-dependent modification of shoot and inflorescence production of sft/+ heterozygotes, confirming that fine-tuning levels of functional SFT transcripts provides a foundation for higher yields. Finally, we show that although flowering delays by florigen mutant heterozygosity are conserved in Arabidopsis, increased yield is not, likely because cyclical flowering is absent. We suggest sft heterozygosity triggers a yield improvement by optimizing plant architecture via its dosage response in the florigen pathway

  14. Florigens and antiflorigens: a molecular genetic understanding.

    Science.gov (United States)

    Matsoukas, Ianis G

    2015-01-01

    Florigens, the leaf-derived signals that initiate flowering, have been described as 'mysterious', 'elusive' and the 'Holy Grail' of plant biology. They are synthesized in response to appropriate photoperiods and move through the phloem tissue. It has been proposed that their composition is complex. The evidence that flowering locus T (FT) protein and its paralogue twin sister of FT (TSF) act as florigen, or represent at least part of it, in diverse plant species has attracted considerable attention. In Arabidopsis thaliana, inductive photoperiodic conditions perceived in the leaf lead to stabilization of CONSTANS protein, which induces FT and TSF transcription. When they have been translated in the phloem companion cells, FT and TSF enter the phloem stream and are conveyed to the shoot apical meristem, where they act together with flowering locus D to activate transcription of floral meristem identity genes, resulting in floral initiation. At least part of this model is conserved, with some variations in several species. In addition to florigen(s), a systemic floral inhibitor or antiflorigen contributes to floral initiation. This chapter provides an overview of the different molecules that have been demonstrated to have florigenic or antiflorigenic functions in plants, and suggests possible directions for future research.

  15. Florigen is involved in axillary bud development at multiple stages in Arabidopsis.

    Science.gov (United States)

    Niwa, Masaki; Endo, Motomu; Araki, Takashi

    2013-11-01

    The wide variety of plant architectures is largely based on diverse and flexible modes of axillary shoot development. In Arabidopsis, floral transition (flowering) stimulates axillary bud development. The mechanism that links flowering and axillary bud development is, however, largely unknown. We recently showed that FLOWERING LOCUS T (FT) protein, which acts as florigen, promotes the phase transition of axillary meristems, whereas BRANCHED1 (BRC1) antagonizes the florigen action in axillary buds. Here, we present evidences for another possible role of florigen in axillary bud development. Ectopic overexpression of FT or another florigen gene TWIN SISTER OF FT (TSF) with LEAFY (LFY) induces ectopic buds at cotyledonary axils, confirming the previous proposal that these genes are involved in formation of axillary buds. Taken together with our previous report that florigen promotes axillary shoot elongation, we propose that florigen regulates axillary bud development at multiple stages to coordinate it with flowering in Arabidopsis.

  16. Florigen (Ⅱ): It is a Mobile Protein

    Institute of Scientific and Technical Information of China (English)

    Yuejun Yang; John Klejnot; Xuhong Yu; Xuanming Liu; Chentao Lin

    2007-01-01

    The true Identity of florigen - the molecule(s) that migrates from leaves to apical meristem to initiate flowering - was notoriously elusive, having made it almost the "Bigfoot" of plant biology.There was never a lack of drama in the field of florigen study, and fiorigen researchers have once again experienced such a swing in the last two years.We wrote a minirsview last year in this journal (Yu et al.2006) to excitedly salute, among other discoveries, the notion that the flowering locus T (FT) mRNA might be the molecular form of a florigen.However, this hypothesis was challenged in a little less than two years after its initial proposition, and the original paper proposed that the FT mRNA hypothesis was retracted (Huang et al.2005; Bohlenlus et al.2007).Interestingly enough, the FT gene previously proposed to encode a florigen was never challenged.Rather, the FT protein, instead of the FT mRNA, Is now believed to migrate from leaves to the apical meristem to promote floral initiation.In this update, we will share with our readers some entertaining stories concerning the recent studies of florigen in five different plant species.In addition to the published reports referenced in this update, readers may also refer to our previous minireview and references therein for additional background Information (Yu et al.2006).

  17. Functional diversification of FD transcription factors in rice, components of florigen activation complexes.

    Science.gov (United States)

    Tsuji, Hiroyuki; Nakamura, Hiroyuki; Taoka, Ken-ichiro; Shimamoto, Ko

    2013-03-01

    Florigen, a protein encoded by the FLOWERING LOCUS T (FT) in Arabidopsis and Heading date 3a (Hd3a) in rice, is the universal flowering hormone in plants. Florigen is transported from leaves to the shoot apical meristem and initiates floral evocation. In shoot apical cells, conserved cytoplasmic 14-3-3 proteins act as florigen receptors. A hexameric florigen activation complex (FAC) composed of Hd3a, 14-3-3 proteins, and OsFD1, a transcription factor, activates OsMADS15, a rice homolog of Arabidopsis APETALA1, leading to flowering. Because FD is a key component of the FAC, we characterized the FD gene family and their functions. Phylogenetic analysis of FD genes indicated that this family is divided into two groups: (i) canonical FD genes that are conserved among eudicots and non-Poaceae monocots; and (ii) Poaceae-specific FD genes that are organized into three subgroups: Poaceae FD1, FD2 and FD3. The Poaceae FD1 group shares a small sequence motif, T(A/V)LSLNS, with FDs of eudicots and non-Poaceae monocots. Overexpression of OsFD2, a member of the Poaceae FD2 group, produced smaller leaves with shorter plastochrons, suggesting that OsFD2 controls leaf development. In vivo subcellular localization of Hd3a, 14-3-3 and OsFD2 suggested that in contrast to OsFD1, OsFD2 is restricted to the cytoplasm through its interaction with the cytoplasmic 14-3-3 proteins, and interaction of Hd3a with 14-3-3 facilitates nuclear translocation of the FAC containing OsFD2. These results suggest that FD function has diverged between OsFD1 and OsFD2, but formation of a FAC is essential for their function.

  18. Optimization of crop productivity in tomato using induced mutations in the florigen pathway.

    Science.gov (United States)

    Park, Soon Ju; Jiang, Ke; Tal, Lior; Yichie, Yoav; Gar, Oron; Zamir, Dani; Eshed, Yuval; Lippman, Zachary B

    2014-12-01

    Naturally occurring genetic variation in the universal florigen flowering pathway has produced major advancements in crop domestication. However, variants that can maximize crop yields may not exist in natural populations. Here we show that tomato productivity can be fine-tuned and optimized by exploiting combinations of selected mutations in multiple florigen pathway components. By screening for chemically induced mutations that suppress the bushy, determinate growth habit of field tomatoes, we isolated a new weak allele of the florigen gene SINGLE FLOWER TRUSS (SFT) and two mutations affecting a bZIP transcription factor component of the 'florigen activation complex' (ref. 11). By combining heterozygous mutations, we pinpointed an optimal balance of flowering signals, resulting in a new partially determinate architecture that translated to maximum yields. We propose that harnessing mutations in the florigen pathway to customize plant architecture and flower production offers a broad toolkit to boost crop productivity.

  19. Florigen is involved in axillary bud development at multiple stages in Arabidopsis

    OpenAIRE

    Niwa, Masaki; Endo, Motomu; Araki, Takashi

    2013-01-01

    The wide variety of plant architectures is largely based on diverse and flexible modes of axillary shoot development. In Arabidopsis, floral transition (flowering) stimulates axillary bud development. The mechanism that links flowering and axillary bud development is, however, largely unknown. We recently showed that FLOWERING LOCUS T (FT) protein, which acts as florigen, promotes the phase transition of axillary meristems, whereas BRANCHED1 (BRC1) antagonizes the florigen action in axillary ...

  20. 14-3-3 proteins act as intracellular receptors for rice Hd3a florigen.

    Science.gov (United States)

    Taoka, Ken-ichiro; Ohki, Izuru; Tsuji, Hiroyuki; Furuita, Kyoko; Hayashi, Kokoro; Yanase, Tomoko; Yamaguchi, Midori; Nakashima, Chika; Purwestri, Yekti Asih; Tamaki, Shojiro; Ogaki, Yuka; Shimada, Chihiro; Nakagawa, Atsushi; Kojima, Chojiro; Shimamoto, Ko

    2011-07-31

    'Florigen' was proposed 75 years ago to be synthesized in the leaf and transported to the shoot apex, where it induces flowering. Only recently have genetic and biochemical studies established that florigen is encoded by FLOWERING LOCUS T (FT), a gene that is universally conserved in higher plants. Nonetheless, the exact function of florigen during floral induction remains poorly understood and receptors for florigen have not been identified. Here we show that the rice FT homologue Hd3a interacts with 14-3-3 proteins in the apical cells of shoots, yielding a complex that translocates to the nucleus and binds to the Oryza sativa (Os)FD1 transcription factor, a rice homologue of Arabidopsis thaliana FD. The resultant ternary 'florigen activation complex' (FAC) induces transcription of OsMADS15, a homologue of A. thaliana APETALA1 (AP1), which leads to flowering. We have determined the 2.4 Å crystal structure of rice FAC, which provides a mechanistic basis for florigen function in flowering. Our results indicate that 14-3-3 proteins act as intracellular receptors for florigen in shoot apical cells, and offer new approaches to manipulate flowering in various crops and trees.

  1. Florigenic and antiflorigenic signaling in plants.

    Science.gov (United States)

    Matsoukas, Ianis G; Massiah, Andrea J; Thomas, Brian

    2012-11-01

    The evidence that FLOWERING LOCUS T (FT) protein, and its paralog TWIN SISTER OF FT, act as the long-distance floral stimulus, or at least that they are part of it in diverse plant species, has attracted much attention in recent years. Studies to understand the physiological and molecular apparatuses that integrate spatial and temporal signals to regulate developmental transitions in plants have occupied countless scientists and have resulted in an unmanageably large amount of research data. Analysis of these data has helped to identify multiple systemic florigenic and antiflorigenic regulators. This study gives an overview of the recent research on gene products, phytohormones and other metabolites that have been demonstrated to have florigenic or antiflorigenic functions in plants.

  2. 揭开植物开花之谜——成花素的发现%Identification of Florigen in Flowering Plants

    Institute of Scientific and Technical Information of China (English)

    王团宗; 李师鹏

    2007-01-01

    开花现象是绿色开花植物所特有的,对其机理的研究一直是生物学学家极为关注的研究领域.成花素假说认为植物叶片在光的诱导下产生一种叫成花素(Florigen)的分子,成花素可以运输到植物茎顶端诱导花芽的分化,但是成花素的化学本质一直没有被鉴定.最近发现成花素是一种叫做FT的蛋白分子,该分子广泛存在于植物界参与花器官的诱导,至此,成花素假说不再是假说.回顾了成花素假说形成的历史,介绍成花素发现的最新成果.

  3. FTIP1 is an essential regulator required for florigen transport.

    Directory of Open Access Journals (Sweden)

    Lu Liu

    Full Text Available The capacity to respond to day length, photoperiodism, is crucial for flowering plants to adapt to seasonal change. The photoperiodic control of flowering in plants is mediated by a long-distance mobile floral stimulus called florigen that moves from leaves to the shoot apex. Although the proteins encoded by FLOWERING LOCUS T (FT in Arabidopsis and its orthologs in other plants are identified as the long-sought florigen, whether their transport is a simple diffusion process or under regulation remains elusive. Here we show that an endoplasmic reticulum (ER membrane protein, FT-INTERACTING PROTEIN 1 (FTIP1, is an essential regulator required for FT protein transport in Arabidopsis. Loss of function of FTIP1 exhibits late flowering under long days, which is partly due to the compromised FT movement to the shoot apex. FTIP1 and FT share similar mRNA expression patterns and subcellular localization, and they interact specifically in phloem companion cells. FTIP1 is required for FT export from companion cells to sieve elements, thus affecting FT transport through the phloem to the SAM. Our results provide a mechanistic understanding of florigen transport, demonstrating that FT moves in a regulated manner and that FTIP1 mediates FT transport to induce flowering.

  4. FTIP1 is an essential regulator required for florigen transport.

    Science.gov (United States)

    Liu, Lu; Liu, Chang; Hou, Xingliang; Xi, Wanyan; Shen, Lisha; Tao, Zhen; Wang, Yue; Yu, Hao

    2012-01-01

    The capacity to respond to day length, photoperiodism, is crucial for flowering plants to adapt to seasonal change. The photoperiodic control of flowering in plants is mediated by a long-distance mobile floral stimulus called florigen that moves from leaves to the shoot apex. Although the proteins encoded by FLOWERING LOCUS T (FT) in Arabidopsis and its orthologs in other plants are identified as the long-sought florigen, whether their transport is a simple diffusion process or under regulation remains elusive. Here we show that an endoplasmic reticulum (ER) membrane protein, FT-INTERACTING PROTEIN 1 (FTIP1), is an essential regulator required for FT protein transport in Arabidopsis. Loss of function of FTIP1 exhibits late flowering under long days, which is partly due to the compromised FT movement to the shoot apex. FTIP1 and FT share similar mRNA expression patterns and subcellular localization, and they interact specifically in phloem companion cells. FTIP1 is required for FT export from companion cells to sieve elements, thus affecting FT transport through the phloem to the SAM. Our results provide a mechanistic understanding of florigen transport, demonstrating that FT moves in a regulated manner and that FTIP1 mediates FT transport to induce flowering.

  5. Developing a method for customized induction of flowering

    Directory of Open Access Journals (Sweden)

    Macknight Richard

    2011-04-01

    Full Text Available Abstract Background The ability to induce flowering on demand is of significant biotechnological interest. FT protein has been recently identified as an important component of the mobile flowering hormone, florigen, whose function is conserved across the plant kingdom. We therefore focused on manipulation of both endogenous and heterologous FT genes to develop a floral induction system where flowering would be inhibited until it was induced on demand. The concept was tested in the model plant Arabidopsis thaliana (Arabidopsis. Results Our starting point was plants with strongly delayed flowering due to silencing of FT with an artificial microRNA directed at FT (amiR-FT 1. First, we showed that constitutive expression of a heterologous FT gene (FTa1, from the model legume Medicago truncatula, (Medicago was able to rescue the amiR-FT late-flowering phenotype. In order to induce flowering in a controlled way, the FTa1 gene was then expressed under the control of an alcohol-inducible promoter in the late flowering amiR-FT plants. Upon exposure to ethanol, FTa1 was rapidly up regulated and this resulted in the synchronous induction of flowering. Conclusions We have thus demonstrated a controlled-inducible flowering system using a novel combination of endogenous and heterologous FT genes. The universal florigenic nature of FT suggests that this type of system should be applicable to crops of economic value where flowering control is desirable.

  6. The florigen genes FT and TSF modulate lateral shoot outgrowth in Arabidopsis thaliana.

    Science.gov (United States)

    Hiraoka, Kazuhisa; Yamaguchi, Ayako; Abe, Mitsutomo; Araki, Takashi

    2013-03-01

    Successful sexual reproduction of a plant with prolific seed production requires appropriate timing of flowering and concomitant change of architecture (e.g. internode elongation and branching) to facilitate production of the optimal number of flowers while enabling continued resource production through photosynthesis. Florigen is the prime candidate for a signal linking the two processes. Growth analysis of lateral shoots in mutants of FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) revealed a delay in the onset of outgrowth and a reduction of the growth rate in ft plants in long-day (LD) conditions and in tsf plants in short-day (SD) conditions. Thus, as in the case of floral transition, FT and TSF play dominant roles in LD and SD conditions, respectively, in the promotion of lateral shoot development. Differential expression patterns of the two genes were in good agreement with their differential roles both in the floral transition and in lateral shoot development under contrasting photoperiod conditions. By manipulating florigen production after bolting of the primary shoot, it was shown that florigen promotes lateral shoot growth independently of its effect on the floral transition of the primary shoot. Analysis of growth and gene expression in lateral shoots of the mutants suggests that the loss of florigen leads to a reduced rate of flower formation on lateral shoots. Together, we propose that the two florigen genes are an important key to linking the floral transition and lateral shoot development to maximize the reproductive success of a plant.

  7. The florigen mystery

    OpenAIRE

    E.G. Groenewald; A.J. Van Der Westhuizen

    2006-01-01

    In order to obtain flowering, different applications of chemicals on plants were tested by several researchers. Substances that were tested were, amongst others, auxin, gibberellin, cytokinin, abscisic acid, prostaglandin; melatonin. All had an effect on flowering. With the aid of molecular-genetic research it was established that the product of certain genes, namely CONSTANS (CO) and FLOWERING LOCUS T (FT) could be the flowering stimulus. It could be a peptide or mRNA.

  8. The florigen mystery

    Directory of Open Access Journals (Sweden)

    E.G. Groenewald

    2006-09-01

    Full Text Available In order to obtain flowering, different applications of chemicals on plants were tested by several researchers. Substances that were tested were, amongst others, auxin, gibberellin, cytokinin, abscisic acid, prostaglandin; melatonin. All had an effect on flowering. With the aid of molecular-genetic research it was established that the product of certain genes, namely CONSTANS (CO and FLOWERING LOCUS T (FT could be the flowering stimulus. It could be a peptide or mRNA.

  9. Florigen: One Found, More to Follow?

    Institute of Scientific and Technical Information of China (English)

    Xuhong Yu; John Klejnot; Chentao Lin

    2006-01-01

    Florigen(s) are molecules that are synthesized in response to appropriate photoperiods and transmitted from leaves to shoot apices to promote floral initiation. It has been recently discovered in Arabidopsis that mRNA of the FT gene acts as a florigen. In Arabidopsis, cryptochromes and phytochromes mediate longday promotion of CO protein expression, which activates FT mRNA expression in leaves. FT mRNA is transmitted to the shoot apex, where it acts together with FD to activate transcription of floral meristem identity genes, resulting in floral initiation. The discovery of the molecular nature of a florigen was a major scientific breakthrough in 2005.

  10. GIGANTEA enables drought escape response via abscisic acid-dependent activation of the florigens and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS.

    Science.gov (United States)

    Riboni, Matteo; Galbiati, Massimo; Tonelli, Chiara; Conti, Lucio

    2013-07-01

    Modulation of the transition to flowering plays an important role in the adaptation to drought. The drought-escape (DE) response allows plants to adaptively shorten their life cycle to make seeds before severe stress leads to death. However, the molecular basis of the DE response is unknown. A screen of different Arabidopsis (Arabidopsis thaliana) flowering time mutants under DE-triggering conditions revealed the central role of the flower-promoting gene GIGANTEA (GI) and the florigen genes FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) in the DE response. Further screens showed that the phytohormone abscisic acid is required for the DE response, positively regulating flowering under long-day conditions. Drought stress promotes the transcriptional up-regulation of the florigens in an abscisic acid- and photoperiod-dependent manner, so that early flowering only occurs under long days. Along with the florigens, the floral integrator SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 is also up-regulated in a similar fashion and contributes to the activation of TSF. The DE response was recovered under short days in the absence of the floral repressor SHORT VEGETATIVE PHASE or in GI-overexpressing plants. Our data reveal a key role for GI in connecting photoperiodic cues and environmental stress independently from the central FT/TSF activator CONSTANS. This mechanism explains how environmental cues may act upon the florigen genes in a photoperiodically controlled manner, thus enabling plastic flowering responses.

  11. The influence of heterostyly, pollination method and hormonization on eggplant's (Solanum melongena L. flowering and fruiting

    Directory of Open Access Journals (Sweden)

    Grażyna Kowalska

    2013-12-01

    Full Text Available The experiment was carried out in a three unheated plastic tunnels in 1998-2000. The aim of this study was to estimate the effects of flower's heterostyly and two methods of flower pollination (self-pollination and using bumble-bee as well as flower hormonization on the flowering and fruiting of three varieties of aubergine - 'Black Beauty', 'Solara F1 and Epic F1' The analysis of results showed that the eggplants formed more flowers in object with self-pollination and flower hormonization than those pollinated by bumble-bee. Regardless of the pollination way and flower hormonization, eggplants formed the highest number of flowers with long pistil and much less - with medium and short pistil. It was shown that the tendency to formation the flowers with particular type of pistil is the variety trait of eggplants. The highest number of flowers with long pistil was observed in varieties 'Solara F1' and 'Epic F1' and those with medium pistil - in 'Black Beauty' variety. Heterostyly phenomenon occurring in eggplant's flowers affected the plant's fruiting. The most fruits were set from flowers with long pistils than from those with medium and short ones. Fruits formed from long pistil flowers were characterized with significantly greater mean weight and size, than those formed from medium and short pistil ones. No significant influence of pollination method on eggplant fruit quality was found in three years of study. Fruits achieved due to three pollination methods were characterized with similar mean weight and diameter. Fruits with significantly larger mean length were achieved from flowers pollinated by bumble-bees than from self - pollinated ones.

  12. Photoperiodic Regulation of Florigen Function in Arabidopsis thaliana.

    Science.gov (United States)

    Golembeski, Greg S; Imaizumi, Takato

    2015-01-01

    One mechanism through which flowering in response to seasonal change is brought about is by sensing the fluctuation in day-length; the photoperiod. Flowering induction occurs through the production of the florigenic protein FLOWERING LOCUS T (FT) and its movement from the phloem companion cells in the leaf vasculature into the shoot apex, where meristematic reprogramming occurs. FT activation in response to photoperiod condition is accomplished largely through the activity of the transcription factor CONSTANS (CO). Regulation of CO expression and protein stability, as well as the timing of other components via the circadian clock, is a critical mechanism by which plants are able to respond to photoperiod to initiate the floral transition. Modulation of FT expression in response to external and internal stimuli via components of the flowering network is crucial to mediate a fluid flowering response to a variety of environmental parameters. In addition, the regulated movement of FT protein from the phloem to the shoot apex, and interactions that determine floral meristem cell fate, constitute novel mechanisms through which photoperiodic information is translated into flowering time.

  13. Mobile FT mRNA contributes to the systemic florigen signalling in floral induction.

    Science.gov (United States)

    Li, Chunyang; Gu, Mei; Shi, Nongnong; Zhang, Hang; Yang, Xin; Osman, Toba; Liu, Yule; Wang, Huizhong; Vatish, Manu; Jackson, Stephen; Hong, Yiguo

    2011-01-01

    In inducing photoperiodic conditions, plants produce a signal dubbed "florigen" in leaves. Florigen moves through the phloem to the shoot apical meristem (SAM) where it induces flowering. In Arabidopsis, the FLOWERING LOCUS T (FT) protein acts as a component of this phloem-mobile signal. However whether the transportable FT mRNA also contributes to systemic florigen signalling remains to be elucidated. Using non-conventional approaches that exploit virus-induced RNA silencing and meristem exclusion of virus infection, we demonstrated that the ArabidopsisFT mRNA, independent of the FT protein, can move into the SAM. Viral ectopic expression of a non-translatable FT mRNA promoted earlier flowering in the short-day (SD) Nicotiana tabacum Maryland Mammoth tobacco in SD. These data suggest a possible role for FT mRNA in systemic floral signalling, and also demonstrate that cis-transportation of cellular mRNA into SAM and meristem exclusion of pathogenic RNAs are two mechanistically distinct processes.

  14. Early histological, hormonal, and molecular changes during pineapple (Ananas comosus (L.) Merrill) artificial flowering induction.

    Science.gov (United States)

    Espinosa, Maita Eulalia Ávila; Moreira, Rafael Oliveira; Lima, André Almeida; Ságio, Solange Aparecida; Barreto, Horllys Gomes; Luiz, Sara Lazara Pérez; Abreu, Carlos Eduardo Aragón; Yanes-Paz, Ermis; Ruíz, Yanelis Capdesuñer; González-Olmedo, Justo Lorenzo; Chalfun-Júnior, Antonio

    2017-02-01

    Natural flowering can cause serious scheduling problems in the pineapple (Ananas comosus) industry and increase harvest costs. Pineapple flowering is thought to be triggered by increased ethylene levels and artificial forcing of pineapple flowering is a common practice to promote flowering synchronisation. However, little is known about the early hormonal and molecular changes of pineapple flowering induction and development. Here, we aimed to analyse the molecular, hormonal, and histological changes during artificial pineapple flowering by Ethrel(®)48 treatment. Histological analyses of the shoot apical meristem, leaf gibberellic acid (GA3), and ethylene quantification were carried out during the first 72h after Ethrel(®)48 treatment. Expression profiles from ethylene biosynthesis (AcACS2 and AcACO1), gibberellin metabolism (AcGA2-ox1 and AcDELLA1), and flower development (FT-like gene (AcFT), LFY-like gene (AcLFY), and a PISTILLATA-like gene (AcPI)) genes were analysed during the first 24h after Ethrel(®)48 treatment. Differentiation processes of the shoot apical meristem into flower buds were already present in the first 72h after Ethrel(®)48 treatment. Ethrel(®)48 lead to a reduction in GA3 levels, probably triggered by elevated ethylene levels and the positive regulation AcGA2-ox1. AcLFY activation upon Ethrel(®)48 may also have contributed to the reduction of GA3 levels and, along with the up-regulation of AcPI, are probably associated with the flower induction activation. AcFT and AcDELLA1 do not seem to be regulated by GA3 and ethylene. Decreased GA3 and increased ethylene levels suggest an accumulation of AcDELLA1, which may display an important role in pineapple flowering induction. Thus, this study shows that molecular, hormonal, and histological changes are present right after Ethrel(®)48 treatment, providing new insights into how pineapple flowering occurs under natural conditions.

  15. The coincidence of critical day length recognition for florigen gene expression and floral transition under long-day conditions in rice.

    Science.gov (United States)

    Itoh, Hironori; Izawa, Takeshi

    2013-05-01

    The photoperiodic control of flowering time is essential for the adaptation of plants to variable environments and for successful reproduction. The identification of genes encoding florigens, which had been elusive but were supposedly synthesized in leaves and then transmitted to shoot apices to induce floral transitions, has greatly advanced our understanding of the photoperiodic regulation of flowering. Studies on the photoperiodism of Arabidopsis, a model long-day plant, revealed the molecular mechanisms regulating the expression of the Arabidopsis florigen gene FT, which is gradually induced in response to increase in day length. By contrast, in rice, a model short-day plant, the expression of the florigen gene Hd3a (an FT ortholog in rice) is regulated in an on/off fashion, with strong induction under short-day conditions and repression under long-day conditions. This critical day length dependence of Hd3a expression enables rice to recognize a slight change in the photoperiod as a trigger to initiate floral induction. Rice possesses a second florigen gene, RFT1, which can be expressed to induce floral transition under non-inductive long-day conditions. The complex transcriptional regulation of florigen genes and the resulting precise control over flowering time provides rice with the adaptability required for a crop species of increasing global importance.

  16. Florigen distribution determined by a source-sink balance explains the diversity of inflorescence structures in Arabidopsis.

    Science.gov (United States)

    Satake, Akiko; Seki, Motohide; Iima, Makoto; Teramoto, Takashi; Nishiura, Yasumasa

    2016-04-21

    The ability to continue flowering after loss of inductive environmental cues that trigger flowering is termed floral commitment. Reversible transition involving a switch from floral development back to vegetative development has been found in Arabidopsis mutants and many plant species. Although the molecular basis for floral commitment remains unclear, recent studies suggest that the persistent activity of FLOWERING LOCUS T (FT) at inflorescences is required for floral commitment in Arabidopsis thaliana. Because FT encodes a mobile signal, florigen, which is generally transported from leaves to meristems through the phloem, understanding the transportation dynamics of FT is required to explore the role of FT on floral commitment. Here we developed a transportation model of leaf- and inflorescence-derived florigen and sucrose based on pressure-flow hypothesis. Depending on the demanded level of florigen supply for floral commitment of each floral meristem, the model predicted the change in inflorescence pattern from stable commitment to flower, transient flowering, and complete reversion. FT activity in inflorescence partly suppressed floral reversion, but complete suppression was achieved only when inflorescence became a source of sucrose. This finding highlights the importance of monitoring the spatio-temporal sucrose distribution and floral stimulus to understand inflorescence development mechanism.

  17. The quest for florigen: a review of recent progress.

    Science.gov (United States)

    Corbesier, Laurent; Coupland, George

    2006-01-01

    The photoperiodic induction of flowering is a systemic process requiring translocation of a floral stimulus from the leaves to the shoot apical meristem. In response to this stimulus, the apical meristem stops producing leaves to initiate floral development; this switch in morphogenesis involves a change in the identity of the primordia initiated and in phyllotaxis. The physiological study of the floral transition has led to the identification of several putative floral signals such as sucrose, cytokinins, gibberellins, and reduced N-compounds that are translocated in the phloem sap from leaves to the shoot apical meristem. On the other hand, the genetic approach developed more recently in Arabidopsis thaliana allowed the discovery of many genes that control flowering time. These genes function in 'cascades' within four promotive pathways, the 'photoperiodic', 'autonomous', 'vernalization', and 'gibberellin' pathways, which all converge on the 'integrator' genes SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) and FLOWERING LOCUS T (FT). Recently, several studies have highlighted a role for a product of FT as a component of the floral stimulus or 'florigen'. These recent advances and the proposed mode of action of FT are discussed here.

  18. Isolation of Florigen Gene PdFT and Its Effects on Flowering of Tree Peony(Paeonia delavayi Franch.)%成花素基因PdFT的克隆及其对牡丹成花的影响

    Institute of Scientific and Technical Information of China (English)

    朱富勇; 刘传娇; 薛璟祺; 王顺利; 张萍; 任秀霞; 张秀新

    2014-01-01

    Objective The objective of this study was to clone the homolog of FT gene from tree peony and analyze the expression pattern and the potential function of flowering locus T (FT) of flowering in Paeonia delavayi Franch..[Method]The homologous FT gene, PdFT, was cloned by reverse transcript polymerase chain reaction (RT-PCR). The expression patterns of PdFT in different organs, developmental stages of flowering and treatments of P. delavayi Franch. were analyzed by using qRT-PCR and the relationship between the PdFT expression level and the different states of flower bud development was also studied. At the same time, PdFT was inserted into vector pET-28a and expressed in E. coli BL21 (DE3). [Result]The full length of open reading frame (ORF) of PdFT was 522 bp, encoding 173 amino acid residues. The GenBank accession number is KF113360. Alignment of the AA sequences revealed that PdFT contains a conserved domain, which possesses the characteristics of the PEBP family. The result also suggested that PdFT shares high identity with FT proteins from other plants. qRT-PCR analysis of PdFT expression pattern in different organs showed that the highest expression levels were appeared in the buds of P. delavayi, followed by roots, stems and leaves. The expression pattern of PdFT from bud swelling to big-like flower-bud showed a decreased trend. The expression level of PdFT under long day condition was higher than that under short day condition. Cool treatment could decrease PdFT expression in roots and stems. The expression of PdFT under different floral conditions showed difference. The expression of PdFT in abortive flower buds was lower than that in normal bud. GA3 treatment and removing leaves could increase the expression of PdFT. The results of SDS-PAGE showed that the expressed protein in E. coli BL21 (DE3) was consistent with the size of expected.[Conclusion]The PdFT isolated from P. delavayi Franch. is highly homologous with the other FT genes isolated from other

  19. Molecular Control of Flowering in Response to Day Length in Rice (F)

    Institute of Scientific and Technical Information of China (English)

    Vittoria Brambilla; Fabio Fornara

    2013-01-01

    Flowering at the most appropriate times of the year requires careful monitoring of environmental conditions and correct integration of such information with an endogenous molecular network.Rice (Oryza sativa) is a facultative short day plant,and flowers quickly under short day lengths,as opposed to Arabidopsis thaliana whose flowering is accelerated by longer days.Despite these physiological differences,several genes controlling flowering in response to day length (or photoperiod) are conserved between rice and Arabidopsis,and the molecular mechanisms involved are similar.Inductive day lengths trigger expression of florigenic proteins in leaves that can move to the shoot apical meristem to induce reproductive development.As compared to Arabidopsis,rice also possesses unique factors that regulate expression of florigenic genes.Here,we discuss recent advances in understanding the molecular mechanisms involved in day length perception,production of florigenic signals,and molecular responses of the shoot apical meristem to florigenic proteins.

  20. 成花素FT的调控运输及生理功能的研究进展%Progresses on Regulation, Transportation and Physiological Function of Florigen Flowering Locus T

    Institute of Scientific and Technical Information of China (English)

    胡帅; 肖文君; 张骋; 王萍; 常洪平; 王育; 袁聪颖; 陆秀涛; 万捷

    2014-01-01

    开花作为植物从营养生长到生殖生长的转折点,受外界环境变化影响,对植物发育和繁殖有着至关重要的作用.成花素(flowering locus T FT)蛋白作为拟南芥开花信号核心分子,在开花调控中扮演重要角色.拟南芥叶片在感应外界温度光照等因素变化后,通过生理钟(constants,CO)等蛋白及部分Mico-RNA正负协调调控筛管伴胞中的FT基因表达,FT蛋白通过筛管从叶片运输到茎顶端分生组织后,与一个碱性亮氨酸拉链(basicleucine zipper,bZIP)蛋白FD结合调控茎顶端分生组织(shoot apical meristem,SAM)中的花组织形成相关基因表达,继而诱导开花.对近年来FT基因在叶片中的调控、FT蛋白的运输及其在顶端分生组织中的开花诱导机理进行综述,为进一步完善FT表达调控及功能研究提供参考.

  1. Photoperiodic control of sugar release during the floral transition: What is the role of sugars in the florigenic signal?

    Science.gov (United States)

    Ortiz-Marchena, M Isabel; Romero, José M; Valverde, Federico

    2015-01-01

    Florigen is a mobile signal released by the leaves that reaching the shoot apical meristem (SAM), changes its developmental program from vegetative to reproductive. The protein FLOWERING LOCUS T (FT) constitutes an important element of the florigen, but other components such as sugars, have been also proposed to be part of this signal. (1-5) We have studied the accumulation and composition of starch during the floral transition in Arabidopsis thaliana in order to understand the role of carbon mobilization in this process. In A. thaliana and Antirrhinum majus the gene coding for the Granule-Bound Starch Synthase (GBSS) is regulated by the circadian clock (6,7) while in the green alga Chlamydomonas reinhardtii the homolog gene CrGBSS is controlled by photoperiod and circadian signals. (8,9) In a recent paper(10) we described the role of the central photoperiodic factor CONSTANS (CO) in the regulation of GBSS expression in Arabidopsis. This regulation is in the basis of the change in the balance between starch and free sugars observed during the floral transition. We propose that this regulation may contribute to the florigenic signal and to the increase in sugar transport required during the flowering process.

  2. Factorial combinations of protein interactions generate a multiplicity of florigen activation complexes in wheat and barley.

    Science.gov (United States)

    Li, Chengxia; Lin, Huiqiong; Dubcovsky, Jorge

    2015-10-01

    The FLOWERING LOCUS T (FT) protein is a central component of a mobile flowering signal (florigen) that is transported from leaves to the shoot apical meristem (SAM). Two FT monomers and two DNA-binding bZIP transcription factors interact with a dimeric 14-3-3 protein bridge to form a hexameric protein complex. This complex, designated as the 'florigen activation complex' (FAC), plays a critical role in flowering. The wheat homologue of FT, designated FT1 (= VRN3), activates expression of VRN1 in the leaves and the SAM, promoting flowering under inductive long days. In this study, we show that FT1, other FT-like proteins, and different FD-like proteins, can interact with multiple wheat and barley 14-3-3 proteins. We also identify the critical amino acid residues in FT1 and FD-like proteins required for their interactions, and demonstrate that 14-3-3 proteins are necessary bridges to mediate the FT1-TaFDL2 interaction. Using in vivo bimolecular fluorescent complementation (BiFC) assays, we demonstrate that the interaction between FT1 and 14-3-3 occurs in the cytoplasm, and that this complex is then translocated to the nucleus, where it interacts with TaFDL2 to form a FAC. We also demonstrate that a FAC including FT1, TaFDL2 and Ta14-3-3C can bind to the VRN1 promoter in vitro. Finally, we show that relative transcript levels of FD-like and 14-3-3 genes vary among tissues and developmental stages. Since FD-like proteins determine the DNA specificity of the FACs, variation in FD-like gene expression can result in spatial and temporal modulation of the effects of mobile FT-like signals.

  3. A few aspects of the physiology of flowering in photoperiodic sensitive plants

    Directory of Open Access Journals (Sweden)

    E. G. Groenewald

    2003-09-01

    Full Text Available Three aspects of the physiology of flowering in photoperiodic sensitive plants are discussed. These are the florigen hypothesis, phytochrome and the time measurement mechanism of flowering and genetic-molecular studies involved in flowering. There is evidence that the hypothetical compound, florigen, occurs in plants, but it has never been characterised. There is a family of phytochromes discovered in plants and some of them are involved with the circadian clock and thus with the time measurement mechanism of flowering. The molecular networks that interact to control flowering are being elucidated, by means of genetic-molecular techniques although at an early stage. It has not yet been possible to pinpoint florigen by these methods, but the future looks promising.

  4. Research progress of photoperiod regulated genes on flowering time in rice.

    Science.gov (United States)

    Deyan, Kong; Shoujun, Chen; Liguo, Zhou; Huan, Gao; Lijun, Luo; Zaochang, Liu

    2016-06-20

    Rice flowering regulation is an extremely complex process, which is controlled by genetic factors and external environment. Photoperiodic regulatory pathway is pivotal to control flowering in rice, in which florigen genes Hd3a and RTF1 are at the core and they are regulated by upstream Hd1-dependent, Ehd1-dependent, as well as both Hd1- and Ehd1-independent pathways. The three pathways bring a variety of light signal information together to Hd3a and RTF1 for further integration, and then transmit the signals in the form of florigen to the downstream flowering related genes. In this review, we summarize the research progress of photoperiod regulated genes on flowering time in rice, including the photoreceptors and circadian rhythm genes, the florigens, its upstream, downstream and interacting genes. We hope to provide a reference for in-depth study of rice flowering regulation.

  5. Iron-dependent modifications of the flower transcriptome, proteome, metabolome, and hormonal content in an Arabidopsis ferritin mutant.

    Science.gov (United States)

    Sudre, Damien; Gutierrez-Carbonell, Elain; Lattanzio, Giuseppe; Rellán-Álvarez, Rubén; Gaymard, Frédéric; Wohlgemuth, Gert; Fiehn, Oliver; Alvarez-Fernández, Ana; Zamarreño, Angel M; Bacaicoa, Eva; Duy, Daniela; García-Mina, Jose-María; Abadía, Javier; Philippar, Katrin; López-Millán, Ana-Flor; Briat, Jean-François

    2013-07-01

    Iron homeostasis is an important process for flower development and plant fertility. The role of plastids in these processes has been shown to be essential. To document the relationships between plastid iron homeostasis and flower biology further, a global study (transcriptome, proteome, metabolome, and hormone analysis) was performed of Arabidopsis flowers from wild-type and triple atfer1-3-4 ferritin mutant plants grown under iron-sufficient or excess conditions. Some major modifications in specific functional categories were consistently observed at these three omic levels, although no significant overlaps of specific transcripts and proteins were detected. These modifications concerned redox reactions and oxidative stress, as well as amino acid and protein catabolism, this latter point being exemplified by an almost 10-fold increase in urea concentration of atfer1-3-4 flowers from plants grown under iron excess conditions. The mutant background caused alterations in Fe-haem redox proteins located in membranes and in hormone-responsive proteins. Specific effects of excess Fe in the mutant included further changes in these categories, supporting the idea that the mutant is facing a more intense Fe/redox stress than the wild type. The mutation and/or excess Fe had a strong impact at the membrane level, as denoted by the changes in the transporter and lipid metabolism categories. In spite of the large number of genes and proteins responsive to hormones found to be regulated in this study, changes in the hormonal balance were restricted to cytokinins, especially in the mutant plants grown under Fe excess conditions.

  6. OsFTIP1-Mediated Regulation of Florigen Transport in Rice Is Negatively Regulated by a Ubiquitin-like Domain Kinase OsUbDKγ4.

    Science.gov (United States)

    Song, Shiyong; Cheng, Ying; Liu, Lu; Wang, Yanwen; Bao, Shengjie; Zhou, Xuan; Teo, Zhi Wei Norman; Mao, Chuanzao; Gan, Yinbo; Yu, Hao

    2017-03-02

    Flowering time is a critical agronomic trait that determines successful seed production and adaptation of crop plants. Photoperiodic control of this process in flowering plants is mediated by the long-distance mobile signal called florigen partly encoded by FLOWERING LOCUS T (FT) in Arabidopsis and its orthologs in other plant species. Despite the progress in understanding FT transport in the dicot model Arabidopsis, the mechanisms of florigen transport in monocots, which provide most of the biomass in agriculture, are unknown. Here we show that rice FT-INTERACTING PROTEIN 1 (OsFTIP1), a member of the family of multiple C2 domain and transmembrane region proteins (MCTPs) and the closest ortholog of Arabidopsis FTIP1, is required for export of RICE FLOWERING LOCUS T 1 (RFT1) from companion cells to sieve elements. This affects RFT1 movement to the shoot apical meristem and its regulation of rice flowering time under long days. We further reveal that a ubiquitin-like domain kinase γ4, OsUbDKγ4, interacts with OsFTIP1, and modulates its degradation in leaves through the 26S proteasome, which in turn affects RFT1 transport to the SAM. Thus, dynamic modulation of OsFTIP1 abundance in leaves by a negative regulator OsUbDKγ4 is integral to the role of OsFTIP1 in mediating RFT1 transport in rice, and provide key evidence for a conserved role of FTIP1-like MCTPs in mediating florigen transport in flowering plants.

  7. Graft-transmissible action of Arabidopsis FLOWERING LOCUS T protein to promote flowering.

    Science.gov (United States)

    Notaguchi, Michitaka; Daimon, Yasufumi; Abe, Mitsutomo; Araki, Takashi

    2009-02-01

    Day length perceived by a leaf is a major environmental factor that controls the timing of flowering. It has been believed that a mobile, long-distance signal called florigen is produced in the leaf, and is transported to the shoot apex where it triggers floral morphogenesis. Grafting experiments have shown that florigen is transmissible from a donor plant that has been subjected to inductive day length to an un-induced recipient plant. However, the nature of florigen has long remained elusive. Recent studies have provided evidence that the FLOWERING LOCUS T (FT) protein in Arabidopsis and corresponding proteins in other species are an important part of florigen. Our work showed that the FT activity, either from overexpressing or inducible transgenes or from the endogenous gene, to promote flowering is transmissible through a graft junction, and that an FT protein with a T7 tag (FT-T7) is transported from a donor scion to the apical region of recipient stock plants and becomes detectable within a short period of 24-48 h. That the FT-green fluorescent protein (GFP) fusion protein (FT:GFP) retains limited ability for graft-transmissible action was confirmed.

  8. Florigen unmasked - exciting prospects for horticulture

    Science.gov (United States)

    The pioneer work of Garner and Allard, who coined the term “photoperiod” to describe the dramatic effects of day length on flowering of many plants, led to the widespread commercial use of photoperiod modification to control flowering in plants, particularly ornamentals. M.K. Chailakhyan suggested t...

  9. Suppressor of rid1 (SID1) shares common targets with RID1 on florigen genes to initiate floral transition in rice.

    Science.gov (United States)

    Deng, Li; Li, Lingmei; Zhang, Shuo; Shen, Jianqiang; Li, Shaobo; Hu, Sifan; Peng, Qiang; Xiao, Jinghua; Wu, Changyin

    2017-02-24

    The transition from vegetative to reproductive growth is a critical process in the life cycle of higher plants. Previously, we cloned Rice Indeterminate 1 (RID1), which acts as the master switch for the transition from the vegetative to reproductive phase in rice. Although the photoperiod pathway of RID1 inducing expression of the florigen genes Hd3a and RFT1 via Ehd1 has been established, the alternative pathways for the essential flowering transition need to be further examined. Here, we identified a Suppressor of rid1 (SID1), which rescues the never-flowering phenotype of rid1. SID1 encodes an INDETERMINATE DOMAIN (IDD) transcription factor. Mutation in SID1 showed the delayed flowering phenotype. Gain-of-function of SID1, OsIDD1, or OsIDD6 could restore the rid1 to flowering. Further analyses showed SID1 and RID1 directly target the promoter regions of Hd3a and RFT1, two florigen genes in rice. Taken together, our results reveal an autonomous flowering pathway might be mediated by RID1, thereby controlling the phase transition from vegetative to reproductive development in rice.

  10. Understanding the genetic and epigenetic architecture in complex network of rice flowering pathways.

    Science.gov (United States)

    Sun, Changhui; Chen, Dan; Fang, Jun; Wang, Pingrong; Deng, Xiaojian; Chu, Chengcai

    2014-12-01

    Although the molecular basis of flowering time control is well dissected in the long day (LD) plant Arabidopsis, it is still largely unknown in the short day (SD) plant rice. Rice flowering time (heading date) is an important agronomic trait for season adaption and grain yield, which is affected by both genetic and environmental factors. During the last decade, as the nature of florigen was identified, notable progress has been made on exploration how florigen gene expression is genetically controlled. In Arabidopsis expression of certain key flowering integrators such as FLOWERING LOCUS C (FLC) and FLOWERING LOCUS T (FT) are also epigenetically regulated by various chromatin modifications, however, very little is known in rice on this aspect until very recently. This review summarized the advances of both genetic networks and chromatin modifications in rice flowering time control, attempting to give a complete view of the genetic and epigenetic architecture in complex network of rice flowering pathways.

  11. Long-distance, graft-transmissible action of Arabidopsis FLOWERING LOCUS T protein to promote flowering.

    Science.gov (United States)

    Notaguchi, Michitaka; Abe, Mitsutomo; Kimura, Takahiro; Daimon, Yasufumi; Kobayashi, Toshinori; Yamaguchi, Ayako; Tomita, Yuki; Dohi, Koji; Mori, Masashi; Araki, Takashi

    2008-11-01

    Day length perceived by a leaf is a major environmental factor that controls the timing of flowering. It has been believed that a mobile, long-distance signal called florigen is produced in the leaf under inductive day length conditions, and is transported to the shoot apex where it triggers floral morphogenesis. Grafting experiments have shown that florigen is transmissible from a donor plant that has been subjected to inductive day length to an uninduced recipient plant. However, the nature of florigen has long remained elusive. Arabidopsis FLOWERING LOCUS T (FT) is expressed in cotyledons and leaves in response to inductive long days (LDs). FT protein, with a basic region/leucine zipper (bZIP) transcription factor FD, acts in the shoot apex to induce target meristem identity genes such as APETALA1 (AP1) and initiates floral morphogenesis. Recent studies have provided evidence that the FT protein in Arabidopsis and corresponding proteins in other species are an important part of florigen. Our work shows that the FT activity, either from overexpressing or inducible transgenes or from the endogenous gene, to promote flowering is transmissible through a graft junction, and that an FT protein with a T7 tag is transported from a donor scion to the apical region of recipient stock plants and becomes detectable within a day or two. The sequence and structure of mRNA are not of critical importance for the long-distance action of the FT gene. These observations led to the conclusion that the FT protein, but not mRNA, is the essential component of florigen.

  12. Florigen-Encoding Genes of Day-Neutral and Photoperiod-Sensitive Maize Are Regulated by Different Chromatin Modifications at the Floral Transition.

    Science.gov (United States)

    Mascheretti, Iride; Turner, Katie; Brivio, Roberta S; Hand, Andrew; Colasanti, Joseph; Rossi, Vincenzo

    2015-08-01

    The activity of the maize (Zea mays) florigen gene ZEA CENTRORADIALIS8 (ZCN8) is associated with the floral transition in both day-neutral temperate maize and short-day (SD)-requiring tropical maize. We analyzed transcription and chromatin modifications at the ZCN8 locus and its nearly identical paralog ZCN7 during the floral transition. This analysis was performed with day-neutral maize (Zea mays ssp. mays), where flowering is promoted almost exclusively via the autonomous pathway through the activity of the regulatory gene indeterminate1 (id1), and tropical teosinte (Zea mays ssp. parviglumis) under floral inductive and noninductive photoperiods. Comparison of ZCN7/ZCN8 histone modification profiles in immature leaves of nonflowering id1 mutants and teosinte grown under floral inhibitory photoperiods reveals that both id1 floral inductive activity and SD-mediated induction result in histone modification patterns that are compatible with the formation of transcriptionally competent chromatin environments. Specific histone modifications are maintained during leaf development and may represent a chromatin signature that favors the production of processed ZCN7/ZCN8 messenger RNA in florigen-producing mature leaf. However, whereas id1 function promotes histone H3 hyperacetylation, SD induction is associated with increased histone H3 dimethylation and trimethylation at lysine-4. In addition, id1 and SD differently affect the production of ZCN7/ZCN8 antisense transcript. These observations suggest that distinct mechanisms distinguish florigen regulation in response to autonomous and photoperiod pathways. Finally, the identical expression and histone modification profiles of ZCN7 and ZCN8 in response to floral induction suggest that ZCN7 may represent a second maize florigen.

  13. A pair of floral regulators sets critical day length for Hd3a florigen expression in rice.

    Science.gov (United States)

    Itoh, Hironori; Nonoue, Yasunori; Yano, Masahiro; Izawa, Takeshi

    2010-07-01

    The critical day length triggering photoperiodic flowering is set as an acute, accurate threshold in many short-day plants, including rice. Here, we show that, unlike the Arabidopsis florigen gene FT, the rice florigen gene Hd3a (Heading date 3a) is toggled by only a 30-min day-length reduction. Hd3a expression is induced by Ehd1 (Early heading date 1) expression when blue light coincides with the morning phase set by OsGIGANTEA(OsGI)-dependent circadian clocks. Ehd1 expression is repressed by both night breaks under short-day conditions and morning light signals under long-day conditions. Ghd7 (Grain number, plant height and heading date 7) was acutely induced when phytochrome signals coincided with a photosensitive phase set differently by distinct photoperiods and this induction repressed Ehd1 the next morning. Thus, two distinct gating mechanisms--of the floral promoter Ehd1 and the floral repressor Ghd7--could enable manipulation of slight differences in day length to control Hd3a transcription with a critical day-length threshold.

  14. My favourite flowering image: the role of cytokinin as a flowering signal.

    Science.gov (United States)

    Bernier, Georges

    2013-12-01

    My favourite flowering image shows a section in a shoot apical meristem of Sinapis alba undertaking the very first step of its transition to flowering. This step is the activation of the SaSOC1 gene, the Sinapis orthologue of Arabidopsis SUPPRESSOR OF OVEREXPRESSION OF CO1 (SOC1), in a few central cells of the meristem. Hidden behind this picture is my long quest of physiological signals controlling flowering. Milestones of this story are briefly recounted here and this gives me an opportunity to raise a number of questions about the nature and function of florigen.

  15. Calcium-dependent protein kinases responsible for the phosphorylation of a bZIP transcription factor FD crucial for the florigen complex formation.

    Science.gov (United States)

    Kawamoto, Nozomi; Sasabe, Michiko; Endo, Motomu; Machida, Yasunori; Araki, Takashi

    2015-02-09

    Appropriate timing of flowering is critical for reproductive success and necessarily involves complex genetic regulatory networks. A mobile floral signal, called florigen, is a key molecule in this process, and flowering locus T (FT) protein is its major component in Arabidopsis. FT is produced in leaves, but promotes the floral transition in the shoot apex, where it forms a complex with a basic region/leucine-zipper (bZIP) transcription factor, FD. Formation of the florigen complex depends on the supposed phosphorylation of FD; hitherto, however, the responsible protein kinase(s) have not been identified. In this study, we prepared protein extracts from shoot apices of plants around the floral transition, and detected a protein kinase activity that phosphorylates a threonine residue at position 282 of FD (FD T282), which is a crucial residue for the complex formation with FT via 14-3-3. The kinase activity was calcium-dependent. Subsequent biochemical, cellular, and genetic analyses showed that three calcium-dependent protein kinases (CDPKs) efficiently phosphorylate FD T282. Two of them (CPK6 and CPK33) are expressed in shoot apical meristem and directly interact with FD, suggesting they have redundant functions. The loss of function of one CDPK (CPK33) resulted in a weak but significant late-flowering phenotype.

  16. Phloem-mobile signals affecting flowers: applications for crop breeding.

    Science.gov (United States)

    McGarry, Roisin C; Kragler, Friedrich

    2013-04-01

    Transport of endogenous macromolecules within and between tissues serves as a signaling pathway to regulate numerous aspects of plant growth. The florigenic FT gene product moves via the phloem from leaves to apical tissues and induces the flowering program in meristems. Similarly, short interfering RNA (siRNA) signals produced in source or sink tissues move cell-to-cell and long distance via the phloem to apical tissues. Recent advances in identifying these mobile signals regulating flowering or the epigenetic status of targeted tissues can be applicable to crop-breeding programs. In this review, we address the identity of florigen, the mechanism of allocation, and how virus-induced flowering and grafting of transgenes producing siRNA signals affecting meiosis can produce transgene-free progenies useful for agriculture.

  17. Variations in Hormones and Antioxidant Status in Relation to Flowering in Early, Mid, and Late Varieties of Date Palm (Phoenix dactylifera of United Arab Emirates

    Directory of Open Access Journals (Sweden)

    Abdul J. Cheruth

    2015-01-01

    Full Text Available The present study was carried out to assess the status of various hormones responsible for the flower induction of Nagal, Lulu, and Khalas date palm varieties in UAE. The nonenzymatic antioxidant compounds and the antioxidant enzymatic activities at preflowering, flowering, and postflowering stages of the date palm varieties were quantified. The ABA and zeatin concentrations were found to be significantly higher during the preflowering stage but gradually decreased during the flowering period and then increased after the flowering stage. Gibberellic acid (GA concentrations were significantly higher in the early flowering varieties and higher levels of ABA may contribute to the delayed flowering in mid and late varieties. The results on hormone profiling displayed a significant variation between seasons (preflowering, flowering, and postflowering and also between the three date palms (early, mid, and late flowering varieties. Ascorbic acid (AA concentration was low at the preflowering stage in the early flowering Nagal (0.694 mg/g dw, which is similar with the late flowering Lulu variety (0.862 mg/g dw. However, Khalas variety showed significantly higher amount of AA content (7.494 mg/g dw at the preflowering stage when compared to other varieties. In flowering stage, Nagal (0.814 mg/g dw and Lulu (0.963 mg/g dw were similar with respect to the production of AA, while the mid flowering variety showed significantly higher amount of AA (9.358 mg/g dw. The Khalas variety produced the highest tocopherol at 4.78 mg/g dw compared to Nagal and Lulu, at 1.997 and 1.908 mg/g dw, respectively, during the preflowering stage. In Nagal variety, the content of reduced glutathione (GSH at the preflowering stage was 0.507 mg/g dw, which was not significantly different from the flowering and postflowering stages at 0.4 and 0.45 mg/g dw, respectively. The GSH was significantly higher in Khalas compared to Nagal and Lulu

  18. Effect of exogenous GA3 and its inhibitor paclobutrazol on floral formation, endogenous hormones, and flowering-associated genes in 'Fuji' apple (Malus domestica Borkh.).

    Science.gov (United States)

    Zhang, Songwen; Zhang, Dong; Fan, Sheng; Du, Lisha; Shen, Yawen; Xing, Libo; Li, Youmei; Ma, Juanjuan; Han, Mingyu

    2016-10-01

    Gibberellins (GAs) reduce apple (Malus domestica) flowering rates; however, the mechanism of their action is not fully understood. To gain a better insight into gibberellin-regulated flowering, here, 5 year-old 'Fuji' apple trees were used to explore the responses of hormones [GA1+3, GA4+7, indole-3-acetic acid (IAA), zeatin-riboside (ZR), and abscisic acid (ABA)], and gibberellin- and flowering-associated genes, to applications of gibberellin acid (GA3) and paclobutrazol (PAC). Results showed that GA3 relatively stimulated vegetative growth and delayed floral induction. Moreover, GA3 spraying significantly affected contents of all endogenous hormones and all the genes tested in at least one time points: the content of endogenous GAs was increased instantly and that of ZR was reduced at 44 days after fullbloom (DAF), which might constitute an unfavorable factor for flower formation; MdKO (ent-kaurene oxidase gene) and MdGA20ox (GA20 oxidase gene) were significantly repressed by a high level of GAs through the negative feedback regulation of GA; additionally, the MdSPLs (SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE) in this study were all significantly repressed by GA3 but promoted by PAC; the expression of MdFT1/2 (FLOWERING LOCUS T), MdSOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1) and MdAP1 (APETALA1) in GA3-treated buds changed in the same way, and they were repressed at 44 DAF. We suppose that GA3 spraying disrupts the balance between ZR and GAs, and inhibits floral induction, probably by suppressing MdSPLs and the floral integrators in flower induction, which ultimately contributed to inhibiting flower formation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. 水稻成花素Hd3a及其受体分子机制研究进展%Research on Molecular Mechanismof Hd3a Florigen and Hd3a Receptor in Rice

    Institute of Scientific and Technical Information of China (English)

    祁军; 顾超; 东锐; 张坤; 崔百明; 黄先忠

    2012-01-01

    成花素是有一个控制开花位点的基因FT( FLOWERING LOCUS T)编码的产物,成花素FT是植物开花途径中的关键整合因子.而水稻中的Hd3a( HEADING DATE 3a)是拟南芥FT的同源基因,Hd3a蛋白即是水稻中的成花激素,其在叶片中表达并通过微管组织运输到顶端分生组织,同成花素受体14-3-3蛋白结合,然后又附着到另一种转录因子OsFD1( FLOWERING LOCUS D)上形成成花素激活复合体,使开花基因OsMADS15功能活跃起来.文中对水稻成花素Hd3a及其受体14-3-3蛋白分子作用机制的研究进展进行了综述,为进一步研究植物开花分子生物学提供参考.%Florigen is encoded by FT (FLOWERING LOCUS T) , which is a critical integrator of flowering signals pathway. Hd3a (HEADING DATE 3a) is a homologue of FT in rice, which is responsible for rice florigen. Hd3a protein translated in leaf is transported to the apical cells of shoots through vascular tissue, interacts with 14-3-3 protein acting as intracellular receptors, then binds to another transcription factor OsFDl (FLOWERING LOCUS Dl). The resultant ternary florigen activation complex activates transcription of 0sMADS\\5 which leads to flowering. This article reviewed the recent progress on the molecular mechanism of rice Hd3a florigen and its intracellular receptors 14-3-3 protein, providing valuable information for further research of flowering molecular biology in plants.

  20. Flowering and tuberization: a tale of two nightshades.

    Science.gov (United States)

    Abelenda, José A; Navarro, Cristina; Prat, Salomé

    2014-02-01

    The concept of florigen, postulated in the early 1930s, has taken form after the identification of the FLOWERING LOCUS T (FT) protein as the flowering-inducing signal. Besides their role in flowering, FT genes were subsequently reported to play additional functions in other biological processes. This is particularly relevant in the nightshades, where the FT genes appear to have undergone considerable expansion at the functional level and gained a new role in the control of storage organ formation in potato (Solanum tuberosum). Neofunctionalization of FT homologs in the nightshades identifies these proteins as a new class of primary signaling components that modulate development and organogenesis in these agronomic relevant species.

  1. PHYTOCHROME C is an essential light receptor for photoperiodic flowering in the temperate grass, Brachypodium distachyon.

    Science.gov (United States)

    Woods, Daniel P; Ream, Thomas S; Minevich, Gregory; Hobert, Oliver; Amasino, Richard M

    2014-09-01

    We show that in the temperate grass, Brachypodium distachyon, PHYTOCHROME C (PHYC), is necessary for photoperiodic flowering. In loss-of-function phyC mutants, flowering is extremely delayed in inductive photoperiods. PHYC was identified as the causative locus by utilizing a mapping by sequencing pipeline (Cloudmap) optimized for identification of induced mutations in Brachypodium. In phyC mutants the expression of Brachypodium homologs of key flowering time genes in the photoperiod pathway such as GIGANTEA (GI), PHOTOPERIOD 1 (PPD1/PRR37), CONSTANS (CO), and florigen/FT are greatly attenuated. PHYC also controls the day-length dependence of leaf size as the effect of day length on leaf size is abolished in phyC mutants. The control of genes upstream of florigen production by PHYC was likely to have been a key feature of the evolution of a long-day flowering response in temperate pooid grasses.

  2. Change of Endogenous Hormones, Amino-acid and Nutrition in Flowering Stage of Phyllostachys praecox f. prevernalis%雷竹开花期内源激素、氨基酸和营养成分含量变化

    Institute of Scientific and Technical Information of China (English)

    何奇江; 汪奎宏; 华锡奇; 童晓青

    2005-01-01

    The test site was located in Jincheng Town, Lin'an City, Zhejiang Province. The leaves, culms and rhizomes of two-year-old and three-year-old flowering individuals or non-flowering individuals were taken from the same bamboo (Phyllostachys praecox f. prevernalis ) forest. The culms and rhizomes of one-year-old flowering or non-flowering were also taken from the same bamboo forest. Based on analysis of the content of endogenous hormones, amino-acid and nutrition in flowering stage of bamboo, the results showed that abscisic acid(ABA) had main effect on accelerating its flowering and the increase of cytokinin(CTK) was also one reason for bringing flower, but indole-3-acetic acid(IAA) antagonized on its flowering. Total aminoacid in the non-flowering bamboo was 23.01 % higher than that in flowering bamboo. Aspartic acid (ASP) could delay flowering. Protein, especially protein in leaves had main effect on senescence procedure. Increase of phosphorus content in flowering bamboo could accelerate metabolizing, and therefore promote senescence of bamboo.

  3. Genetic engineering of novel flower colors in floricultural plants: recent advances via transgenic approaches.

    Science.gov (United States)

    Nishihara, Masahiro; Nakatsuka, Takashi

    2010-01-01

    Since the first successful genetic engineering of flower color in petunia, several new techniques have been developed and applied to modify flower color not only in model plants but also in floricultural plants. A typical example is the commercial violet-flowered carnation "Moondust series" developed by Suntry Ltd. and Florigene Ltd. More recently, blue-flowered roses have been successfully produced and are expected to be commercially available in the near future. In recent years, successful modification of flower color by sophisticated regulation of flower-pigment metabolic pathways has become possible. In this chapter, we review recent advances in flower color modification by genetic engineering, especially focusing on the methodology. We have included our own recent results on successful production of flower-color-modified transgenic plants in a model plant, tobacco and an ornamental plant, gentian. Based on these results, genetic engineering of flower color for improvement of floricultural plants is discussed.

  4. BRANCHED1 interacts with FLOWERING LOCUS T to repress the floral transition of the axillary meristems in Arabidopsis.

    Science.gov (United States)

    Niwa, Masaki; Daimon, Yasufumi; Kurotani, Ken-ichi; Higo, Asuka; Pruneda-Paz, José L; Breton, Ghislain; Mitsuda, Nobutaka; Kay, Steve A; Ohme-Takagi, Masaru; Endo, Motomu; Araki, Takashi

    2013-04-01

    Plant architecture shows a large degree of developmental plasticity. Some of the key determinants are the timing of the floral transition induced by a systemic flowering signal (florigen) and the branching pattern regulated by key factors such as BRANCHED1 (BRC1). Here, we report that BRC1 interacts with the florigen proteins FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF) but not with TERMINAL FLOWER1, a floral repressor. FT protein induced in leaves moves into the subtended bud, suggesting that FT protein also plays a role in promotion of the floral transition in the axillary meristem (AM). The brc1-2 mutant shows an earlier floral transition in the axillary shoots compared with the wild type, suggesting that BRC1 plays a role in delaying the floral transition of the AMs. Genetic and gene expression analyses suggest that BRC1 interferes with florigen (FT and TSF) function in the AMs. Consistent with this, BRC1 ectopically expressed in the shoot apical meristem delays the floral transition in the main shoot. These results taken together suggest that BRC1 protein interacts with FT and TSF proteins and modulates florigen activity in the axillary buds to prevent premature floral transition of the AMs.

  5. Natural variation of the RICE FLOWERING LOCUS T 1 contributes to flowering time divergence in rice.

    Directory of Open Access Journals (Sweden)

    Eri Ogiso-Tanaka

    Full Text Available In rice (Oryza sativa L., there is a diversity in flowering time that is strictly genetically regulated. Some indica cultivars show extremely late flowering under long-day conditions, but little is known about the gene(s involved. Here, we demonstrate that functional defects in the florigen gene RFT1 are the main cause of late flowering in an indica cultivar, Nona Bokra. Mapping and complementation studies revealed that sequence polymorphisms in the RFT1 regulatory and coding regions are likely to cause late flowering under long-day conditions. We detected polymorphisms in the promoter region that lead to reduced expression levels of RFT1. We also identified an amino acid substitution (E105K that leads to a functional defect in Nona Bokra RFT1. Sequencing of the RFT1 region in rice accessions from a global collection showed that the E105K mutation is found only in indica, and indicated a strong association between the RFT1 haplotype and extremely late flowering in a functional Hd1 background. Furthermore, SNPs in the regulatory region of RFT1 and the E105K substitution in 1,397 accessions show strong linkage disequilibrium with a flowering time-associated SNP. Although the defective E105K allele of RFT1 (but not of another florigen gene, Hd3a is found in many cultivars, relative rate tests revealed no evidence for differential rate of evolution of these genes. The ratios of nonsynonymous to synonymous substitutions suggest that the E105K mutation resulting in the defect in RFT1 occurred relatively recently. These findings indicate that natural mutations in RFT1 provide flowering time divergence under long-day conditions.

  6. ABA-dependent control of GIGANTEA signalling enables drought escape via up-regulation of FLOWERING LOCUS T in Arabidopsis thaliana.

    Science.gov (United States)

    Riboni, Matteo; Robustelli Test, Alice; Galbiati, Massimo; Tonelli, Chiara; Conti, Lucio

    2016-12-01

    One strategy deployed by plants to endure water scarcity is to accelerate the transition to flowering adaptively via the drought escape (DE) response. In Arabidopsis thaliana, activation of the DE response requires the photoperiodic response gene GIGANTEA (GI) and the florigen genes FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF). The phytohormone abscisic acid (ABA) is also required for the DE response, by promoting the transcriptional up-regulation of the florigen genes. The mode of interaction between ABA and the photoperiodic genes remains obscure. In this work we use a genetic approach to demonstrate that ABA modulates GI signalling and consequently its ability to activate the florigen genes. We also reveal that the ABA-dependent activation of FT, but not TSF, requires CONSTANS (CO) and that impairing ABA signalling dramatically reduces the expression of florigen genes with little effect on the CO transcript profile. ABA signalling thus has an impact on the core genes of photoperiodic signalling GI and CO by modulating their downstream function and/or activities rather than their transcript accumulation. In addition, we show that as well as promoting flowering, ABA simultaneously represses flowering, independent of the florigen genes. Genetic analysis indicates that the target of the repressive function of ABA is the flowering-promoting gene SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1), a transcription factor integrating floral cues in the shoot meristem. Our study suggests that variations in ABA signalling provide different developmental information that allows plants to co-ordinate the onset of the reproductive phase according to the available water resources.

  7. Hormones

    Science.gov (United States)

    Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work ... glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, ...

  8. Photoperiodic flowering: time measurement mechanisms in leaves.

    Science.gov (United States)

    Song, Young Hun; Shim, Jae Sung; Kinmonth-Schultz, Hannah A; Imaizumi, Takato

    2015-01-01

    Many plants use information about changing day length (photoperiod) to align their flowering time with seasonal changes to increase reproductive success. A mechanism for photoperiodic time measurement is present in leaves, and the day-length-specific induction of the FLOWERING LOCUS T (FT) gene, which encodes florigen, is a major final output of the pathway. Here, we summarize the current understanding of the molecular mechanisms by which photoperiodic information is perceived in order to trigger FT expression in Arabidopsis as well as in the primary cereals wheat, barley, and rice. In these plants, the differences in photoperiod are measured by interactions between circadian-clock-regulated components, such as CONSTANS (CO), and light signaling. The interactions happen under certain day-length conditions, as previously predicted by the external coincidence model. In these plants, the coincidence mechanisms are governed by multilayered regulation with numerous conserved as well as unique regulatory components, highlighting the breadth of photoperiodic regulation across plant species.

  9. FE, a phloem-specific Myb-related protein, promotes flowering through transcriptional activation of FLOWERING LOCUS T and FLOWERING LOCUS T INTERACTING PROTEIN 1.

    Science.gov (United States)

    Abe, Mitsutomo; Kaya, Hidetaka; Watanabe-Taneda, Ayako; Shibuta, Mio; Yamaguchi, Ayako; Sakamoto, Tomoaki; Kurata, Tetsuya; Ausín, Israel; Araki, Takashi; Alonso-Blanco, Carlos

    2015-09-01

    In many flowering plants, the transition to flowering is primarily affected by seasonal changes in day length (photoperiod). An inductive photoperiod promotes flowering via synthesis of a floral stimulus, called florigen. In Arabidopsis thaliana, the FLOWERING LOCUS T (FT) protein is an essential component of florigen, which is synthesized in leaf phloem companion cells and is transported through phloem tissue to the shoot apical meristem where floral morphogenesis is initiated. However, the molecular mechanism involved in the long-distance transport of FT protein remains elusive. In this study, we characterized the classic Arabidopsis mutant fe, which is involved in the photoperiodic induction of flowering, and showed that FE encodes a phloem-specific Myb-related protein that was previously reported as ALTERED PHLOEM DEVELOPMENT. Phenotypic analyses of the fe mutant showed that FT expression is reduced in leaf phloem companion cells. In addition, the transport of FT protein from leaves to the shoot apex is impaired in the fe mutant. Expression analyses further demonstrated that FE is also required for transcriptional activation of FLOWERING LOCUS T INTERACTING PROTEIN 1 (FTIP1), an essential regulator for selective trafficking of the FT protein from companion cells to sieve elements. These findings indicate that FE plays a dual role in the photoperiodic induction of flowering: as a transcriptional activator of FT on the one hand, and its transport machinery component, FTIP1, on the other hand. Thus, FE is likely to play a role in regulating FT by coordinating FT synthesis and FT transport in phloem companion cells.

  10. GmFT2a and GmFT5a Redundantly and Differentially Regulate Flowering through Interaction with and Upregulation of the bZIP Transcription Factor GmFDL19 in Soybean

    OpenAIRE

    2014-01-01

    FLOWERING LOCUS T (FT) is the key flowering integrator in Arabidopsis (Arabidopsis thaliana), and its homologs encode florigens in many plant species regardless of their photoperiodic response. Two FT homologs, GmFT2a and GmFT5a, are involved in photoperiod-regulated flowering and coordinately control flowering in soybean. However, the molecular and genetic understanding of the roles played by GmFT2a and GmFT5a in photoperiod-regulated flowering in soybean is very limited. In this study, we d...

  11. Environmental stress and flowering time: the photoperiodic connection.

    Science.gov (United States)

    Riboni, Matteo; Robustelli Test, Alice; Galbiati, Massimo; Tonelli, Chiara; Conti, Lucio

    2014-01-01

    Plants maximize their chances to survive adversities by reprogramming their development according to environmental conditions. Adaptive variations in the timing to flowering reflect the need for plants to set seeds under the most favorable conditions. A complex network of genetic pathways allows plants to detect and integrate external (e.g., photoperiod and temperature) and/or internal (e.g., age) information to initiate the floral transition. Furthermore different types of environmental stresses play an important role in the floral transition. The emerging picture is that stress conditions often affect flowering through modulation of the photoperiodic pathway. In this review we will discuss different modes of cross talk between stress signaling and photoperiodic flowering, highlighting the central role of the florigen genes in this process.

  12. Flowering time regulation: photoperiod- and temperature-sensing in leaves.

    Science.gov (United States)

    Song, Young Hun; Ito, Shogo; Imaizumi, Takato

    2013-10-01

    Plants monitor changes in photoperiod and temperature to synchronize their flowering with seasonal changes to maximize fitness. In the Arabidopsis photoperiodic flowering pathway, the circadian clock-regulated components, such as FLAVIN-BINDING, KELCH REPEAT, F-BOX 1 and CONSTANS, both of which have light-controlled functions, are crucial to induce the day-length specific expression of the FLOWERING LOCUS T (FT) gene in leaves. Recent advances indicate that FT transcriptional regulation is central for integrating the information derived from other important internal and external factors, such as developmental age, amount of gibberellic acid, and the ambient temperature. In this review, we describe how these factors interactively regulate the expression of FT, the main component of florigen, in leaves.

  13. Recent Advances of Flowering Locus T Gene in Higher Plants

    OpenAIRE

    Shuiyuan Cheng; Feng Xu; Xiaofeng Rong; Xiaohua Huang

    2012-01-01

    Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone and can induce flowering by long-distance transportation. In the present study, many FT-like genes were isolated, and the transgenic results show that FT gene can promote flowering in plants. This paper reviews the progress of t...

  14. A MYB-domain protein EFM mediates flowering responses to environmental cues in Arabidopsis.

    Science.gov (United States)

    Yan, Yuanyuan; Shen, Lisha; Chen, Ying; Bao, Shengjie; Thong, Zhonghui; Yu, Hao

    2014-08-25

    Plants adjust the timing of the transition to flowering to ensure their reproductive success in changing environments. Temperature and light are major environmental signals that affect flowering time through converging on the transcriptional regulation of FLOWERING LOCUS T (FT) encoding the florigen in Arabidopsis. Here, we show that a MYB transcription factor EARLY FLOWERING MYB PROTEIN (EFM) plays an important role in directly repressing FT expression in the leaf vasculature. EFM mediates the effect of ambient temperature on flowering and is directly promoted by another major FT repressor, SHORT VEGETATIVE PHASE. EFM interacts with an H3K36me2 demethylase JMJ30, which forms a negative feedback regulatory loop with the light-responsive circadian clock, to specifically demethylate an active mark H3K36me2 at FT. Our results suggest that EFM is an important convergence point that mediates plant responses to temperature and light to determine the timing of reproduction.

  15. Monopodial and sympodial branching architecture in cotton is differentially regulated by the Gossypium hirsutum SINGLE FLOWER TRUSS and SELF-PRUNING orthologs.

    Science.gov (United States)

    McGarry, Roisin C; Prewitt, Sarah F; Culpepper, Samantha; Eshed, Yuval; Lifschitz, Eliezer; Ayre, Brian G

    2016-10-01

    Domestication of upland cotton (Gossypium hirsutum) converted it from a lanky photoperiodic perennial to a day-neutral annual row-crop. Residual perennial traits, however, complicate irrigation and crop management, and more determinate architectures are desired. Cotton simultaneously maintains robust monopodial indeterminate shoots and sympodial determinate shoots. We questioned if and how the FLOWERING LOCUS T/SINGLE FLOWER TRUSS (SFT)-like and TERMINAL FLOWER1/SELF-PRUNING (SP)-like genes control the balance of monopodial and sympodial growth in a woody perennial with complex growth habit. Virus-based manipulation of GhSP and GhSFT expression enabled unprecedented functional analysis of cotton development. GhSP maintains growth in all apices; in its absence, both monopodial and sympodial branch systems terminate precociously. GhSFT encodes a florigenic signal stimulating rapid onset of sympodial branching and flowering in side shoots of wild photoperiodic and modern day-neutral accessions. High florigen concentrations did not alter monopodial apices, implying that once a cotton apex is SP-determined, it cannot be reset by florigen. GhSP is also essential to establish and maintain cambial activity. Dynamic changes in GhSFT and GhSP levels navigate meristems between monopodial and sympodial programs in a single plant. SFT and SP influenced cotton domestication and are ideal targets for further agricultural optimization.

  16. 南瓜花发育过程中内源激素和多胺含量变化研究%Content changes of endogenous hormones and polyamine during flower development in pumpkin

    Institute of Scientific and Technical Information of China (English)

    杨贵先; 杨晓霞; 王洋洋; 徐文龙; 崔崇士; 屈淑平

    2016-01-01

    The female and male flowers in different development stages of subgynoecious pumpkin lines ‘2013‐12’ and monoecious lines‘9‐6’ were used as materials to test the content changes of five internal hormones and four polyamines .The results show that zeatin (ZT) content gradually reduces in male and female flowers along with the development of flower bud ,the ZT content in male flowers is higher than that in female flowers .IAA content in male flowers decreases firstly and then increases ,but IAA content in female flowers increases firstly and then decreases .Gibberellic acid (GA3 ) in the development of male and female flow‐ers shows a trend of gradual decline .Abscisic acid (ABA) content in male flowers shows the change trend of rise and decline ,the dynamics of ABA contents in the female flower buds show the change of rise ,decline and rise .Ethylene content gradually increa‐ses in female and female along with the development of flower bud ,and it is higher than that in female flowers .Spermidine (Spd) content is the highest ,followed by spermine (Spm) ,putrescine (Put) the lowest in the male and female flowers ,Spm and Spd content in male flowers along with flower development period always lower level ,Spm and Spd content in female flowers are high‐er than those in male flowers .%以南瓜强雌品系‘2013‐12’和强雄品系‘9‐6’为试材,研究南瓜雌、雄花发育过程中内源激素和多胺的变化。结果表明,玉米素(zeatin ,ZT)随南瓜雌雄花的发育逐渐降低,且雄花中ZT的含量高于雌花;南瓜雄花中生长素(IAA)含量呈现先上升、后下降的变化趋势,雌花中IAA含量呈现先下降、后上升的变化趋势;南瓜雌雄花发育过程中赤霉素(gibberellic acid ,GA3)均呈现逐渐下降的趋势;雄花脱落酸(abscisic acid ,ABA )含量呈现升-降的变化趋势,雌花ABA含量呈现升-降-升的规律;乙烯在南瓜花发育过程中

  17. The Oryza sativa Regulator HDR1 Associates with the Kinase OsK4 to Control Photoperiodic Flowering.

    Directory of Open Access Journals (Sweden)

    Xuehui Sun

    2016-03-01

    Full Text Available Rice is a facultative short-day plant (SDP, and the regulatory pathways for flowering time are conserved, but functionally modified, in Arabidopsis and rice. Heading date 1 (Hd1, an ortholog of Arabidopsis CONSTANS (CO, is a key regulator that suppresses flowering under long-day conditions (LDs, but promotes flowering under short-day conditions (SDs by influencing the expression of the florigen gene Heading date 3a (Hd3a. Another key regulator, Early heading date 1 (Ehd1, is an evolutionarily unique gene with no orthologs in Arabidopsis, which acts as a flowering activator under both SD and LD by promoting the rice florigen genes Hd3a and RICE FLOWERING LOCUST 1 (RFT1. Here, we report the isolation and characterization of the flowering regulator Heading Date Repressor1 (HDR1 in rice. The hdr1 mutant exhibits an early flowering phenotype under natural LD in a paddy field in Beijing, China (39°54'N, 116°23'E, as well as under LD but not SD in a growth chamber, indicating that HDR1 may functionally regulate flowering time via the photoperiod-dependent pathway. HDR1 encodes a nuclear protein that is most active in leaves and floral organs and exhibits a typical diurnal expression pattern. We determined that HDR1 is a novel suppressor of flowering that upregulates Hd1 and downregulates Ehd1, leading to the downregulation of Hd3a and RFT1 under LDs. We have further identified an HDR1-interacting kinase, OsK4, another suppressor of rice flowering under LDs. OsK4 acts similarly to HDR1, suppressing flowering by upregulating Hd1 and downregulating Ehd1 under LDs, and OsK4 can phosphorylate HD1 with HDR1 presents. These results collectively reveal the transcriptional regulators of Hd1 for the day-length-dependent control of flowering time in rice.

  18. The Oryza sativa Regulator HDR1 Associates with the Kinase OsK4 to Control Photoperiodic Flowering.

    Science.gov (United States)

    Sun, Xuehui; Zhang, Zhiguo; Wu, Jinxia; Cui, Xuean; Feng, Dan; Wang, Kai; Xu, Ming; Zhou, Li; Han, Xiao; Gu, Xiaofeng; Lu, Tiegang

    2016-03-01

    Rice is a facultative short-day plant (SDP), and the regulatory pathways for flowering time are conserved, but functionally modified, in Arabidopsis and rice. Heading date 1 (Hd1), an ortholog of Arabidopsis CONSTANS (CO), is a key regulator that suppresses flowering under long-day conditions (LDs), but promotes flowering under short-day conditions (SDs) by influencing the expression of the florigen gene Heading date 3a (Hd3a). Another key regulator, Early heading date 1 (Ehd1), is an evolutionarily unique gene with no orthologs in Arabidopsis, which acts as a flowering activator under both SD and LD by promoting the rice florigen genes Hd3a and RICE FLOWERING LOCUST 1 (RFT1). Here, we report the isolation and characterization of the flowering regulator Heading Date Repressor1 (HDR1) in rice. The hdr1 mutant exhibits an early flowering phenotype under natural LD in a paddy field in Beijing, China (39°54'N, 116°23'E), as well as under LD but not SD in a growth chamber, indicating that HDR1 may functionally regulate flowering time via the photoperiod-dependent pathway. HDR1 encodes a nuclear protein that is most active in leaves and floral organs and exhibits a typical diurnal expression pattern. We determined that HDR1 is a novel suppressor of flowering that upregulates Hd1 and downregulates Ehd1, leading to the downregulation of Hd3a and RFT1 under LDs. We have further identified an HDR1-interacting kinase, OsK4, another suppressor of rice flowering under LDs. OsK4 acts similarly to HDR1, suppressing flowering by upregulating Hd1 and downregulating Ehd1 under LDs, and OsK4 can phosphorylate HD1 with HDR1 presents. These results collectively reveal the transcriptional regulators of Hd1 for the day-length-dependent control of flowering time in rice.

  19. Flower Development

    OpenAIRE

    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.; Piñeyro-Nelson, Alma; Sánchez-Corrales, Yara E.

    2010-01-01

    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 ke...

  20. Florescimento em cana-de-açúcar Flowering in sugarcane

    Directory of Open Access Journals (Sweden)

    Rosilaine Araldi

    2010-03-01

    Full Text Available O florescimento da cana-de-açúcar é um processo fisiológico complexo formado por vários estádios de desenvolvimento, e cada estádio tem a sua própria necessidade ambiental e fisiológica. Os fatores externos relacionados com o florescimento são: fotoperíodo, temperatura, umidade e radiação solar, além da fertilidade do solo. Por outro lado, os fatores internos envolvem fitocromo, hormônios, florígeno, ácidos nucleicos, dentre outros. A intensidade do processo de florescimento e as consequências na qualidade da cana-de-açúcar variam com a variedade e com o clima. A redução do volume de caldo é o principal fator no qual o florescimento interfere, resultante do aumento do teor de fibras. Como as demais Poaceae, a cana-de-açúcar floresce, frutifica e morre, garantindo a perpetuação da espécie. Dessa forma, o homem procura interferir na natureza tentando evitar o florescimento da cana-de-açúcar, seja por meio de melhoramento genético ou por meio de reguladores vegetais. Em áreas comerciais de produção de cana-de-açúcar, onde há condições ideais para o florescimento da cultura, é recomendado o uso de variedade com potencial menos florífero. E, quando não é possível esse manejo varietal, o uso de inibidores do florescimento é a melhor alternativa para evitar mais perdas no conteúdo de sacarose.The sugarcane flowering is a complex physiological process that consists of several stages of development, each stage has its physiological and environmental requisition. The external factors related to flowering are: photoperiod, temperature, humidity, solar radiation in addition to soil fertility. Already the internal factors involved are: phytochrome, hormones, florigene, nucleic acids, among others. The intensity of the flowering and the consequences on the quality of sugarcane vary with the variety and the climate. The reduction of the sugarcane juice is the main factor which affected by the flowering, resulting

  1. Molecular dissection of the roles of phytochrome in photoperiodic flowering in rice.

    Science.gov (United States)

    Osugi, Asami; Itoh, Hironori; Ikeda-Kawakatsu, Kyoko; Takano, Makoto; Izawa, Takeshi

    2011-11-01

    Phytochromes mediate the photoperiodic control of flowering in rice (Oryza sativa), a short-day plant. Recent molecular genetics studies have revealed a genetic network that enables the critical daylength response of florigen gene expression. Analyses using a rice phytochrome chromophore-deficient mutant, photoperiod sensitivity5, have so far revealed that within this network, phytochromes are required for expression of Grain number, plant height and heading date7 (Ghd7), a floral repressor gene in rice. There are three phytochrome genes in rice, but the roles of each phytochrome family member in daylength response have not previously been defined. Here, we revealed multiple action points for each phytochrome in the critical daylength response of florigen expression by using single and double phytochrome mutant lines of rice. Our results show that either phyA alone or a genetic combination of phyB and phyC can induce Ghd7 mRNA, whereas phyB alone causes some reduction in levels of Ghd7 mRNA. Moreover, phyB and phyA can affect Ghd7 activity and Early heading date1 (a floral inducer) activity in the network, respectively. Therefore, each phytochrome gene of rice has distinct roles, and all of the phytochrome actions coordinately control the critical daylength response of florigen expression in rice.

  2. GmFT2a, a soybean homolog of FLOWERING LOCUS T, is involved in flowering transition and maintenance.

    Directory of Open Access Journals (Sweden)

    Hongbo Sun

    Full Text Available BACKGROUND: Flowering reversion can be induced in soybean (Glycine max L. Merr., a typical short-day (SD dicot, by switching from SD to long-day (LD photoperiods. This process may involve florigen, putatively encoded by FLOWERING LOCUS T (FT in Arabidopsis thaliana. However, little is known about the potential function of soybean FT homologs in flowering reversion. METHODS: A photoperiod-responsive FT homologue GmFT (renamed as GmFT2a hereafter was cloned from the photoperiod-sensitive cultivar Zigongdongdou. GmFT2a gene expression under different photoperiods was analyzed by real-time quantitative PCR. In situ hybridization showed direct evidence for its expression during flowering-related processes. GmFT2a was shown to promote flowering using transgenic studies in Arabidopsis and soybean. The effects of photoperiod and temperature on GmFT2a expression were also analyzed in two cultivars with different photoperiod-sensitivities. RESULTS: GmFT2a expression is regulated by photoperiod. Analyses of GmFT2a transcripts revealed a strong correlation between GmFT2a expression and flowering maintenance. GmFT2a transcripts were observed continuously within the vascular tissue up to the shoot apex during flowering. By contrast, transcripts decreased to undetectable levels during flowering reversion. In grafting experiments, the early-flowering, photoperiod-insensitive stock Heihe27 promotes the appearance of GmFT2a transcripts in the shoot apex of scion Zigongdongdou under noninductive LD conditions. The photothermal effects of GmFT2a expression diversity in cultivars with different photoperiod-sensitivities and a hypothesis is proposed. CONCLUSION: GmFT2a expression is associated with flowering induction and maintenance. Therefore, GmFT2a is a potential target gene for soybean breeding, with the aim of increasing geographic adaptation of this crop.

  3. Delay of Iris flower senescence by cytokinins and jasmonates

    NARCIS (Netherlands)

    Doorn, van W.G.; Celikel, F.G.; Pak, C.; Harkema, H.

    2013-01-01

    It is not known whether tepal senescence in Iris flowers is regulated by hormones. We applied hormones and hormone inhibitors to cut flowers and isolated tepals of Iris x hollandica cv. Blue Magic. Treatments with ethylene or ethylene antagonists indicated lack of ethylene involvement. Auxins or aux

  4. Delay of Iris flower senescence by cytokinins and jasmonates

    NARCIS (Netherlands)

    Doorn, van W.G.; Celikel, F.G.; Pak, C.; Harkema, H.

    2013-01-01

    It is not known whether tepal senescence in Iris flowers is regulated by hormones. We applied hormones and hormone inhibitors to cut flowers and isolated tepals of Iris x hollandica cv. Blue Magic. Treatments with ethylene or ethylene antagonists indicated lack of ethylene involvement. Auxins or

  5. Synthetic control of flowering in rice independent of the cultivation environment.

    Science.gov (United States)

    Okada, Ryo; Nemoto, Yasue; Endo-Higashi, Naokuni; Izawa, Takeshi

    2017-03-27

    For genetically homogeneous crops, the timing of flowering is determined largely by the cultivation environment and is strongly associated with the yield and quality of the harvest(1). Flowering time and other agronomical traits are often tightly correlated, which can lead to difficulty excluding the effects of flowering time when evaluating the characteristics of different genetic varieties(2). Here, we describe the development of transgenic rice plants whose flowering time can be controlled by specific agrochemicals. We first developed non-flowering rice plants by overexpressing a floral repressor gene, Grain number, plant height and heading date 7 (Ghd7)(3,4), to inhibit any environmentally induced spontaneous flowering. We then co-transformed plants with a rice florigen gene, Heading date 3a (Hd3a)(5), which is induced by the application of specific agrochemicals. This permitted the flowering time to be experimentally controlled regardless of the cultivation environment: some transgenic plants flowered only after agrochemical treatment. Furthermore, plant size and yield-related traits could, in some cases, be increased owing to both a longer duration of vegetative growth and an increased panicle size. This ability to control flowering time experimentally, independently of environmental variables, may lead to production of crops suitable for growth in different climates and facilitate breeding for various agronomical traits.

  6. Promoting flowering, lateral shoot outgrowth, leaf development, and flower abscission in tobacco plants overexpressing cotton FLOWERING LOCUS T (FT)-like gene GhFT1.

    Science.gov (United States)

    Li, Chao; Zhang, Yannan; Zhang, Kun; Guo, Danli; Cui, Baiming; Wang, Xiyin; Huang, Xianzhong

    2015-01-01

    FLOWERING LOCUS T (FT) encodes a mobile signal protein, recognized as major component of florigen, which has a central position in regulating flowering, and also plays important roles in various physiological aspects. A mode is recently emerging for the balance of indeterminate and determinate growth, which is controlled by the ratio of FT-like and TERMINAL FLOWER 1 (TFL1)-like gene activities, and has a strong influence on the floral transition and plant architecture. Orthologs of GhFT1 was previously isolated and characterized from Gossypium hirsutum. We demonstrated that ectopic overexpression of GhFT1 in tobacco, other than promoting flowering, promoted lateral shoot outgrowth at the base, induced more axillary bud at the axillae of rosette leaves, altered leaf morphology, increased chlorophyll content, had higher rate of photosynthesis and caused flowers abscission. Analysis of gene expression suggested that flower identity genes were significantly upregulated in transgenic plants. Further analysis of tobacco FT paralogs indicated that NtFT4, acting as flower inducer, was upregulated, whereas NtFT2 and NtFT3 as flower inhibitors were upregulated in transgenic plants under long-day conditions, but downregulated under short-day conditions. Our data suggests that sufficient level of transgenic cotton FT might disturb the balance of the endogenous tobacco FT paralogs of inducers and repressors and resulted in altered phenotype in transgenic tobacco, emphasizing the expanding roles of FT in regulating shoot architecture by advancing determine growth. Manipulating the ratio for indeterminate and determinate growth factors throughout FT-like and TFL1-like gene activity holds promise to improve plant architecture and enhance crop yield.

  7. Promoting Flowering, Lateral Shoot Outgrowth, Leaf Development, and Flower Abscission in Tobacco Plants Overexpressing Cotton FLOWERING LOCUS T (FT-Like Gene GhFT1

    Directory of Open Access Journals (Sweden)

    Chao eLi

    2015-06-01

    Full Text Available FLOWERING LOCUS T (FT encodes a mobile signal protein, recognized as major component of florigen, which has a central position in regulating flowering, and also plays important roles in various physiological aspects. A mode is recently emerging for the balance of indeterminate and determinate growth, which is controlled by the ratio of FT-like and TERMINAL FLOWER 1 (TFL1-like gene activities, and has a strong influence on the floral transition and plant architecture. Orthologs of GhFT1 was previously isolated and characterized from Gossypium hirsutum. We demonstrated that ectopic overexpression of GhFT1 in tobacco, other than promoting flowering, promoted lateral shoot outgrowth at the base, induced more axillary bud at the axillae of rosette leaves, altered leaf morphology, increased chlorophyll content, had higher photosynthesis and caused flowers abscission. Analysis of gene expression suggested that flower identity genes were significantly upregulated in transgenic plants. Further analysis of tobacco FT paralogs indicated that NtFT4, acting as flower inducer, was upregulated, whereas NtFT2 and NtFT3 as flower inhibitors were upregulated in transgenic plants under long-day conditions, but downregulated under short-day conditions. Our data suggested that sufficient level of foreign FT might disturb the balance of the endogenous FT paralogs of inducers and repressors and resulted in altered phenotype in transgenic tobacco, emphasizing the expanding roles of FT in regulating shoot architecture by advancing determine growth. Manipulating the ratio for indeterminate and determinate growth factors throughout FT-like and TFL1-like gene activity holds promise to improve plant architecture and enhance crop yield.

  8. Transcription factor PIF4 controls the thermosensory activation of flowering

    KAUST Repository

    Kumar, S. Vinod

    2012-03-21

    Plant growth and development are strongly affected by small differences in temperature. Current climate change has already altered global plant phenology and distribution, and projected increases in temperature pose a significant challenge to agriculture. Despite the important role of temperature on plant development, the underlying pathways are unknown. It has previously been shown that thermal acceleration of flowering is dependent on the florigen, FLOWERING LOCUS T (FT). How this occurs is, however, not understood, because the major pathway known to upregulate FT, the photoperiod pathway, is not required for thermal acceleration of flowering. Here we demonstrate a direct mechanism by which increasing temperature causes the bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) to activate FT. Our findings provide a new understanding of how plants control their timing of reproduction in response to temperature. Flowering time is an important trait in crops as well as affecting the life cycles of pollinator species. A molecular understanding of how temperature affects flowering will be important for mitigating the effects of climate change. © 2012 Macmillan Publishers Limited. All rights reserved.

  9. The multifaceted roles of FLOWERING LOCUS T in plant development.

    Science.gov (United States)

    Pin, P A; Nilsson, O

    2012-10-01

    One of the key developmental processes in flowering plants is the differentiation of the shoot apical meristem into a floral meristem. This transition is regulated through the integration of environmental and endogenous stimuli, involving a complex, hierarchical signalling network. In arabidopsis, the FLOWERING LOCUS T (FT) protein, a mobile signal recognized as a major component of florigen, has a central position in mediating the onset of flowering. FT-like genes seem to be involved in regulating the floral transition in all angiosperms examined to date. Evidence from molecular evolution studies suggests that the emergence of FT-like genes coincided with the evolution of the flowering plants. Hence, the role of FT in floral promotion is conserved, but appears to be restricted to the angiosperms. Besides flowering, FT-like proteins have also been identified as major regulatory factors in a wide range of developmental processes including fruit set, vegetative growth, stomatal control and tuberization. These multifaceted roles of FT-like proteins have resulted from extensive gene duplication events, which occurred independently in nearly all modern angiosperm lineages, followed by sub- or neo-functionalization. This review assesses the plethora of roles that FT-like genes have acquired during evolution and their implications in plant diversity, adaptation and domestication.

  10. Arabidopsis MSI1 functions in photoperiodic flowering time control.

    Science.gov (United States)

    Steinbach, Yvonne; Hennig, Lars

    2014-01-01

    Appropriate timing of flowering is crucial for crop yield and the reproductive success of plants. Flowering can be induced by a number of molecular pathways that respond to internal and external signals such as photoperiod, vernalization or light quality, ambient temperature and biotic as well as abiotic stresses. The key florigenic signal FLOWERING LOCUS T (FT) is regulated by several flowering activators, such as CONSTANS (CO), and repressors, such as FLOWERING LOCUS C (FLC). Chromatin modifications are essential for regulated gene expression, which often involves the well conserved MULTICOPY SUPRESSOR OF IRA 1 (MSI1)-like protein family. MSI1-like proteins are ubiquitous partners of various complexes, such as POLYCOMB REPRESSIVE COMPLEX2 or CHROMATIN ASSEMBLY FACTOR 1. In Arabidopsis, one of the functions of MSI1 is to control the switch to flowering. Arabidopsis MSI1 is needed for the correct expression of the floral integrator gene SUPPRESSOR OF CO 1 (SOC1). Here, we show that the histone-binding protein MSI1 acts in the photoperiod pathway to regulate normal expression of CO in long day (LD) photoperiods. Reduced expression of CO in msi1-mutants leads to failure of FT and SOC1 activation and to delayed flowering. MSI1 is needed for normal sensitivity of Arabidopsis to photoperiod, because msi1-mutants responded less than wild type to an intermittent LD treatment of plants grown in short days. Finally, genetic analysis demonstrated that MSI1 acts upstream of the CO-FT pathway to enable an efficient photoperiodic response and to induce flowering.

  11. Lotus Flowers

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    The lotus flower is a traditional subject for Chinese painters. Men of letters and painters depict it because although it grows from mud its blossoms are clean and charming, hence it has always been used to euphemize a man who keeps his noble mind even in unfavorable situations Young painter Xing Xiaolin features the lotus flowers again and

  12. Flower Development and Photoperiodic Control of Flowering in Rice

    Institute of Scientific and Technical Information of China (English)

    XIANG Chao; QU Li-jun; GAO Yong-ming; SHI Ying-yao

    2013-01-01

    Floral transition,which is referred to as a plant's transition from vegetative stage to reproductive stage,is considered to be a critical developmental switch in higher plants,for a timely flowering is a major factor of reproductive success.Endogenous and environmental cues,such as photoperiod,light quality,plant hormones concentrations and temperature,provide information to the plants whether the environment is favorable for flowering.These cues promote,or prevent,flowering through a complex genetic network,mediated by a careful orchestration of temporal and spatial gene expression.One of such cues is photoperiod.Rice (Oryza sativa L.) serves as a powerful model species for the understanding of flowering in higher plants,including flower development and photoperiodic control of flowering.In this review,we overviewed and discussed the flower development and its model.We also overviewed the photoperiodic pathways in rice flowering control,and summarized the pathways at molecular level.

  13. Recent advances of flowering locus T gene in higher plants.

    Science.gov (United States)

    Xu, Feng; Rong, Xiaofeng; Huang, Xiaohua; Cheng, Shuiyuan

    2012-01-01

    Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone and can induce flowering by long-distance transportation. In the present study, many FT-like genes were isolated, and the transgenic results show that FT gene can promote flowering in plants. This paper reviews the progress of the FT gene and its expression products to provide meaningful information for further studies of the functions of FT genes.

  14. 76 FR 20623 - Florigene Pty., Ltd.; Availability of Petition and Environmental Assessment for Determination of...

    Science.gov (United States)

    2011-04-13

    ... Chestnut, Policy Analyst, Biotechnology Regulatory Services, APHIS, 4700 River Road Unit 147, Riverdale, MD... from pansy and wishbone flower produces blue pigments in the rose lines, altering the flower color...

  15. Flowers & Weeds.

    Science.gov (United States)

    Flannery, Maura C.

    1996-01-01

    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)

  16. Flowers & Weeds.

    Science.gov (United States)

    Flannery, Maura C.

    1996-01-01

    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)

  17. EFFECT OF SPATIAL ARRANGEMENT AND FOLIAR APPLICATION OF GROWTH REGULATING HORMONE ON THE FLOWER HEAD DEVELOPMENT OF COCKSCOMB UNDER THE TROPICAL ARID ENVIRONMENT OF SOUTHERN PUNJAB, PAKISTAN

    Directory of Open Access Journals (Sweden)

    Ahsan Irshad

    2013-04-01

    Full Text Available This investigation was carried out at Experimental Farm, Faculty of Agriculture Science and Technology, Bahauddin Zakariya University, Multan (Pakistan. The objective of this study was to produce high quality Celosia flower head as cut flower under the harsh environmental conditions of southern Punjab by using different plant spacing and different concentrations of Gibberellin (GA3. The seedlings were grown by seed and then transplanted in the field in the first week of August. Seedlings were irrigated daily and fertilized with 100 ppm NPK solution with alternate irrigation before transplanting. Field was well prepared by irrigation and spading twice and adding about 1.5 kg Diammonium phosphate (DAP at the rate of 150 kg/hectare as phosphorus source, about 2 kg Muriate of Potash (MOP at the rate of 200 kg/hectare as potash source and about 1kg urea at the rate of 100 kg/hectare as nitrogen source prior to transplanting. Then, seedlings were transplanted in randomized complete block design. There were three levels/concentrations of GA3 (0, 25 and 50 mg/l and three levels of plant spacing (22.50, 30.00 and 37.50 cm making overall 9 treatments and these treatments were tested in 3 replications. The analysis of variance indicated that best results were achieved when plant spacing of 37.5cm was used in combination with GA3 application (at the rate of 50 mg/l where significant increase in chlorophyll contents, leaf area and number of leaves, fresh and dry weight of stem, flower diameter and fresh and dry weight of flower of Celosia cristata were found compared to all other treatments tested.

  18. [Pathways of flowering regulation in plants].

    Science.gov (United States)

    Liu, Yongping; Yang, Jing; Yang, Mingfeng

    2015-11-01

    Flowering, the floral transition from vegetative growth to reproductive growth, is induced by diverse endogenous and exogenous cues, such as photoperiod, temperature, hormones and age. Precise flowering time is critical to plant growth and evolution of species. The numerous renewal molecular and genetic results have revealed five flowering time pathways, including classical photoperiod pathway, vernalization pathway, autonomous pathway, gibberellins (GA) pathway and newly identified age pathway. These pathways take on relatively independent role, and involve extensive crosstalks and feedback loops. This review describes the complicated regulatory network of this floral transition to understand the molecular mechanism of flowering and provide references for further research in more plants.

  19. Selective deactivation of gibberellins below the shoot apex is critical to flowering but not to stem elongation of Lolium.

    Science.gov (United States)

    King, Rod W; Mander, Lewis N; Asp, Torben; MacMillan, Colleen P; Blundell, Cheryl A; Evans, Lloyd T

    2008-03-01

    Gibberellins (GAs) cause dramatic increases in plant height and a genetic block in the synthesis of GA(1) explains the dwarfing of Mendel's pea. For flowering, it is GA(5) which is important in the long-day (LD) responsive grass, Lolium. As we show here, GA(1) and GA(4) are restricted in their effectiveness for flowering because they are deactivated by C-2 hydroxylation below the shoot apex. In contrast, GA(5) is effective because of its structural protection at C-2. Excised vegetative shoot tips rapidly degrade [14C]GA(1), [14C]GA(4), and [14C]GA(20) (>80% in 6 h), but not [14C]GA(5). Coincidentally, genes encoding two 2beta-oxidases and a putative 16-17-epoxidase were most expressed just below the shoot apex (4 mm), expression of these GA deactivation genes is reduced, so allowing GA(1) and GA(4) to promote sub-apical stem elongation. Subsequently, GA degradation declines in florally induced shoot tips and these GAs can become active for floral development. Structural changes which stabilize GA(4) confirm the link between florigenicity and restricted GA 2beta-hydroxylation (e.g. 2alpha-hydroxylation and C-2 di-methylation). Additionally, a 2-oxidase inhibitor (Trinexapac Ethyl) enhanced the activity of applied GA(4), as did limiting C-16,17 epoxidation in 16,17-dihydro GAs or after C-13 hydroxylation. Overall, deactivation of GA(1) and GA(4) just below the shoot apex effectively restricts their florigenicity in Lolium and, conversely, with GA(5), C-2 and C-13 protection against deactivation allows its high florigenicity. Speculatively, such differences in GA access to the shoot apex of grasses may be important for separating floral induction from inflorescence emergence and thus could influence their survival under conditions of herbivore predation.

  20. Selective Deactivation of Gibberellins below the Shoot Apex is Critical to Flowering but Not to Stem Elongation of Lolium

    Institute of Scientific and Technical Information of China (English)

    Rod W.King; Lewis N.Mander; Torben Asp; Colleen P. MacMillan; Cheryl A.Blundell; Lloyd T.Evans

    2008-01-01

    Gibberellins (GAs) cause dramatic increases in plant height and a genetic block in the synthesis of GA1 explains the dwarfing of Mendel's pea.For flowering,it is GAs which is important in the long-day (LD) responsive grass,Lolium.As we show here,GA1 and GA4 are restricted in their effectiveness for flowering because they are deactivated by C-2 hydroxylation below the shoot apex.In contrast,GAs is effective because of its structural protection at C-2.Excised vegetative shoot tips rapidly degrade [14C]GA1,[14C]GA4,and [14C]GA20 (>80% in 6 h),but not [14C]GA5.Coincidentally,genes encoding two 2β-oxidases and a putative 16-17-epoxidase were most expressed just below the shoot apex (4 mm),expression of these GA deactivation genes is reduced,so allowing GA1 and GA4 to promote sub-apical stem elongation.Subsequently,GA degradation declines in florally induced shoot tips and these GAs can become active for floral development.Structural changes which stabilize GA4 confirm the link between florigenicity and restricted GA 2β-hydroxylation (e.g.2α-hydroxylation and C-2 di-methylation).Additionally,a 2-oxidase inhibitor (Trinexapac Ethyl) enhanced the activity of applied GA4,as did limiting C-16,17 epoxidation in 16,17-dihydro GAs or after C-13 hydroxylation.Overall,deactivation of GA1 and GA4 just below the shoot apex effectively restricts their florigenicity in Lolium and,conversely,with GAs,C-2 and C-13 protection against deactivation allows its high florigenicity.Speculatively,such differences in GA access to the shoot apex of grasses may be important for separating floral induction from inflorescence emergence and thus could influence their survival under conditions of herbivore predation.

  1. CmFTL2 is involved in the photoperiod- and sucrose-mediated control of flowering time in chrysanthemum.

    Science.gov (United States)

    Sun, Jing; Wang, Heng; Ren, Liping; Chen, Sumei; Chen, Fadi; Jiang, Jiafu

    2017-01-01

    The chrysanthemum genome harbors three FT-like genes: CmFTL1 and CmFTL3 are thought to act as regulators of floral induction under long-day (LD) and short-day (SD) conditions, respectively, whereas the function of CmFTL2 is currently unclear. The objective of the present research was to explore the function of CmFTL2 in the determination of flowering time of the photo-insensitive chrysanthemum cultivar 'Floral Yuuka', both in response to variation in the photoperiod and to the exogenous provision of sucrose. Spraying leaves of 'Floral Yuuka' plants with 50 mM sucrose accelerated flowering and increased the level of CmFTL2 transcription in the leaf more strongly than either CmFTL1 or FTL3 under both long and SD conditions. Transcription profiling indicated that all three CmFTL genes were upregulated during floral induction. The relationship of the CmFTL2 sequence with that of other members of the PEBP family suggested that its product contributes to the florigen rather than to the anti-florigen complex. The heterologous expression of CmFTL2 in the Arabidopsis thaliana ft-10 mutant rescued the mutant phenotype, showing that CmFTL2 could compensate for the absence of FT. These results suggest that CmFTL2 acts as a regulator of floral transition and responds to both the photoperiod and sucrose.

  2. Circadian clock and photoperiodic response in Arabidopsis: from seasonal flowering to redox homeostasis.

    Science.gov (United States)

    Shim, Jae Sung; Imaizumi, Takato

    2015-01-20

    Many of the developmental responses and behaviors in plants that occur throughout the year are controlled by photoperiod; among these, seasonal flowering is the most characterized. Molecular genetic and biochemical analyses have revealed the mechanisms by which plants sense changes in day length to regulate seasonal flowering. In Arabidopsis thaliana, induction of the expression of a florigen, FLOWERING LOCUS T (FT) protein, is a major output of the photoperiodic flowering pathway. The circadian clock coordinates the expression profiles and activities of the components in this pathway. Light-dependent control of CONSTANS (CO) transcription factor activity is a crucial part of the induction of the photoperiodic expression of FT. CO protein is stabilized only in the long day afternoon, which is when FT is induced. In this review, we summarize recent progress in the determination of the molecular architecture of the circadian clock and mechanisms underlying photoperiodic flowering. In addition, we introduce the molecular mechanisms of other biological processes, such as hypocotyl growth and reactive oxygen species production, which are also controlled by alterations in photoperiod.

  3. Over-expression of an FT-homologous gene of apple induces early flowering in annual and perennial plants.

    Science.gov (United States)

    Tränkner, Conny; Lehmann, Sandra; Hoenicka, Hans; Hanke, Magda-Viola; Fladung, Matthias; Lenhardt, Denise; Dunemann, Frank; Gau, Achim; Schlangen, Karin; Malnoy, Mickael; Flachowsky, Henryk

    2010-11-01

    The protein encoded by the FLOWERING LOCUS T (FT) gene from Arabidopsis thaliana seems to be the long-searched florigen, and over-expression of FT orthologues resulted in accelerated flower development in annual and perennial plants. In the present study, we isolated two allelic mRNA sequences of an FT-homologous gene from apple, which was designated as MdFT1. Using a SSR motif this gene was mapped on LG 12 of apple. Over-expression of MdFT1 in Arabidopsis and the commercially important tree species poplar and apple itself using the CaMV 35S or the Arabidopsis Suc2 promoter resulted in significant accelerated flowering compared with wild-type plants. Transgenic T(0) plants of Arabidopsis flowered 4-6 days on average earlier than wild-type Arabidopsis under LD conditions. Under short-day conditions Suc2::MdFT1 plants of the T(1)-generation flowered after 66 ± 18 days, while wild-type plants flowered about 22 days later. All transgenic Arabidopsis plants showed a normal habit except for the early flowering phenotype. Early flowering was detected 6-10 months after transformation in transgenic polar clones containing MdFT1 driven by the CaMV 35S, whereas plants of the transgenic apple clone T780 set up its first flowers during in vitro cultivation. Based on our results we conclude that MdFT1 is responsible for inducing flowering and that the function of the apple FT1 gene is conserved in annual herbaceous species as well as perennial woody species. Furthermore, we discuss the role of MdFT1 in flower development with regard to the findings of genetic studies on apple.

  4. In vitro flowering of Dendrobium candidum

    Institute of Scientific and Technical Information of China (English)

    王光远; 许智宏; 蔡德发; 蔡南海

    1997-01-01

    Dendrobium candidum, a wild orchid species from China, normally requires three to four years of cultivation before it can produce flowers. The effects of plant hormones and polyamines on flower initiation of this species in tissue culture were investigated. The addition of spermidine, or BA, or the combination of NAA and BA to the culture medium can induce protocorms or shoots to flower within three to six months with a frequency of 31.6% -45.8%. The flowering frequency can be further increased to 82.8 % on the average by pre-treatment of protocorms in an ABA-containing medium followed by transfer onto MS medium with BA. The induction of precocious flowering de-pends on the developmental stage of the experimental materials (protocorms, shoots and plantlets) used , and usually occurs only when root formation is inhibited.

  5. A petunia homeodomain-leucine zipper protein, PhHD-Zip, plays an important role in flower senescence

    Science.gov (United States)

    Flower senescence is mediated in part by changes of plant hormones, such as ethylene, cytokinin and abscisic acid (ABA). Ethylene is known to control flower senescence in many species, especially ethylene sensitive flowers, like petunia, carnation and rose. During flower senescence in petunia and ot...

  6. Three Medicago MtFUL genes have distinct and overlapping expression patterns during vegetative and reproductive development and 35S:MtFULb accelerates flowering and causes a terminal flower phenotype in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Mauren eJaudal

    2015-02-01

    Full Text Available The timing of the transition to flowering is carefully controlled by plants in order to optimise sexual reproduction and the ensuing production of seeds, grains and fruits. The genetic networks that regulate floral induction are best characterised in the temperate eudicot Arabidopsis in which the florigen gene FT plays a major role in promoting the transition to flowering. Legumes are an important plant group, but less is known about the regulation of their flowering time. In the model legume Medicago truncatula (Medicago, a temperate annual plant like Arabidopsis, flowering is induced by prolonged cold (vernalisation followed by long day lengths (LD. Recent molecular-genetic experiments have revealed that a FT-like gene, MtFTa1, is a central regulator of flowering time in Medicago. Here, we characterize the three Medicago FRUITFULL (FUL MADS transcription factors, MtFULa, MtFULb and MtFULc using phylogenetic analyses, gene expression profiling through developmental time courses, and functional analyses in transgenic plants. MtFULa and MtFULb have similarity in sequence and expression profiles under inductive environmental conditions during both vegetative and reproductive development while MtFULc is only up regulated in the apex after flowering in LD conditions. Sustained up regulation of MtFULs requires functional MtFTa1 but their transcript levels are not affected during cold treatment. Overexpression of MtFULa and MtFULb promotes flowering in transgenic Arabidopsis plants with an additional terminal flower phenotype on some 35S:MtFULb plants. An increase in transcript levels of the MtFULs was also observed in Medicago plants overexpressing MtFTa1. Our results suggest that the MtFULs are targets of MtFTa1. Overall, this work highlights the conserved functions of FUL-like genes in promoting flowering and other roles in plant development and thus contributes to our understanding of the genetic control of the flowering process in Medicago.

  7. In vitro flowering and pollen viability of cucumber

    Science.gov (United States)

    Flowers were produced on sterile cucumber (Cucumis sativus L.) plants grown in vitro from seed or from micropropagated shoots from stem fragments. Highest numbers of flowers on plants from both sources were produced on hormone-free MS medium as well as with 6 µM of kinetin (MSK). Plants cultured on ...

  8. Promotion and inhibition of flower formation in a dayneutral plant in grafts with a short-day plant and a long-day plant

    Energy Technology Data Exchange (ETDEWEB)

    Lang, A.; Chailakhyan, M.Kh.; Frolova, I.A.

    1977-06-01

    Flower formation in the dayneutral tobacco (Nicotiana tabacum L.) cultivar ''Trapezond'' was accelerated by graft union with the short-day tobacco ''Maryland Mammoth'' when the grafts were kept on short days and by graft union with the long-day plant N. silvestris L. when they were kept on long days. When Maryland Mammoth/Trapezond grafts were kept on long days, flower formation in Trapezond was not, or only slightly, delayed compared to Trapezond/Trapezond controls; but when N. silvestris/Trapezond grafts were kept on short days, flower formation in Trapezond was inhibited and its growth changed to dwarf-like habit. The former results indicate transmission of flower-promoting material(s) (''florigen'') from photoperiodic plants maintained under flower-promoting daylength conditions to a dayneutral graft partner; the latter indicate the presence in the long-day plant N. silvestris under short-day conditions of potent flower-inhibiting and growth-regulating material(s) that can also be transmitted to a day-neutral partner. Analogous flower-inhibitory materials seem not to be present, or to be present to a much lesser extent, in the short-day plant Maryland Mammoth under long-day conditions.

  9. Genetic interactions between diverged alleles of Early heading date 1 (Ehd1) and Heading date 3a (Hd3a)/ RICE FLOWERING LOCUS T1 (RFT1) control differential heading and contribute to regional adaptation in rice (Oryza sativa).

    Science.gov (United States)

    Zhao, Jing; Chen, Hongyi; Ren, Ding; Tang, Huiwu; Qiu, Rong; Feng, Jinglei; Long, Yunming; Niu, Baixiao; Chen, Danping; Zhong, Tianyu; Liu, Yao-Guang; Guo, Jingxin

    2015-11-01

    Initiation of flowering, also called heading, in rice (Oryza sativa) is determined by the florigens encoded by Heading date 3a (Hd3a) and RICE FLOWERING LOCUS T1 (RFT1). Early heading date 1 (Ehd1) regulates Hd3a and RFT1. However, different rice varieties have diverged alleles of Ehd1 and Hd3a/RFT1 and their genetic interactions remain largely unclear. Here we generated three segregating populations for different combinations of diverged Ehd1 and Hd3a/RFT1 alleles, and analyzed their genetic interactions between these alleles. We demonstrated that, in an ehd1 mutant background, Hd3a was silenced, but RFT1 was expressed (although at lower levels than in plants with a functional Ehd1) under short-day (SD) and long-day (LD) conditions. We identified a nonfunctional RFT1 allele (rft1); the lines carrying homozygous ehd1 and Hd3a/rft1 failed to induce the floral transition under SD and LD conditions. Like Hd3a, RFT1 also interacted with 14-3-3 proteins, the florigen receptors, but a nonfunctional RFT1 with a crucial E105K mutation failed to interact with 14-3-3 proteins. Furthermore, analyses of sequence variation and geographic distribution suggested that functional RFT1 alleles were selected during rice adaptation to high-latitude regions. Our results demonstrate the important roles of RFT1 in rice flowering and regional adaptation.

  10. Research progress ofphotoperiod regulatedgeneson flowering time in rice%水稻开花光周期调控相关基因研究进展

    Institute of Scientific and Technical Information of China (English)

    孔德艳; 陈守俊; 周立国; 高欢; 罗利军; 刘灶长

    2016-01-01

    Rice flowering regulation is an extremely complex process, which is controlled by genetic factors and external environment. Photoperiodic regulatory pathway ispivotal tocontrol flowering in rice, in which florigen genesHd3aandRTF1are at the core andthey are regulated byupstreamHd1-dependent,Ehd1-dependent,as well as bothHd1-andEhd1-independent pathways. The three pathways bring a variety of light signal information together toHd3aandRTF1for further integration,and then transmit the signals inthe form of florigen to the downstream flowering related genes.In thisreview, wesummarizethe research progress of photoperiod regulated geneson flowering time in rice,includingthe photoreceptors and circadian rhythm genes,the florigens,itsupstream, down-streamandinteracting genes.We hopeto provide a reference for in-depth study of rice flowering regulation.%水稻开花调控是一个极其复杂的生命过程,由自身遗传因素和外界环境共同决定。光周期途径是调控水稻开花的关键途径,在这个途径中成花素基因Hd3a和RTF1处于核心地位,其上游调控途径主要包括Hd1依赖途径、Ehd1依赖途径及不依赖于Hd1和Ehd1的途径。这3条途径在汇集了光信号的各种信息后,将信号在Hd3a 和 RTF1处整合,并通过成花素形式将信息传递给下游开花基因,调控水稻开花。本文从成花素、光信号感受基因和昼夜节律基因、成花素上游调控基因、互作蛋白和下游调控基因等几方面阐述水稻开花光周期调控相关基因的研究现状,为水稻开花调控的深入研究提供参考。

  11. Expression profiling of FLOWERING LOCUS T-like gene in alternate bearing 'Hass' avocado trees suggests a role for PaFT in avocado flower induction.

    Science.gov (United States)

    Ziv, Dafna; Zviran, Tali; Zezak, Oshrat; Samach, Alon; Irihimovitch, Vered

    2014-01-01

    In many perennials, heavy fruit load on a shoot decreases the ability of the plant to undergo floral induction in the following spring, resulting in a pattern of crop production known as alternate bearing. Here, we studied the effects of fruit load on floral determination in 'Hass' avocado (Persea americana). De-fruiting experiments initially confirmed the negative effects of fruit load on return to flowering. Next, we isolated a FLOWERING LOCUS T-like gene, PaFT, hypothesized to act as a phloem-mobile florigen signal and examined its expression profile in shoot tissues of on (fully loaded) and off (fruit-lacking) trees. Expression analyses revealed a strong peak in PaFT transcript levels in leaves of off trees from the end of October through November, followed by a return to starting levels. Moreover and concomitant with inflorescence development, only off buds displayed up-regulation of the floral identity transcripts PaAP1 and PaLFY, with significant variation being detected from October and November, respectively. Furthermore, a parallel microscopic study of off apical buds revealed the presence of secondary inflorescence axis structures that only appeared towards the end of November. Finally, ectopic expression of PaFT in Arabidopsis resulted in early flowering transition. Together, our data suggests a link between increased PaFT expression observed during late autumn and avocado flower induction. Furthermore, our results also imply that, as in the case of other crop trees, fruit-load might affect flowering by repressing the expression of PaFT in the leaves. Possible mechanism(s) by which fruit crop might repress PaFT expression, are discussed.

  12. Expression Profiling of FLOWERING LOCUS T-Like Gene in Alternate Bearing ‘Hass' Avocado Trees Suggests a Role for PaFT in Avocado Flower Induction

    Science.gov (United States)

    Ziv, Dafna; Zviran, Tali; Zezak, Oshrat; Samach, Alon; Irihimovitch, Vered

    2014-01-01

    In many perennials, heavy fruit load on a shoot decreases the ability of the plant to undergo floral induction in the following spring, resulting in a pattern of crop production known as alternate bearing. Here, we studied the effects of fruit load on floral determination in ‘Hass' avocado (Persea americana). De-fruiting experiments initially confirmed the negative effects of fruit load on return to flowering. Next, we isolated a FLOWERING LOCUS T-like gene, PaFT, hypothesized to act as a phloem-mobile florigen signal and examined its expression profile in shoot tissues of on (fully loaded) and off (fruit-lacking) trees. Expression analyses revealed a strong peak in PaFT transcript levels in leaves of off trees from the end of October through November, followed by a return to starting levels. Moreover and concomitant with inflorescence development, only off buds displayed up-regulation of the floral identity transcripts PaAP1 and PaLFY, with significant variation being detected from October and November, respectively. Furthermore, a parallel microscopic study of off apical buds revealed the presence of secondary inflorescence axis structures that only appeared towards the end of November. Finally, ectopic expression of PaFT in Arabidopsis resulted in early flowering transition. Together, our data suggests a link between increased PaFT expression observed during late autumn and avocado flower induction. Furthermore, our results also imply that, as in the case of other crop trees, fruit-load might affect flowering by repressing the expression of PaFT in the leaves. Possible mechanism(s) by which fruit crop might repress PaFT expression, are discussed. PMID:25330324

  13. Expression profiling of FLOWERING LOCUS T-like gene in alternate bearing 'Hass' avocado trees suggests a role for PaFT in avocado flower induction.

    Directory of Open Access Journals (Sweden)

    Dafna Ziv

    Full Text Available In many perennials, heavy fruit load on a shoot decreases the ability of the plant to undergo floral induction in the following spring, resulting in a pattern of crop production known as alternate bearing. Here, we studied the effects of fruit load on floral determination in 'Hass' avocado (Persea americana. De-fruiting experiments initially confirmed the negative effects of fruit load on return to flowering. Next, we isolated a FLOWERING LOCUS T-like gene, PaFT, hypothesized to act as a phloem-mobile florigen signal and examined its expression profile in shoot tissues of on (fully loaded and off (fruit-lacking trees. Expression analyses revealed a strong peak in PaFT transcript levels in leaves of off trees from the end of October through November, followed by a return to starting levels. Moreover and concomitant with inflorescence development, only off buds displayed up-regulation of the floral identity transcripts PaAP1 and PaLFY, with significant variation being detected from October and November, respectively. Furthermore, a parallel microscopic study of off apical buds revealed the presence of secondary inflorescence axis structures that only appeared towards the end of November. Finally, ectopic expression of PaFT in Arabidopsis resulted in early flowering transition. Together, our data suggests a link between increased PaFT expression observed during late autumn and avocado flower induction. Furthermore, our results also imply that, as in the case of other crop trees, fruit-load might affect flowering by repressing the expression of PaFT in the leaves. Possible mechanism(s by which fruit crop might repress PaFT expression, are discussed.

  14. Official Zhang Flower

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Tucked away at the highest elevation of any city in the world, Lhasa is filled with flowers bathed in warm sunlight. Whether in Barkor Street or in snaking alleys, one finds flowers in full bloom. They include the famous Gal-sang flower, azaleas, to be found in the mountains, Rho-diola which is used as a medicinal herb, and a kind of flower known as High Commissioner Zhang.

  15. Maternal temperature history activates Flowering Locus T in fruits to control progeny dormancy according to time of year.

    Science.gov (United States)

    Chen, Min; MacGregor, Dana R; Dave, Anuja; Florance, Hannah; Moore, Karen; Paszkiewicz, Konrad; Smirnoff, Nicholas; Graham, Ian A; Penfield, Steven

    2014-12-30

    Seasonal behavior is important for fitness in temperate environments but it is unclear how progeny gain their initial seasonal entrainment. Plants use temperature signals to measure time of year, and changes to life histories are therefore an important consequence of climate change. Here we show that in Arabidopsis the current and prior temperature experience of the mother plant is used to control germination of progeny seeds, via the activation of the florigen Flowering Locus T (FT) in fruit tissues. We demonstrate that maternal past and current temperature experience are transduced to the FT locus in silique phloem. In turn, FT controls seed dormancy through inhibition of proanthocyanidin synthesis in fruits, resulting in altered seed coat tannin content. Our data reveal that maternal temperature history is integrated through FT in the fruit to generate a metabolic signal that entrains the behavior of progeny seeds according to time of year.

  16. Bamboo Flowering from the Perspective of Comparative Genomics and Transcriptomics.

    Science.gov (United States)

    Biswas, Prasun; Chakraborty, Sukanya; Dutta, Smritikana; Pal, Amita; Das, Malay

    2016-01-01

    Bamboos are an important member of the subfamily Bambusoideae, family Poaceae. The plant group exhibits wide variation with respect to the timing (1-120 years) and nature (sporadic vs. gregarious) of flowering among species. Usually flowering in woody bamboos is synchronous across culms growing over a large area, known as gregarious flowering. In many monocarpic bamboos this is followed by mass death and seed setting. While in sporadic flowering an isolated wild clump may flower, set little or no seed and remain alive. Such wide variation in flowering time and extent means that the plant group serves as repositories for genes and expression patterns that are unique to bamboo. Due to the dearth of available genomic and transcriptomic resources, limited studies have been undertaken to identify the potential molecular players in bamboo flowering. The public release of the first bamboo genome sequence Phyllostachys heterocycla, availability of related genomes Brachypodium distachyon and Oryza sativa provide us the opportunity to study this long-standing biological problem in a comparative and functional genomics framework. We identified bamboo genes homologous to those of Oryza and Brachypodium that are involved in established pathways such as vernalization, photoperiod, autonomous, and hormonal regulation of flowering. Additionally, we investigated triggers like stress (drought), physiological maturity and micro RNAs that may play crucial roles in flowering. We also analyzed available transcriptome datasets of different bamboo species to identify genes and their involvement in bamboo flowering. Finally, we summarize potential research hurdles that need to be addressed in future research.

  17. Functional Analysis of OsKANADI1, A Florigen Hd3a Interacting Protein in Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Yekti Asih Purwestri

    2015-11-01

    Full Text Available OsKANADI1 is considered as a florigen Hd3a interacting protein. To study the function of OsKANADI1, the expression pattern of OsKANADI1 was performed by semiquantitative RT-PCR with various wild-type tissues in the floral transition stage. The results demonstrated that OsKANADI1 was expressed in all organs of wild-type plants, but was highest in roots and leaves. We hypothesize that OsKANADI1 is a transcription factor in rice because it contains a GARP domain and posses a nuclear localization signal. To determine whether OsKANADI1 encodes a nuclear protein, full-length OsKANADI1 fused to GFP was introduced into onion epidermis cells by particle bombardment. The result revealed that OsKANADI1 was localized in the nucleus, suggesting that OsKANADI1 may be a transcription factor. Functional analysis was carried out using a reverse genetics approach to generate gain of function mutant (overexpression and knockdown mutant (RNAi. The results showed that suppression of OsKANADI1 by RNAi displayed branching and increasing tiller number in several lines. This phenotype resembles to the Hd3a overexpressed plants indicating they possibly function in similar pathway.Key words : OsKANADI1, Transcription factor, Hd3a interacting protein, Rice

  18. Ehd4 encodes a novel and Oryza-genus-specific regulator of photoperiodic flowering in rice.

    Directory of Open Access Journals (Sweden)

    He Gao

    Full Text Available Land plants have evolved increasingly complex regulatory modes of their flowering time (or heading date in crops. Rice (Oryza sativa L. is a short-day plant that flowers more rapidly in short-day but delays under long-day conditions. Previous studies have shown that the CO-FT module initially identified in long-day plants (Arabidopsis is evolutionary conserved in short-day plants (Hd1-Hd3a in rice. However, in rice, there is a unique Ehd1-dependent flowering pathway that is Hd1-independent. Here, we report isolation and characterization of a positive regulator of Ehd1, Early heading date 4 (Ehd4. ehd4 mutants showed a never flowering phenotype under natural long-day conditions. Map-based cloning revealed that Ehd4 encodes a novel CCCH-type zinc finger protein, which is localized to the nucleus and is able to bind to nucleic acids in vitro and transactivate transcription in yeast, suggesting that it likely functions as a transcriptional regulator. Ehd4 expression is most active in young leaves with a diurnal expression pattern similar to that of Ehd1 under both short-day and long-day conditions. We show that Ehd4 up-regulates the expression of the "florigen" genes Hd3a and RFT1 through Ehd1, but it acts independently of other known Ehd1 regulators. Strikingly, Ehd4 is highly conserved in the Oryza genus including wild and cultivated rice, but has no homologs in other species, suggesting that Ehd4 is originated along with the diversification of the Oryza genus from the grass family during evolution. We conclude that Ehd4 is a novel Oryza-genus-specific regulator of Ehd1, and it plays an essential role in photoperiodic control of flowering time in rice.

  19. Putative sugarcane FT/TFL1 genes delay flowering time and alter reproductive architecture in Arabidopsis.

    Science.gov (United States)

    Coelho, Carla P; Minow, Mark A A; Chalfun-Júnior, Antonio; Colasanti, Joseph

    2014-01-01

    Agriculturally important grasses such as rice, maize, and sugarcane are evolutionarily distant from Arabidopsis, yet some components of the floral induction process are highly conserved. Flowering in sugarcane is an important factor that negatively affects cane yield and reduces sugar/ethanol production from this important perennial bioenergy crop. Comparative studies have facilitated the identification and characterization of putative orthologs of key flowering time genes in sugarcane, a complex polyploid plant whose genome has yet to be sequenced completely. Using this approach we identified phosphatidylethanolamine-binding protein (PEBP) gene family members in sugarcane that are similar to the archetypical FT and TFL1 genes of Arabidopsis that play an essential role in controlling the transition from vegetative to reproductive growth. Expression analysis of ScTFL1, which falls into the TFL1-clade of floral repressors, showed transcripts in developing leaves surrounding the shoot apex but not at the apex itself. ScFT1 was detected in immature leaves and apical regions of vegetatively growing plants and, after the floral transition, expression also occurred in mature leaves. Ectopic over-expression of ScTFL1 in Arabidopsis caused delayed flowering in Arabidopsis, as might be expected for a gene related to TFL1. In addition, lines with the latest flowering phenotype exhibited aerial rosette formation. Unexpectedly, over-expression of ScFT1, which has greatest similarity to the florigen-encoding FT, also caused a delay in flowering. This preliminary analysis of divergent sugarcane FT and TFL1 gene family members from Saccharum spp. suggests that their expression patterns and roles in the floral transition has diverged from the predicted role of similar PEBP family members.

  20. Putative sugarcane FT/TFL1 genes delay flowering time and alter reproductive architecture in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Carla P. Coelho

    2014-05-01

    Full Text Available Agriculturally important grasses such as rice, maize and sugarcane are evolutionarily distant from Arabidopsis, yet some components of the floral induction process are highly conserved. Flowering in sugarcane is an important factor that negatively affects cane yield and reduces sugar/ethanol production from this important perennial bioenergy crop. Comparative studies have facilitated the identification and characterization of putative orthologs of key flowering time genes in sugarcane, a complex polyploid plant whose genome has yet to be sequenced completely. Using this approach we identified phosphatidylethanolamine-binding protein (PEBP gene family members in sugarcane that are similar to the archetypical FT and TFL1 genes of Arabidopsis that play an essential role in controlling the transition from vegetative to reproductive growth. Expression analysis of ScTFL1, which falls into the TFL1-clade of floral repressors, showed transcripts in developing leaves surrounding the shoot apex but not at the apex itself. ScFT1 was detected in immature leaves and apical regions of vegetatively growing plants and, after the floral transition, expression also occurred in mature leaves. Ectopic over-expression of ScTFL1 in Arabidopsis caused delayed flowering in Arabidopsis, as might be expected for a gene related to TFL1. In addition, lines with the latest flowering phenotype exhibited aerial rosette formation. Unexpectedly, over-expression of ScFT1, which has greatest similarity to the florigen-encoding FT, also caused a delay in flowering. This preliminary analysis of divergent sugarcane FT and TFL1 gene family members from Saccharum spp. suggests that their expression patterns and roles in the floral transition has diverged from the predicted role of similar PEBP family members.

  1. Putative sugarcane FT/TFL1 genes delay flowering time and alter reproductive architecture in Arabidopsis

    Science.gov (United States)

    Coelho, Carla P.; Minow, Mark A. A.; Chalfun-Júnior, Antonio; Colasanti, Joseph

    2014-01-01

    Agriculturally important grasses such as rice, maize, and sugarcane are evolutionarily distant from Arabidopsis, yet some components of the floral induction process are highly conserved. Flowering in sugarcane is an important factor that negatively affects cane yield and reduces sugar/ethanol production from this important perennial bioenergy crop. Comparative studies have facilitated the identification and characterization of putative orthologs of key flowering time genes in sugarcane, a complex polyploid plant whose genome has yet to be sequenced completely. Using this approach we identified phosphatidylethanolamine-binding protein (PEBP) gene family members in sugarcane that are similar to the archetypical FT and TFL1 genes of Arabidopsis that play an essential role in controlling the transition from vegetative to reproductive growth. Expression analysis of ScTFL1, which falls into the TFL1-clade of floral repressors, showed transcripts in developing leaves surrounding the shoot apex but not at the apex itself. ScFT1 was detected in immature leaves and apical regions of vegetatively growing plants and, after the floral transition, expression also occurred in mature leaves. Ectopic over-expression of ScTFL1 in Arabidopsis caused delayed flowering in Arabidopsis, as might be expected for a gene related to TFL1. In addition, lines with the latest flowering phenotype exhibited aerial rosette formation. Unexpectedly, over-expression of ScFT1, which has greatest similarity to the florigen-encoding FT, also caused a delay in flowering. This preliminary analysis of divergent sugarcane FT and TFL1 gene family members from Saccharum spp. suggests that their expression patterns and roles in the floral transition has diverged from the predicted role of similar PEBP family members. PMID:24904616

  2. Heading date 1 (Hd1), an ortholog of Arabidopsis CONSTANS, is a possible target of human selection during domestication to diversify flowering times of cultivated rice.

    Science.gov (United States)

    Takahashi, Yasuyuki; Shimamoto, Ko

    2011-01-01

    During the domestication of rice (Oryza sativa L.), diversification of flowering time was important in expanding the areas of cultivation. Rice is a facultative short day (SD) plant and requires certain periods of dark to induce flowering. Heading date 1 (Hd1), a regulator of the florigen gene Hd3a, is one of the main factors used to generate diversity in flowering. Loss-of-function alleles of Hd1 are common in cultivated rice and cause the diversity of flowering time. However, it is unclear how these functional nucleotide polymorphisms of Hd1 accumulated in the course of evolution. Nucleotide polymorphisms within Hd1 and Hd3a were analyzed in 38 accessions of ancestral wild rice Oryza rufipogon and compared with those of cultivated rice. In contrast to cultivated rice, no nucleotide changes affecting Hd1 function were found in 38 accessions of wild rice ancestors. No functional changes were found in Hd3a in either cultivated or ancestral rice. A phylogenetic analysis indicated that evolution of the Hd1 alleles may have occurred independently in cultivars descended from various accessions of ancestral rice. The non-functional Hd1 alleles found in cultivated rice may be selected during domestication, because they were not found or very rare in wild ancestral rice. In contrast with Hd3a, which has been highly conserved, Hd1 may have undergone human selection to diversify the flowering times of rice during domestication or the early stage of the cultivation period.

  3. Influence of gibberellins on flower formation in Hyoscyamus niger L.

    OpenAIRE

    2014-01-01

    Gibberellins (GA4+7) and gibberellin-like substances isolated from generatively induced black henbane (Hyoscyamus niger L.) bring about the growth of shoots and a partial differentiation of axillary meristem in black henbane plants grown under non-inductive light conditions. Long-lasting application of gibberellins, however, did not result in full development of flowers in the majority of the plants investigated. Thus, it seems, that gibberellins are not specific flowering hormones in black h...

  4. Transcriptomic analysis of flower development in wintersweet (Chimonanthus praecox.

    Directory of Open Access Journals (Sweden)

    Daofeng Liu

    Full Text Available Wintersweet (Chimonanthus praecox is familiar as a garden plant and woody ornamental flower. On account of its unique flowering time and strong fragrance, it has a high ornamental and economic value. Despite a long history of human cultivation, our understanding of wintersweet genetics and molecular biology remains scant, reflecting a lack of basic genomic and transcriptomic data. In this study, we assembled three cDNA libraries, from three successive stages in flower development, designated as the flower bud with displayed petal, open flower and senescing flower stages. Using the Illumina RNA-Seq method, we obtained 21,412,928, 26,950,404, 24,912,954 qualified Illumina reads, respectively, for the three successive stages. The pooled reads from all three libraries were then assembled into 106,995 transcripts, 51,793 of which were annotated in the NCBI non-redundant protein database. Of these annotated sequences, 32,649 and 21,893 transcripts were assigned to gene ontology categories and clusters of orthologous groups, respectively. We could map 15,587 transcripts onto 312 pathways using the Kyoto Encyclopedia of Genes and Genomes pathway database. Based on these transcriptomic data, we obtained a large number of candidate genes that were differentially expressed at the open flower and senescing flower stages. An analysis of differentially expressed genes involved in plant hormone signal transduction pathways indicated that although flower opening and senescence may be independent of the ethylene signaling pathway in wintersweet, salicylic acid may be involved in the regulation of flower senescence. We also succeeded in isolating key genes of floral scent biosynthesis and proposed a biosynthetic pathway for monoterpenes and sesquiterpenes in wintersweet flowers, based on the annotated sequences. This comprehensive transcriptomic analysis presents fundamental information on the genes and pathways which are involved in flower development in

  5. A 1235711 Petalled Flower

    Indian Academy of Sciences (India)

    2016-11-01

    This article contains very simple mathematics and a lot ofcreativity. Here, we will sketch a 3-dimensional flower-likestructure, not using complicated equations but geometric ideasinstead. The speciality of 1235711 will be mentioned. At firstwe will study a general situation in 3-dimensional space $\\mathbb{R}^{3}$ and then we will take up the flower as an example of the generalcase.

  6. Hibiscus and Wild Flowers

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    Woodcut artist Zheng Shuang convinces the audience through her display of poetic emotion Benefiting from training in watercoior paintings early in life, strict literary sketch training as well, as 10 years study at the Central Academy of Fine Aris, Zheng has mare than 30 years teaching experience at the Ouangzhou Academy of Fine Aris "I"m a roadside grass, a wild flower," Zheng Shuang describes herself She said she often talks to nature-the mountains, the trees, the flowers and the

  7. Stars and Flowers, Flowers and Stars

    Science.gov (United States)

    Minti, Hari

    2012-12-01

    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.

  8. Growth Hormone

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Growth Hormone Share this page: Was this page helpful? Also known as: GH; Human Growth Hormone; HGH; Somatotropin; Growth Hormone Stimulation Test; Growth ...

  9. A Petunia homeodomain-leucine zipper protein, PhHD-Zip, plays an important role in flower senescence.

    Directory of Open Access Journals (Sweden)

    Xiaoxiao Chang

    Full Text Available Flower senescence is initiated by developmental and environmental signals, and regulated by gene transcription. A homeodomain-leucine zipper transcription factor, PhHD-Zip, is up-regulated during petunia flower senescence. Virus-induced gene silencing of PhHD-Zip extended flower life by 20% both in unpollinated and pollinated flowers. Silencing PhHD-Zip also dramatically reduced ethylene production and the abundance of transcripts of genes involved in ethylene (ACS, ACO, and ABA (NCED biosynthesis. Abundance of transcripts of senescence-related genes (SAG12, SAG29 was also dramatically reduced in the silenced flowers. Over-expression of PhHD-Zip accelerated petunia flower senescence. Furthermore, PhHD-Zip transcript abundance in petunia flowers was increased by application of hormones (ethylene, ABA and abiotic stresses (dehydration, NaCl and cold. Our results suggest that PhHD-Zip plays an important role in regulating petunia flower senescence.

  10. Involvement of ethylene in sex expression and female flower development in watermelon (Citrullus lanatus).

    Science.gov (United States)

    Manzano, Susana; Martínez, Cecilia; García, Juan Manuel; Megías, Zoraida; Jamilena, Manuel

    2014-12-01

    Although it is known that ethylene has a masculinizing effect on watermelon, the specific role of this hormone in sex expression and flower development has not been analyzed in depth. By using different approaches the present work demonstrates that ethylene regulates differentially two sex-related developmental processes: sexual expression, i.e. the earliness and the number of female flowers per plant, and the development of individual floral buds. Ethylene production in the shoot apex as well as in male, female and bisexual flowers demonstrated that the female flower requires much more ethylene than the male one to develop, and that bisexual flowers result from a decrease in ethylene production in the female floral bud. The occurrence of bisexual flowers was found to be associated with elevated temperatures in the greenhouse, concomitantly with a reduction of ethylene production in the shoot apex. External treatments with ethephon and AVG, and the use of Cucurbita rootstocks with different ethylene production and sensitivity, confirmed that, as occurs in other cucurbit species, ethylene is required to arrest the development of stamens in the female flower. Nevertheless, in watermelon ethylene inhibits the transition from male to female flowering and reduces the number of pistillate flowers per plant, which runs contrary to findings in other cucurbit species. The use of Cucurbita rootstocks with elevated ethylene production delayed the production of female flowers but reduced the number of bisexual flowers, which is associated with a reduced fruit set and altered fruit shape.

  11. The Myths behind Flower Names

    Institute of Scientific and Technical Information of China (English)

    白杰

    2014-01-01

    The Greek term for flower is Chloris. It is derived from the name of the Chloris, the goddess of vegetation, in Greek mythology, reasonably so, if we consider the great number of mythological tales linked to flowers of the Greek flowers. The use of flowers was widespread in Greece from time immemorial, since flowers are so important to us from the moment we are born. Flowers play an important role in mythology. As they morph from bud to bloom to faded and wilted petals, they assume various meanings linked to youth, life and death. They are associated with goddesses and legends, and are often attributed with certain powers and symbolism.

  12. A CONSTANS-like transcriptional activator, OsCOL13, functions as a negative regulator of flowering downstream of OsphyB and upstream of Ehd1 in rice.

    Science.gov (United States)

    Sheng, Peike; Wu, Fuqing; Tan, Junjie; Zhang, Huan; Ma, Weiwei; Chen, Liping; Wang, Jiachang; Wang, Jie; Zhu, Shanshan; Guo, Xiuping; Wang, Jiulin; Zhang, Xin; Cheng, Zhijun; Bao, Yiqun; Wu, Chuanyin; Liu, Xuanming; Wan, Jianmin

    2016-09-01

    Flowering time determines the adaptability of crop plants to different local environments, thus being one of the most important agronomic traits targeted in breeding programs. Photoperiod is one of the key factors that control flowering in plant. A number of genes that participate in the photoperiod pathway have been characterized in long-day plants such as Arabidopsis, as well as in short-day plants such as Oryza sativa. Of those, CONSTANS (CO) as a floral integrator promotes flowering in Arabidopsis under long day conditions. In rice, Heading date1 (Hd1), a homologue of CO, functions in an opposite way, which inhibits flowering under long day conditions and induces flowering under short day conditions. Here, we show that another CONSTANS-like (COL) gene, OsCOL13, negatively regulates flowering in rice under both long and short day conditions. Overexpression of OsCOL13 delays flowering regardless of day length. We also demonstrated that OsCOL13 has a constitutive and rhythmic expression pattern, and that OsCOL13 is localized to the nucleus. OsCOL13 displays transcriptional activation activity in the yeast assays and likely forms homodimers in vivo. OsCOL13 suppresses the florigen genes Hd3a and RFT1 by repressing Ehd1, but has no relationship with other known Ehd1 regulators as determined by using mutants or near isogenic lines. In addition, the transcriptional level of OsCOL13 significantly decreased in the osphyb mutant, but remained unchanged in the osphya and osphyc mutants. Thus, we conclude that OsCOL13 functions as a negative regulator downstream of OsphyB and upstream of Ehd1 in the photoperiodic flowering in rice.

  13. Isolation and functional analysis of CONSTANS-LIKE genes suggests that a central role for CONSTANS in flowering time control is not evolutionarily conserved in Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Albert eWong

    2014-09-01

    Full Text Available The zinc finger transcription factor CONSTANS has a well-established central role in the mechanism for photoperiod sensing in Arabidopsis, integrating light and circadian clock signals to upregulate the florigen gene FT under long-day but not short-day conditions. Although CONSTANS-like (COL genes in other species have also been shown to regulate flowering time, it is not clear how widely this central role in photoperiod sensing is conserved.Legumes are a major plant group and various legume species show significant natural variation for photoperiod responsive flowering. Orthologs of several Arabidopsis genes have been shown to participate in photoperiodic flowering in legumes, but the possible function of COL genes as integrators of the photoperiod response has not yet been examined in detail. Here we characterize the COL family in the temperate long-day legume Medicago truncatula, using expression analyses, reverse genetics, transient activation assays and Arabidopsis transformation. Our results provide several lines of evidence suggesting that COL genes are unlikely to have a central role in the photoperiod response mechanism in this species.

  14. Daffodil flower delay senescence in cut Iris flowers

    NARCIS (Netherlands)

    Doorn, van W.G.; Sinz, A.; Tomassen, M.M.M.

    2004-01-01

    Visible symptoms of tepal senescence in cut Iris x hollandica (cv. Blue Magic) flowers were delayed by placing one cut daffodil flower (Narcissus pseudonarcissus, cv. Carlton) in the same vase. Addition of mucilage, exuded by daffodil stems, to the vase water had the same effect as the flowering daf

  15. Orchid flowers: evolution and molecular development

    DEFF Research Database (Denmark)

    Johansen, Bo; Frederiksen, Signe Elisabeth

    2002-01-01

    MADS-box genes, ABS model, Orchid flower evolution, Gene expression in orchid flowers, in situ PCR......MADS-box genes, ABS model, Orchid flower evolution, Gene expression in orchid flowers, in situ PCR...

  16. Selecting Landscape Plants: Flowering Trees

    OpenAIRE

    Relf, Diane; Appleton, Bonnie Lee, 1948-2012

    2009-01-01

    This publication helps the reader to select wisely among the many species and varieties of flowering trees available. The following are considerations that should be taken into account when choosing flowering trees for the home landscape: selections factors, environmental responses, availability and adaptability, and flowering tree descriptions.

  17. Sex determination in flowering plants.

    Science.gov (United States)

    Dellaporta, S L; Calderon-Urrea, A

    1993-10-01

    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.

  18. Dual role of tree florigen activation complex component FD in photoperiodic growth control and adaptive response pathways.

    Science.gov (United States)

    Tylewicz, Szymon; Tsuji, Hiroyuki; Miskolczi, Pál; Petterle, Anna; Azeez, Abdul; Jonsson, Kristoffer; Shimamoto, Ko; Bhalerao, Rishikesh P

    2015-03-10

    A complex consisting of evolutionarily conserved FD, flowering locus T (FT) proteins is a regulator of floral transition. Intriguingly, FT orthologs are also implicated in developmental transitions distinct from flowering, such as photoperiodic control of bulbing in onions, potato tuberization, and growth cessation in trees. However, whether an FT-FD complex participates in these transitions and, if so, its mode of action, are unknown. We identified two closely related FD homologs, FD-like 1 (FDL1) and FD-like 2 (FDL2), in the model tree hybrid aspen. Using gain of function and RNAi-suppressed FDL1 and FDL2 transgenic plants, we show that FDL1 and FDL2 have distinct functions and a complex consisting of FT and FDL1 mediates in photoperiodic control of seasonal growth. The downstream target of the FT-FD complex in photoperiodic control of growth is Like AP1 (LAP1), a tree ortholog of the floral meristem identity gene APETALA1. Intriguingly, FDL1 also participates in the transcriptional control of adaptive response and bud maturation pathways, independent of its interaction with FT, presumably via interaction with abscisic acid insensitive 3 (ABI3) transcription factor, a component of abscisic acid (ABA) signaling. Our data reveal that in contrast to its primary role in flowering, FD has dual roles in the photoperiodic control of seasonal growth and stress tolerance in trees. Thus, the functions of FT and FD have diversified during evolution, and FD homologs have acquired roles that are independent of their interaction with FT.

  19. Phloem long-distance delivery of FLOWERING LOCUS T (FT) to the apex.

    Science.gov (United States)

    Yoo, Soo-Cheul; Chen, Cheng; Rojas, Maria; Daimon, Yasufumi; Ham, Byung-Kook; Araki, Takashi; Lucas, William J

    2013-08-01

    Cucurbita moschata FLOWERING LOCUS T-LIKE 2 (hereafter FTL2) and Arabidopsis thaliana (Arabidopsis) FLOWERING LOCUS T (FT), components of the plant florigenic signaling system, move long-distance through the phloem from source leaves to the vegetative apex where they mediate floral induction. The mechanisms involved in long-distance trafficking of FT/FTL2 remain to be elucidated. In this study, we identified the critical motifs on both FT and FTL2 required for cell-to-cell trafficking through mutant analyses using a zucchini yellow mosaic virus expression vector. Western blot analysis, performed on phloem sap collected from just beneath the vegetative apex of C. moschata plants, established that all mutant proteins tested retained the ability to enter the phloem translocation stream. However, immunolocalization studies revealed that a number of these FTL2/FT mutants were defective in the post-phloem zone, suggesting that a regulation mechanism for FT trafficking exists in the post-phloem unloading step. The selective movements of FT/FTL2 were further observed by microinjection and trichome rescue studies, which revealed that FT/FTL2 has the ability to dilate plasmodesmata microchannels during the process of cell-to-cell trafficking, and various mutants were compromised in their capacity to traffic through plasmodesmata. Based on these findings, a model is presented to account for the mechanism by which FT/FTL2 enters the phloem translocation stream and subsequently exits the phloem and enters the apical tissue, where it initiates the vegetative to floral transition.

  20. A Map-Based Cloning Strategy Employing a Residual Heterozygous Line Reveals that the GIGANTEA Gene Is Involved in Soybean Maturity and Flowering

    Science.gov (United States)

    Watanabe, Satoshi; Xia, Zhengjun; Hideshima, Rumiko; Tsubokura, Yasutaka; Sato, Shusei; Yamanaka, Naoki; Takahashi, Ryoji; Anai, Toyoaki; Tabata, Satoshi; Kitamura, Keisuke; Harada, Kyuya

    2011-01-01

    Flowering is indicative of the transition from vegetative to reproductive phase, a critical event in the life cycle of plants. In soybean (Glycine max), a flowering quantitative trait locus, FT2, corresponding to the maturity locus E2, was detected in recombinant inbred lines (RILs) derived from the varieties “Misuzudaizu” (ft2/ft2; JP28856) and “Moshidou Gong 503” (FT2/FT2; JP27603). A map-based cloning strategy using the progeny of a residual heterozygous line (RHL) from the RIL was employed to isolate the gene responsible for this quantitative trait locus. A GIGANTEA ortholog, GmGIa (Glyma10g36600), was identified as a candidate gene. A common premature stop codon at the 10th exon was present in the Misuzudaizu allele and in other near isogenic lines (NILs) originating from Harosoy (e2/e2; PI548573). Furthermore, a mutant line harboring another premature stop codon showed an earlier flowering phenotype than the original variety, Bay (E2/E2; PI553043). The e2/e2 genotype exhibited elevated expression of GmFT2a, one of the florigen genes that leads to early flowering. The effects of the E2 allele on flowering time were similar among NILs and constant under high (43°N) and middle (36°N) latitudinal regions in Japan. These results indicate that GmGIa is the gene responsible for the E2 locus and that a null mutation in GmGIa may contribute to the geographic adaptation of soybean. PMID:21406680

  1. Regulation of arabidopsis flowering by the histone mark readers MRG1/2 via interaction with CONSTANS to modulate FT expression.

    Directory of Open Access Journals (Sweden)

    Zhongyuan Bu

    2014-09-01

    Full Text Available Day-length is important for regulating the transition to reproductive development (flowering in plants. In the model plant Arabidopsis thaliana, the transcription factor CONSTANS (CO promotes expression of the florigen FLOWERING LOCUS T (FT, constituting a key flowering pathway under long-day photoperiods. Recent studies have revealed that FT expression is regulated by changes of histone modification marks of the FT chromatin, but the epigenetic regulators that directly interact with the CO protein have not been identified. Here, we show that the Arabidopsis Morf Related Gene (MRG group proteins MRG1 and MRG2 act as H3K4me3/H3K36me3 readers and physically interact with CO to activate FT expression. In vitro binding analyses indicated that the chromodomains of MRG1 and MRG2 preferentially bind H3K4me3/H3K36me3 peptides. The mrg1 mrg2 double mutant exhibits reduced mRNA levels of FT, but not of CO, and shows a late-flowering phenotype under the long-day but not short-day photoperiod growth conditions. MRG2 associates with the chromatin of FT promoter in a way dependent of both CO and H3K4me3/H3K36me3. Vice versa, loss of MRG1 and MRG2 also impairs CO binding at the FT promoter. Crystal structure analyses of MRG2 bound with H3K4me3/H3K36me3 peptides together with mutagenesis analysis in planta further demonstrated that MRG2 function relies on its H3K4me3/H3K36me3-binding activity. Collectively, our results unravel a novel chromatin regulatory mechanism, linking functions of MRG1 and MRG2 proteins, H3K4/H3K36 methylations, and CO in FT activation in the photoperiodic regulation of flowering time in plants.

  2. Chemical control of flowering time

    DEFF Research Database (Denmark)

    Ionescu, Irina Alexandra; Møller, Birger Lindberg; Sánchez Pérez, Raquel

    2017-01-01

    the transition to flowering as well as flower opening. Increased emphasis on research within this area has the potential to counteract the negative effects of global warming on flowering time, especially in perennial crop plants. Perennial crops have a requirement for winter chill, but winters become...... increasingly warm in temperate regions. This has dramatic effects on crop yield. Different strategies are therefore being developed to engineer flowering time to match local growing conditions. The majority of these efforts are within plant breeding, which benefits from a substantial amount of knowledge...... on the genetic aspects of flowering time regulation in annuals, but less so in perennials. An alternative to plant breeding approaches is to engineer flowering time chemically via the external application of flower-inducing compounds. This review discusses a variety of exogenously applied compounds used in fruit...

  3. The quest for molecular regulation underlying unisexual flower development

    Directory of Open Access Journals (Sweden)

    Rómulo eSobral

    2016-02-01

    Full Text Available The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious and hermaphroditic individuals. Here, we review the paper entitled Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber published in 2014 in the Frontiers of Plant Science (volume 5 | Article 599 and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs.

  4. The Quest for Molecular Regulation Underlying Unisexual Flower Development

    Science.gov (United States)

    Sobral, Rómulo; Silva, Helena G.; Morais-Cecílio, Leonor; Costa, Maria M. R.

    2016-01-01

    The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious, and hermaphroditic individuals. Here, we review the paper entitled “Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber” published in 2014 in the Frontiers of Plant Science (volume 5 |Article 599) and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs. PMID:26925078

  5. Effects of Phytoestrogen Extracts Isolated from Elder Flower on Hormone Production and Receptor Expression of Trophoblast Tumor Cells JEG-3 and BeWo, as well as MCF7 Breast Cancer Cells

    Science.gov (United States)

    Schröder, Lennard; Richter, Dagmar Ulrike; Piechulla, Birgit; Chrobak, Mareike; Kuhn, Christina; Schulze, Sandra; Abarzua, Sybille; Jeschke, Udo; Weissenbacher, Tobias

    2016-01-01

    Herein we investigated the effect of elderflower extracts (EFE) and of enterolactone/enterodiol on hormone production and proliferation of trophoblast tumor cell lines JEG-3 and BeWo, as well as MCF7 breast cancer cells. The EFE was analyzed by mass spectrometry. Cells were incubated with various concentrations of EFE. Untreated cells served as controls. Supernatants were tested for estradiol production with an ELISA method. Furthermore, the effect of the EFE on ERα/ERβ/PR expression was assessed by immunocytochemistry. EFE contains a substantial amount of lignans. Estradiol production was inhibited in all cells in a concentration-dependent manner. EFE upregulated ERα in JEG-3 cell lines. In MCF7 cells, a significant ERα downregulation and PR upregulation were observed. The control substances enterolactone and enterodiol in contrast inhibited the expression of both ER and of PR in MCF7 cells. In addition, the production of estradiol was upregulated in BeWo and MCF7 cells in a concentration dependent manner. The downregulating effect of EFE on ERα expression and the upregulation of the PR expression in MFC-7 cells are promising results. Therefore, additional unknown substances might be responsible for ERα downregulation and PR upregulation. These findings suggest potential use of EFE in breast cancer prevention and/or treatment and warrant further investigation. PMID:27740591

  6. Flower consumption lures investment

    Institute of Scientific and Technical Information of China (English)

    ShiSesheng

    2003-01-01

    In the Netherlands the annual fresh flower consumption is 150 items per person, in France it is 80, in the US it is 30, in Japan the money involved amounts to US$11 billion, but in urban China, this is less than I0. Globally when per capita GDP in a country or region goes up to US$6,000, flower consumption will go up too. As per capita GDP in Shanghai isgoing from US$5,000 to US$7,500, the municipal government should include the construction of floral markets as part of its infrastructural development, just as the construction of urban forests, urban parks, urban greenery, and urban environmental investment. The fostering of local floral markets also require joint efforts from the society at large in terms of finance.

  7. Butterfly Longing for Flowers

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    "BUTTERFLY Longs for Flowers" (Die Lian Hua)was the name of a melody famous in the TangDynasty (618-907). It was later used as the nameof tunes to which poems were composed. As thename suggests, butteffies and flowers attract anddepend on each other; a natural occurrence andyet full of worldly beauty. The Yu couple havebeen researching customs and dance for a longtime, over the course of which they have collectedcountless materials that have allowed theaficionados to appreciate and conclude on theiruse. Based on their findings they create folkdances and perform them on stage. Their love,pursuit and understanding of the art displays timeand again the beauty of a butterfly longing forflowers.

  8. How flowers catch raindrops

    CERN Document Server

    Amador, Guillermo; Hu, David

    2011-01-01

    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 the plants' fruit bodies, fabricated using a 3D printer. Particular attention was paid to optimizing flower geometries and drop impact parameters to propel seeds the farthest distance. We find off-center impacts are the most effective for dispersing seeds. Such impacts amplify the raindrop's speed, encapsulate seeds within drops, and direct the seed trajectory at angles optimal for long-distance dispersal.

  9. Let the flowers grow…

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    The Environmental part of CERN Safety policy is represented by a flower whose petals are the various domains of its application. The Environment Services section within the Occupational Health and Safety and Environmental Protection Unit is in charge of monitoring the impact of the Laboratory on the environment. You are called on to make every effort to reduce this impact as much as reasonably achievable. Read why and how…   A physics Laboratory occupying a territory of the size of a small village, with sites scattered across an even larger area, has a considerable potential impact on the environment. Energy and water consumption, waste management... these are all aspects of the same problem or, in the representation, petals of the same flower. Each one should be carefully studied and dealt with. The nine members of the Environment Services section deal with matters that concern these and other aspects of the CERN's policy for the protection of the environment. “...

  10. Transcriptomic Analysis of Flower Blooming in Jasminum sambac through De Novo RNA Sequencing

    Directory of Open Access Journals (Sweden)

    Yong-Hua Li

    2015-06-01

    Full Text Available Flower blooming is a critical and complicated plant developmental process in flowering plants. However, insufficient information is available about the complex network that regulates flower blooming in Jasminum sambac. In this study, we used the RNA-Seq platform to analyze the molecular regulation of flower blooming in J. sambac by comparing the transcript profiles at two flower developmental stages: budding and blooming. A total of 4577 differentially-expressed genes (DEGs were identified between the two floral stages. The Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses revealed that the DEGs in the “oxidation-reduction process”, “extracellular region”, “steroid biosynthesis”, “glycosphingolipid biosynthesis”, “plant hormone signal transduction” and “pentose and glucuronate interconversions” might be associated with flower development. A total of 103 and 92 unigenes exhibited sequence similarities to the known flower development and floral scent genes from other plants. Among these unigenes, five flower development and 19 floral scent unigenes exhibited at least four-fold differences in expression between the two stages. Our results provide abundant genetic resources for studying the flower blooming mechanisms and molecular breeding of J. sambac.

  11. Transcriptomic Analysis of Flower Blooming in Jasminum sambac through De Novo RNA Sequencing.

    Science.gov (United States)

    Li, Yong-Hua; Zhang, Wei; Li, Yong

    2015-06-10

    Flower blooming is a critical and complicated plant developmental process in flowering plants. However, insufficient information is available about the complex network that regulates flower blooming in Jasminum sambac. In this study, we used the RNA-Seq platform to analyze the molecular regulation of flower blooming in J. sambac by comparing the transcript profiles at two flower developmental stages: budding and blooming. A total of 4577 differentially-expressed genes (DEGs) were identified between the two floral stages. The Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses revealed that the DEGs in the "oxidation-reduction process", "extracellular region", "steroid biosynthesis", "glycosphingolipid biosynthesis", "plant hormone signal transduction" and "pentose and glucuronate interconversions" might be associated with flower development. A total of 103 and 92 unigenes exhibited sequence similarities to the known flower development and floral scent genes from other plants. Among these unigenes, five flower development and 19 floral scent unigenes exhibited at least four-fold differences in expression between the two stages. Our results provide abundant genetic resources for studying the flower blooming mechanisms and molecular breeding of J. sambac.

  12. Interconnection between flowering time control and activation of systemic acquired resistance.

    Science.gov (United States)

    Banday, Zeeshan Z; Nandi, Ashis K

    2015-01-01

    The ability to avoid or neutralize pathogens is inherent to all higher organisms including plants. Plants recognize pathogens through receptors, and mount resistance against the intruders, with the help of well-elaborated defense arsenal. In response to some localinfections, plants develop systemic acquired resistance (SAR), which provides heightened resistance during subsequent infections. Infected tissues generate mobile signaling molecules that travel to the systemic tissues, where they epigenetically modify expression o a set of genes to initiate the manifestation of SAR in distant tissues. Immune responses are largely regulated at transcriptional level. Flowering is a developmental transition that occurs as a result of the coordinated action of large numbers of transcription factors that respond to intrinsic signals and environmental conditions. The plant hormone salicylic acid (SA) which is required for SAR activation positively regulates flowering. Certain components of chromatin remodeling complexes that are recruited for suppression of precocious flowering are also involved in suppression of SAR in healthy plants. FLOWERING LOCUS D, a putative histone demethylase positively regulates SAR manifestation and flowering transition in Arabidopsis. Similarly, incorporation of histone variant H2A.Z in nucleosomes mediated by PHOTOPERIOD-INDEPENDENT EARLY FLOWERING 1, an ortholog of yeast chromatin remodeling complex SWR1, concomitantly influences SAR and flowering time. SUMO conjugation and deconjugation mechanisms also similarly affect SAR and flowering in an SA-dependent manner. The evidences suggest a common underlying regulatory mechanism for activation of SAR and flowering in plants.

  13. Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

    Institute of Scientific and Technical Information of China (English)

    Tao Liu; Yunqian Hu; Xiaoxian Li

    2008-01-01

    To elucidate the possible functions of endogenous hormones in the flowering of chestnut, concentrations of four endogenous hormones [indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA), zeatin riboside (ZR)) and the soluble sugars content were measured in both normal and developmentally abnormal Chinese chestnut (Castanea mollissima) during flowering and fruiting stages. Our results showed that the contents of ZR, ABA, and GA exhibited a significant different pattern in normal trees from that in abnormal trees, while the contents of IAA and soluble sugars showed a similar change pattern between them. These results suggest that quantitative changes in endogenous hormones may correspond to different flowering and fruiting mechanisms.

  14. NO FLOWERING IN SHORT DAY (NFL) is a bHLH transcription factor that promotes flowering specifically under short-day conditions in Arabidopsis.

    Science.gov (United States)

    Sharma, Nidhi; Xin, Ruijiao; Kim, Dong-Hwan; Sung, Sibum; Lange, Theo; Huq, Enamul

    2016-02-15

    Flowering in plants is a dynamic and synchronized process where various cues including age, day length, temperature and endogenous hormones fine-tune the timing of flowering for reproductive success. Arabidopsis thaliana is a facultative long day (LD) plant where LD photoperiod promotes flowering. Arabidopsis still flowers under short-day (SD) conditions, albeit much later than in LD conditions. Although factors regulating the inductive LD pathway have been extensively investigated, the non-inductive SD pathway is much less understood. Here, we identified a key basic helix-loop-helix transcription factor called NFL (NO FLOWERING IN SHORT DAY) that is essential to induce flowering specifically under SD conditions in Arabidopsis. nfl mutants do not flower under SD conditions, but flower similar to the wild type under LD conditions. The no-flowering phenotype in SD is rescued either by exogenous application of gibberellin (GA) or by introducing della quadruple mutants in the nfl background, suggesting that NFL acts upstream of GA to promote flowering. NFL is expressed at the meristematic regions and NFL is localized to the nucleus. Quantitative RT-PCR assays using apical tissues showed that GA biosynthetic genes are downregulated and the GA catabolic and receptor genes are upregulated in the nfl mutant compared with the wild type, consistent with the perturbation of the endogenous GA biosynthetic and catabolic intermediates in the mutant. Taken together, these data suggest that NFL is a key transcription factor necessary for promotion of flowering under non-inductive SD conditions through the GA signaling pathway. © 2016. Published by The Company of Biologists Ltd.

  15. Occupational allergy caused by flowers.

    Science.gov (United States)

    de Jong, N W; Vermeulen, A M; Gerth van Wijk, R; de Groot, H

    1998-02-01

    We describe 14 consecutive patients with complaints due to the handling of flowers. The symptoms varied from allergic rhinoconjunctivitis and asthma to urticaria. Most patients had professions in the flower industry. Skin prick tests (SPT) were performed with home-made pollen extracts from 17 different flowers known to be the most commonly grown and sold in The Netherlands RAST against mugwort, chrysanthemum, and solidago was performed. The diagnosis of atopy against flowers was based on work-related symptoms due to the handling of flowers, positive SPT with flower extracts, and positive RAST. The concordance between SPT and case history was 74%, and that between SPT and RAST was 77% Extensive cross-sensitization was seen to pollen of several members of the Compositae family (e.g., Matricaria, chrysanthemum, solidago) and to pollen of the Amaryllidaceae family (Alstroemeria and Narcissus). Homemade flower extracts can be used to confirm IgE-mediated flower allergy. Mugwort can be used as a screening test for possible flower allergy. For most patients, the allergy led to a change of profession.

  16. The Staunch Beauty of Flowers

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    MANY women like to collect dried flowers. Unable to bear the sight of beautiful blossoms withering, they press them between the leaves of books. As time passes, the original fresh flowers turn into thin pale-colored specimens, but a careful viewer will notice that they have taken on a new grace—just like Ren Jie herself; though no longer young, she has managed to create beauty out of her later life. Ren Jie’s love of flowers dates back to her childhood, when she started to collect flower specimens. As she grew up, she learned how to paint; later, she

  17. Stop and Paint the Flowers.

    Science.gov (United States)

    Phillips, Shelley

    2002-01-01

    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)

  18. Flowers free from the environment?

    NARCIS (Netherlands)

    Pijl, van der L.

    1958-01-01

    At the jubilee of Professor Lam it seems suitable to contribute a paper on the flower as a functional unit, though it is in the form of a kind of book-review. Lam himself wrote on the more fundamental connections between flowering and lower plants and on the basal morphological elements of the

  19. Dominus for cut flower production

    Science.gov (United States)

    Fumigation with methyl bromide was the principal method of soilborne pest control in cut flower production. Many cut flower growers in Florida have ceased production, but those that remain are restricted in the fumigants that they are able to utilize due to proximity to potable water sources and oc...

  20. Teaching Flowers: A Photo Essay

    Science.gov (United States)

    Hewson, Federico

    2017-01-01

    "Teaching Flowers" reflects on humanity's deep connections to horticulture by gathering varied thoughts from seminal writers in the field. In addition, this visual article draws attention to labor issues within the U.S. floral industry by documenting the author's exploration of flowers as social sculpture in New York City.

  1. OsBBX14 delays heading date by repressing florigen gene expression under long and short-day conditions in rice.

    Science.gov (United States)

    Bai, Bo; Zhao, Jie; Li, Yaping; Zhang, Fang; Zhou, Jinjun; Chen, Fan; Xie, Xianzhi

    2016-06-01

    B-box (BBX) proteins are zinc finger proteins containing B-box domains, which have roles in Arabidopsis growth and development. However, little is known concerning rice BBXs. Herein, we identified a rice BBX protein, Oryza sativa BBX14 (OsBBX14). OsBBX14 is highly expressed in flag leaf blades. OsBBX14 expression shows a diurnal rhythm under photoperiodic conditions and subsequent continuous white light. OsBBX14 is located in the nucleus and has transcriptional activation potential. OsBBX14-overexpression (OsBBX14-OX) lines exhibited delayed heading date under long-day (LD) and short-day (SD) conditions, whereas RNAi lines of OsBBX14 lines had similar heading dates to the WT. The florigen genes, Hd3a and RFT1, were downregulated in the OsBBX14-OX lines under LD and SD conditions. Under LD conditions, Hd1 was expressed higher in the OsBBX14-OX lines than in the wild type (WT), and the rhythmic expression of circadian clock genes, OsLHY and OsPRR1, was changed in OsBBX14-OX lines. Thus, OsBBX14 acts as a floral repressor by promoting Hd1 expression under LD conditions, probably because of crosstalk with the circadian clock. Under SD conditions, Ehd1 expression was reduced in OsBBX14-OX lines, but Hd1 and circadian clock gene expressions were unaffected, indicating that OsBBX14 acts as a repressor of Ehd1. Our findings suggested that OsBBX14 regulates heading date differently under LD and SD conditions.

  2. Promotion of flowering by Apple latent spherical virus vector and virus elimination at high temperature allow accelerated breeding of apple and pear

    Directory of Open Access Journals (Sweden)

    Noriko eYamagishi

    2016-02-01

    Full Text Available Plant viral vectors are superior tools for genetic manipulation, allowing rapid induction or suppression of expression of a target gene in plants. This is a particularly effective technology for use in breeding fruit trees, which are difficult to manipulate using recombinant DNA technologies. We reported previously that if apple seed embryos (cotyledons are infected with an Apple latent spherical virus (ALSV vector (ALSV-AtFT/MdTFL1 concurrently expressing the Arabidopsis thaliana florigen (AtFT gene and suppressing the expression of the apple MdTFL1-1 gene, the period prior to initial flowering (generally lasts 5–12 years will be reduced to about two months. In this study, we examined whether or not ALSV vector technology can be used to promote flowering in pear, which undergoes a very long juvenile period (germination to flowering similar to that of apple. The MdTFL1 sequence in ALSV-AtFT/MdTFL1 was replaced with a portion of the pear PcTFL1-1 gene. The resulting virus (ALSV-AtFT/PcTFL1 and ALSV-AtFT/MdTFL1 were used individually for inoculation to pear cotyledons immediately after germination in two inoculation groups. Those inoculated with ALSV-AtFT/MdTFL1 and ALSV-AtFT/PcTFL1 then initiated flower bud formation starting one to three months after inoculation, and subsequently exhibited continuous flowering and fruition by pollination. Conversely, Japanese pear exhibited extremely low systemic infection rates when inoculated with ALSV-AtFT/MdTFL1, and failed to exhibit any induction of flowering. We also developed a simple method for eliminating ALSV vectors from infected plants. An evaluation of the method for eliminating the ALSV vectors from infected apple and pear seedlings revealed that a four-week high-temperature (37˚C incubation of ALSV-infected apples and pears disabled the movement of ALSV to new growing tissues. This demonstrates that only high-temperature treatment can easily eliminate ALSV from infected fruit trees. A method

  3. Se14, encoding a JmjC domain-containing protein, plays key roles in long-day suppression of rice flowering through the demethylation of H3K4me3 of RFT1.

    Directory of Open Access Journals (Sweden)

    Takayuki Yokoo

    Full Text Available Floral transition from the vegetative to the reproductive growth phase is a major change in the plant life cycle and a key factor in reproductive success. In rice (Oryza sativa L., a facultative short-day plant, numerous flowering time and flower formation genes that control floral transition have been identified and their physiological effects and biochemical functions have been clarified. In the present study, we used a Se14-deficient mutant line (HS112 and other flowering mutant lines to investigate the photoperiodic response, chromosomal location and function in the photoperiod sensitivity of the Se14 gene. We also studied the interactive effects of this locus with other crucial flowering time genes. We found that Se14 is independent of the known photoperiod-sensitive genes, such as Hd1 and Ghd7, and is identical to Os03g0151300, which encodes a Jumonji C (JmjC domain-containing protein. Expression analysis revealed that the expressions of RFT1, a floral initiator known as a "florigen-like gene", and Ehd1 were up-regulated in HS112, whereas this up-regulation was not observed in the original variety of 'Gimbozu'. ChIP assays of the methylation states of histone H3 at lysine 4 (H3K4 revealed that the trimethylated H3K4 in the promoter region of the RFT1 chromatin was significantly increased in HS112. We conclude that Se14 is a novel photoperiod-sensitivity gene that has a suppressive effect on floral transition (flowering time under long day-length conditions through the modification of chromatin structure by H3K4me3 demethylation in the promoter region of RFT1.

  4. Hormone Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hormones quantified from marine mammal and sea turtle tissue provide information about the status of each animal sampled, including its sex, reproductive status and...

  5. Flowering Friendship Between Two Cities

    Institute of Scientific and Technical Information of China (English)

    Zhao; Zhengxu

    2015-01-01

    Xi’an of China and Chinju(Jinju)of the Republic of Korea are famous ancient capitals of their respective countries with a long history and culture heritage.It happens that both take the pomegranate flower as their symbol.In 2007,the"Spring of the Pomegranate Flower"—a friendly exchange program with folk cultural and art performances as the main focus

  6. Influence of night-breaks on flowering and phytohormones content in Hyoscyamus niger L.

    Directory of Open Access Journals (Sweden)

    Jan Kopcewicz

    2014-02-01

    Full Text Available Night-breaks caused both stimulated shoot growth and caused formation of flowers as well as a general increase in the content of phytohormones in leaves of the long-day plant Hyoscyamus niger L. At the time of flower formation in night-break treated plants, new gibberellin-like substances also appear. The results show that night-breaks cause similar changes in the phytohormones content as a long inductive photoperiod. It may be assumed that independently of the way of induction, the generative differentiation of long-day plants is always accompanied by a general increase in the amount of endogenous hormones and the appearance of new gibberellins. These results suggest the possibility of a morphogenetic role of hormones, especially gibberellins, in the phenomena of flower formation and differentiation.

  7. Phytochrome B regulates Heading date 1 (Hd1)-mediated expression of rice florigen Hd3a and critical day length in rice.

    Science.gov (United States)

    Ishikawa, Ryo; Aoki, Mayumi; Kurotani, Ken-Ichi; Yokoi, Shuji; Shinomura, Tomoko; Takano, Makoto; Shimamoto, Ko

    2011-06-01

    Many plants require circadian clock and light information for the photoperiodic control of flowering. In Arabidopsis, a long-day plant (LDP), flowering is triggered by the circadian clock-controlled expression of CONSTANS (CO) and light stabilization of the CO protein to induce FT (FLOWERING LOCUS T). In rice, a short-day plant (SDP), the CO ortholog Heading date 1 (Hd1) regulates FT ortholog Hd3a, but regulation of Hd3a by Hd1 differs from that in Arabidopsis. Here, we report that phytochrome B (phyB)-mediated suppression of Hd3a is a primary cause of long-day suppression of flowering in rice, based on the three complementary discoveries. First, overexpression of Hd1 causes a delay in flowering under SD conditions and this effect requires phyB, suggesting that light modulates Hd1 control of Hd3a transcription. Second, a single extension of day length decreases Hd3a expression proportionately with the length of daylight. Third, Hd1 protein levels in Hd1-overexpressing plants are not altered in the presence of light. These results also suggest that phyB-mediated suppression of Hd3a expression is a component of the molecular mechanism for critical day length in rice.

  8. Extensive transcriptome changes underlying the flower color intensity variation in Paeonia ostii

    Directory of Open Access Journals (Sweden)

    Lexuan eGao

    2016-01-01

    Full Text Available Tree peonies are a group of traditional ornamental plants, especially in East Asia, with Paeonia ostii as one of the most important ancestral species. P. ostii has flowers with varying colors, ranging from nearly white, light pink to deep pink. However, few studies have been done to unravel the molecular mechanisms underlying the flower color intensity variation in plants. Based on comparative analyses of the pigment composition and transcriptomes of P. ostii with different flower color intensities, we found that the anthocyanin concentration was significantly correlated with the flower color intensity in P. ostii. Transcriptome analysis by RNA-Sequencing revealed 7,187 genes that were differentially expressed between flowers with different color intensities. Functional enrichment analysis of differentially expressed genes revealed multiple pathways possibly responsible for color intensity variation in P. ostii, including flavonoid biosynthesis, fatty acid oxidation, carbohydrate metabolism and hormone-mediated signaling. Particularly, while anthocyanin biosynthesis genes showing positive correlations between their expression and anthocyanin concentration in flowers, two transcription factors, PoMYB2 and PoSPL1, seem to negatively regulate anthocyanin accumulation by affecting the activation capacity of the MYB-bHLH-WDR complex, exhibiting an inverse relationship between their expression and anthocyanin accumulation. Our results showed that, although anthocyanin biosynthesis had a direct effect on the pigmentation of the P. ostii flower, other metabolic and hormone-mediated signaling pathways were also contributed to the flower color intensity variation in P. ostii, suggesting complex coordinated changes in the transcriptional network. Differential expression of genes encoding anthocyanin repressors seems to be the major factor responsible for the intensity variation in anthocyanin pigmentation in P. ostii.

  9. Tolerance of edible flowers to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Amanda C.R.; Araujo, Michel M.; Costa, Helbert S.F.; Almeida, Mariana C.; Villavicencio, Anna Lucia C.H., E-mail: ackoike@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) Sao Paulo, SP (Brazil)

    2011-07-01

    People have been eating flowers and using them in culinary creations for hundreds of years. Edible flowers are increasingly being used in meals as an ingredient in salads or garnish, entrees, drinks and desserts. The irradiation process is an alternative method that can be used in disinfestation of food and flowers, using doses that do not damage the product. The sensitivity of flowers to irradiation varies from species to species. In the present research was irradiated with doses up to 1 kGy some edible flowers to examine their physical tolerance to gamma-rays. Furthermore, high doses gamma irradiation causes petal withering, browning process and injury in edible flowers. (author)

  10. Gibberellin hormone signal perception: down-regulating DELLA repressors of plant growth and development

    Science.gov (United States)

    The gibberellin (GA) hormone signal is perceived by a receptor with homology to hormone sensitive lipases, GID1 (GA-INSENSITIVE DWARF1). This leads to GA-stimulated responses including stem elongation, seed germination, and the transition to flowering. GA-binding enables GID1 to interact with and ...

  11. Hormone impostors

    Energy Technology Data Exchange (ETDEWEB)

    Colborn, T.; Dumanoski, D.; Myers, J.P.

    1997-01-01

    This article discusses the accumulating evidence that some synthetic chemicals disrupt hormones in one way or another. Some mimic estrogen and others interfere with other parts of the body`s control or endocrine system such as testosterone and thyroid metabolism. Included are PCBs, dioxins, furans, atrazine, DDT. Several short sidebars highlight areas where there are or have been particular problems.

  12. Identification of successive flowering phases highlights a new genetic control of the flowering pattern in strawberry

    Science.gov (United States)

    Perrotte, Justine; Guédon, Yann; Gaston, Amèlia; Denoyes, Béatrice

    2016-01-01

    The genetic control of the switch between seasonal and perpetual flowering has been deciphered in various perennial species. However, little is known about the genetic control of the dynamics of perpetual flowering, which changes abruptly at well-defined time instants during the growing season. Here, we characterize the perpetual flowering pattern and identify new genetic controls of this pattern in the cultivated strawberry. Twenty-one perpetual flowering strawberry genotypes were phenotyped at the macroscopic scale for their course of emergence of inflorescences and stolons during the growing season. A longitudinal analysis based on the segmentation of flowering rate profiles using multiple change-point models was conducted. The flowering pattern of perpetual flowering genotypes takes the form of three or four successive phases: an autumn-initiated flowering phase, a flowering pause, and a single stationary perpetual flowering phase or two perpetual flowering phases, the second one being more intense. The genetic control of flowering was analysed by quantitative trait locus mapping of flowering traits based on these flowering phases. We showed that the occurrence of a fourth phase of intense flowering is controlled by a newly identified locus, different from the locus FaPFRU, controlling the switch between seasonal and perpetual flowering behaviour. The role of this locus was validated by the analysis of data obtained previously during six consecutive years. PMID:27664957

  13. Identification of successive flowering phases highlights a new genetic control of the flowering pattern in strawberry.

    Science.gov (United States)

    Perrotte, Justine; Guédon, Yann; Gaston, Amèlia; Denoyes, Béatrice

    2016-10-01

    The genetic control of the switch between seasonal and perpetual flowering has been deciphered in various perennial species. However, little is known about the genetic control of the dynamics of perpetual flowering, which changes abruptly at well-defined time instants during the growing season. Here, we characterize the perpetual flowering pattern and identify new genetic controls of this pattern in the cultivated strawberry. Twenty-one perpetual flowering strawberry genotypes were phenotyped at the macroscopic scale for their course of emergence of inflorescences and stolons during the growing season. A longitudinal analysis based on the segmentation of flowering rate profiles using multiple change-point models was conducted. The flowering pattern of perpetual flowering genotypes takes the form of three or four successive phases: an autumn-initiated flowering phase, a flowering pause, and a single stationary perpetual flowering phase or two perpetual flowering phases, the second one being more intense. The genetic control of flowering was analysed by quantitative trait locus mapping of flowering traits based on these flowering phases. We showed that the occurrence of a fourth phase of intense flowering is controlled by a newly identified locus, different from the locus FaPFRU, controlling the switch between seasonal and perpetual flowering behaviour. The role of this locus was validated by the analysis of data obtained previously during six consecutive years.

  14. Spring Flowers: Harvest of a Sensitive Eye

    Science.gov (United States)

    Clark, Eloise; Levin, Ted

    1978-01-01

    Defining and describing a number of spring flowers, this article includes illustrations and explanations that demonstrate "art and science are born of the same parents". The flowers discussed are skunk cabbage, bellwort, spring beauty, jack-in-the-pulpit, Solomon's seal, wild geranium, showy orchids, moccasin flower, bluets, apple, and Indian…

  15. Notes on collecting flower-visiting insects

    NARCIS (Netherlands)

    Willemstein, S.C.

    1974-01-01

    Flower-visiting insects may play a role in the pollination of the flowers they visit. An important indication for this is the pollen they carry on their body. The transport of pollen does not prove pollination without observations of the behaviour of the insects on the flowers, but at least it offer

  16. Notes on collecting flower-visiting insects

    NARCIS (Netherlands)

    Willemstein, S.C.

    1974-01-01

    Flower-visiting insects may play a role in the pollination of the flowers they visit. An important indication for this is the pollen they carry on their body. The transport of pollen does not prove pollination without observations of the behaviour of the insects on the flowers, but at least it

  17. Flowering biology, nectar production and insect visits in Cucurbita pepo L. flowers

    Directory of Open Access Journals (Sweden)

    Marta Dmitruk

    2012-12-01

    Full Text Available In 1998-2000 studies on length and abundance of flowering and on nectar productivity of zucchini and marrow (Cucurbita pepo L. were carried out in Lublin area. Flowers visitors were also monitored. Flowering of plants lasted from the end of June till the end of September. The mean number of flowers per plant of zucchini reached: 31 (male flowers and 26 (female flowers, and for marrow 226 and 22, respectively. Flowers lived, on average, for 5 hours. Female flowers of marrow secreted the highest amount of nectar - 1.354 g per 10 flowers, on average. Sugar content in nectar was 21.84%-27.31%. The mean total amount of sugars secreted by 10 flowers of Cucurbita pepo L. was 21.5-304.3 mg. Pollinators were mainly bumblebees and honey bees.

  18. Flowers and Landscape by Serendipity.

    Science.gov (United States)

    Pippin, Sandi

    2003-01-01

    Describes an art lesson in which students sketch drawings of flowers and use watercolor paper and other materials to paint a landscape. Explains that the students also learn about impressionism in this lesson. Discusses how the students prepare the paper and create their artwork. (CMK)

  19. Beijing’s Flower Markets

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Whether you want to keep your green thumb in shape, bring Mother Nature into your apartment, or buy flowers for a special occasion, you will find everything you want and even more in Beijing’s specialized markets. here are some of the most popular and what they offer.

  20. Thrips (Thysanoptera) of coffee flowers

    Science.gov (United States)

    A survey of thrips (Thysanoptera) associated with coffee flowers was conducted in coffee plantations in Chiapas, Mexico. The main objectives were to identify them and to determine whether they were carrying coffee pollen grains. A total of 40 thrips species in 22 genera were identified. The most com...

  1. Variations of metabolites and proteome in Lonicera japonica Thunb. buds and flowers under UV radiation.

    Science.gov (United States)

    Zhu, Wei; Zheng, Wen; Hu, Xingjiang; Xu, Xiaobao; Zhang, Lin; Tian, Jingkui

    2017-04-01

    Lonicera japonica Thunb., also known as Jin Yin Hua and Japanese honeysuckle, is used as a herbal medicine in Asian countries. Its flowers have been used in folk medicine in the clinic and in making food or healthy beverages for over 1500years in China. To investigate the molecular processes involved in L. japonica development from buds to flowers exposed to UV radiation, a comparative proteomics analysis was performed. Fifty-four proteins were identified as differentially expressed, including 42 that had increased expression and 12 that had decreased expression. The levels of the proteins related to glycolysis, TCA/organic acid transformation, major carbohydrate metabolism, oxidative pentose phosphate, stress, secondary metabolism, hormone, and mitochondrial electron transport were increased during flower opening process after exposure to UV radiation. Six metabolites in L. japonica buds and flowers were identified and relatively quantified using LC-MS/MS. The antioxidant activity was performed using a 1,1-diphenyl-2-picrylhydrazyl assay, which revealed that L. japonica buds had more activity than the UV irradiated flowers. This suggests that UV-B radiation induces production of endogenous ethylene in L. japonica buds, thus facilitating blossoming of the buds and activating the antioxidant system. Additionally, the higher metabolite contents and antioxidant properties of L. japonica buds indicate that the L. japonica bud stage may be a more optimal time to harvest than the flower stage when using for medicinal properties.

  2. Sampling flower scent for chromatographic analysis.

    Science.gov (United States)

    Stashenko, Elena E; Martínez, Jairo René

    2008-06-01

    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.

  3. Flowering schedule in a perennial plant

    DEFF Research Database (Denmark)

    Ehrlén, Johan; Raabova, Jana; Dahlgren, Johan

    2015-01-01

    Optimal timing of reproduction within a season may be influenced by several abiotic and biotic factors. These factors sometimes affect different components of fitness, making assessments of net selection difficult. We used estimates of offspring fitness to examine how pre-dispersal seed predation...... influences selection on flowering schedule in an herb with a bimodal flowering pattern, Actaea spicata. Within individuals, seeds from flowers on early terminal inflorescences had a higher germination rate and produced larger seedlings than seeds from flowers on late basal inflorescences. Reproductive value......, estimated using demographic integral projection models and accounting for size-dependent differences in future performance, was two times higher for intact seeds from early flowers than for seeds from late flowers. Fruits from late flowers were, however, much more likely to escape seed predation than fruits...

  4. The effect of inductive photoperiod on flower formation and phytohormones level in a long day plant Hyoscyamus niger L.

    Directory of Open Access Journals (Sweden)

    J. Kopcewicz

    2015-05-01

    Full Text Available The anatomical and hormonal investigations on a long day plant Hyoscyamus niger L. during the time of the generative photoinduction have been conducted. The plants were grown during 75 days on a short photoperiod and then they were transferred to long day conditions. The earliest anatomical symptoms of flower initiation were noticed after four long photoperiods. The inductive photoperiod causes also a general increase in the amounts of phytohormones. During the flower evocation the intensive accumulation of cytokinins and gibberellins in leaves takes place. The post-inductive period, in which the development of flower elements happens, is characterized by changing amount of phytohormones. The content of hormonal substances is subjected to the rhytmical changes related to the periods of light and darknees in the twenty four hours' cycle.

  5. Efikasi Chitosan untuk Memperpanjang Flower Longevity Bunga Anggrek Dendrobium Hibrida dalam Pot (Potted Flower

    Directory of Open Access Journals (Sweden)

    I MADE SUKEWIJAYA

    2015-09-01

    Full Text Available Effication of Chitosan on Lengthening The Flower Longevity of Potted Orchid ofDendrobium Hybrid. The aim of the current research is to investigate general effects of Chitosantreatment on the flowering of Dendrobium orchid and to find out the optimum concentration of Chitosanin lengthening flower longevity of potted orchid of Dendrobium hybrid. Results of the research showedthat Chitosan application significantly affected variables of the number of flower per-plant, the length ofindividual flower, period of time to get full blooming, and the flower longevity. The best results for thoseof variables was achieved with Chitosan concentration of 0.15%.

  6. Flower colour adaptation in a mimetic orchid.

    Science.gov (United States)

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

    2012-06-22

    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.

  7. Ectopic expression of OsMADS45 activates the upstream genes Hd3a and RFT1 at an early development stage causing early flowering in rice.

    Science.gov (United States)

    Wang, Jiun-Da; Lo, Shuen-Fang; Li, Yan-Suan; Chen, Po-Ju; Lin, Shih-Yun; Ho, Teh-Yuan; Lin, Jenq-Horng; Chen, Liang-Jwu

    2013-12-01

    The rice gene, OsMADS45, which belongs to the MADS-box E class gene, participates in the regulation of floral development. Previous studies have revealed that ectopic expression of OsMADS45 induces early flowering and influences reduced plant height under short-day (SD) conditions. However, the regulation mechanism of OsMADS45 overexpression remains unknown. We introduce an OsMADS45 overexpression construct Ubi:OsMADS45 into TNG67 plants (an Hd1 (Heading date 1) and Ehd1 (Early heading date 1) defective rice cultivar grown in Taiwan), and we analyzed the expression patterns of various floral regulators to understand the regulation pathways affected by OsMADS45 expression. The transgenic rice exhibit a heading date approximately 40 days earlier than that observed in TNG67 plants, and transgenic rice display small plant size and low grain yield. OsMADS45 overexpression did not alter the oscillating rhythm of the examined floral regulatory genes but advanced (by approximately 20 days) the up-regulate of two florigens, Hd3a (Heading Date 3a) and RFT1 (RICE FLOWERING LOCUS T1) and suppressed the expression of Hd1 at the juvenile stage. The expression levels of OsMADS14 and OsMADS18, which are two well-known reproductive phase transition markers, were also increased at early developmental stages and are believed to be the major regulators responsible for early flowering in OsMADS45-overexpressing transgenic rice. OsMADS45 overexpression did not influence other floral regulator genes upstream of Hd1 and Ehd1, such as OsGI (OsGIGANTEA), Ehd2/Osld1/RID1 and OsMADS50. These results indicate that in transgenic rice, OsMADS45 overexpressing ectopically activates the upstream genes Hd3a and RFT1 at early development stage and up-regulates the expression of OsMADS14 and OsMADS18, which induces early flowering.

  8. Flower size and longevity influence florivory in the large-flowered shrub Cistus ladanifer

    Science.gov (United States)

    Teixido, Alberto L.; Méndez, Marcos; Valladares, Fernando

    2011-09-01

    Plants with larger and longer-lived flowers receive more pollinator visits and increase reproductive success, though may also suffer more from antagonistic interactions with animals. Florivores can reduce fruit and seed production, so selection on flower size, floral longevity and/or number of flowers may thus be determined by the relative effects of both pollinators and florivores. In this study flowers of Cistus ladanifer, a large-flowered Mediterranean shrub, were monitored to evaluate the effects of flower size, floral longevity and number of flowers on levels of florivory in four populations. Number of flowers was variable but did not differ among populations. Both flower size and floral longevity of C. ladanifer showed broad variation and significantly differed among populations. Overall, 7% of flowers suffered attack by florivores, which were mainly ants picking the stamens and beetles consuming petals and pollen. Within-populations, larger and longer-lived flowers tended to be affected by florivores more frequently. The low overall incidence of florivores and its lack of between-population variation suggest that florivory may not influence intraspecific variation of these floral traits. However, moderate florivory levels on the largest and longest-lived flowers open the possibility of exerting selection towards smaller and shorter-lived flowers in some of the populations studied.

  9. Flower, fruit phenology and flower traits in Cordia boissieri (Boraginaceae from northeastern Mexico

    Directory of Open Access Journals (Sweden)

    Cristian Adrian Martínez-Adriano

    2016-05-01

    Full Text Available We characterized variations in Cordia boissieri flowers and established if these variations occur between plants or between flowering events. Flowering and fruiting was measured for 256 plants. A GLM test was used to determine the relationship between flowering and fruit set processes and rainfall. We performed measurements of floral traits to detect variations within the population and between flowering events. The position of the anthers with respect to the ovary was determined in 1,500 flowers. Three out of four flowering events of >80% C. boissieri plants occurred after rainfall events. Only one flowering event occurred in a drought. Most plants flowered at least twice a year. The overlapping of flowering and fruiting only occurred after rainfall. Anthesis lasted three-to-five days, and there were two flower morphs. Half of the plants had longistylus and half had brevistylus flowers. Anacahuita flower in our study had 1–4 styles; 2–9 stamens; 6.5–41.5 mm long corolla; sepals from 4.5–29.5 mm in length; a total length from 15.5–59 mm; a corolla diameter from 10.5–77 mm. The nectar guide had a diameter from 5–30.5 mm; 4–9 lobes; and 5 distinguishable nectar guide colors. The highest variation of phenotypic expression was observed between plants.

  10. Main regulatory pathways, key genes and microRNAs involved in flower formation and development of moso bamboo (Phyllostachys edulis).

    Science.gov (United States)

    Ge, Wei; Zhang, Ying; Cheng, Zhanchao; Hou, Dan; Li, Xueping; Gao, Jian

    2017-01-01

    Moso bamboo is characterized by infrequent sexual reproduction and erratic flowering habit; however, the molecular biology of flower formation and development is not well studied in this species. We studied the molecular regulation mechanisms of moso bamboo development and flowering by selecting three key regulatory pathways: plant-pathogen interaction, plant hormone signal transduction and protein processing in endoplasmic reticulum at different stages of flowering in moso bamboo. We selected PheDof1, PheMADS14 and six microRNAs involved in the three pathways through KEGG pathway and cluster analysis. Subcellular localization, transcriptional activation, Western blotting, in situ hybridization and qRT-PCR were used to further investigate the expression patterns and regulatory roles of pivotal genes at different flower development stages. Differential expression patterns showed that PheDof1, PheMADS14 and six miRNAs may play vital regulatory roles in flower development and floral transition in moso bamboo. Our research paves way for further studies on metabolic regulatory networks and provides insight into the molecular regulation mechanisms of moso bamboo flowering and senescence.

  11. Growth hormone suppression test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003376.htm Growth hormone suppression test To use the sharing features on this page, please enable JavaScript. The growth hormone suppression test determines whether growth hormone production ...

  12. Growth hormone test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003706.htm Growth hormone test To use the sharing features on this page, please enable JavaScript. The growth hormone test measures the amount of growth hormone ...

  13. Hormone Replacement Therapy

    Science.gov (United States)

    ... before and during menopause, the levels of female hormones can go up and down. This can cause ... hot flashes and vaginal dryness. Some women take hormone replacement therapy (HRT), also called menopausal hormone therapy, ...

  14. Effects of flowering phenology and synchrony on the reproductive success of a long-flowering shrub

    OpenAIRE

    Rodríguez-Pérez, Javier; Traveset, Anna

    2016-01-01

    Flowering phenology and synchrony with biotic and abiotic resources are crucial traits determining the reproductive success in insect-pollinated plants. In seasonal climates, plants flowering for long periods should assure reproductive success when resources are more predictable. In this work, we evaluated the relationship between flowering phenology and synchrony and reproductive success in Hypericum balearicum, a shrub flowering all year round but mainly during spring and summer. We studied...

  15. New evidence: Why flowers self-fertilize?

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Studies on some Himalayan Sginger flowers have contributed novel empirical evidence to Charles Darwin's self-pollination theory, according to CAS researchers from the Xishuangbanna Tropical Botanical Garden.

  16. A Role for Auxin in Flower Development

    Institute of Scientific and Technical Information of China (English)

    Youfa Cheng; Yunde Zhao

    2007-01-01

    Auxin has long been implicated in many aspects of plant growth and development including flower development. However, the exact roles of auxin in flower development have not been well defined until the recent identification of auxin biosynthesis mutants. Auxin is necessary for the initiation of floral primordia,and the disruption of auxin biosynthesis, polar auxin transport or auxin signaling leads to the failure of flower formation. Auxin also plays an essential role in specifying the number and identity of floral organs.Further analysis of the relationship between the auxin pathways and the known flower development genes will provide critical information regarding mechanisms of organogenesis and pattern formation in plants.

  17. RNA-seq analysis of apical meristem reveals integrative regulatory network of ROS and chilling potentially related to flowering in Litchi chinensis.

    Science.gov (United States)

    Lu, Xingyu; Li, Jingjing; Chen, Houbin; Hu, Jiaqi; Liu, Pengxu; Zhou, Biyan

    2017-08-31

    Litchi is an important woody fruit tree. Floral initiation in litchi is triggered by low temperatures. However, defective flowering is a major challenge for litchi production in times of climate change and global warming. Previous studies have shown that the reactive oxygen species (ROS) generated by methyl viologen dichloride hydrate (MV) promotes flowering. In this study, potted trees were transferred to growth chambers for low-temperature (LT), medium-temperature (MT), and high-temperature (HT) treatments. Trees at MT were subjected to ROS treatment to promote flowering, and those at LT were induced to flower. RNA-sequencing was applied to obtain a global transcriptome of the apical meristem and reveal potential gene networks controlling the transformation from vegetative meristems (VM) into inflorescence meristems (IM). We assembled 73,117 unigenes with a mean size of 790 bp and 11741 unigenes were identified as both chilling and ROS responsive genes (CRRGs), of which 48 were identified as flowering-related CRRGs, 59 were plant hormone signal transduction CRRGs, and 146 were plant hormone biosynthesis-related CRRGs. Genes co-expression network analysis indicated inner relationships, suggesting that ROS and chilling promotes the VM to IM transition through a regulatory gene network of transcription factors, hormones, and flowering regulators.

  18. Exploitation of Wild Flowers and the Sustainable Development of Flowers Industry in China

    Institute of Scientific and Technical Information of China (English)

    HONG Li; PANG Songling; ZHUO Lihuan

    2008-01-01

    This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development.

  19. Effect of Various Management Methods of Apical Flower Bud on Cut Flower Quality in Three Cultivars of Greenhouse Roses

    Directory of Open Access Journals (Sweden)

    mansour matloobi

    2017-02-01

    , it was determined in Rosa hybrida ‘Fire and Ice’ that the rate of increase in stem length was about two times more than that in ‘Kardinal’ cultivar when both compared to control cultivar. These differences may have genetic and/or environmental origins. Methods of stem treatment significantly affected some shoot characteristics such as bud burst time, number and weight of growing shoots on bent stems and flower diameter, but no significant effect was observed on most important marketable traits. However, this factor interacted significantly with cultivar in some characteristics such as time of bud burst and the number of growing shoots on bent stems, showing that similar stem treatments can cause different results in different cultivars. Methods of stem treatment unexpectedly did not change the stem marketable qualities such as stem length and diameter, while it significantly altered time of bud burst, flower diameter and weight of shoot sprouts on bent stems. The most interesting result was that time of bud burst decreased from about 10 days in the immediate stem bending with intact bud to about 5 days in the treatment containing bending practice two weeks after the flower bud removal. This feature can be valuable, since it can decrease time of shoot growth and harvest time, thereby increasing stem production per time scale. The highest weight of shoot sprouts on bent stems obtained when bud removal performed at bending time, indicating that this phenomenon occurs as a consequence of apical dominance removal. Growers can adjust leaf area per plant by controlling the rate of bud growth with or without the number of bud sprouts on the bent stems through implementing different flower shoot management systems. It was reported in many studies that altering stem position, removing flower bud, defoliating and practicing similar activities can change hormone and carbohydrate balance inside the plant, which, in turn, may lead to new shape of plant canopy with

  20. Comparative genomic analysis of soybean flowering genes.

    Directory of Open Access Journals (Sweden)

    Chol-Hee Jung

    Full Text Available 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

  1. Scent glands in legume flowers.

    Science.gov (United States)

    Marinho, C R; Souza, C D; Barros, T C; Teixeira, S P

    2014-01-01

    Scent glands, or osmophores, are predominantly floral secretory structures that secrete volatile substances during anthesis, and therefore act in interactions with pollinators. The Leguminosae family, despite being the third largest angiosperm family, with a wide geographical distribution and diversity of habits, morphology and pollinators, has been ignored with respect to these glands. Thus, we localised and characterised the sites of fragrance production and release in flowers of legumes, in which scent plays an important role in pollination, and also tested whether there are relationships between the structure of the scent gland and the pollinator habit: diurnal or nocturnal. Flowers in pre-anthesis and anthesis of 12 legume species were collected and analysed using immersion in neutral red, olfactory tests and anatomical studies (light and scanning electron microscopy). The main production site of floral scent is the perianth, especially the petals. The scent glands are distributed in a restricted way in Caesalpinia pulcherrima, Anadenanthera peregrina, Inga edulis and Parkia pendula, constituting mesophilic osmophores, and in a diffuse way in Bauhinia rufa, Hymenaea courbaril, Erythrostemon gilliesii, Poincianella pluviosa, Pterodon pubescens, Platycyamus regnellii, Mucuna urens and Tipuana tipu. The glands are comprised of cells of the epidermis and mesophyll that secrete mainly terpenes, nitrogen compounds and phenols. Relationships between the presence of osmophores and type of anthesis (diurnal and nocturnal) and the pollinator were not found. Our data on scent glands in Leguminosae are original and detail the type of diffuse release, which has been very poorly studied.

  2. Sexual dimorphism in flowering plants.

    Science.gov (United States)

    Barrett, Spencer C H; Hough, Josh

    2013-01-01

    Among dioecious flowering plants, females and males often differ in a range of morphological, physiological, and life-history traits. This is referred to as sexual dimorphism, and understanding why it occurs is a central question in evolutionary biology. Our review documents a range of sexually dimorphic traits in angiosperm species, discusses their ecological consequences, and details the genetic and evolutionary processes that drive divergence between female and male phenotypes. We consider why sexual dimorphism in plants is generally less well developed than in many animal groups, and also the importance of sexual and natural selection in contributing to differences between the sexes. Many sexually dimorphic characters, including both vegetative and flowering traits, are associated with differences in the costs of reproduction, which are usually greater in females, particularly in longer-lived species. These differences can influence the frequency and distribution of females and males across resource gradients and within heterogeneous environments, causing niche differences and the spatial segregation of the sexes. The interplay between sex-specific adaptation and the breakdown of between-sex genetic correlations allows for the independent evolution of female and male traits, and this is influenced in some species by the presence of sex chromosomes. We conclude by providing suggestions for future work on sexual dimorphism in plants, including investigations of the ecological and genetic basis of intraspecific variation, and genetic mapping and expression studies aimed at understanding the genetic architecture of sexually dimorphic trait variation.

  3. Fertilization Mechanisms in Flowering Plants.

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M

    2016-02-08

    Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals.

  4. Fertilization Mechanisms in Flowering Plants

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M.

    2016-01-01

    Compared to the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells they interact and fuse with two dimorphic female gametes (egg and central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca2+ is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes including mammals. PMID:26859271

  5. Air in xylem vessels of cut flowers

    NARCIS (Netherlands)

    Nijsse, J.; Meeteren, van U.; Keijzer, C.J.

    2000-01-01

    Until now all studies on the role of air emboli in the water uptake of cut flowers describe indirect methods to demonstrate the presencFe of air in the plant tissues. Using cut chrysanthemum flowers, this report is the first one that directly visualises both air and water in xylem ducts of cut

  6. Postharvest: Cut flowers and potted plants

    Science.gov (United States)

    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. ...

  7. Flower development of Begonia franconis Liebm

    NARCIS (Netherlands)

    Berghoef, J.

    1979-01-01

    Chapter 1The effects of growth-regulating substances and environmental conditions on the composition of Begonia franconis Liebm. inflorescences were analysed. The inflorescences are generally composed of two male flowers and one terminal female flower.Auxins, gibberellins, and cytokinins, added to t

  8. An Environmental Approach to Positive Emotion: Flowers

    Directory of Open Access Journals (Sweden)

    Jeannette Haviland-Jones

    2005-01-01

    Full Text Available For more than 5000 years, people have cultivated flowers although there is no known reward for this costly behavior. In three different studies we show that flowers are a powerful positive emotion “inducer”. In Study 1, flowers, upon presentation to women, always elicited the Duchenne or true smile. Women who received flowers reported more positive moods 3 days later. In Study 2, a flower given to men or women in an elevator elicited more positive social behavior than other stimuli. In Study 3, flowers presented to elderly participants (55+ age elicited positive mood reports and improved episodic memory. Flowers have immediate and long-term effects on emotional reactions, mood, social behaviors and even memory for both males and females. There is little existing theory in any discipline that explains these findings. We suggest that cultivated flowers are rewarding because they have evolved to rapidly induce positive emotion in humans, just as other plants have evolved to induce varying behavioral responses in a wide variety of species leading to the dispersal or propagation of the plants.

  9. Flower development of Begonia franconis Liebm.

    NARCIS (Netherlands)

    Berghoef, J.

    1979-01-01

    Chapter 1

    The effects of growth-regulating substances and environmental conditions on the composition of Begonia franconis Liebm. inflorescences were analysed. The inflorescences are generally composed of two male flowers and one terminal female flower.

    Auxins,

  10. Presence of two types of flowers with respect to nectar sugar in two gregariously flowering species

    Indian Academy of Sciences (India)

    Chaitali Anand; Chaitrali Umranikar; Pooja Shintre; Anuja Damle; Janhavi Kale; Jahnavi Joshi; Milind Watve

    2007-06-01

    Many species of animal-pollinated flowers are known to vary widely in the nectar content of flowers. Some proportion of flowers in many species is apparently nectarless, and such flowers are believed to be ‘cheaters’. Cheating may explain a part of the variability in nectar content. If cheating exists as a qualitatively different strategy then we expect bimodality in the distribution of nectar content of flowers. It has been shown in a multispecies study that gregarious species have a higher proportion of cheater flowers. We studied the frequency distribution of total nectar sugar in two gregariously flowering species Lantana camara and Utricularia purpurascens, which differed in other floral and ecological characters. At the population level, both the species showed significant bimodality in the total sugar content of flowers. The obvious sources of heterogeneity in the data did not explain bimodality. In Lantana camara, bimodality was observed within flowers of some of the individual plants sampled. In Utricularia purpurascens the proportion of nectarless flowers was more in high-density patches, suggesting that the gregariousness hypothesis may work within a species as well. The results support the hypothesis of cheating as a distinct strategy since two distinct types of flowers were observed in both the species. The effect of density in Utricularia purpurascens also supports the gregariousness hypothesis.

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

    Science.gov (United States)

    Munguía-Rosas, Miguel A; Ollerton, Jeff; Parra-Tabla, Victor; De-Nova, J Arturo

    2011-05-01

    Flowering times of plants are important life-history components and it has previously been hypothesized that flowering phenologies may be currently subject to natural selection or be selectively neutral. In this study we reviewed the evidence for phenotypic selection acting on flowering phenology using ordinary and phylogenetic meta-analysis. Phenotypic selection exists when a phenotypic trait co-varies with fitness; therefore, we looked for studies reporting an association between two components of flowering phenology (flowering time or flowering synchrony) with fitness. Data sets comprising 87 and 18 plant species were then used to assess the incidence and strength of phenotypic selection on flowering time and flowering synchrony, respectively. The influence of dependence on pollinators, the duration of the reproductive event, latitude and plant longevity as moderators of selection were also explored. Our results suggest that selection favours early flowering plants, but the strength of selection is influenced by latitude, with selection being stronger in temperate environments. However, there is no consistent pattern of selection on flowering synchrony. Our study demonstrates that phenotypic selection on flowering time is consistent and relatively strong, in contrast to previous hypotheses of selective neutrality, and has implications for the evolution of temperate floras under global climate change. © 2011 Blackwell Publishing Ltd/CNRS.

  12. Hormones and absence epilepsy

    NARCIS (Netherlands)

    Luijtelaar, E.L.J.M. van; Tolmacheva, E.A.; Budziszewska, B.

    2017-01-01

    Hormones have an extremely large impact on seizures and epilepsy. Stress and stress hormones are known to reinforce seizure expression, and gonadal hormones affect the number of seizures and even the seizure type. Moreover, hormonal concentrations change drastically over an individual's lifetime, es

  13. Hormones and absence epilepsy

    NARCIS (Netherlands)

    Luijtelaar, E.L.J.M. van; Budziszewska, B.; Tolmacheva, E.A.

    2009-01-01

    Hormones have an extremely large impact on seizures and epilepsy. Stress and stress hormones are known to reinforce seizure expression, and gonadal hormones affect the number of seizures and even the seizure type. Moreover, hormonal concentrations change drastically over an individual's lifetime, es

  14. Genetic markers for flowering in perennial ryegrass

    DEFF Research Database (Denmark)

    Paina, Cristiana; Byrne, Stephen; Andersen, Jeppe Reitan

    2011-01-01

    genes will be converted to molecular markers and mapped in an existing mapping population previously characterized for flowering time and vernalization response. References: Amasino, R.M., Michaels S.D. (2010). The Timing of Flowering. Plant Physiology 154: 516–520 Greenup, A., W. Peacock, W.J., Dennis...... E.S., Trevaskis, B. (2009). The molecular biology of seasonal flowering-responses in Arabidopsis and the cereals. Annals of Botany 103: 1165–1172 Distelfeld, A.,Li, C., Dubcovsky J. (2009). Regulation of flowering in temperate cereals. Current Opinion in Plant Biology 12:178–184 Jung, C., Müller, A.......E. (2009). Flowering time control and applications in plant breeding. Trends in Plant Science 14 /10: 563-573 Andersen, J.L., Jensen, L.B., Asp, T., Lübberstedt, T. (2006). Vernalization response in perennial ryegrass (Lolium perenne L.) involves orthologues of diploid wheat (Triticum monococcum) VRN1...

  15. The Variation of Oncidium Rosy Sunset Flower Volatiles with Daily Rhythm, Flowering Period, and Flower Parts

    Directory of Open Access Journals (Sweden)

    Yi-Tien Chiu

    2017-09-01

    Full Text Available Oncidium is an important ornamental crop worldwide, and in recent years, the characteristics of the flower aroma have become a concern for breeders. This study used headspace solid-phase microextraction (HS-SPME and gas chromatography/mass spectrometry (GC-MS analysis of the volatile compounds to study the aroma characteristics of Onc. Rosy Sunset. A total of 45 compounds were identified, with the major compound being linalool. Onc. Rosy Sunset had the highest odor concentration from 10:00 to 12:00 and lowest from 20:00 to 24:00. The inflorescence emitted the highest quantities of volatile compounds during stages 3–6, which then decreased with the aging of the flowers. In Onc. Rosy Sunset, the sepals and petals were the major parts for the floral fragrance emission, in which linalool content was the highest, whereas the lip and column had a different composition of major volatile compounds, of which benzaldehyde, β-myrcene, and β-caryophyllene dominated.

  16. Flowering phenology in subalpine meadows: does climate variation influence community co-flowering patterns?

    Science.gov (United States)

    Forrest, Jessica; Inouye, David W; Thomson, James D

    2010-02-01

    Climate change is expected to alter patterns of species co-occurrence, in both space and time. Species-specific shifts in reproductive phenology may alter the assemblages of plant species in flower at any given time during the growing season. Temporal overlap in the flowering periods (co-flowering) of animal-pollinated species may influence reproductive success if competitive or facilitative interactions between plant species affect pollinator services. We used a 33-year data set on flowering phenology in subalpine meadows in Colorado, USA, to determine whether interannual variation in snowmelt date, which marks the start of the growing season, affected co-flowering patterns. For two of four species considered, we found a significant relationship between snowmelt timing and composition of the assemblage of co-flowering plants. In years of early snowmelt, Lathyrus lanszwertii var. leucanthus (Fabaceae), the species we investigated in most detail, tended to overlap with earlier-flowering species and with fewer species overall. In particular, overlap with the flowering period of Lupinus polyphyllus var. prunophilus, with which Lathyrus leucanthus shares pollinators, was significantly reduced in early-snowmelt years. The observed association between timing of snowmelt and patterns of flowering overlap could not have been predicted simply by examining temporal trends in the dates of peak flowering of the dominant species in the community, as peak flowering dates have largely shifted in parallel with respect to snowmelt date. However, subtle interspecific differences in responsiveness of flowering time, duration, and intensity to interannual climate variation have likely contributed to the observed relationship. Although much of the year-to-year variation in flowering overlap remains unexplained by snowmelt date, our finding of a measurable signal of climate variation suggests that future climate change may lead to altered competitive environments for these wildflower

  17. Standardization of hormone determinations.

    Science.gov (United States)

    Stenman, Ulf-Håkan

    2013-12-01

    Standardization of hormone determinations is important because it simplifies interpretation of results and facilitates the use of common reference values for different assays. Progress in standardization has been achieved through the introduction of more homogeneous hormone standards for peptide and protein hormones. However, many automated methods for determinations of steroid hormones do not provide satisfactory result. Isotope dilution-mass spectrometry (ID-MS) has been used to establish reference methods for steroid hormone determinations and is now increasingly used for routine determinations of steroids and other low molecular weight compounds. Reference methods for protein hormones based on MS are being developed and these promise to improve standardization.

  18. Flower Power at the Dutch Flower Auctions? Application of an Inverse Almost Ideal Demand System

    OpenAIRE

    Steen, Marie

    2006-01-01

    Information on price-quantity relationships will enable flower producers to reduce risk and raise profits through better timing of rotations as well as better utilization of limited greenhouse space. The present paper presents econometric evidence on such price-quantity relationships for major species of cut flowers at the Dutch flower auctions. Specifically, an inverse linear approximate almost ideal demand model with seasonal adjustments is applied. This paper is introducing trigonometric f...

  19. INDUCTION OF CALLUS FORMATION FROM DIFFERENT PARTS OF Citrus grandis (OSBECK FLOWERS

    Directory of Open Access Journals (Sweden)

    Zarina Binti Zakaria

    2010-01-01

    Full Text Available The objectives of the present work were to study the capability of pomelo's floral tissues to produce callus and to investigate the influence of plant growth regulators on callus induction and development. Various parts of flower namely petal, sepal, style, ovary, pistil and cup base were cultured onto Murashige and Skoog (MS basal medium supplemented with different levels of 2,4-dichlorophenoxyacetic acid (2,4-D, 6-benzylaminopurine (BAP and 6-Furfurylaminopurine (kinetin. It was found that different parts of flowers favored different levels of hormone for callus induction. The highest formation of callus were obtained from petal and sepal cultured on MS media supplemented with 1.5 mg/l kinetin. A 50 ± 2.3%explants from style and pistil had initiated callus when cultured on MS media supplemented with 0.05 mg/l and 0.10 mg/l BAP, respectively. On the other hand, sucrose agar (SA media alone had managed to induce callus formation from almost every part of the flowers with a success rate between 7.69 ± 0.32 to 50 ± 3.18%. The uncut part of flowers initiated high percentage of callus (14.6 ± 0.35% as shown in the study on petal.

  20. "Say it...near the flower shop": further evidence of the effect of flowers on mating.

    Science.gov (United States)

    Guéguen, Nicolas

    2012-01-01

    For millennia, flowers have been used to convey romance. In this study, 18-25-year-old women (N = 600) walking alone in a shopping mall were approached by an attractive 20-year-old male-confederate who solicited them for their phone number. The women were solicited as they were walking in the area of a flower shop, a cake shop, or a women's shoes shop. It was found that women agreed more favorably to the confederate's courtship solicitation when solicited in the area of the flower shop. Positive mood induced by exposure to flowers was used to explain these results.

  1. Flower solid modeling based on sketches

    Institute of Scientific and Technical Information of China (English)

    Zhan DING; Shu-chang XU; Xiu-zi YE; Yin ZHANG; San-yuan ZHANG

    2008-01-01

    In this paper we propose a method to model flowers of solid shape. Based on (Ijiri et al., 2005)'s method, we separate individual flower modeling and inflorescence modeling procedures into structure and geometry modeling. We incorporate interactive editing gestures to allow the user to edit structure parameters freely onto structure diagram. Furthermore, we use free-hand sketching techniques to allow users to create and edit 3D geometrical elements freely and easily. The final step is to automatically merge all independent 3D geometrical elements into a single waterproof mesh. Our experiments show that this solid modeling approach is promising. Using our approach, novice users can create vivid flower models easily and freely. The generated flower model is waterproof. It can have applications in visualization, animation, gaming, and toys and decorations if printed out on 3D rapid prototyping devices.

  2. Flowers of annonaceae: Morphology, classification, and evolution

    NARCIS (Netherlands)

    Heusden, van E.C.H.

    1992-01-01

    The present paper describes the diversity in floral characters of Annonaceae and their distribution over the family, and discusses their value for classification and generic delimitation. Flower morphology predominated historical classifications of this family since Hooker & Thomson (1855)

  3. Endothermy by flowers of Rhizanthes lowii (Rafflesiaceae).

    Science.gov (United States)

    Patiño, S; Grace, J; Bänziger, H

    2000-08-01

    Rhizanthes lowii (Beccari) Harms (Rafflesia- ceae) is a parasitic plant that grows in the understory of the rainforest in South-East Asia. This plant does not have leaves, stems, or photosynthetic tissue and is characterised by the emission of a strong odour that attracts the natural pollinators, carrion flies. Flowers that volatilise odorous compounds and attract carrion flies, beetles and other insects are often thermogenic. Here we present evidence of both thermogenesis and thermoregulation in R. lowii from microclimate and tissue temperatures measured during different stages of flower development in R. lowii, in natural conditions in Brunei, Borneo. Endothermy was detected in young and mature buds as well as in blooming flowers and even in decaying tissues 3 or more days after blooming. Tissue temperatures were maintained at 7-9 K above air temperature, in both female and male flowers, at all stages of floral development.

  4. The evolutionary root of flowering plants.

    Science.gov (United States)

    Goremykin, Vadim V; Nikiforova, Svetlana V; Biggs, Patrick J; Zhong, Bojian; Delange, Peter; Martin, William; Woetzel, Stefan; Atherton, Robin A; McLenachan, Patricia A; Lockhart, Peter J

    2013-01-01

    Correct rooting of the angiosperm radiation is both challenging and necessary for understanding the origins and evolution of physiological and phenotypic traits in flowering plants. The problem is known to be difficult due to the large genetic distance separating flowering plants from other seed plants and the sparse taxon sampling among basal angiosperms. Here, we provide further evidence for concern over substitution model misspecification in analyses of chloroplast DNA sequences. We show that support for Amborella as the sole representative of the most basal angiosperm lineage is founded on sequence site patterns poorly described by time-reversible substitution models. Improving the fit between sequence data and substitution model identifies Trithuria, Nymphaeaceae, and Amborella as surviving relatives of the most basal lineage of flowering plants. This finding indicates that aquatic and herbaceous species dominate the earliest extant lineage of flowering plants. [; ; ; ; ; .].

  5. USING BACH FLOWER IN HOLISTIC PSYCHOTHERAPY

    Directory of Open Access Journals (Sweden)

    Vagner Ferreira do Nascimento

    2017-05-01

    Full Text Available This is a narrative review from scientific literature that aimed to describe concepts and approaches for indications of the therapeutic use of Bach flower remedies in holistic psychotherapy. The review was developed in February 2016 from books, official documents and articles indexed in Lilacs and Scielo databases. Bach flower remedies is a therapeutic method that aims to restore the balance of human being, restoring its vital energy through holistic care. Because the flower essences act on psychic and emotional dimension of individual, when employed in holistic psychotherapy can provide greater autonomy, self-care and effectiveness compared to other alternative methods. The literature indicated that flower essence therapy is a safe practice and can be used in a complementary to health care, but should be performed by qualified professionals. It has also shown to be a promising and important area for nursing professional, but it still requires greater investment in research in the area to support the practice.

  6. Bioidentical Hormones and Menopause

    Science.gov (United States)

    ... Hormones and Menopause Fact Sheet Bioidentical Hormones and Menopause January, 2012 Download PDFs English Espanol Editors Howard ... JoAnn Pinkerton, MD Richard Santen, MD What is menopause? Menopause is the time of life when monthly ...

  7. Growth hormone deficiency

    Science.gov (United States)

    ... dosage of the medicine. Serious side effects of growth hormone treatment are rare. Common side effects include: Headache Fluid ... years. The rate of growth then slowly decreases. Growth hormone therapy does not work for all children. Left untreated, ...

  8. Hormones and Obesity

    Science.gov (United States)

    ... Balance › Hormones and Obesity Fact Sheet Hormones and Obesity March, 2010 Download PDFs English Espanol Editors Caroline Apovian, MD Judith Korner, MD, PhD What is obesity? Obesity is a chronic (long-term) medical problem ...

  9. Ecological adaptations of Hypocyrta glabra Hook. flowers

    Directory of Open Access Journals (Sweden)

    Mychajło Czernećkyj

    2012-12-01

    Full Text Available The research on the blooming ecology and the flower morphology of Hypocyrta glabra Hook. (Gesneriaceae cultivated in laboratories and outdoors have been carried out. The life span of flowers and morphological changes in successive phases of the blooming period have been observed. The H. glabra flowers are protandrous and the stamens translocate during the flowering process. The macro- and microstructure of calyx, corolla, androecium, gynoecium and nectaries have been analyzed. The size, shape and viability of pollen grains have been designated and their number per stamen head has been calculated. The location of nectaries in H. glabra flowers has suggested that they stem from the 5th stamen during phylogenesis. It has been proved that the nectaries are provided by numerous vascular bundles and that the nectar is secreted by stomata. The stomatal field comprises 2/5 of nectary height and is situated on the abaxial side of the apix part. The average number of stomata is 63.2 per 1 mm2. The average amount of nectar produced by 10 flowers in their fourth day of life reached 223.7 mg. The sugar concentration was 32.7%. Numerous glandular and non-glandular trichomes have been noticed on the surface of calyx, corolla and gynoecium, which indicate the xeromorphic adaptation of the flower. It has been observed that the numbers of glandular and non-glandular trichomes per unit of the external surface of corolla are similar. Outdoors the secretion produced by calyx and corolla glands was willingly collected by wasps. It seems that such features of H. glabra flowers as position, shape and colour of corolla, the abundance of the nectar and pollen produced are connected with their adaptation to pollination by humming-birds in the species natural environment.

  10. Integrating two patterning processes in the flower. (refereed by Editor) Addendum to: Simulation of organ patterning on the floral meristem using a polar auxin transport model.

    NARCIS (Netherlands)

    Mourik, van S.; Kaufmann, K.; Dijk, van A.D.J.; Angenent, G.C.; Merks, R.M.H.; Molenaar, J.

    2012-01-01

    Spatial organ arrangement plays an important role in flower development. The position and the identity of floral organs is influenced by various processes, in particular the expression of MADS-box transcription factors for identity and dynamics of the plant hormone auxin for positioning. We are curr

  11. Phytohormones level in the leaves of Hyoscyamus niger L. during variable photoperiods at the time of flower initiation and differentiation

    Directory of Open Access Journals (Sweden)

    Jan Kopcewicz

    2014-02-01

    Full Text Available The investigations concern changes in the content of endogenous phytohormones in the leaves of the long-day plant Hyoscyamus niger L. during variable photoperiods applied before and after flower initiation. The results show that alternation of inductive photoperiods with short days leads to quantitative changes in the content of phytohormones. The changeable photoperiod leads to a general decrease in the contents of gibberellins, cytokinins and auxins during the short noninductive days both before and after flower initiation. Alternation of the inductive photoperiod with short days does not influence the content of abscisic acid-like substances before flower initiation and causes an increase of the amount of inhibitors in the postinductive period. The content of hormonal substances is subjected to rhytmical changes related to the periods of light and darkness in the twenty-four hours' cycle.

  12. Synchrony in the phenology of a culturally iconic spring flower.

    Science.gov (United States)

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

    2012-03-01

    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.

  13. Synchrony in the phenology of a culturally iconic spring flower

    Science.gov (United States)

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

    2012-03-01

    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.

  14. Research on the Molecular Mechanism of Florigen in Rice%水稻成花素分子作用机制研究进展

    Institute of Scientific and Technical Information of China (English)

    徐千惠; 张大兵; 梁婉琪

    2010-01-01

    植物开花时间是植物适应不同自然环境的重要生物学特性.近年来模式双子叶长日植物拟南芥中的研究结果表明拟南芥的开花时间受到光周期途径、春化途径、自主途径和赤霉素途径的调节,成花素FT(FLOWERING LOCUS T)是这些调控途径最重要的整合因子之一.水稻是典型的单子叶模式短日植物,水稻中Hd3a(HEADING DATE 3a)是拟南芥FT的同源基因,它的表达产物即是水稻的成花素,可以从叶片移动到顶端分生组织,促进开花.虽然FT和Hd3a在拟南芥和水稻中的功能和序列高度保守,但通过对水稻中其它开花控制基因的研究表明,水稻Hd3a的上游调控因子和调控机制和拟南芥存在很大差异.本文对目前关于水稻成花素Hd3a及其表达调控的研究进展进行综述,为进一步研究Hd3a基因的作用机制提供参考.

  15. Pollination Services of Mango Flower Pollinators.

    Science.gov (United States)

    Huda, A Nurul; Salmah, M R Che; Hassan, A Abu; Hamdan, A; Razak, M N Abdul

    2015-01-01

    Measuring wild pollinator services in agricultural production is very important in the context of sustainable management. In this study, we estimated the contribution of native pollinators to mango fruit set production of two mango cultivars Mangifera indica (L). cv. 'Sala' and 'Chok Anan'. Visitation rates of pollinators on mango flowers and number of pollen grains adhering to their bodies determined pollinator efficiency for reproductive success of the crop. Chok Anan failed to produce any fruit set in the absence of pollinators. In natural condition, we found that Sala produced 4.8% fruit set per hermaphrodite flower while Chok Anan produced 3.1% per flower. Hand pollination tremendously increased fruit set of naturally pollinated flower for Sala (>100%), but only 33% for Chok Anan. Pollinator contribution to mango fruit set was estimated at 53% of total fruit set production. Our results highlighted the importance of insect pollinations in mango production. Large size flies Eristalinus spp. and Chrysomya spp. were found to be effective pollen carriers and visited more mango flowers compared with other flower visitors. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

  16. Phytochrome, plant growth and flowering

    Science.gov (United States)

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

    1994-01-01

    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.

  17. Trees as huge flowers and flowers as oversized floral guides: the role of floral color change and retention of old flowers in Tibouchina pulchra

    Directory of Open Access Journals (Sweden)

    Vinícius Lourenço Garcia Brito

    2015-05-01

    Full Text Available Floral color changes and retention of old flowers are frequently combined phenomena restricted to the floral guide or single flowers in few-flowered inflorescences. They are thought to increase the attractiveness over long distances and to direct nearby pollinators towards the rewarding flowers. In Tibouchina pulchra, a massively flowering tree, the whole flower changes its color during anthesis. On the first day, the flowers are white and on the next three days, they change to pink. This creates a new large-scale color pattern in which the white pre-changed flowers contrast against the pink post-changed ones over the entire tree. We describe the spectral characteristics of floral colors of T. pulchra and test bumblebees´ response to this color pattern when viewed at different angles (simulating long and short distances. The results indicated the role of different color components in bumblebee attraction and the possible scenario in which this flower color pattern has evolved. We tested bumblebees´ preference for simulated trees with 75% pink and 25% white flowers resembling the color patterns of T. pulchra, and trees with green leaves and pink flowers (control in long-distance approach. We also compared an artificial setting with three pink flowers and one white flower (T. pulchra model against four pink flowers with white floral guides (control in short-distance approach. Bumblebees spontaneously preferred the simulated T. pulchra patterns in both approaches despite similar rewards. Moreover, in short distances, pollinator visits to peripheral, non-rewarding flowers occurred only half as frequently in the simulated T. pulchra when compared to the control. Thefore, this exceptional floral color change and the retention of old flowers in T. pulchra favors the attraction of pollinators over long distances in a deception process while it honestly directs them towards the rewarding flowers at short distances possibly exploring their innate color

  18. Strawberry homologue of terminal flower1 integrates photoperiod and temperature signals to inhibit flowering.

    Science.gov (United States)

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

    2015-04-01

    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.

  19. To flower or not to flower, a temperature-sensitive decision. Characterization of flowering responses at high ambient temperature in Arabidopsis thaliana

    NARCIS (Netherlands)

    Rodenburg, N.

    2015-01-01

    To maximize fitness, plants use environmental cues to optimize growth processes. One of the processes under strong environmental regulation is flowering. Multiple environmental factors influence flowering, including temperature. Both a continuously increased ambient temperature as well as temporary

  20. To flower or not to flower, a temperature-sensitive decision : Characterization of flowering responses at high ambient temperature in Arabidopsis thaliana

    NARCIS (Netherlands)

    Rodenburg, Nicole

    2015-01-01

    To maximize fitness, plants use environmental cues to optimize growth processes. One of the processes under strong environmental regulation is flowering. Multiple environmental factors influence flowering, including temperature. Both a continuously increased ambient temperature as well as temporary

  1. Genetic analyses of interactions among gibberellin, abscisic acid, and brassinosteroids in the control of flowering time in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Malgorzata A Domagalska

    Full Text Available BACKGROUND: Genetic interactions between phytohormones in the control of flowering time in Arabidopsis thaliana have not been extensively studied. Three phytohormones have been individually connected to the floral-timing program. The inductive function of gibberellins (GAs is the most documented. Abscisic acid (ABA has been demonstrated to delay flowering. Finally, the promotive role of brassinosteroids (BRs has been established. It has been reported that for many physiological processes, hormone pathways interact to ensure an appropriate biological response. METHODOLOGY: We tested possible genetic interactions between GA-, ABA-, and BR-dependent pathways in the control of the transition to flowering. For this, single and double mutants deficient in the biosynthesis of GAs, ABA, and BRs were used to assess the effect of hormone deficiency on the timing of floral transition. Also, plants that over-express genes encoding rate-limiting enzymes in each biosynthetic pathway were generated and the flowering time of these lines was investigated. CONCLUSIONS: Loss-of-function studies revealed a complex relationship between GAs and ABA, and between ABA and BRs, and suggested a cross-regulatory relation between GAs to BRs. Gain-of-function studies revealed that GAs were clearly limiting in their sufficiency of action, whereas increases in BRs and ABA led to a more modest phenotypic effect on floral timing. We conclude from our genetic tests that the effects of GA, ABA, and BR on timing of floral induction are only in partially coordinated action.

  2. Soluble proteins and polyphenoloxidase activity in bud flowers, flowers and leaves of cold stored lisianthus

    DEFF Research Database (Denmark)

    Cavasini, R.; Nunes, K.N.M.; Favero, B.T.;

    This study evaluated the activity of the enzyme polyphenol oxidase (PPO) and the content of soluble protein present in lisianthus bud flowers, flowers and leaves in room temperature (24±2°C) and pre-exposure cold chamber at 9±2°C for 24 h, in order to examine a possible correlation between these ...

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

    Science.gov (United States)

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

    2013-08-01

    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. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    1992-01-01

    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.

  5. The biology of flowering and structure of selected elements of Cornus alba L. flowers

    Directory of Open Access Journals (Sweden)

    Agata Konarska

    2012-12-01

    Full Text Available The biology of flowering and the micromorphology of Cornus alba flowers were studied using light and scanning electron microscopy. The flowering of white dogwood in 2008 lasted 35 days, and the lifespan of a single flower was 3 days. The number of flowers per inflorescence was variable (on the average, it was 89. The largest group of insects visiting the flowers of C. alba comprised Hymenoptera (mainly bees and andrenids, then ants, dipterans and beetles. They foraged the dogwood flowers most intensively between 11.00 and 15.00. The inconspicuous four-petalled flowers of C. alba were characterised by the occurrence of T-shaped, two-armed non-glandular trichomes covering the receptacle as well as observed on the petals of the corolla, the style of the pistil and the anthers in a smaller number. The trichomes were covered by a thick cuticle with characteristic outgrowths. They contained a living protoplast, and plastids were observed in the cytoplasm of the trichome cells. In addition, anomocytic stomata were found in the epidermis of the receptacle and in the epidermis of the corolla petals. The stigma of the pistil and the adaxial epidermis of the petals were composed of very numerous conical papillae.

  6. Divergence of flowering genes in soybean

    Indian Academy of Sciences (India)

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

    2012-11-01

    Soybean genome sequences were blasted with Arabidopsis thaliana regulatory genes involved in photoperiod-dependent 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.

  7. Flower volatiles, crop varieties and bee responses.

    Directory of Open Access Journals (Sweden)

    Björn K Klatt

    Full Text Available 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.

  8. Flower Men: The Australian Canon and Flower Painting 1910-1935

    Directory of Open Access Journals (Sweden)

    Ann Elias

    2008-12-01

    Full Text Available Historical studies of Hans Heysen, George Lambert, Tom Roberts and Arthur Streeton concentrate on paintings of landscape and people. Less well known are their paintings of flowers, which take the form of still-life painting or adjuncts to figure painting, such as portraits. While these artists are famous for the masculine way they approached masculine themes, and flower painting represents a stereotypically feminine subject, I argue that by making flowers their object of study, they intended to define and differentiate femininity from masculinity in an era of the ‘New Woman’. Sex and gender are central to the subject of flower painting and are important for discussions about the work produced by all four men, although sex is often camouflaged behind the innocence of naturalistically painted flowers.

  9. Kaempferol glycosides in the flowers of carnation and their contribution to the creamy white flower color.

    Science.gov (United States)

    Iwashina, Tsukasa; Yamaguchi, Masa-atsu; Nakayama, Masayoshi; Onozaki, Takashi; Yoshida, Hiroyuki; Kawanobu, Shuji; Onoe, Hiroshi; Okamura, Masachika

    2010-12-01

    Three flavonol glycosides were isolated from the flowers of carnation cultivars 'White Wink' and 'Honey Moon'. They were identified from their UV, MS, 1H and 13C NMR spectra as kaempferol 3-O-neohesperidoside, kaempferol 3-O-sophoroside and kaempferol 3-O-glucosyl-(1 --> 2)-[rhamnosyl-(1 --> 6)-glucoside]. Referring to previous reports, flavonols occurring in carnation flowers are characterized as kaempferol 3-O-glucosides with additional sugars binding at the 2 and/or 6-positions of the glucose. The kaempferol glycoside contents of a nearly pure white flower and some creamy white flower lines were compared. Although the major glycoside was different in each line, the total kaempferol contents of the creamy white lines were from 5.9 to 20.9 times higher than the pure white line. Thus, in carnations, kaempferol glycosides surely contribute to the creamy tone of white flowers.

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

    Science.gov (United States)

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

    2009-01-01

    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.

  11. Candidate genes within a 143 kb region of the flower sex locus in Vitis.

    Science.gov (United States)

    Fechter, Iris; Hausmann, Ludger; Daum, Margrit; Sörensen, Thomas Rosleff; Viehöver, Prisca; Weisshaar, Bernd; Töpfer, Reinhard

    2012-03-01

    Wild Vitis species are dioecious plants, while the cultivated counterpart, Vitis vinifera subspec. vinifera, generally shows hermaphroditic flowers. In Vitis the genetic determinants of flower sex have previously been mapped to a region on chromosome 2. In a combined strategy of map-based cloning and the use of the publicly available grapevine reference genome sequence, the structure of the grapevine flower sex locus has been elucidated with the subsequent identification of candidate genes which might be involved in the development of the different flower sex types. In a fine mapping approach, the sex locus in grapevine was narrowed down using a population derived from a cross of a genotype with a Vitis vinifera background ('Schiava Grossa' × 'Riesling') with the male rootstock cv. 'Börner' (V. riparia × V. cinerea). A physical map of 143 kb was established from BAC clones spanning the 0.5 cM region defined by the closest flanking recombination break points. Sequencing and gene annotation of the entire region revealed several candidate genes with a potential impact on flower sex formation. One of the presumed candidate genes, an adenine phosphoribosyltransferase, was analysed in more detail. The results led to the development of a marker for the presence or absence of the female alleles, while the male and hermaphroditic alleles are still to be differentiated. The impact of other candidate genes is discussed, especially with regard to plant hormone actions. The markers developed will permit the selection of female breeding lines which do not require laborious emasculation thus considerably simplifying grapevine breeding. The genetic finger prints displayed that our cultivated grapevines frequently carry a female allele while homozygous hermaphrodites are rare.

  12. Mediation of flowering by a calmodulin-dependent proteinkinase

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A calmodulin-dependent protein kinase (MCK1) appeared important in regulating flowering in tobacco. The expression of modified MCK1 that lacks the C-terminal including calmodulin-binding domain upsets the flowering developmental program, leading to the abortion of flower primordia initiated on the main axis of the plant and, as well, caused the prolongation of the vegetative phase in axillary buds. The abortion process of flowers began first in the developing anthers and subsequently the entire flower senesces. In axillary buds the prolonged vegetative phase was characterized by atypical elongated, narrow, twisted leaves. These results suggested a role for calmodulin-dependent protein kinase homologs in mediating flowering.

  13. Tiger cubs and little flowers.

    Science.gov (United States)

    1993-01-01

    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

  14. Orchid flowers tolerance to gamma-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Olivia Kimiko E-mail: okikuchi@net.ipen.br

    2000-03-01

    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.(author)

  15. Orchid flowers tolerance to gamma-radiation

    Science.gov (United States)

    Kikuchi, Olivia Kimiko

    2000-03-01

    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.

  16. Pollinators show flower colour preferences but flowers with similar colours do not attract similar pollinators.

    Science.gov (United States)

    Reverté, Sara; Retana, Javier; Gómez, José M; Bosch, Jordi

    2016-08-01

    Colour is one of the main floral traits used by pollinators to locate flowers. Although pollinators show innate colour preferences, the view that the colour of a flower may be considered an important predictor of its main pollinators is highly controversial because flower choice is highly context-dependent, and initial innate preferences may be overridden by subsequent associative learning. Our objective is to establish whether there is a relationship between flower colour and pollinator composition in natural communities. We measured the flower reflectance spectrum and pollinator composition in four plant communities (85 plant species represented by 109 populations, and 32 305 plant-pollinator interactions in total). Pollinators were divided into six taxonomic groups: bees, ants, wasps, coleopterans, dipterans and lepidopterans. We found consistent associations between pollinator groups and certain colours. These associations matched innate preferences experimentally established for several pollinators and predictions of the pollination syndrome theory. However, flowers with similar colours did not attract similar pollinator assemblages. The explanation for this paradoxical result is that most flower species are pollination generalists. We conclude that although pollinator colour preferences seem to condition plant-pollinator interactions, the selective force behind these preferences has not been strong enough to mediate the appearance and maintenance of tight colour-based plant-pollinator associations. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Flower Constancy, Insect Psychology, and Plant Evolution

    Science.gov (United States)

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

    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.

  18. Refuges, flower strips, biodiversity and agronomic interest.

    Science.gov (United States)

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

    2008-01-01

    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

  19. Glyphosate and Dicamba Inhibit Flowering of Native Willamette Valley Plants

    Science.gov (United States)

    Successful flowering is essential for reproduction of native plants and production of food for herbivores. It is also an important alternative endpoint for assessment of ecological risks from chemical stressors such as herbicides. We evaluated flowering phenology after herbicide...

  20. DNA tests for strawberry: perpetual flowering - Bx215

    Science.gov (United States)

    Perpetual flowering strawberries have great economic value to the fresh market industry. Floral initiation in strawberry is largely determined by photoperiod, temperature, and genetics. Commercially grown strawberries are generally classified as remontant (repeated or perpetual flowering, day neutr...

  1. Impact of Cut-Flower Industries on Sustainable Livelihood and ...

    African Journals Online (AJOL)

    Impact of Cut-Flower Industries on Sustainable Livelihood and Poverty Reduction in ... Annals of Humanities and Development Studies ... A sample of 200 respondents were obtained from five cut-flower companies, including Kiliflora, Tanzania ...

  2. Glyphosate and Dicamba Inhibit Flowering of Native Willamette Valley Plants

    Science.gov (United States)

    Successful flowering is essential for reproduction of native plants and production of food for herbivores. It is also an important alternative endpoint for assessment of ecological risks from chemical stressors such as herbicides. We evaluated flowering phenology after herbicide...

  3. Experimental Studies Cast Doubt on Deceit Syndrome of Bat Flower

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Bat Flower (Tacca chantrieri) is a southwest China's species of a tropical plant genus called Tacca,which features near black flowers,conspicuous involucral bracts and whisker-like filiform bracteoles.

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

    Science.gov (United States)

    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

    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.

  5. Flowering and sex expression in Acer L. : a biosystemic study

    NARCIS (Netherlands)

    Jong, de P.C.

    1976-01-01

    A review and an analysis is given of flowering and sex expression in Acer. The process of sex differentiation was studied in physiological experiments and could be influenced by accelerated flowering and by removal of female.gif flower buds just after bud break. The paper further includes notes on t

  6. Vascular occlusion in stems of cut rose flowers

    NARCIS (Netherlands)

    Doorn, van W.G.

    1993-01-01

    The quality of cut rose flowers, a major horticultural crop in the Netherlands, is often unsatisfactory. During vase-life premature signs of water stress occur, such as slow growth of the bud which often results in poor flower opening, wilting of both the flowers and the leaves, and bending

  7. The Symbolic Meanings of “Flowering Judas”

    Institute of Scientific and Technical Information of China (English)

    Tian Yan

    2014-01-01

    In the short story “Flowering Judas”, Katherine Anne Porter employed the writing technique - symbolism. Among others, “Flowering Judas” is the most important symbolic image. This paper tries to analyze the symbolic meanings of “Flowering Judas”, so that the readers can understand the theme of the this story much better.

  8. The Symbolic Meanings of “Flowering Judas”

    Institute of Scientific and Technical Information of China (English)

    Tian; Yan

    2014-01-01

    In the short story"Flowering Judas",Katherine Anne Porter employed the writing technique—symbolism.Among others,"Flowering Judas"is the most important symbolic image.This paper tries to analyze the symbolic meanings of"Flowering Judas",so that the readers can understand the theme of the this story much better.

  9. Internet log service for flower supply chains

    NARCIS (Netherlands)

    Thors, M.

    2004-01-01

    Onderzoekers van Agrotechnology & Food Innovations van Wageningen UR hebben data ontwikkelt en getest om de kwaliteit en houdbaarheid van snijbloemen tijdens langdurig transport te behoudenThis summer has seen the completion of a project to develop quality tracking and tracing for cut flowers. S

  10. Gravitropism in cut flower stalks of snapdragon

    NARCIS (Netherlands)

    Philosoph-Hadas, S.; Friedman, H.; Meir, S.; Berkovitz-SimanTov, R.; Rosenberger, I.; Halevy, A.H.; Kaufman, P.B.; Balk, P.; Woltering, E.J.

    2002-01-01

    The negative gravitropic response of cut flower stalks is a complex multistep process that requires the participation of various cellular components acting in succession or in parallel. The process was particularly characterized in snapdragon (Antirrhinum majus L.) spikes with regard to (1) gravity

  11. Teaching Art with Art: Flowers in Art.

    Science.gov (United States)

    Hubbard, Guy

    1998-01-01

    Justifies examining still-life pictures of flowers to provide students with an opportunity to learn how one distinguishes between deeply artistic pictures full of emotion and pictures lacking this quality. Claims that students will develop their own artistic expression. Offers pictures by Diego Rivera, Watanabe Shiko, Consuelo Kanaga, and Rachel…

  12. Gravitropism in cut flower stalks of snapdragon

    NARCIS (Netherlands)

    Philosoph-Hadas, S.; Friedman, H.; Meir, S.; Berkovitz-SimanTov, R.; Rosenberger, I.; Halevy, A.H.; Kaufman, P.B.; Balk, P.; Woltering, E.J.

    2002-01-01

    The negative gravitropic response of cut flower stalks is a complex multistep process that requires the participation of various cellular components acting in succession or in parallel. The process was particularly characterized in snapdragon (Antirrhinum majus L.) spikes with regard to (1) gravity

  13. Alkaloids of the flowers of Pancratium maritimum.

    Science.gov (United States)

    Youssef, D T; Frahm, A W

    1998-10-01

    The defatted ethanolic extract of the fresh flowers of Pancratium maritimum L. yielded the four known alkaloids lycorine, maritidine, lycoramine, and galanthamine. The structures of the isolated alkaloids were determined mainly through spectroscopic studies including one- and two-dimensional NMR (COSY, NOESY, DEPT, HETCOR, and HMBC) and CD techniques. Some spectral data are newly reported or revised.

  14. Interspecific hybridization of flower bulbs: a review

    NARCIS (Netherlands)

    Tuyl, van J.M.

    1997-01-01

    In order to introduce new characters such as resistances, flower shape and colour, from wild species into the cultivar assortment of lily it is necessary to overcome interspecific crossing barriers.. Several techniques have been used for wide interspecific lily crosses with species and cultivars fro

  15. Teaching Art with Art: Flowers in Art.

    Science.gov (United States)

    Hubbard, Guy

    1998-01-01

    Justifies examining still-life pictures of flowers to provide students with an opportunity to learn how one distinguishes between deeply artistic pictures full of emotion and pictures lacking this quality. Claims that students will develop their own artistic expression. Offers pictures by Diego Rivera, Watanabe Shiko, Consuelo Kanaga, and Rachel…

  16. Interspecific hybridization of flower bulbs: a review

    NARCIS (Netherlands)

    Tuyl, van J.M.

    1997-01-01

    In order to introduce new characters such as resistances, flower shape and colour, from wild species into the cultivar assortment of lily it is necessary to overcome interspecific crossing barriers.. Several techniques have been used for wide interspecific lily crosses with species and cultivars

  17. Interspecific hybridization of flower bulbs: a review

    NARCIS (Netherlands)

    Tuyl, van J.M.

    1997-01-01

    In order to introduce new characters such as resistances, flower shape and colour, from wild species into the cultivar assortment of lily it is necessary to overcome interspecific crossing barriers.. Several techniques have been used for wide interspecific lily crosses with species and cultivars fro

  18. Preference and performance of western flower thrips

    NARCIS (Netherlands)

    Kogel, de W.J.

    2002-01-01

    Differences in performance on, and preference for, different plant parts were studied on cucumber plants. On these plants thrips are often most abundant on the youngest plant parts. This suggests that the youngest leaves are most suitable for western flower thrips. We assessed if differences in

  19. Internet log service for flower supply chains

    NARCIS (Netherlands)

    Thors, M.

    2004-01-01

    Onderzoekers van Agrotechnology & Food Innovations van Wageningen UR hebben data ontwikkelt en getest om de kwaliteit en houdbaarheid van snijbloemen tijdens langdurig transport te behoudenThis summer has seen the completion of a project to develop quality tracking and tracing for cut flowers. S

  20. Molecular mechanism of TFL1 on the regulation of flowering time in Rosaceae%TFL1调控蔷薇科植物开花时间的分子机制

    Institute of Scientific and Technical Information of China (English)

    高用顺; 汪以; 朱云美; 林顺权

    2016-01-01

    The rose family (Rosaceae),consists of numerous horticultural plants that have significant economic value.The family includes strawberry,raspberry and rose in the Rosoideae subfamily;fruit trees of apple,pear and loquat in the Maloideae subfamily;and peach,plum and apricot in the Prunoideae subfamily.Consisting of herbaceous plants and woody fruits,the rosaceous plants present various modes of flowering,and the different flowering modes directly influence the flowering ornamental period and/or the fruit harvest period,which are both very important in the horticulture industry.Flowering is the vital physiological process for fruiting,and it is the mark for the transitio n from vegetative to reproductive growth,which is also known as floral transition.In Arabidopsis,a genus in the Brassicaceae family,FLOWERINGLOCUS T (FT) is a key florigen,which integrates the signals regulated by the internal and external environmental cues,and it works at the shoot apical meristem (SAM) to activate the downstream signals for floral transition.TERMINAL FLOWER1 (TFL1) is a homologous gene of FT,which is originally reported in Arabidopsis,the function of TFL1 is opposite to FT,as it plays a role in delaying flowering time.TFL1 suppresses the expression of the downstream genes like LEAFY (LFY),flower meristem identity genes APETALA1 (AP1) and CAULIFLOWER (CAL),and thereby consequently inhibits flowering.The till mutant shows determinate inflorescence and early flowering phenotype.FT can bind with another flowering transcription factor FLOWERING LOCUS D (FD) and form a strong activator to promote the expression of downstream genes,however,when FD binds with TFL1,they form to become a powerful suppressor and inhibit flowering.In the process of vegetative growth,TFL1 strongly expresses in the central area of the inflorescence meristem,and suppresses the translation of AP1 and LFY,in order to keep the meristem at an undifferentiated status.In wild strawberry Fragaria vesca,FvTFL1 highly

  1. Growth Hormone Deficiency

    Directory of Open Access Journals (Sweden)

    Ömer Tarım

    2010-05-01

    Full Text Available Growth hormone deficiency is the most promising entity in terms of response to therapy among the treatable causes of growth retardation. It may be due to genetic or acquired causes. It may be isolated or a part of multiple hormone deficiencies. Diagnostic criteria and therefore treatment indications are still disputed. (Journal of Current Pediatrics 2010; 8: 36-8

  2. The date palm (Phoenix dactylifera L.) micropropagation using completely mature female flowers.

    Science.gov (United States)

    Kriaa, Walid; Sghaier-Hammami, Besma; Masmoudi-Allouche, Faïza; Benjemaa-Masmoudi, Raja; Drira, Noureddine

    2012-03-01

    This study describes an efficient and reproducible protocol for in vitro date palm propagation using mature female flowers. It focuses on the promising proliferation capacity exhibited by a number of female flower tissues taken at the final developmental stage. This capacity resided in the ability to preserve minuscule zones in a juvenile state located at the floral organ armpits (sepals and petals). The originality of this method lies in the possibility of propagation of very rare varieties, particularly the genotypes that exist in only one copy without the excision of the plant mother, the source of the tissue collected to be cultivated, which was not the case for all previous methods. The findings revealed that 2,4-D at 1mg/l, most of the varieties tested showed reactivity. The success of this technique was also noted to depend on the concurrent control of various factors pertaining mainly to the hormonal composition of the culture medium and the appropriate time of tissue transfer, which depends on the proliferation state as well as the culture period. This study describes the nature of the proliferation from the mature female flowers and their outcome, particularly those at the origin of embryogenic and budding strains and discusses the advantages of this novel multiplication method as compared to the currently available ones.

  3. Activation of Defense Mechanisms against Pathogens in Mosses and Flowering Plants.

    Science.gov (United States)

    Ponce de León, Inés; Montesano, Marcos

    2013-02-04

    During evolution, plants have developed mechanisms to cope with and adapt to different types of stress, including microbial infection. Once the stress is sensed, signaling pathways are activated, leading to the induced expression of genes with different roles in defense. Mosses (Bryophytes) are non-vascular plants that diverged from flowering plants more than 450 million years ago, allowing comparative studies of the evolution of defense-related genes and defensive metabolites produced after microbial infection. The ancestral position among land plants, the sequenced genome and the feasibility of generating targeted knock-out mutants by homologous recombination has made the moss Physcomitrella patens an attractive model to perform functional studies of plant genes involved in stress responses. This paper reviews the current knowledge of inducible defense mechanisms in P. patens and compares them to those activated in flowering plants after pathogen assault, including the reinforcement of the cell wall, ROS production, programmed cell death, activation of defense genes and synthesis of secondary metabolites and defense hormones. The knowledge generated in P. patens together with comparative studies in flowering plants will help to identify key components in plant defense responses and to design novel strategies to enhance resistance to biotic stress.

  4. Hormonal Regulators of Appetite

    Directory of Open Access Journals (Sweden)

    Juliana Austin

    2009-01-01

    Full Text Available Obesity is a significant cause of morbidity and mortality worldwide. There has been a significant worsening of the obesity epidemic mainly due to alterations in dietary intake and energy expenditure. Alternatively, cachexia, or pathologic weight loss, is a significant problem for individuals with chronic disease. Despite their obvious differences, both processes involve hormones that regulate appetite. These hormones act on specific centers in the brain that affect the sensations of hunger and satiety. Mutations in these hormones or their receptors can cause substantial pathology leading to obesity or anorexia. Identification of individuals with specific genetic mutations may ultimately lead to more appropriate therapies targeted at the underlying disease process. Thus far, these hormones have mainly been studied in adults and animal models. This article is aimed at reviewing the hormones involved in hunger and satiety, with a focus on pediatrics.

  5. Hormonal Regulators of Appetite

    Directory of Open Access Journals (Sweden)

    Austin Juliana

    2008-11-01

    Full Text Available Obesity is a significant cause of morbidity and mortality worldwide. There has been a significant worsening of the obesity epidemic mainly due to alterations in dietary intake and energy expenditure. Alternatively, cachexia, or pathologic weight loss, is a significant problem for individuals with chronic disease. Despite their obvious differences, both processes involve hormones that regulate appetite. These hormones act on specific centers in the brain that affect the sensations of hunger and satiety. Mutations in these hormones or their receptors can cause substantial pathology leading to obesity or anorexia. Identification of individuals with specific genetic mutations may ultimately lead to more appropriate therapies targeted at the underlying disease process. Thus far, these hormones have mainly been studied in adults and animal models. This article is aimed at reviewing the hormones involved in hunger and satiety, with a focus on pediatrics.

  6. Heart, lipids and hormones

    Directory of Open Access Journals (Sweden)

    Peter Wolf

    2017-05-01

    Full Text Available Cardiovascular disease is the leading cause of death in general population. Besides well-known risk factors such as hypertension, impaired glucose tolerance and dyslipidemia, growing evidence suggests that hormonal changes in various endocrine diseases also impact the cardiac morphology and function. Recent studies highlight the importance of ectopic intracellular myocardial and pericardial lipid deposition, since even slight changes of these fat depots are associated with alterations in cardiac performance. In this review, we overview the effects of hormones, including insulin, thyroid hormones, growth hormone and cortisol, on heart function, focusing on their impact on myocardial lipid metabolism, cardiac substrate utilization and ectopic lipid deposition, in order to highlight the important role of even subtle hormonal changes for heart function in various endocrine and metabolic diseases.

  7. 生长素调节植物花发育的研究进展%Research Progress on Auxin Regulation in Flower DeveloPment

    Institute of Scientific and Technical Information of China (English)

    严希; 彭剑涛

    2015-01-01

    花是被子植物的繁殖器官,花的发育是植物繁衍后代的关键环节。大量研究表明,花发育受到基因、植物激素、温度等多种内外因素的调控,生长素在此过程中扮演着不可或缺的角色。本文介绍了国内外生长素调控花发育研究的进展,尤其是生长素极性运输、生长素含量变化以及生长素信号转导在花器官发育过程中的作用。%Flower is the reproductive organ of angiosperm,and flower development is the key step in the progress of reproduction. Numerous researches have indicated that flower development is regulated by genes,plant hor-mones,temperature,and so on. Plant hormones,especially auxin,play indispensable roles in regulation of flow-er development. In this review we introduced the research progress on auxin regulation in flower development. Effects of polar auxin transport,changes in auxin contents and auxin signal transduction on the development of flower were reviewed in particular.

  8. Aging changes in hormone production

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/004000.htm Aging changes in hormone production To use the sharing ... that produce hormones are controlled by other hormones. Aging also changes this process. For example, an endocrine ...

  9. Flower colour and cytochromes P450.

    Science.gov (United States)

    Tanaka, Yoshikazu; Brugliera, Filippa

    2013-02-19

    Cytochromes P450 play important roles in biosynthesis of flavonoids and their coloured class of compounds, anthocyanins, both of which are major floral pigments. The number of hydroxyl groups on the B-ring of anthocyanidins (the chromophores and precursors of anthocyanins) impact the anthocyanin colour, the more the bluer. The hydroxylation pattern is determined by two cytochromes P450, flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) and thus they play a crucial role in the determination of flower colour. F3'H and F3'5'H mostly belong to CYP75B and CYP75A, respectively, except for the F3'5'Hs in Compositae that were derived from gene duplication of CYP75B and neofunctionalization. Roses and carnations lack blue/violet flower colours owing to the deficiency of F3'5'H and therefore lack the B-ring-trihydroxylated anthocyanins based upon delphinidin. Successful redirection of the anthocyanin biosynthesis pathway to delphinidin was achieved by expressing F3'5'H coding regions resulting in carnations and roses with novel blue hues that have been commercialized. Suppression of F3'5'H and F3'H in delphinidin-producing plants reduced the number of hydroxyl groups on the anthocyanidin B-ring resulting in the production of monohydroxylated anthocyanins based on pelargonidin with a shift in flower colour to orange/red. Pelargonidin biosynthesis is enhanced by additional expression of a dihydroflavonol 4-reductase that can use the monohydroxylated dihydrokaempferol (the pelargonidin precursor). Flavone synthase II (FNSII)-catalysing flavone biosynthesis from flavanones is also a P450 (CYP93B) and contributes to flower colour, because flavones act as co-pigments to anthocyanins and can cause blueing and darkening of colour. However, transgenic plants expression of a FNSII gene yielded paler flowers owing to a reduction of anthocyanins because flavanones are precursors of anthocyanins and flavones.

  10. Cyanogenic Glucosides and Derivatives in Almond and Sweet Cherry Flower Buds from Dormancy to Flowering

    Science.gov (United States)

    Del Cueto, Jorge; Ionescu, Irina A.; Pičmanová, Martina; Gericke, Oliver; Motawia, Mohammed S.; Olsen, Carl E.; Campoy, José A.; Dicenta, Federico; Møller, Birger L.; Sánchez-Pérez, Raquel

    2017-01-01

    Almond and sweet cherry are two economically important species of the Prunus genus. They both produce the cyanogenic glucosides prunasin and amygdalin. As part of a two-component defense system, prunasin and amygdalin release toxic hydrogen cyanide upon cell disruption. In this study, we investigated the potential role within prunasin and amygdalin and some of its derivatives in endodormancy release of these two Prunus species. The content of prunasin and of endogenous prunasin turnover products in the course of flower development was examined in five almond cultivars – differing from very early to extra-late in flowering time – and in one sweet early cherry cultivar. In all cultivars, prunasin began to accumulate in the flower buds shortly after dormancy release and the levels dropped again just before flowering time. In almond and sweet cherry, the turnover of prunasin coincided with increased levels of prunasin amide whereas prunasin anitrile pentoside and β-D-glucose-1-benzoate were abundant in almond and cherry flower buds at certain developmental stages. These findings indicate a role for the turnover of cyanogenic glucosides in controlling flower development in Prunus species. PMID:28579996

  11. Cyanogenic Glucosides and Derivatives in Almond and Sweet Cherry Flower Buds from Dormancy to Flowering

    Directory of Open Access Journals (Sweden)

    Jorge Del Cueto

    2017-05-01

    Full Text Available Almond and sweet cherry are two economically important species of the Prunus genus. They both produce the cyanogenic glucosides prunasin and amygdalin. As part of a two-component defense system, prunasin and amygdalin release toxic hydrogen cyanide upon cell disruption. In this study, we investigated the potential role within prunasin and amygdalin and some of its derivatives in endodormancy release of these two Prunus species. The content of prunasin and of endogenous prunasin turnover products in the course of flower development was examined in five almond cultivars – differing from very early to extra-late in flowering time – and in one sweet early cherry cultivar. In all cultivars, prunasin began to accumulate in the flower buds shortly after dormancy release and the levels dropped again just before flowering time. In almond and sweet cherry, the turnover of prunasin coincided with increased levels of prunasin amide whereas prunasin anitrile pentoside and β-D-glucose-1-benzoate were abundant in almond and cherry flower buds at certain developmental stages. These findings indicate a role for the turnover of cyanogenic glucosides in controlling flower development in Prunus species.

  12. Hormones and female sexuality

    Directory of Open Access Journals (Sweden)

    Bjelica Artur L.

    2003-01-01

    Full Text Available Introduction In contrast to animal species in which linear relationships exist between hormonal status and sexual behaviour sexuality in human population is not determined so simply by the level of sexual steroids. The article analyses female sexuality in the light of hormonal status. Administration of sexual steroids during pregnancy and sexual differentiation High doses of gestagens, especially those with high androgen activity, widely used against miscarriages may lead to tomboys, but without differences in sexual orientation. However, it has been observed that the frequency of bisexual and lesbian women is higher in women with congenital adrenogenital syndrome. Hormones sexual desire and sexuality during menstrual cycle It has been established that sexual desire, autoeroticism and sexual fantasies in women depend on androgen levels. There are a lot of reports claiming that sexual desire varies during the menstrual cycle. Hormonal contraception and sexuality Most patients using birth control pills present with decreased libido. But, there are reports that progestagens with antiandrogenic effect in contraceptive pills do not affect sexual desire. Hormonal changes in peri- and postmenopausal period and sexuality Decreased levels of estrogen and testosterone in older women are associated with decreased libido, sensitivity and erotic stimuli. Sexuality and hormone replacement therapy Hormonal therapy with estrogen is efficient in reference to genital atrophy, but not to sexual desire. Really increased libido is achieved using androgens. Also, therapy with dehydroepiandrosterone (DHEA and tibolone have positive effects on female libido. Conclusion Effect of sexual steroids on sexual sphere of women is very complex. The association between hormones and sexuality is multidimensional, as several hormones are important in regulation of sexual behaviour. Still, it should be pointed out that sexuality is in the domain of hormonal, emotional

  13. Endogenous ethylene does not regulate opening of unstressed Iris flowers but strongly inhibits it in water-stressed flowers

    NARCIS (Netherlands)

    Celikel, F.G.; Doorn, van W.G.

    2012-01-01

    The floral buds of Iris flowers (Iris x hollandica) are enclosed by two sheath leaves. Flower opening depends on lifting the flower up to a position whereby the tepals can move laterally. This upward movement is carried out by elongation of the subtending pedicel and ovary. In the pedicels and ovari

  14. DELAYED FLOWERING, an Arabidopsis Gene That Acts in the Autonomous Flowering Promotion Pathway and Is Required for Normal Development

    Institute of Scientific and Technical Information of China (English)

    Ming-Jie Chen; Zheng Yuan; Hai Huang

    2006-01-01

    The control of flowering time in higher plants is one of the most important physiological processes and is critical for their reproductive success. To investigate the mechanisms controlling flowering time, we screened for Arabidopsis mutants with late-flowering phenotypes. One mutant, designated delayed flowering (dfr) in the Landsberg erecta (Ler) ecotype, was identified with delayed flowering time. Genetic analysis revealed that dfr is a single gene recessive nuclear mutant and the mutation was mapped to a locus tightly linked to UFO on chromosome 1. To our knowledge, no gene regulating flowering time has been reported yet in this region. The dfr mutant plant showed a delayed flowering time under the different growth conditions examined,including long- and short-day photoperiods and gibberellic acid GA3 treatments, suggesting that DFR is a gene involved in the autonomous flowering promotion pathway. The Arabidopsis gene FLOWERING LOCUS C (FLC) plays a central role in repressing flowering and its transcripts are undetectable in wild-type Ler.However, FLCexpression was upregulated in the dfrmutant, suggesting that DFR is a negative regulator of FLC. In addition, the dfr mutant plant displayed altered valve shapes of the silique and the number of trichomes and branches of each trichome were both reduced, indicating that the DRFgene is also required for normal plant development. Moreover, dfr leafy-5 (Ify-5) double mutant plants showed a much later flowering time than either dfr or Ify-5 single mutants, indicating that DFR and LFYact synergistically to promote flowering in Arabidopsis.

  15. Analysis on Structure of Flower Market in Beijing

    Institute of Scientific and Technical Information of China (English)

    Xi; SUN; Yingying; ZHANG

    2015-01-01

    with the socio-economic development and people’s living condition improvement,the requirement for environment is higher and higher and the mental demand is also more and more.For this,Beijing Municipal Bureau of Landscape and Forestry listed survey programs of consumption demands of flower market in Beijing in 2014,and provided several recommendations in line with current situations,problems and environment of the flower industry,for future reference of flower decision making of Beijing.In March 2014,the authors carried out survey in flower market of Beijing and participated in survey of management of flower industry.In May of the same year,combining this study,they visited ten districts(counties),including Dongcheng,Xicheng,Chaoyang,Fengtai,Shijingshan,and Daxing,together with relevant flower researchers,and carried out in-depth survey in several districts(counties)with better foundation of flower industry.Besides,with reference to China Flower&Gardening; News and China Flowers&Horticulture;,and relevant literature,it summarized and sorted out many years of various materials and statistical data of flower industry in Beijing.On the basis of surveying different flower markets and production areas and analyzing relevant data,the authors visited famous flower enterprises and large flower production and sales households in Beijing,elaborated current situations of Beijing flower industry in industrial foundation,development environment,industrial distribution,product type,and circulation field,and pointed out major problems in product type,market structure,production cost,service system,and logistics channels.Finally,it came up with practical and feasible solutions,hoping to provide certain reference for excellent development of flower industry in Beijing.

  16. Color versus bioactivity in the flowers of Bougainvillea spectabilis (Nyctaginaceae).

    Science.gov (United States)

    Ali, Muhammad Shaiq; Ibrahim, Syed Amir; Ahmed, Farman; Pervez, Muhammad Kashif

    2005-01-01

    The methanolic extracts of Bougainvillea spectabilis (Nyctaginaceae) flowers (five different colors) were screened biologically by performing four bioassays: antibacterial, antifungal, brine shrimp lethality and phytotoxicity. It was observed that the methanolic extract of white flowers was the most biologically active among all tested extracts. The extracts of white, orange and shocking pink flowers inhibit, while the extracts of red and violet flowers promote, the growth of Lemna plants. The extract of white flowers also exhibits toxicity against shrimp larvae with a LD50 value of 33.5627 microg/mL. However, none of the tested samples gave positive responses against any tested fungi.

  17. Mobile Application to Identify Indonesian Flowers on Android Platform

    Directory of Open Access Journals (Sweden)

    Tita Karlita

    2013-12-01

    Full Text Available Although many people love flowers, they do not know their name. Especially, many people do not recognize local flowers. To find the flower image, we can use search engine such as Google, but it does not give much help to find the name of local flower. Sometimes, Google cannotshow the correct name of local flowers. This study proposes an application to identify Indonesian flowers that runs on the Android platform for easy use anywhere. Flower recognition is based on the color features using the Hue-Index, shape feature using Centroid Contour Distance (CCD, and the similarity measurement using Entropy calculations. The outputs of this application are information about inputted flower image including Latinname, local name, description, distribution and ecology. Based on tests performed on 44 types of flowers with 181 images in the database, the best similarity percentage is 97.72%. With this application, people will be expected to know more about Indonesia flowers. Keywords: Indonesian flowers, android, hue-index, CCD, entropy

  18. Models for forecasting the flowering of Cornicabra olive groves

    Science.gov (United States)

    Rojo, Jesús; Pérez-Badia, Rosa

    2015-11-01

    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.

  19. Models for forecasting the flowering of Cornicabra olive groves.

    Science.gov (United States)

    Rojo, Jesús; Pérez-Badia, Rosa

    2015-11-01

    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.

  20. A flower image retrieval method based on ROI feature

    Institute of Scientific and Technical Information of China (English)

    洪安祥; 陈刚; 李均利; 池哲儒; 张亶

    2004-01-01

    Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images. For flower retrieval, we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets, Centroid-Contour Distance (CCD) and Angle Code Histogram (ACH), to characterize the shape features of a flower contour. Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions. Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest (ROI) based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard (1991) and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999).

  1. A flower image retrieval method based on ROI feature

    Institute of Scientific and Technical Information of China (English)

    洪安祥; 陈刚; 李均利; 池哲儒; 张亶

    2004-01-01

    Flower image retrieval is a very important step for computer-aided plant species recognition.In this paper,we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images.For flower retrieval,we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets,Centroid-Contour Distance(CCD)and Angle Code Histogram(ACH),to characterize the shape features of a flower contour.Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions.Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest(ROD based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard(1991)and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999).

  2. Developmental morphology of branching flowers in Nymphaea prolifera.

    Science.gov (United States)

    Grob, Valentin; Moline, Philip; Pfeifer, Evelin; Novelo, Alejandro R; Rutishauser, Rolf

    2006-11-01

    Nymphaea and Nuphar (Nymphaeaceae) share an extra-axillary mode of floral inception in the shoot apical meristem (SAM). Some leaf sites along the ontogenetic spiral are occupied by floral primordia lacking a subtending bract. This pattern of flower initiation in leaf sites is repeated inside branching flowers of Nymphaea prolifera (Central and South America). Instead of fertile flowers this species usually produces sterile tuberiferous flowers that act as vegetative propagules. N. prolifera changes the meristem identity from reproductive to vegetative or vice versa repeatedly. Each branching flower first produces some perianth-like leaves, then it switches back to the vegetative meristem identity of the SAM with the formation of foliage leaves and another set of branching flowers. This process is repeated up to three times giving rise to more than 100 vegetative propagules. The developmental morphology of the branching flowers of N. prolifera is described using both microtome sections and scanning electron microscopy.

  3. Dynamics of Jasmonate Metabolism upon Flowering and across Leaf Stress Responses in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Emilie Widemann

    2016-01-01

    Full Text Available The jasmonic acid (JA signaling pathway plays important roles in adaptation of plants to environmental cues and in specific steps of their development, particularly in reproduction. Recent advances in metabolic studies have highlighted intricate mechanisms that govern enzymatic conversions within the jasmonate family. Here we analyzed jasmonate profile changes upon Arabidopsis thaliana flower development and investigated the contribution of catabolic pathways that were known to turnover the active hormonal compound jasmonoyl-isoleucine (JA-Ile upon leaf stress. We report a rapid decline of JA-Ile upon flower opening, concomitant with the massive accumulation of its most oxidized catabolite, 12COOH-JA-Ile. Detailed genetic analysis identified CYP94C1 as the major player in this process. CYP94C1 is one out of three characterized cytochrome P450 enzymes that define an oxidative JA-Ile turnover pathway, besides a second, hydrolytic pathway represented by the amido-hydrolases IAR3 and ILL6. Expression studies combined with reporter gene analysis revealed the dominant expression of CYP94C1 in mature anthers, consistent with the established role of JA signaling in male fertility. Significant CYP94B1 expression was also evidenced in stamen filaments, but surprisingly, CYP94B1 deficiency was not associated with significant changes in JA profiles. Finally, we compared global flower JA profiles with those previously reported in leaves reacting to mechanical wounding or submitted to infection by the necrotrophic fungus Botrytis cinerea. These comparisons revealed distinct dynamics of JA accumulation and conversions in these three biological systems. Leaf injury boosts a strong and transient JA and JA-Ile accumulation that evolves rapidly into a profile dominated by ω-oxidized and/or Ile-conjugated derivatives. In contrast, B. cinerea-infected leaves contain mostly unconjugated jasmonates, about half of this content being ω-oxidized. Finally, developing

  4. Dynamics of Jasmonate Metabolism upon Flowering and across Leaf Stress Responses in Arabidopsis thaliana.

    Science.gov (United States)

    Widemann, Emilie; Smirnova, Ekaterina; Aubert, Yann; Miesch, Laurence; Heitz, Thierry

    2016-01-06

    The jasmonic acid (JA) signaling pathway plays important roles in adaptation of plants to environmental cues and in specific steps of their development, particularly in reproduction. Recent advances in metabolic studies have highlighted intricate mechanisms that govern enzymatic conversions within the jasmonate family. Here we analyzed jasmonate profile changes upon Arabidopsis thaliana flower development and investigated the contribution of catabolic pathways that were known to turnover the active hormonal compound jasmonoyl-isoleucine (JA-Ile) upon leaf stress. We report a rapid decline of JA-Ile upon flower opening, concomitant with the massive accumulation of its most oxidized catabolite, 12COOH-JA-Ile. Detailed genetic analysis identified CYP94C1 as the major player in this process. CYP94C1 is one out of three characterized cytochrome P450 enzymes that define an oxidative JA-Ile turnover pathway, besides a second, hydrolytic pathway represented by the amido-hydrolases IAR3 and ILL6. Expression studies combined with reporter gene analysis revealed the dominant expression of CYP94C1 in mature anthers, consistent with the established role of JA signaling in male fertility. Significant CYP94B1 expression was also evidenced in stamen filaments, but surprisingly, CYP94B1 deficiency was not associated with significant changes in JA profiles. Finally, we compared global flower JA profiles with those previously reported in leaves reacting to mechanical wounding or submitted to infection by the necrotrophic fungus Botrytis cinerea. These comparisons revealed distinct dynamics of JA accumulation and conversions in these three biological systems. Leaf injury boosts a strong and transient JA and JA-Ile accumulation that evolves rapidly into a profile dominated by ω-oxidized and/or Ile-conjugated derivatives. In contrast, B. cinerea-infected leaves contain mostly unconjugated jasmonates, about half of this content being ω-oxidized. Finally, developing flowers present an

  5. Dynamics of Jasmonate Metabolism upon Flowering and across Leaf Stress Responses in Arabidopsis thaliana

    Science.gov (United States)

    Widemann, Emilie; Smirnova, Ekaterina; Aubert, Yann; Miesch, Laurence; Heitz, Thierry

    2016-01-01

    The jasmonic acid (JA) signaling pathway plays important roles in adaptation of plants to environmental cues and in specific steps of their development, particularly in reproduction. Recent advances in metabolic studies have highlighted intricate mechanisms that govern enzymatic conversions within the jasmonate family. Here we analyzed jasmonate profile changes upon Arabidopsis thaliana flower development and investigated the contribution of catabolic pathways that were known to turnover the active hormonal compound jasmonoyl-isoleucine (JA-Ile) upon leaf stress. We report a rapid decline of JA-Ile upon flower opening, concomitant with the massive accumulation of its most oxidized catabolite, 12COOH-JA-Ile. Detailed genetic analysis identified CYP94C1 as the major player in this process. CYP94C1 is one out of three characterized cytochrome P450 enzymes that define an oxidative JA-Ile turnover pathway, besides a second, hydrolytic pathway represented by the amido-hydrolases IAR3 and ILL6. Expression studies combined with reporter gene analysis revealed the dominant expression of CYP94C1 in mature anthers, consistent with the established role of JA signaling in male fertility. Significant CYP94B1 expression was also evidenced in stamen filaments, but surprisingly, CYP94B1 deficiency was not associated with significant changes in JA profiles. Finally, we compared global flower JA profiles with those previously reported in leaves reacting to mechanical wounding or submitted to infection by the necrotrophic fungus Botrytis cinerea. These comparisons revealed distinct dynamics of JA accumulation and conversions in these three biological systems. Leaf injury boosts a strong and transient JA and JA-Ile accumulation that evolves rapidly into a profile dominated by ω-oxidized and/or Ile-conjugated derivatives. In contrast, B. cinerea-infected leaves contain mostly unconjugated jasmonates, about half of this content being ω-oxidized. Finally, developing flowers present an

  6. Migraine and Hormones.

    Science.gov (United States)

    Pakalnis, Ann

    2016-02-01

    This article discusses the role that hormones play in adolescent girls and young women with headaches, which are very common in adolescent girls, in particular, migraine. In many cases, migraine onset may occur shortly around the time of menarche, prevalence of recurrent migraine in this population approaches 15%, and typically the symptoms continue through adulthood. Hormonal changes associated with puberty and the menstrual cycle may significantly influence migraine in young women. This article reviews the following topics: management of menstrually related headaches, changes in ovarian hormones and their relationship to migraine, and oral contraceptives and pregnancy effects on migraine.

  7. What flowers do we like? The influence of shape and color on the rating of flower beauty.

    Science.gov (United States)

    Hůla, Martin; Flegr, Jaroslav

    2016-01-01

    There is no doubt that people find flowers beautiful. Surprisingly, we know very little about the actual properties which make flowers so appealing to humans. Although the evolutionary aesthetics provides some theories concerning generally preferred flower traits, empirical evidence is largely missing. In this study, we used an online survey in which residents of the Czech Republic (n = 2006) rated the perceived beauty of 52 flower stimuli of diverse shapes and colors. Colored flowers were preferred over their uncolored versions. When controlling for flower shape, we found an unequal preference for different flower colors, blue being the most and yellow the least preferred. In the overall assessment of beauty, shape was more important than color. Prototypical flowers, i.e., radially symmetrical flowers with low complexity, were rated as the most beautiful. We also found a positive effect of sharp flower contours and blue color on the overall rating of flower beauty. The results may serve as a basis for further studies in some areas of the people-plant interaction research.

  8. What flowers do we like? The influence of shape and color on the rating of flower beauty

    Directory of Open Access Journals (Sweden)

    Martin Hůla

    2016-06-01

    Full Text Available There is no doubt that people find flowers beautiful. Surprisingly, we know very little about the actual properties which make flowers so appealing to humans. Although the evolutionary aesthetics provides some theories concerning generally preferred flower traits, empirical evidence is largely missing. In this study, we used an online survey in which residents of the Czech Republic (n = 2006 rated the perceived beauty of 52 flower stimuli of diverse shapes and colors. Colored flowers were preferred over their uncolored versions. When controlling for flower shape, we found an unequal preference for different flower colors, blue being the most and yellow the least preferred. In the overall assessment of beauty, shape was more important than color. Prototypical flowers, i.e., radially symmetrical flowers with low complexity, were rated as the most beautiful. We also found a positive effect of sharp flower contours and blue color on the overall rating of flower beauty. The results may serve as a basis for further studies in some areas of the people-plant interaction research.

  9. Testing hypotheses for excess flower production and low fruit-to-flower ratios in a pollinating seed-consuming mutualism

    Science.gov (United States)

    Holland, J. Nathaniel; Bronstein, Judith L.; DeAngelis, Donald L.

    2004-01-01

    Pollinator attraction, pollen limitation, resource limitation, pollen donation and selective fruit abortion have all been proposed as processes explaining why hermaphroditic plants commonly produce many more flowers than mature fruit. We conducted a series of experiments in Arizona to investigate low fruit-to-flower ratios in senita cacti, which rely exclusively on pollinating seed-consumers. Selective abortion of fruit based on seed predators is of particular interest in this case because plants relying on pollinating seed-consumers are predicted to have such a mechanism to minimize seed loss. Pollinator attraction and pollen dispersal increased with flower number, but fruit set did not, refuting the hypothesis that excess flowers increase fruit set by attracting more pollinators. Fruit set of natural- and hand-pollinated flowers were not different, supporting the resource, rather than pollen, limitation hypothesis. Senita did abort fruit, but not selectively based on pollen quantity, pollen donors, or seed predators. Collectively, these results are consistent with sex allocation theory in that resource allocation to excess flower production can increase pollen dispersal and the male fitness function of flowers, but consequently results in reduced resources available for fruit set. Inconsistent with sex allocation theory, however, fruit production and the female fitness function of flowers may actually increase with flower production. This is because excess flower production lowers pollinator-to-flower ratios and results in fruit abortion, both of which limit the abundance and hence oviposition rates, of pre-dispersal seed predators.

  10. Changes of flowering phenology and flower size in rosaceous plants from a biodiversity hotspot in the past century.

    Science.gov (United States)

    Yu, Qin; Jia, Dong-Rui; Tian, Bin; Yang, Yong-Ping; Duan, Yuan-Wen

    2016-06-17

    Responses of plant traits to climate changes are complex, which could be mirrored by the investigations of herbarium specimens. By examining specimens of Rosa and Cotoneaster species collected since 1920s in Hengduan Mountains, we analyzed the changes of flowering phenology and flower size in the past century when climate changes were considered to be intensified. We found that flowering phenology of Rosa showed no significant change, but flowering phenology of Cotoneaster was delayed in recent years. Flower size of Rosa species showed a marginally significant decrease over the past century. The results suggested that responses of flowering time to global changes and pollinator mediated selection on floral traits might be more complex than what were expected. Our results indicated that future researches based on investigations of herbarium specimens should be carried out on multiple plant species with different flower structures and life histories to better understand the effects of climate changes on plant traits.

  11. Sugars, the clock and transition to flowering

    Directory of Open Access Journals (Sweden)

    Mohammad Reza eBolouri Moghaddam

    2013-02-01

    Full Text Available Sugars do not only act as source of energy, but they also act as signals in plants. This mini review summarizes the emerging links between sucrose-mediated signaling and the cellular networks involved in flowering time control and defense. Cross-talks with gibberellin (GA and jasmonate (JA signaling pathways are highlighted. The circadian clock fulfills a crucial role at the heart of cellular networks and the bilateral relation between sugar signaling and the clock is discussed. It is proposed that important factors controlling plant growth (DELLAs, PIFs, invertases and trehalose- 6-phosphate or T6P might fulfill central roles in the transition to flowering as well. The emerging concept of ‘sweet immunity’, modulated by the clock, might at least partly rely on a sucrose-specific signaling pathway that needs further exploration.

  12. F-box proteins in flowering plants

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In eukaryotes, the ubiquitin-mediated protein degradation pathway has been shown to control several key biological processes such as cell division, development, metabolism and immune response. F-box proteins, as a part of SCF (Skp1-Cullin (or Cdc53)-F-box) complex, functioned by interacting with substrate proteins, leading to their subsequent degradation by the 26S proteasome. To date, several F-box proteins identified in Arabidopsis and Antirrhinum have been shown to play important roles in auxin signal transduction, floral organ formation, flowering and leaf senescence. Arabidopsis genome sequence analysis revealed that it encodes over 1000 predicted F-box proteins accounting for about 5% of total predicted proteins. These results indicate that the ubiquitin-mediated protein degradation involving the F-box proteins is an important mechanism controlling plant gene expression. Here, we review the known F-box proteins and their functionsin flowering plants.

  13. Functional mapping of ontogeny in flowering plants.

    Science.gov (United States)

    Zhao, Xiyang; Tong, Chunfa; Pang, Xiaoming; Wang, Zhong; Guo, Yunqian; Du, Fang; Wu, Rongling

    2012-05-01

    All organisms face the problem of how to perform a sequence of developmental changes and transitions during ontogeny. We revise functional mapping, a statistical model originally derived to map genes that determine developmental dynamics, to take into account the entire process of ontogenetic growth from embryo to adult and from the vegetative to reproductive phase. The revised model provides a framework that reconciles the genetic architecture of development at different stages and elucidates a comprehensive picture of the genetic control mechanisms of growth that change gradually from a simple to a more complex level. We use an annual flowering plant, as an example, to demonstrate our model by which to map genes and their interactions involved in embryo and postembryonic growth. The model provides a useful tool to study the genetic control of ontogenetic growth in flowering plants and any other organisms through proper modifications based on their biological characteristics.

  14. LH (Luteinizing Hormone) Test

    Science.gov (United States)

    ... develop gonads (gonadal agenesis) Chromosomal abnormality, such as Klinefelter syndrome Testicular failure: Viral infection ( mumps ) Trauma Exposure to ... the ovaries or testicles Hormone deficiency Turner syndrome Klinefelter syndrome Chronic infections Cancer Eating disorder (anorexia nervosa) ^ Back ...

  15. Thyroid Hormone Treatment

    Science.gov (United States)

    ... need a different dose of thyroid hormone include birth control pills, estrogen, testosterone, some anti-seizure medications (for ... is no evidence that desiccated thyroid has any advantage over synthetic T4. WHAT ABOUT T3? While most ...

  16. Deciding about hormone therapy

    Science.gov (United States)

    ... your risk for endometrial cancer. Taking progestin with estrogen seems to protect against this cancer. So if you have a ... menopause without taking hormones. They can also help protect your bones, improve your heart health , and help you stay ...

  17. Menopause and Hormones

    Science.gov (United States)

    ... the participating organizations that have assisted in its reproduction and distribution. Learn More about Menopause and Hormones ... Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products

  18. Plants and colour: Flowers and pollination

    Science.gov (United States)

    Miller, Renee; Owens, Simon J.; Rørslett, Bjørn

    2011-03-01

    While there is a range of colours found in plants the predominant colour is green. Pigments in plants have several roles e.g. photosynthesis and signalling. If colour is to be used as a signal then it must stand out from green. However, one should be aware that there are also coloured compounds where we have not yet fully investigated the role of colour in their functions—they may have roles in, for example, defence or heat exchange. In this paper, we will describe the basic chemistry of the major pigments found in plants and especially floral pigments. We will then discuss their locations in parts of the flower (such as sepals, petals, pollen and nectar), the cells in which they are found and their sub-cellular locations. Floral pigments have a large role to play in pollination of flowers by animals. They can and are modified in many ways during the development of flowers in nature, for example, at emergence and post-pollination. There are a range of biochemical mechanisms of colour change both within flowers and in isolated pigments. Some of the factors influencing colour are temperature, co-pigments, pH, metals, sugars, anthocyanin stacking and cell shape. There is a renewed interest in analysing floral pigments and how they are modified partly because of advances in recombinant DNA technologies, but also because of pollinators and their significance to biodiversity and for evolutionary studies. There is continued strong interest from the horticultural industry for the introduction of new colours e.g. the blue rose and for the exploitation of natural dyes. Funding in this area may impact future research in a potentially beneficial way but it must not deflect us from science-based conservation.

  19. Listening to the sound of flower blooming

    Institute of Scientific and Technical Information of China (English)

    YAN; Wei-fang

    2015-01-01

    The most beautiful thing in our life is the first glance,and the most beautiful point of fireworks is its evanescent bloom.Thing’s beautiful is usually due to its evanescent exist.It might exist shortly but in our mind for a long time.As for me,the most beautiful thing is to listen to the sound of flower blooming.

  20. The Exquisite Brushwork of Lotus Flowers

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    Jin Na’s graduation work entitled Lotus Flowers is housed in the collection at the Central Academy of Fine Arts. Jin succeeded in creating a harmonious integral whole which yielded splendid. ambiguous and pleasing visual effects. In recent years. Jin Na has stressed tine relationship of the consciousness of mankind with society and nature. Jin, an exquisite female artist. attempts to express romantic sentiment as obscure dreams.

  1. Fibonacci, quasicrystals and the beauty of flowers.

    Science.gov (United States)

    Gardiner, John

    2012-12-01

    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.

  2. Fibonacci, quasicrystals and the beauty of flowers

    Science.gov (United States)

    Gardiner, John

    2012-01-01

    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

  3. Hormones and female sexuality

    OpenAIRE

    2003-01-01

    Introduction In contrast to animal species in which linear relationships exist between hormonal status and sexual behaviour sexuality in human population is not determined so simply by the level of sexual steroids. The article analyses female sexuality in the light of hormonal status. Administration of sexual steroids during pregnancy and sexual differentiation High doses of gestagens, especially those with high androgen activity, widely used against miscarriages may lead to tomboys, but with...

  4. Hormonal Regulators of Appetite

    OpenAIRE

    Austin Juliana; Marks Daniel

    2008-01-01

    Obesity is a significant cause of morbidity and mortality worldwide. There has been a significant worsening of the obesity epidemic mainly due to alterations in dietary intake and energy expenditure. Alternatively, cachexia, or pathologic weight loss, is a significant problem for individuals with chronic disease. Despite their obvious differences, both processes involve hormones that regulate appetite. These hormones act on specific centers in the brain that affect the sensations of hunger a...

  5. Protein Hormones and Immunity‡

    Science.gov (United States)

    Kelley, Keith W.; Weigent, Douglas A.; Kooijman, Ron

    2007-01-01

    A number of observations and discoveries over the past 20 years support the concept of important physiological interactions between the endocrine and immune systems. The best known pathway for transmission of information from the immune system to the neuroendocrine system is humoral in the form of cytokines, although neural transmission via the afferent vagus is well documented also. In the other direction, efferent signals from the nervous system to the immune system are conveyed by both the neuroendocrine and autonomic nervous systems. Communication is possible because the nervous and immune systems share a common biochemical language involving shared ligands and receptors, including neurotransmitters, neuropeptides, growth factors, neuroendocrine hormones and cytokines. This means that the brain functions as an immune-regulating organ participating in immune responses. A great deal of evidence has accumulated and confirmed that hormones secreted by the neuroendocrine system play an important role in communication and regulation of the cells of the immune system. Among protein hormones, this has been most clearly documented for prolactin (PRL), growth hormone (GH), and insulin-like growth factor-1 (IGF-I), but significant influences on immunity by thyroid stimulating hormone (TSH) have also been demonstrated. Here we review evidence obtained during the past 20 years to clearly demonstrate that neuroendocrine protein hormones influence immunity and that immune processes affect the neuroendocrine system. New findings highlight a previously undiscovered route of communication between the immune and endocrine systems that is now known to occur at the cellular level. This communication system is activated when inflammatory processes induced by proinflammatory cytokines antagonize the function of a variety of hormones, which then causes endocrine resistance in both the periphery and brain. Homeostasis during inflammation is achieved by a balance between cytokines and

  6. Biology of flowering and nectar production in the flowers of the beauty bush (Kolkwitzia amabilis Graebn.

    Directory of Open Access Journals (Sweden)

    Marta Dmitruk

    2012-12-01

    Full Text Available Nectar production and the morphology of the nectary and pollen grains of Kolwitzia amabilis Graebn. were studied during the period 2008–2009 and in 2011. The blooming of beauty bush flowers started in the third decade of May and ended in the middle of June; flowering lasted 22–23 days. The flower life span was 4–5 days. Nectar production began at the bud break stage. The tube of the corolla in beauty bush flowers forms a spur inside which the nectary is located. The secretory surface of the nectary consists of two layers of glandular epidermal outgrowths: unicellular trichomes, with their length ranging 54.6 μm – 70.2 μm, and papillae with a length of 13.0 μm – 20.6 μm. The mean weight of nectar per 10 flowers, determined for the three years of the study, was 8.6 mg, with a sugar concentration of 50.8%. The weight of nectar sugar was on average 4.4 mg. In terms of the size, beauty bush pollen grains are classified as medium-sized. These are tricolporate grains.

  7. Focal Conic Flower Textures at Curved Interfaces

    Directory of Open Access Journals (Sweden)

    Daniel A. Beller

    2013-12-01

    Full Text Available Focal conic domains (FCDs in smectic-A liquid crystals have drawn much attention, both for their exquisitely structured internal form and for their ability to direct the assembly of micromaterials and nanomaterials in a variety of patterns. A key to directing FCD assembly is control over the eccentricity of the domain. Here, we demonstrate a new paradigm for creating spatially varying FCD eccentricity by confining a hybrid-aligned smectic with curved interfaces. In particular, we manipulate interface behavior with colloidal particles in order to experimentally produce two examples of what has recently been dubbed the flower texture [C. Meyer et al., Focal Conic Stacking in Smectic A Liquid Crystals: Smectic Flower and Apollonius Tiling, Materials 2, 499, 2009MATEG91996-194410.3390/ma2020499], where the focal hyperbolæ diverge radially outward from the center of the texture, rather than inward as in the canonical éventail or fan texture. We explain how this unconventional assembly can arise from appropriately curved interfaces. Finally, we present a model for this system that applies the law of corresponding cones, showing how FCDs may be embedded smoothly within a “background texture” of large FCDs and concentric spherical layers, in a manner consistent with the qualitative features of the smectic flower. Such understanding could potentially lead to disruptive liquid-crystal technologies beyond displays, including patterning, smart surfaces, microlens arrays, sensors, and nanomanufacturing.

  8. Is the flower fluorescence relevant in biocommunication?

    Science.gov (United States)

    Iriel, Analía; Lagorio, María Gabriela

    2010-10-01

    Flower fluorescence has been previously proposed as a potential visual signal to attract pollinators. In this work, this point was addressed by quantitatively measuring the fluorescence quantum yield ( Φ 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 yellow), Antirrhinum majus (white and yellow), Eustoma grandiflorum (white and blue), Citrus aurantium (petals and stigma), and Portulaca grandiflora (yellow). The highest values were obtained for the ovaries of O. thyrsoides ( Φ f = 0.030) and for Citrus aurantium petals ( Φ f = 0.014) and stigma ( Φ f = 0.013). Emitted photons as fluorescence were compared with reflected photons. It was concluded that the fluorescence emission is negligible compared to the reflected light, even for the most fluorescent samples, and it may not be considered as an optical signal in biocommunication. The work was complemented with the calculation of quantum catches for each studied flower species to describe the visual sensitization of eye photoreceptors.

  9. Molecular aspects of flower development in grasses.

    Science.gov (United States)

    Ciaffi, Mario; Paolacci, Anna Rita; Tanzarella, Oronzo Antonio; Porceddu, Enrico

    2011-12-01

    The grass family (Poaceae) of the monocotyledons includes about 10,000 species and represents one of the most important taxa among angiosperms. Their flower morphology is remarkably different from those of other monocotyledons and higher eudicots. The peculiar floral structure of grasses is the floret, which contains carpels and stamens, like eudicots, but lacks petals and sepals. The reproductive organs are surrounded by two lodicules, which correspond to eudicot petals, and by a palea and lemma, whose correspondence to eudicot organs remains controversial. The molecular and genetic analysis of floral morphogenesis and organ specification, primarily performed in eudicot model species, led to the ABCDE model of flower development. Several genes required for floral development in grasses correspond to class A, B, C, D, and E genes of eudicots, but others appear to have unique and diversified functions. In this paper, we outline the present knowledge on the evolution and diversification of grass genes encoding MIKC-type MADS-box transcription factors, based on information derived from studies in rice, maize, and wheat. Moreover, we review recent advances in studying the genes involved in the control of flower development and the extent of structural and functional conservation of these genes between grasses and eudicots.

  10. Evolutionary diversification of the flowers in angiosperms.

    Science.gov (United States)

    Endress, Peter K

    2011-03-01

    Angiosperms and their flowers have greatly diversified into an overwhelming array of forms in the past 135 million years. Diversification was shaped by changes in climate and the biological environment (vegetation, interaction with other organisms) and by internal structural constraints and potentials. This review focuses on the development and structural diversity of flowers and structural constraints. It traces floral diversification in the different organs and organ complexes (perianth, androecium, gynoecium) through the major clades of extant angiosperms. The continuously improved results of molecular phylogenetics provide the framework for this endeavor, which is necessary for the understanding of the biology of the angiosperms and their flowers. Diversification appears to work with innovations and modifications of form. Many structural innovations originated in several clades and in special cases could become key innovations, which likely were hot spots of diversification. Synorganization between organs was an important process to reach new structural levels, from which new diversifications originated. Complexity of synorganization reached peaks in Orchidaceae and Apocynaceae with the independent evolution of pollinaria. Such a review throughout the major clades of angiosperms also shows how superficial and fragmentary our knowledge on floral structure in many clades is. Fresh studies and a multidisciplinary approach are needed.

  11. The colorful language of Australian flowers.

    Science.gov (United States)

    Burd, Martin; Stayton, C Tristan; Shrestha, Mani; Dyer, Adrian G

    2014-01-01

    The enormous increase in phylogenetic information in recent years has allowed many old questions to be reexamined from a macroevolutionary perspective. We have recently considered evolutionary convergence in floral colors within pollination syndromes, using bird-pollinated species in Australia. We combined quantitative measurements of floral reflectance spectra, models of avian color vision, and a phylogenetic tree of 234 Australian species to show that bird-pollinated flowers as a group do not have colors that are significantly different from the colors of insect-pollinated flowers. However, about half the bird-pollinated flowers have convergently evolved a narrow range of colors with dominant long-wavelength reflection far more often than would be expected by chance. These convergent colors would be seen as distinctly different from other floral colors in our sample when viewed by honeyeaters (family Meliphagidae), birds with a phylogenetically ancestral type of color vision and the dominant avian pollinators in Australia. Our analysis shows how qualitative ideas in natural history, like the concept of pollination syndromes, can be given more precise definition and rigorous statistical testing that takes into account phylogenetic information.

  12. Flower Bud Differentiation in Quercus suber L.

    Directory of Open Access Journals (Sweden)

    Maria Carolina Varela

    2016-06-01

    Full Text Available Background and Purpose: Cork oak (Quercus suber L. is one of the most important forest species growing in the Western Mediterranean region. This investigation intends to assess the timing of flowering differentiation of cork oak and contribute to the deepening of the knowledge about the process of the sexual reproduction of the species. Materials and Methods: In 2010 four trees were selected (9, 14, 24, 25 from a plot of 25 trees located at Quinta da Serra, Portugal. A total of 240 buds were collected from these four trees, on three days (8, 14 and 23 March, from 4 branches per tree and 5 positions per branch for the assessment of meristem differentiation. Results: Meristem differentiation analysed on the sampling days revealed there were only vegetative structures by 8 March; a few male and female primordia on 14 March; and fully differentiated reproductive structures on 23 March. Conclusions: Flowering sex determination of cork oak occurs about one month before the flowering onset.

  13. Body segments and growth hormone.

    OpenAIRE

    Bundak, R; Hindmarsh, P C; Brook, C. G.

    1988-01-01

    The effects of human growth hormone treatment for five years on sitting height and subischial leg length of 35 prepubertal children with isolated growth hormone deficiency were investigated. Body segments reacted equally to treatment with human growth hormone; this is important when comparing the effect of growth hormone on the growth of children with skeletal dysplasias or after spinal irradiation.

  14. Treatment with thyroid hormone.

    Science.gov (United States)

    Biondi, Bernadette; Wartofsky, Leonard

    2014-06-01

    Thyroid hormone deficiency can have important repercussions. Treatment with thyroid hormone in replacement doses is essential in patients with hypothyroidism. In this review, we critically discuss the thyroid hormone formulations that are available and approaches to correct replacement therapy with thyroid hormone in primary and central hypothyroidism in different periods of life such as pregnancy, birth, infancy, childhood, and adolescence as well as in adult patients, the elderly, and in patients with comorbidities. Despite the frequent and long term use of l-T4, several studies have documented frequent under- and overtreatment during replacement therapy in hypothyroid patients. We assess the factors determining l-T4 requirements (sex, age, gender, menstrual status, body weight, and lean body mass), the major causes of failure to achieve optimal serum TSH levels in undertreated patients (poor patient compliance, timing of l-T4 administration, interferences with absorption, gastrointestinal diseases, and drugs), and the adverse consequences of unintentional TSH suppression in overtreated patients. Opinions differ regarding the treatment of mild thyroid hormone deficiency, and we examine the recent evidence favoring treatment of this condition. New data suggesting that combined therapy with T3 and T4 could be indicated in some patients with hypothyroidism are assessed, and the indications for TSH suppression with l-T4 in patients with euthyroid multinodular goiter and in those with differentiated thyroid cancer are reviewed. Lastly, we address the potential use of thyroid hormones or their analogs in obese patients and in severe cardiac diseases, dyslipidemia, and nonthyroidal illnesses.

  15. Lichens promote flowering Opuntia fragilis in west-central Wisconsin

    Science.gov (United States)

    Bennett, J.P.; Bornar, C.R.; Harrington, C.A.

    2003-01-01

    Clumps of the cactus Opuntia fragilis growing in association with mats of the lichens Cladina mitis, Cladina rangiferina and a spikemoss, Selaginella rupestris, were discovered in an agricultural field in Pepin County, Wisconsin, that had been abandoned for over 50 y. The association appeared to be beneficial to the cactus, which flowered almost exclusively in the presence of lichens. Of 294 cactus clumps examined in 2001, 127 grew in the presence of lichen mats and, of these, 24 flowered, producing 91 flowers, while none of the cacti growing in the absence of lichens flowered. In 2002, 19 out of 265 cactus clumps flowered, all but one in the presence of lichens. All sizes of cacti in the presence of lichens flowered and the probability of flowering increased with cactus size. In addition, the cacti that flowered had cladodes that were on average 19% heavier than those of cacti that did not flower. The presence of lichens lowered summer soil temperatures 2a??4 C compared to soil temperatures in the absence of lichens. Cooler soil temperatures conserve soil moisture better, which may enhance flowering in these cacti.

  16. Development and countermeasures of flower industry in Yunnan, China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Yunan has attracted great attention from the world for its ideal location, advantaged climatic condition, rich biological resources and cheap labor forces. All these advantaged conditions make Yunnan become one of the most potential places in the world for flower production and trade. In recent wars, more and more foreign companies from different countries have forestalled their facilities in Yunnan, joining in the development process of Yunnan floriculture industry. The flower industry in Yunnan Province started to develop towards the end of the 1980s. Flower was only planted one hectare output totaled 35,000 yuan, and the planting area of the flower had 17,000ha and the sales volume of the flowers had 6 billion yuan in 2006. Yunnan Province accounts for 50% of the nation's total cut flower production. Yunnan's. flower industry, has become Asia's largest fresh, cut flower production and export base and sprout breeding and production base. And it has stepped into one of the major flesh-cut flower production areas in the world and a modern flower trading center that is leading in China.

  17. The Solanum lycopersicum auxin response factor SlARF2 participates in regulating lateral root formation and flower organ senescence.

    Science.gov (United States)

    Ren, Zhenxin; Liu, Ruiyuan; Gu, Wenting; Dong, Xicun

    2017-03-01

    ARF2 as apleiotropic developmental regulator has been reported in Arabidopsis thaliana and tomato (Solanum lycopersicum). The present study showed SlARF2 transcripts in all tomato plant tissues but with higher accumulation in flowers. During bud-anthesis stages, SlARF2 transcripts showed a dynamic expression pattern in sepal, stamen, ovary and petal. Hormone treatment analysis suggested that SlARF2 transcript accumulation was positively regulated by auxin and gibberellic acid, and negatively regulated by ethylene in tomato seedlings. Phenotypes and molecular analyses of SlARF2-upregulated transgenic tomato indicated that SlARF2 regulated tomato lateral root formation and flower organ senescence may be partially mediated by regulating the gene expression of auxin and ethylene response factors. The data enlarges the functional characterization of SlARF2 in tomato, and broadens our understanding of auxin signaling in regulating plant growth and development. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Hormonal interactions and gene regulation can link monoecy and environmental plasticity to the evolution of dioecy in plants.

    Science.gov (United States)

    Golenberg, Edward M; West, Nicholas W

    2013-06-01

    Most models for dioecy in flowering plants assume that dioecy arises directly from hermaphroditism through a series of independent feminizing and masculinizing mutations that become chromosomally linked. However, dioecy appears to evolve most frequently through monoecious grades. The major genetic models do not explain the evolution of unisexual flowers in monoecious and submonoecious populations, nor do they account for environmentally induced sexual plasticity. In this review, we explore the roles of environmental stress and hormones on sex determination, and propose a model that can explain the evolution of dioecy through monoecy, and the mechanisms of environmental sex determination. Environmental stresses elicit hormones that allow plants to mediate the negative effects of the stresses. Many of these same hormones are involved in the regulation of floral developmental genes. Recent studies have elucidated the mechanisms whereby these hormones interact and can act as switchpoints in regulatory pathways. Consequently, differential concentrations of plant hormones can regulate whole developmental pathways, providing a mechanism for differential development within isogenic individuals such as seen in monoecious plants. Sex-determining genes in such systems will evolve to generate clusters of coexpressed suites. Coexpression rather than coinheritance of gender-specific genes will define the sexual developmental fate. Therefore, selection for gender type will drive evolution of the regulatory sequences of such genes rather than their synteny. Subsequent mutations to hyper- or hyposensitive alleles within the hormone response pathway can result in segregating dioecious populations. Simultaneously, such developmental systems will remain sensitive to external stimuli that modify hormone responses.

  19. ABSCISIC ACID-INSENSITIVE 4 negatively regulates flowering through directly promoting Arabidopsis FLOWERING LOCUS C transcription

    Science.gov (United States)

    Shu, Kai; Chen, Qian; Wu, Yaorong; Liu, Ruijun; Zhang, Huawei; Wang, Shengfu; Tang, Sanyuan; Yang, Wenyu; Xie, Qi

    2016-01-01

    During the life cycle of a plant, one of the major biological processes is the transition from the vegetative to the reproductive stage. In Arabidopsis, flowering time is precisely controlled by extensive environmental and internal cues. Gibberellins (GAs) promote flowering, while abscisic acid (ABA) is considered as a flowering suppressor. However, the detailed mechanism through which ABA inhibits the floral transition is poorly understood. Here, we report that ABSCISIC ACID-INSENSITIVE 4 (ABI4), a key component in the ABA signalling pathway, negatively regulates floral transition by directly promoting FLOWERING LOCUS C (FLC) transcription. The abi4 mutant showed the early flowering phenotype whereas ABI4-overexpressing (OE-ABI4) plants had delayed floral transition. Consistently, quantitative reverse transcription–PCR (qRT–PCR) assay revealed that the FLC transcription level was down-regulated in abi4, but up-regulated in OE-ABI4. The change in FT level was consistent with the pattern of FLC expression. Chromatin immunoprecipitation-qPCR (ChIP-qPCR), electrophoretic mobility shift assay (EMSA), and tobacco transient expression analysis showed that ABI4 promotes FLC expression by directly binding to its promoter. Genetic analysis demonstrated that OE-ABI4::flc-3 could not alter the flc-3 phenotype. OE-FLC::abi4 showed a markedly delayed flowering phenotype, which mimicked OE-FLC::WT, and suggested that ABI4 acts upstream of FLC in the same genetic pathway. Taken together, these findings suggest that ABA inhibits the floral transition by activating FLC transcription through ABI4. PMID:26507894

  20. A Factor Linking Floral Organ Identity and Growth Revealed by Characterization of the Tomato Mutant unfinished flower development (ufd).

    Science.gov (United States)

    Poyatos-Pertíñez, Sandra; Quinet, Muriel; Ortíz-Atienza, Ana; Yuste-Lisbona, Fernando J; Pons, Clara; Giménez, Estela; Angosto, Trinidad; Granell, Antonio; Capel, Juan; Lozano, Rafael

    2016-01-01

    Floral organogenesis requires coordinated interactions between genes specifying floral organ identity and those regulating growth and size of developing floral organs. With the aim to isolate regulatory genes linking both developmental processes (i.e., floral organ identity and growth) in the tomato model species, a novel mutant altered in the formation of floral organs was further characterized. Under normal growth conditions, floral organ primordia of mutant plants were correctly initiated, however, they were unable to complete their development impeding the formation of mature and fertile flowers. Thus, the growth of floral buds was blocked at an early stage of development; therefore, we named this mutant as unfinished flower development (ufd). Genetic analysis performed in a segregating population of 543 plants showed that the abnormal phenotype was controlled by a single recessive mutation. Global gene expression analysis confirmed that several MADS-box genes regulating floral identity as well as other genes participating in cell division and different hormonal pathways were affected in their expression patterns in ufd mutant plants. Moreover, ufd mutant inflorescences showed higher hormone contents, particularly ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) and strigol compared to wild type. Such results indicate that UFD may have a key function as positive regulator of the development of floral primordia once they have been initiated in the four floral whorls. This function should be performed by affecting the expression of floral organ identity and growth genes, together with hormonal signaling pathways.

  1. A factor linking floral organ identity and growth revealed by characterization of the tomato mutant unfinished flower development (ufd

    Directory of Open Access Journals (Sweden)

    Sandra Poyatos-Pertíñez

    2016-11-01

    Full Text Available Floral organogenesis requires coordinated interactions between genes specifying floral organ identity and those regulating growth and size of developing floral organs. With the aim to isolate regulatory genes linking both developmental processes (i.e. floral organ identity and growth in the tomato model species, a novel mutant altered in the formation of floral organs was further characterized. Under normal growth conditions, floral organ primordia of mutant plants were correctly initiated, however, they were unable to complete their development impeding the formation of mature and fertile flowers. Thus, the growth of floral buds was blocked at an early stage of development; therefore, we named this mutant as unfinished flower development (ufd. Genetic analysis performed in a segregating population of 543 plants showed that the abnormal phenotype was controlled by a single recessive mutation. Global gene expression analysis confirmed that several MADS-box genes regulating floral identity as well as other genes participating in cell division and different hormonal pathways were affected in their expression patterns in ufd mutant plants. Moreover, ufd mutant inflorescences showed higher hormone contents, particularly ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC and strigol compared to wild type. Such results indicate that UFD may have a key function as positive regulator of the development of floral primordia once they have been initiated in the four floral whorls. This function should be performed by affecting the expression of floral organ identity and growth genes, together with hormonal signalling pathways.

  2. Control of the first flowering in forest trees

    Energy Technology Data Exchange (ETDEWEB)

    Chalupka, W. [Inst. od Dendrology, Kornik (Poland); Cecich, R.A. [U.S.D.A.-Forest Service, Columbia, MO (United States). North Central Forest Experiment Station

    1997-04-01

    Precocious flowering provides opportunities to shorten a breeding cycle. A tree may flower for the first time when sufficient crown development has occurred and there are enough meristems to support both vegetative and reproductive buds. Precocious flowering can be promoted through the use of cultural techniques, such as photoperiod, accelerated growth, gibberellins and water stress. The length of the juvenile phase is dependent on genetic and environmental variables that affect achievement of a minimum size, and is positively correlated with the height of the plants within a family. Selection pressure can be applied successfully to the precocious flowering character, and crossed or inbred lines of precocious flowering progeny can be developed. Various levels and amounts of genetic control have been implicated in the control of precocious flowering. 90 refs, 1 tab

  3. Growth hormone response to growth hormone-releasing peptide-2 in growth hormone-deficient Little mice

    OpenAIRE

    PERONI, CIBELE N.; Cesar Y. Hayashida; Nancy Nascimento; LONGUINI, VIVIANE C.; Toledo, Rodrigo A.; Paolo Bartolini; Bowers, Cyril Y.; Toledo,Sergio P. A.

    2012-01-01

    OBJECTIVE: To investigate a possible direct, growth hormone-releasing, hormone-independent action of a growth hormone secretagogue, GHRP-2, in pituitary somatotroph cells in the presence of inactive growth hormone-releasing hormone receptors. MATERIALS AND METHODS: The responses of serum growth hormone to acutely injected growth hormone-releasing P-2 in lit/litmice, which represent a model of GH deficiency arising frommutated growth hormone-releasing hormone-receptors, were compared to those ...

  4. THE USE OF A FLOWERING STABILITY INDEX FOR BIOCUMATIC RESEARCH

    Directory of Open Access Journals (Sweden)

    G. BASSI

    1996-01-01

    Full Text Available Finlay and Wilkinson analysis was used to study the stability, over 21 years. of the beginning of flowering of 53 species. This approach allows to study the behaviour of a siegle species in respect to the average behaviour of all species. Twenty-one out of 25 docile species are sensitive, while the remaining 4 are docile (their beginning of flowering time was relatively constant. The 28 recalcitrant species are characterized by unpredictability in Lbe beginning of flowering time.

  5. Goethe and the ABC model of flower development.

    Science.gov (United States)

    Coen, E

    2001-06-01

    About 10 years ago, the ABC model for the genetic control of flower development was proposed. This model was initially based on the analysis of mutant flowers but has subsequently been confirmed by molecular analysis. This paper describes the 200-year history behind this model, from the late 18th century when Goethe arrived at his idea of plant metamorphosis, to the genetic studies on flower mutants carried out on Arabidopsis and Antirrhinum in the late 20th century.

  6. Flowering phenology: An example of relaxation of natural selection?

    Science.gov (United States)

    Ollerton, J; Lack, A J

    1992-08-01

    Flowering phenology has normally been viewed as fundamental to a plant species' reproductive ecology. Researchers in the field have emphasized the adaptive importance of flowering at a particular time relative to other individuals in the population, or other species in the community. An alternative view, however, is that flowering phenology is a trait that may not be under strong selection, and this may have allowed some variation to appear in populations by chance. Copyright © 1992. Published by Elsevier Ltd.

  7. Pharmacognostical Studies on Flower of Tribulus terrestris L.

    Directory of Open Access Journals (Sweden)

    Mamdouh N. Samy

    2013-01-01

    Full Text Available Tribulus terrestris L. (family Zygophyllaceae is a prostrate branched herb. The stems have monopodial branching and carry opposite compound paripinnate leaves and yellow simple flowers. The fruit is schizocarpic. The present paper deals with comprehensive pharmacognostical studies on flower part of this plant, including macroscopical and microscopical studies of flower. This will help in the identification of powder drug prior using in any herbal formulations.

  8. Endogenous auxin regulates the sensitivity of Dendrobium (cv. Miss Teen) flower pedicel abscission to ethylene

    NARCIS (Netherlands)

    Rungruchkanont, K.; Ketsa, S.; Chatchawankanphanich, O.; Doorn, van W.G.

    2007-01-01

    Dendrobium flower buds and flowers have an abscission zone at the base of the pedicel (flower stalk). Ethylene treatment of cv. Miss Teen inflorescences induced high rates of abscission in flower buds but did not affect abscission once the flowers had opened. It is not known if auxin is a regulator

  9. Endogenous auxin regulates the sensitivity of Dendrobium (cv. Miss Teen) flower pedicel abscission to ethylene

    NARCIS (Netherlands)

    Rungruchkanont, K.; Ketsa, S.; Chatchawankanphanich, O.; Doorn, van W.G.

    2007-01-01

    Dendrobium flower buds and flowers have an abscission zone at the base of the pedicel (flower stalk). Ethylene treatment of cv. Miss Teen inflorescences induced high rates of abscission in flower buds but did not affect abscission once the flowers had opened. It is not known if auxin is a regulator

  10. Assessment of the internal quality of stored flower bulbs using magnetic resonance imaging

    NARCIS (Netherlands)

    Kilsdonk, Maria Gerarda van

    2002-01-01

    Many flower bulbs have a life cycle of a year or more, flowering either in spring or in summer. Nevertheless, year-round production of cut flowers has become common practice in horticulture. To control flowering, which is necessary for the year-round production of flowers, bulbs are exposed to

  11. Headache And Hormones

    Directory of Open Access Journals (Sweden)

    Shukla Rakesh

    2002-01-01

    Full Text Available There are many reasons to suggest a link between headache and hormones. Migraine is three times common in women as compared to men after puberty, cyclic as well as non-cyclic fluctuations in sex hormone levels during the entire reproductive life span of a women are associated with changes in frequency or severity of migraine attack, abnormalities in the hypothalamus and pineal gland have been observed in cluster headache, oestrogens are useful in the treatment of menstrual migraine and the use of melatonin has been reported in various types of primary headaches. Headache associated with various endocrinological disorders may help us in a better understanding of the nociceptive mechanisms involved in headache disorders. Prospective studies using headache diaries to record the attacks of headache and menstrual cycle have clarified some of the myths associated with menstrual migraine. Although no change in the absolute levels of sex hormones have been reported, oestrogen withdrawal is the most likely trigger of the attacks. Prostaglandins, melatonin, opioid and serotonergic mechanisms may also have a role in the pathogenesis of menstrual migraine. Guidelines have been published by the IHS recently regarding the use of oral contraceptives by women with migraine and the risk of ischaemic strokes in migraineurs on hormone replacement therapy. The present review includes menstrual migraine, pregnancy and migraine, oral contraceptives and migraine, menopause and migraine as well as the hormonal changes in chronic migraine.

  12. Hormonal control of euryhalinity

    Science.gov (United States)

    Takei, Yoshio; McCormick, Stephen D.; McCormick, Stephen D.; Farrell, Anthony Peter; Brauner, Colin J.

    2013-01-01

    Hormones play a critical role in maintaining body fluid balance in euryhaline fishes during changes in environmental salinity. The neuroendocrine axis senses osmotic and ionic changes, then signals and coordinates tissue-specific responses to regulate water and ion fluxes. Rapid-acting hormones, e.g. angiotensins, cope with immediate challenges by controlling drinking rate and the activity of ion transporters in the gill, gut, and kidney. Slow-acting hormones, e.g. prolactin and growth hormone/insulin-like growth factor-1, reorganize the body for long-term acclimation by altering the abundance of ion transporters and through cell proliferation and differentiation of ionocytes and other osmoregulatory cells. Euryhaline species exist in all groups of fish, including cyclostomes, and cartilaginous and teleost fishes. The diverse strategies for responding to changes in salinity have led to differential regulation and tissue-specific effects of hormones. Combining traditional physiological approaches with genomic, transcriptomic, and proteomic analyses will elucidate the patterns and diversity of the endocrine control of euryhalinity.

  13. 'Who's who' in two different flower types of Calluna vulgaris (Ericaceae: morphological and molecular analyses of flower organ identity

    Directory of Open Access Journals (Sweden)

    Krüger Katja

    2009-12-01

    Full Text Available Abstract Background The ornamental crop Calluna vulgaris is of increasing importance to the horticultural industry in the northern hemisphere due to a flower organ mutation: the flowers of the 'bud-flowering' phenotype remain closed i.e. as buds throughout the total flowering period and thereby maintain more colorful flowers for a longer period of time than the wild-type. This feature is accompanied and presumably caused by the complete lack of stamens. Descriptions of this botanical particularity are inconsistent and partially conflicting. In order to clarify basic questions of flower organ identity in general and stamen loss in detail, a study of the wild-type and the 'bud-flowering' flower type of C. vulgaris was initiated. Results Flowers were examined by macro- and microscopic techniques. Organ development was investigated comparatively in both the wild-type and the 'bud-flowering' type by histological analyses. Analysis of epidermal cell surface structure of vegetative tissues and perianth organs using scanning electron microscopy revealed that in wild-type flowers the outer whorls of colored organs may be identified as sepals, while the inner ones may be identified as petals. In the 'bud-flowering' type, two whorls of sepals are directly followed by the gynoecium. Both, petals and stamens, are completely missing in this flower type. The uppermost whorl of green leaves represents bracts in both flower types. In addition, two MADS-box genes (homologs of AP3/DEF and SEP1/2 were identified in C. vulgaris using RACE-PCR. Expression analysis by qRT-PCR was conducted for both genes in leaves, bracts, sepals and petals. These experiments revealed an expression pattern supporting the organ classification based on morphological characteristics. Conclusions Organ identity in both wild-type and 'bud-flowering' C. vulgaris was clarified using a combination of microscopic and molecular methods. Our results for bract, sepal and petal organ identity are

  14. ANTIMICROBIAL ACTIVITY OF ROSA CANINA FLOWERS AGAINST SELECTED MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    Katarína Rovná

    2015-02-01

    Full Text Available Rosa canina flowers were screened against various plant pathogenic microbial strains to study the antimicrobial properties of the plant. Ethanolic and methanolic extracts of flowers were screened applying agar well diffusion method against two Gram-negative bacteria including Escherichia coli CCM 3988 and Pseudomonas aeruginosa CCM 1960 and three microscopic filamentous fungi strains Aspergillus niger, Fusarium culmorum and Alternaria alternata, respectively. The best antimicrobial effect of ethanolic extract of Rosa canina flowers was found against Pseudomonas aeruginosa and the best antimicrobial effect of methanolic extract of Rosa canina flowers was found against Escherichia coli.

  15. Ozone and infection of geranium flowers by Botrytis cinerea

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J.; Feder, W.A.; Perkins, I.

    1970-01-01

    Flowering plants of geranium cultivars were exposed to 0.2, 0.35, and 0.55 ppm ozone for 4-hr periods at 20/sup 0/C in a greenhouse fumigation chamber. Three fully-opened flower heads were sprayed with a spore suspension of Botrytis cinerea at 2000, 1000, or 500 spores/ml immediately before exposure to ozone began. Sterile distilled water was sprayed on noninoculated flower heads. All flowers were examined for evidence of infection 24 hr after the end of the ozone-exposure periods. All flower heads were then removed and placed in wet, loosely tied plastic bags and incubated at 20/sup 0/C for 72 hr, with examination at 24-hr intervals for evidence of infection. Ozone at 0.2 ppm did not injure the plants or prevent or inhibit flower infection by B. cinerea at all inoculum levels. Natural infection also occurred on some noninoculated flowers. Ozone at 0.35 ppm did not injure the plants or prevent infection, but did inhibit pathogenesis at the 500-spore/ml inoculum level and on noninoculated flowers. Ozone at 0.55 ppm caused moderate injury on all plants. Ozone at this level did not prevent infection, but did restrict pathogenesis on all inoculated and noninoculated flowers.

  16. Respiration rate of gamma irradiation carnation cut flowers

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Olivia Kimiko; Wiendl, Frederico Maximiliano [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Todoriki, Setsuko; Nakahara, Kazuhiko; Haysahi, Toru [National Food Research Inst., Ibaraki (Japan)

    1996-07-01

    The present paper presents the CO{sub 2} production of the carnation cut flowers gamma-irradiated with a single dose of 750 Gy. The cut flowers were soaked in preservative solutions, containing germicides or germicides plus 2% sucrose. The irradiation did not change the CO{sub 2} production and did not cause any visible flower damage. The sucrose exogenous supply extended the vase-life of both irradiated and non-irradiated carnations. These results indicated that Nora carnation cut flower can be irradiated with 750 Gy without commercial viability loss and that it is possible to use the radiation to disinfect this fresh product. (author)

  17. Edible flowers — antioxidant activity and impact on cell viability

    National Research Council Canada - National Science Library

    Kucekova, Zdenka; Mlcek, Jiri; Humpolicek, Petr; Rop, Otakar

    2013-01-01

    The phenolic compound composition, antioxidant activity and impact on cell viability of edible flower extracts of Allium schoenoprasum; Bellis perennis; Cichorium intybus; Rumex acetosa; Salvia pratensis; Sambucus nigra...

  18. Suboptimal light conditions influence source-sink metabolism during flowering

    Directory of Open Access Journals (Sweden)

    Annelies eChristiaens

    2016-03-01

    Full Text Available Reliance on carbohydrates during flower forcing was investigated in one early and one late flowering cultivar of azalea (Rhododendron simsii hybrids. Carbohydrate accumulation, invertase activity, and expression of a purported sucrose synthase gene (RsSUS was monitored during flower forcing under suboptimal (natural and optimal (supplemental light light conditions, after a cold treatment (7°C + dark to break flower bud dormancy. Post-production sucrose metabolism and flowering quality was also assessed. Glucose and fructose concentrations and invertase activity increased in petals during flowering, while sucrose decreased. In suboptimal light conditions RsSUS expression in leaves increased as compared to optimal light conditions, indicating that plants in suboptimal light conditions have a strong demand for carbohydrates. However, carbohydrates in leaves were markedly lower in suboptimal light conditions compared to optimal light conditions. This resulted in poor flowering of plants in suboptimal light conditions. Post-production flowering relied on the stored leaf carbon, which could be accumulated under optimal light conditions in the greenhouse. These results show that flower opening in azalea relies on carbohydrates imported from leaves and is source-limiting under suboptimal light conditions.

  19. Sepal phenolic profile during Helleborus niger flower development.

    Science.gov (United States)

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

    2013-11-01

    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. Copyright © 2013 Elsevier GmbH. All rights reserved.

  20. Flowering of Areca catechu in Bogor Botanic Gardens

    Directory of Open Access Journals (Sweden)

    Angga Yudaputra

    2017-02-01

    Full Text Available Areca catechu is a species of palms that widely distributed in Indonesia. This palm has unique characteristics and important roles of a tropical forest ecosystem. Indonesian local tribes used seed of this palm for traditionaly medicinal purposes. Information regarding of flowering of A.catechu is valuabe to support a genetic improvement program. Currently, the flowering information about this palm is still lack, thereby study that related with flowering of A. catechu is important to be conducted. This study aimed to provide information about the flowering of A.catechu species. The observation was started with randomly selection of three individuals A. catechu from the Moluccas island. There were 3 main observations which done in this study, included the observation of flowering phases period, morphological changes of each phases, and the micro-climate factors. Flowering A. catechu was categorized into 4 phases, including initiation, bud towards anthesis, anthesis and young fruit to maturity. Each of flowering phases have a different time. The flowering phases were not directly influenced by micro-climate factors. Trigona laeviceps was the most dominant insect visitor and wind was an abiotic factors that influenced the flowering of A. catechu.

  1. Natural soil microbes alter flowering phenology and the intensity of selection on flowering time in a wild Arabidopsis relative.

    Science.gov (United States)

    Wagner, Maggie R; Lundberg, Derek S; Coleman-Derr, Devin; Tringe, Susannah G; Dangl, Jeffery L; Mitchell-Olds, Thomas

    2014-06-01

    Plant phenology is known to depend on many different environmental variables, but soil microbial communities have rarely been acknowledged as possible drivers of flowering time. Here, we tested separately the effects of four naturally occurring soil microbiomes and their constituent soil chemistries on flowering phenology and reproductive fitness of Boechera stricta, a wild relative of Arabidopsis. Flowering time was sensitive to both microbes and the abiotic properties of different soils; varying soil microbiota also altered patterns of selection on flowering time. Thus, soil microbes potentially contribute to phenotypic plasticity of flowering time and to differential selection observed between habitats. We also describe a method to dissect the microbiome into single axes of variation that can help identify candidate organisms whose abundance in soil correlates with flowering time. This approach is broadly applicable to search for microbial community members that alter biological characteristics of interest.

  2. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers

    Directory of Open Access Journals (Sweden)

    Lehto Kirsi

    2011-04-01

    Full Text Available Abstract Background RNA silencing is used in plants as a major defence mechanism against invasive nucleic acids, such as viruses. Accordingly, plant viruses have evolved to produce counter defensive RNA-silencing suppressors (RSSs. These factors interfere in various ways with the RNA silencing machinery in cells, and thereby disturb the microRNA (miRNA mediated endogene regulation and induce developmental and morphological changes in plants. In this study we have explored these effects using previously characterized transgenic tobacco plants which constitutively express (under CaMV 35S promoter the helper component-proteinase (HC-Pro derived from a potyviral genome. The transcript levels of leaves and flowers of these plants were analysed using microarray techniques (Tobacco 4 × 44 k, Agilent. Results Over expression of HC-Pro RSS induced clear phenotypic changes both in growth rate and in leaf and flower morphology of the tobacco plants. The expression of 748 and 332 genes was significantly changed in the leaves and flowers, respectively, in the HC-Pro expressing transgenic plants. Interestingly, these transcriptome alterations in the HC-Pro expressing tobacco plants were similar as those previously detected in plants infected with ssRNA-viruses. Particularly, many defense-related and hormone-responsive genes (e.g. ethylene responsive transcription factor 1, ERF1 were differentially regulated in these plants. Also the expression of several stress-related genes, and genes related to cell wall modifications, protein processing, transcriptional regulation and photosynthesis were strongly altered. Moreover, genes regulating circadian cycle and flowering time were significantly altered, which may have induced a late flowering phenotype in HC-Pro expressing plants. The results also suggest that photosynthetic oxygen evolution, sugar metabolism and energy levels were significantly changed in these transgenic plants. Transcript levels of S

  3. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers.

    Science.gov (United States)

    Soitamo, Arto J; Jada, Balaji; Lehto, Kirsi

    2011-04-20

    RNA silencing is used in plants as a major defence mechanism against invasive nucleic acids, such as viruses. Accordingly, plant viruses have evolved to produce counter defensive RNA-silencing suppressors (RSSs). These factors interfere in various ways with the RNA silencing machinery in cells, and thereby disturb the microRNA (miRNA) mediated endogene regulation and induce developmental and morphological changes in plants. In this study we have explored these effects using previously characterized transgenic tobacco plants which constitutively express (under CaMV 35S promoter) the helper component-proteinase (HC-Pro) derived from a potyviral genome. The transcript levels of leaves and flowers of these plants were analysed using microarray techniques (Tobacco 4 × 44 k, Agilent). Over expression of HC-Pro RSS induced clear phenotypic changes both in growth rate and in leaf and flower morphology of the tobacco plants. The expression of 748 and 332 genes was significantly changed in the leaves and flowers, respectively, in the HC-Pro expressing transgenic plants. Interestingly, these transcriptome alterations in the HC-Pro expressing tobacco plants were similar as those previously detected in plants infected with ssRNA-viruses. Particularly, many defense-related and hormone-responsive genes (e.g. ethylene responsive transcription factor 1, ERF1) were differentially regulated in these plants. Also the expression of several stress-related genes, and genes related to cell wall modifications, protein processing, transcriptional regulation and photosynthesis were strongly altered. Moreover, genes regulating circadian cycle and flowering time were significantly altered, which may have induced a late flowering phenotype in HC-Pro expressing plants. The results also suggest that photosynthetic oxygen evolution, sugar metabolism and energy levels were significantly changed in these transgenic plants. Transcript levels of S-adenosyl-L-methionine (SAM) were also decreased in

  4. The strength of assortative mating for flowering date and its basis in individual variation in flowering schedule.

    Science.gov (United States)

    Weis, A E; Nardone, E; Fox, G A

    2014-10-01

    Although it has been widely asserted that plants mate assortatively by flowering time, there is virtually no published information on the strength or causes of phenological assortment in natural populations. When strong, assortative mating can accelerate the evolution of plant reproductive phenology through its inflationary effect on genetic variance. We estimated potential assortative mating for flowering date in 31 old-field species in Ontario, Canada. For each species, we constructed a matrix of pairwise mating probabilities from the individual flowering schedules, that is the number of flower deployed on successive dates. The matrix was used to estimate the phenotypic correlation between mates, ρ, for flowering date. We also developed a measure of flowering synchrony within species, S, based upon the eigenstructure of the mating matrix. The mean correlation between pollen recipients and potential donors for flowering date was ρ=0.31 (range: 0.05-0.63). A strong potential for assortative mating was found among species with high variance in flowering date, flowering schedules of short duration and skew towards early flower deployment. Flowering synchrony, S, was negatively correlated with potential assortment (r= -0.49), but we go on to show that although low synchrony is a necessary condition for phenological assortative mating, it may not be sufficient to induce assortment for a given phenological trait. The potential correlation between mates showed no seasonal trend; thus, as climate change imposes selection on phenology through longer growing seasons, spring-flowering species are no more likely to experience an accelerated evolutionary response than summer species.

  5. Flower power? Potential benefits and pitfalls of using (flowering) vegetation for conservation biological control

    NARCIS (Netherlands)

    Wackers, F.L.; Rijn, van P.C.J.; Winkler, K.; Olson, D.

    2007-01-01

    Whereas nectar and pollen provision to predators and parasitoids is often a main objective in pursuing agricultural biodiversity, we generally know little about whether the flowering plant species involved are actually suitable as insect food sources or what their ultimate impact is on biological pe

  6. Flower power? Potential benefits and pitfalls of using (flowering) vegetation for conservation biological control

    NARCIS (Netherlands)

    Wackers, F.L.; Rijn, van P.C.J.; Winkler, K.; Olson, D.

    2006-01-01

    Whereas nectar and pollen provision to predators and parasitoids is a main objective in pursuing agricultural biodiversity, we often know little about whether the flowering plant species involved are actually suitable as insect food sources or about their ultimate impact on biological pest control.

  7. Medicinal flowers. XXX. Eight new glycosides, everlastosides F-M, from the flowers of Helichrysum arenarium.

    Science.gov (United States)

    Morikawa, Toshio; Wang, Li-Bo; Ninomiya, Kiyofumi; Nakamura, Seikou; Matsuda, Hisashi; Muraoka, Osamu; Wu, Li-Jun; Yoshikawa, Masayuki

    2009-08-01

    Eight new glycosides, everlastosides F (1), G (2), H (3), I (4), J (5), K (6), L (7), and M (8), were isolated from the methanolic extract of the flowers of Helichrysum arenarium. Their structures were elucidated on the basis of chemical and physicochemical evidence.

  8. STREPTOCARPUS - FLOWERING POT PLANT - PROPAGATION AND CULTURE

    Directory of Open Access Journals (Sweden)

    Maria CANTOR

    2004-08-01

    Full Text Available In the last years in Romania and throughout the world we assist at diversification of floral plants assortment by introducing new species and cultivars. For this goal, at the University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Floriculture Department we diversified and enriched the collection for indoor plants with a pot species, which decorates by flowers, Streptocarpus x hybridus. In this work are presented the main morphological and biological characteristics, propagation by seeds and vegetative propagation, growth requirements, the main diseases and pests of this species, in order to recommend it for indoor culture.

  9. Stylish lengths: Mate choice in flowers

    Indian Academy of Sciences (India)

    B T Ramesha; M D Yetish; G Ravikanth; K N Ganeshaiah; Jaboury Ghazoul; R Uma Shaanker

    2011-06-01

    The styles of flowers may represent an arena for pollen competition in the race to fertilize ovules. Accordingly, selection should favour a longer ‘race’ to better discriminate among variable pollen by increasing style length. Sampling across a taxonomically diverse range of wild and outcrossed species, we found that the distribution of style lengths within plants were skewed towards longer styles, as predicted. In self-pollinated domesticated species, where discrimination among pollen is less important, we found no such pattern. We conclude that style length is under directional selection towards longer styles as a mechanism for mate choice among pollen of variable quality.

  10. The Early Flowers and Angiosperm Evolution

    DEFF Research Database (Denmark)

    Friis, Else Marie; Crane, P.R.; Pedersen, Kaj Raunsgaard

    of the evolutionary history of flowering plants from their earliest phases in obscurity to their dominance in modern vegetation. The discussion provides comprehensive biological and geological background information, before moving on to summarise the fossil record in detail. Including previously unpublished results...... based on research into Early and Late Cretaceous fossil floras from Europe and North America, the authors draw on direct palaeontological evidence of the pattern of angiosperm evolution through time. Synthesising palaeobotanical data with information from living plants, this unique book explores...

  11. 派诺特的Flower Power

    Institute of Scientific and Technical Information of China (English)

    Stephen Cass

    2013-01-01

    想不通为什么办公室植物一直养不活?想种出完美的玫瑰?将价格为60美元的Flower Power(也来自派诺特公司)插入土中.就可能得到答案。两个叉脚测量电容以及当前水量:叉脚上面的金属凸点测量电阻:

  12. The Early Flowers and Angiosperm Evolution

    DEFF Research Database (Denmark)

    Friis, Else Marie; Crane, P.R.; Pedersen, Kaj Raunsgaard

    The recent discovery of diverse fossil flowers and floral organs in Cretaceous strata has revealed astonishing details about the structural and systematic diversity of early angiosperms. Exploring the rich fossil record that has accumulated over the last three decades, this is a unique study...... based on research into Early and Late Cretaceous fossil floras from Europe and North America, the authors draw on direct palaeontological evidence of the pattern of angiosperm evolution through time. Synthesising palaeobotanical data with information from living plants, this unique book explores...... the latest research in the field, highlighting connections with phylogenetic systematics, structure and the biology of extant angiosperms....

  13. Ovarian hormones and obesity.

    Science.gov (United States)

    Leeners, Brigitte; Geary, Nori; Tobler, Philippe N; Asarian, Lori

    2017-05-01

    Obesity is caused by an imbalance between energy intake, i.e. eating and energy expenditure (EE). Severe obesity is more prevalent in women than men worldwide, and obesity pathophysiology and the resultant obesity-related disease risks differ in women and men. The underlying mechanisms are largely unknown. Pre-clinical and clinical research indicate that ovarian hormones may play a major role. We systematically reviewed the clinical and pre-clinical literature on the effects of ovarian hormones on the physiology of adipose tissue (AT) and the regulation of AT mass by energy intake and EE. Articles in English indexed in PubMed through January 2016 were searched using keywords related to: (i) reproductive hormones, (ii) weight regulation and (iii) central nervous system. We sought to identify emerging research foci with clinical translational potential rather than to provide a comprehensive review. We find that estrogens play a leading role in the causes and consequences of female obesity. With respect to adiposity, estrogens synergize with AT genes to increase gluteofemoral subcutaneous AT mass and decrease central AT mass in reproductive-age women, which leads to protective cardiometabolic effects. Loss of estrogens after menopause, independent of aging, increases total AT mass and decreases lean body mass, so that there is little net effect on body weight. Menopause also partially reverses women's protective AT distribution. These effects can be counteracted by estrogen treatment. With respect to eating, increasing estrogen levels progressively decrease eating during the follicular and peri-ovulatory phases of the menstrual cycle. Progestin levels are associated with eating during the luteal phase, but there does not appear to be a causal relationship. Progestins may increase binge eating and eating stimulated by negative emotional states during the luteal phase. Pre-clinical research indicates that one mechanism for the pre-ovulatory decrease in eating is a

  14. Identification of flowering genes in strawberry, a perennial SD plant

    Directory of Open Access Journals (Sweden)

    Rantanen Marja

    2009-09-01

    Full Text Available Abstract Background We are studying the regulation of flowering in perennial plants by using diploid wild strawberry (Fragaria vesca L. as a model. Wild strawberry is a facultative short-day plant with an obligatory short-day requirement at temperatures above 15°C. At lower temperatures, however, flowering induction occurs irrespective of photoperiod. In addition to short-day genotypes, everbearing forms of wild strawberry are known. In 'Baron Solemacher' recessive alleles of an unknown repressor, SEASONAL FLOWERING LOCUS (SFL, are responsible for continuous flowering habit. Although flower induction has a central effect on the cropping potential, the molecular control of flowering in strawberries has not been studied and the genetic flowering pathways are still poorly understood. The comparison of everbearing and short-day genotypes of wild strawberry could facilitate our understanding of fundamental molecular mechanisms regulating perennial growth cycle in plants. Results We have searched homologs for 118 Arabidopsis flowering time genes from Fragaria by EST sequencing and bioinformatics analysis and identified 66 gene homologs that by sequence similarity, putatively correspond to genes of all known genetic flowering pathways. The expression analysis of 25 selected genes representing various flowering pathways did not reveal large differences between the everbearing and the short-day genotypes. However, putative floral identity and floral integrator genes AP1 and LFY were co-regulated during early floral development. AP1 mRNA was specifically accumulating in the shoot apices of the everbearing genotype, indicating its usability as a marker for floral initiation. Moreover, we showed that flowering induction in everbearing 'Baron Solemacher' and 'Hawaii-4' was inhibited by short-day and low temperature, in contrast to short-day genotypes. Conclusion We have shown that many central genetic components of the flowering pathways in Arabidopsis can

  15. Current trends and future directions in flower development research.

    Science.gov (United States)

    Scutt, Charlie P; Vandenbussche, Michiel

    2014-11-01

    Flowers, the reproductive structures of the approximately 400 000 extant species of flowering plants, exist in a tremendous range of forms and sizes, mainly due to developmental differences involving the number, arrangement, size and form of the floral organs of which they consist. However, this tremendous diversity is underpinned by a surprisingly robust basic floral structure in which a central group of carpels forms on an axis of determinate growth, almost invariably surrounded by two successive zones containing stamens and perianth organs, respectively. Over the last 25 years, remarkable progress has been achieved in describing the molecular mechanisms that control almost all aspects of flower development, from the phase change that initiates flowering to the final production of fruits and seeds. However, this work has been performed almost exclusively in a small number of eudicot model species, chief among which is Arabidopsis thaliana. Studies of flower development must now be extended to a much wider phylogenetic range of flowering plants and, indeed, to their closest living relatives, the gymnosperms. Studies of further, more wide-ranging models should provide insights that, for various reasons, cannot be obtained by studying the major existing models alone. The use of further models should also help to explain how the first flowering plants evolved from an unknown, although presumably gymnosperm-like ancestor, and rapidly diversified to become the largest major plant group and to dominate the terrestrial flora. The benefits for society of a thorough understanding of flower development are self-evident, as human life depends to a large extent on flowering plants and on the fruits and seeds they produce. In this preface to the Special Issue, we introduce eleven articles on flower development, representing work in both established and further models, including gymnosperms. We also present some of our own views on current trends and future directions of the

  16. Honey Bees Avoiding Ant Harassment at Flowers Using Scent Cues.

    Science.gov (United States)

    Sidhu, Sheena C; Wilson Rankin, Erin E

    2016-02-01

    Pollinators require resources throughout the year to maintain healthy populations. Along the urban-natural interface, floral resource availability may be limited especially when the system experiences extreme drought and fire threats. In such areas, succulents, such as Aloe spp., are commonly planted to serve as functional drought-tolerant, fire-protective landscaping, which can also support pollinator populations. However, access to this resource may be restricted by competition from other floral foragers, including invasive pests. We measured free-foraging honey bee (Apis mellifera L.) visitation rate and visitation duration to aloe flowers with and without Argentine ants (Linepithema humile (Mayr)) in a drought-stressed environment and found that bees actively avoided foraging on the ant-occupied flowers. To determine the mechanisms of avoidance, our subsequent experiments assessed visitation in the absence of ants and compared aloe flowers treated with ant pheromone to unmanipulated flowers lacking ant pheromone. Bees approached all flowers equally, but accepted flowers without ants at a higher rate than flowers with ants. Visitation duration also increased twofold on ant-excluded flowers, which suggests that Argentine ants may limit resource acquisition by bees. Honey bees similarly avoided flowers with Argentine ant pheromone and preferentially visited unmanipulated flowers at threefold higher rate. This study demonstrates that honey bees avoid foraging on floral resources with invasive Argentine ants and that bees use ant odors to avoid ant-occupied flowers. Resource limitation by this invasive pest ant may have serious implication for sustaining healthy pollinator populations at the urban-natural interface. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Identification of Mendel's white flower character.

    Science.gov (United States)

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

    2010-10-11

    The 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. We 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 combination of genetic mapping, fast neutron mutant analysis, allelic diversity, transcript quantification and transient expression complementation studies to confirm the identity of the candidates. We have identified the pea genes A and A2. A is 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 donor site that leads to a mis-spliced mRNA with a premature stop codon, and we have identified a second rare mutant allele. The A2 gene encodes a WD40 protein that is part of an evolutionarily conserved regulatory complex.

  18. Identification of Mendel's white flower character.

    Directory of Open Access Journals (Sweden)

    Roger P Hellens

    Full Text Available BACKGROUND: The 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 FINDINGS: We 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 combination of genetic mapping, fast neutron mutant analysis, allelic diversity, transcript quantification and transient expression complementation studies to confirm the identity of the candidates. CONCLUSIONS/SIGNIFICANCE: We have identified the pea genes A and A2. A is 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 donor site that leads to a mis-spliced mRNA with a premature stop codon, and we have identified a second rare mutant allele. The A2 gene encodes a WD40 protein that is part of an evolutionarily conserved regulatory complex.

  19. Hormones and postpartum cardiomyopathy.

    NARCIS (Netherlands)

    Clapp, C.; Thebault, S.C.; Martinez de la Escalera, G.M.

    2007-01-01

    Prolactin, a hormone fundamental for lactation, was recently shown to mediate postpartum cardiomyopathy, a life-threatening disease in late-term and lactating mothers. The detrimental effect of prolactin results from myocardial upregulation of cathepsin-D, which in turn cleaves prolactin to a 16 kDa

  20. Hormonal influences on osteoporosis.

    Science.gov (United States)

    McKenna, M J; Frame, B

    1987-01-26

    Osteoporosis has recently received increased attention in both the medical and lay literature. It is estimated that there are more than one million osteoporosis-related fractures yearly in the United States, which are responsible for between three and four billion dollars in health care expenditures. A discussion of osteoporosis requires consideration of both the physiology and pathophysiology of bone tissue. In a structural sense, bone exists in two forms, the outer compact cortex accounting for 80 percent of total bone volume, and the more porous inner trabecular bone. Bone-forming osteoblasts and bone-resorbing osteoclasts are responsible for the ongoing, life-long process of formation and resorption of bone. Sex hormone deficiency, as well as chronic illness, malnutrition, and childhood immobilization, has deleterious effects on growth and modeling, ultimately reducing peak bone mass and setting the stage for osteoporosis in later life. Estrogen is known to have a protective effect on the female skeleton. The mechanisms of this effect are unknown, although estrogen may protect against parathyroid hormone-mediated bone loss. There may be a particular subset of postmenopausal women who are particularly susceptible to estrogen deficiency. Calcitonin levels, which decrease postmenopausally, return to normal with estrogen; other hormones may also play important roles. Osteoporosis is not the result of a single hormonal deficiency or excess; it must be considered in relation to other pathogenetic and risk factors.

  1. [Adipose tissue hormones].

    Science.gov (United States)

    Haluzík, M; Trachta, P; Haluzíková, D

    2010-10-01

    Adipose tissue had been traditionally considered a passive energy storage site without direct influence on energy homeostasis regulation. This view has been principally changed during early nineties by the discovery of hormonal production of adipose tissue. At present, the list of hormonally active substances of adipose tissue includes more than one hundred factors with paracrine or endocrine activity that play an important role in metabolic, food intake a inflammatory regulations and many other processes. Only minority of adipose tissue-derived hormones is produced exclusively in fat. Most of these factors is primarily put out by other tissues and organs. Adipose tissue-derived hormones are produced not only by adipocytes but also by preadipocytes, immunocompetent and endothelial cells and other cell types residing in fat. This paper summarizes current knowledge about endocrine function of adipose tissue with special respect to its changes in obesity. It also describes its possible role in the ethiopathogenesis of insulin resistance, atherosclerosis and other obesity-related pathologies.

  2. Thyroid hormone deiodination

    NARCIS (Netherlands)

    T.J. Visser (Theo)

    1980-01-01

    textabstractThe enzymatic deiodination of thyroid hormone is an important process since it concerns- among other things- the regulation of thyromimetic activity at the site of the target organ. To understand the mechanism of this regulation it is necessary to have a detailed knowledge of the mode of

  3. Thyroid hormone deiodination

    NARCIS (Netherlands)

    T.J. Visser (Theo)

    1980-01-01

    textabstractThe enzymatic deiodination of thyroid hormone is an important process since it concerns- among other things- the regulation of thyromimetic activity at the site of the target organ. To understand the mechanism of this regulation it is necessary to have a detailed knowledge of the mode of

  4. SHBG (Sex Hormone Binding Globulin)

    Science.gov (United States)

    ... as: Testosterone-estrogen Binding Globulin; TeBG Formal name: Sex Hormone Binding Globulin Related tests: Testosterone , Free Testosterone, ... I should know? How is it used? The sex hormone binding globulin (SHBG) test may be used ...

  5. Hormonal contraception and venous thromboembolism

    DEFF Research Database (Denmark)

    Lidegaard, Øjvind; Milsom, Ian; Geirsson, Reynir Tomas;

    2012-01-01

    New studies about the influence of hormonal contraception on the risk of venous thromboembolism (VTE) have been published.......New studies about the influence of hormonal contraception on the risk of venous thromboembolism (VTE) have been published....

  6. Growth Hormone Deficiency in Adults

    Science.gov (United States)

    ... mass and strength Mild bone loss Thinning skin Sleep problems Decreased exercise performance Decreased energy Decreased well-being, mild depression, or moodiness What are the benefits of growth hormone therapy? Growth hormone treatment involves injections (shots) ...

  7. Luteinizing hormone (LH) blood test

    Science.gov (United States)

    ICSH - blood test; Luteinizing hormone - blood test; Interstitial cell stimulating hormone - blood test ... to temporarily stop medicines that may affect the test results. Be sure to tell your provider about ...

  8. ANALGESIC ACTIVITY OF LEPIDAGATHIS CRISTATA WILLD FLOWER EXTRACTS

    Directory of Open Access Journals (Sweden)

    Purma Aravinda Reddy

    2013-08-01

    Full Text Available Aim of the study was to screen the Lepidagathis cristata Willd, flower extracts for analgesic activity. In the present study the analgesic activity of flower extracts was performed. The methanolic, ethyl acetate, chloroform extracts were prepared and were used for analgesic activity in two dose level of 200 and 400mg/kg body weight in two screening methods, Hot Plate (n=5 and Tail Immersion method (n=5. The flower extracts showed significant analgesic activity. The plant extracts did not exhibit any mortality up to the dose level 4000mg/kg. The methanol, chloroform and ethyl acetate extracts of flower was evaluated for analgesic activity. The flower ethyl acetate extract of Lepidagathis cristata showed 47% and 57.1% activity at 200 and 400mg/kg.b.wt, after 30 min by Eddy’s Hot plate Method respectively. The flower chloroform extract showed 43.7% and 44.7% protection at 200, 400mg/kg respectively. The flower methanol, chloroform and ethyl acetate extracts showed dose dependent analgesic activity in thermal models. The flower ethylacetate extract has maximum analgesic activity with 57.1% (p < 0.001c.

  9. Anatomical investigation of flower of Butea monosperma Lam.

    Directory of Open Access Journals (Sweden)

    Ragunathan Muthuswamy

    2014-01-01

    Full Text Available Background: Butea frondosa Roxb. and Koen. syn. Butea monosperma Lam. (Leguminosae or Fabaceae is a tree grows up to the height of 8 m at the age 50 years. Its flowers are being used in traditional medicine for the treatment of ulcer, inflammation, hepatic disorder, and eye diseases. Aims: The present study was aimed at establishing the microscopic characteristics of flower B. monosperma Lam. Materials and Methods: Histological evaluation of flowers was done using standard procedures. Images of microscopic characters were taken at different magnifications using Nikon Labphoto 2 microscopic Unit. Perkin Elmer 5000 an atomic absorption spectrophotometer was employed for elemental analysis. Results: In the study, microscopic characters of floral parts were investigated in transverse section and the flower powder. The current study reveals the presence of pollen grains, ovary (OV, and trichomes in their flower powder. Different cell components were studied, and their sizes were measured. Elemental analysis showed the presence of Zn 52.2 μg/g and Cu 36.3 μg/g were major contents, whereas Cr, Mn, and Pd were minor contents in dried flower powder. Conclusion: The current study paves the way to provide standard information related to the presence of essential elements in the flower. Microscopic characters of the flower and its quantitative measurement of cell components will help to identify the plant and also help to improvise the existing monograph of B. monosperma in the Ayurvedic pharmacopoeia.

  10. Irreversible commitment to flowering in two mango cultivars

    Science.gov (United States)

    In recent years, the state of Nayarit, Mexico has experienced variations in rainfall distribution and warmer temperatures during the autumn-winter season which have caused erratic flowering of mango. The early-flowering cultivars, such as ‘Ataulfo’, have been less affected than tardy ones such as ‘T...

  11. Organic Flower Bulbs From Holland - Outlook for the French Market

    NARCIS (Netherlands)

    Kamphuis, Elise

    2002-01-01

    The Netherlands is a major exporter of flower bulbs in the world. France is amongst the top10 of the biggest importers of Dutch flower bulbs. However, the growing of bulbs is very damaging to the environment. With the use of 1,5 million kilograms of pesticide and 16 million kilograms of artificial f

  12. Shifts in flowering phenology reshape a subalpine plant community.

    Science.gov (United States)

    CaraDonna, Paul J; Iler, Amy M; Inouye, David W

    2014-04-01

    Phenology--the timing of biological events--is highly sensitive to climate change. However, our general understanding of how phenology responds to climate change is based almost solely on incomplete assessments of phenology (such as first date of flowering) rather than on entire phenological distributions. Using a uniquely comprehensive 39-y flowering phenology dataset from the Colorado Rocky Mountains that contains more than 2 million flower counts, we reveal a diversity of species-level phenological shifts that bring into question the accuracy of previous estimates of long-term phenological change. For 60 species, we show that first, peak, and last flowering rarely shift uniformly and instead usually shift independently of one another, resulting in a diversity of phenological changes through time. Shifts in the timing of first flowering on average overestimate the magnitude of shifts in the timing of peak flowering, fail to predict shifts in the timing of last flowering, and underrepresent the number of species changing phenology in this plant community. Ultimately, this diversity of species-level phenological shifts contributes to altered coflowering patterns within the community, a redistribution of floral abundance across the season, and an expansion of the flowering season by more than I mo during the course of our study period. These results demonstrate the substantial reshaping of ecological communities that can be attributed to shifts in phenology.

  13. 7 CFR 318.13-23 - Cut flowers from Hawaii.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Cut flowers from Hawaii. 318.13-23 Section 318.13-23... SERVICE, DEPARTMENT OF AGRICULTURE STATE OF HAWAII AND TERRITORIES QUARANTINE NOTICES Regulated Articles From Hawaii and the Territories § 318.13-23 Cut flowers from Hawaii. (a) Except for cut blooms and leis...

  14. Organic Flower Bulbs From Holland - Outlook for the French Market

    NARCIS (Netherlands)

    Kamphuis, Elise

    2002-01-01

    The Netherlands is a major exporter of flower bulbs in the world. France is amongst the top10 of the biggest importers of Dutch flower bulbs. However, the growing of bulbs is very damaging to the environment. With the use of 1,5 million kilograms of pesticide and 16 million kilograms of artificial

  15. Flowering and seed dispersal of dwarfmistletoe (Arceuthobium campylopodum in California

    Science.gov (United States)

    Robert F. Scharpf

    1965-01-01

    Under the short growing season of the Sierra Nevada, both flowering and seed dispersal of Arceuthobium campylopodum occurred earlier in the fall and dispersal extended for a shorter duration than at lower elevations and along the coast of California. Also in years of above normal surrmer temperatures, flowering and seed dispersal occurred earlier in...

  16. Opening of Iris flowers is regulated by endogenous auxins

    NARCIS (Netherlands)

    Doorn, van W.G.; Dole, I.; Celikel, F.G.; Harkema, H.

    2013-01-01

    Flower opening in Iris (Iris x hollandica) requires elongation of the pedicel and ovary. This moves the floral bud upwards, thereby allowing the tepals to move laterally. Flower opening is requires with elongation of the pedicel and ovary. In cv. Blue Magic, we investigated the possible role of horm

  17. In Vitro propagation of Jasminum officinale L.: a woody ornamental vine yielding aromatic oil from flowers.

    Science.gov (United States)

    Bhattacharya, Sabita; Bhattacharyya, Sanghamitra

    2010-01-01

    The growing demand for flower extracts in perfume trade can primarily be met by increasing flower production and multiplying planting material. The major commercial aromatic flower yielding plants including Jasminum officinale L., a member of the Family Oleaceae have drawn the attention of a large section of the concerned sectors leading to a thrust upon developing advanced propagation technologies for these floral crops, in addition to conventional nature-dependent agro-techniques. This chapter describes concisely and critically, a protocol developed for in vitro propagation of Jasminum officinale by shoot regeneration from existing as well as newly developed adventitious axillary buds via proper phytohormonal stimulation. To start with nodal segments as explants, March-April is the most ideal time of the year when planting material suitable for in vitro multiplication is abundantly available. Prior to inoculation of explants in the culture medium, special care is needed to reduce microbial contamination by spraying on selected spots of the donor plant with anti-microbial agents 24 h prior to collection; treatment with antiseptic solution after final cleaning and surface sterilization by treating explants with mercuric chloride. Inoculated explants are free from brown leaching from cut ends by two consecutive subcultures within 48 h in MS basal medium. Multiplication of shoots, average 4-5 at each node, takes place in MS medium containing 4.0 mg/L BAP, 0.1 mg/L NAA, and 40 g/L sucrose over a period of 8 weeks. For elongation of regenerated shoots, cultures are transferred to MS medium, supplemented with a single growth hormone, kinetin at 2.0 mg/L. Emergence and elongation of roots from shoot base is facilitated by placing on the notch of a filter paper bridge. The hardened in vitro propagated plants are able to grow normally in soil like other conventionally propagated Jasminum officinale.

  18. Programmed cell death: similarities and differences in animals and plants. A flower paradigm.

    Science.gov (United States)

    Mea, M Della; Serafini-Fracassini, D; Duca, S Del

    2007-08-01

    After an overview of the criteria for the definition of cell death in the animal cell and of its different types of death, a comparative analysis of PCD in the plant cell is reported. The cytological characteristics of the plant cell undergoing PCD are described. The role of plant hormones and growth factors in the regulation of this event is discussed with particular emphasis on PCD activation or prevention by polyamine treatment (doses, timing and developmental stage of the organism) in a Developmental cell death plant model: the Nicotiana tabacum (tobacco) flower corolla. Some of the effects of polyamines might be mediated by transglutaminase catalysis. The activity of this enzyme was examined in different parts of the corolla during its life span showing an acropetal trend parallel to the cell death wave. The location of transglutaminase in some sub-cellular compartments suggests that it exerts different functions in the corolla DCD.

  19. Growth Hormone Deficiency in Children

    Science.gov (United States)

    Fact Sheet Growth Defici H e o n r c m y one in Children What is growth hormone deficiency? Growth hormone deficiency (GHD) is a rare condition in which the body does not make enough growth hormone (GH). GH is made by the pituitary ...

  20. Hormonal Control of Fetal Growth.

    Science.gov (United States)

    Cooke, Paul S.; Nicoll, Charles S.

    1983-01-01

    Summarizes recent research on hormonal control of fetal growth, presenting data obtained using a new method for studying the area. Effects of endocrine ablations and congenital deficiencies, studies of hormone/receptor levels, in-vitro techniques, hormones implicated in promoting fetal growth, problems with existing methodologies, and growth of…

  1. The regulation of seasonal flowering in the Rosaceae.

    Science.gov (United States)

    Kurokura, Takeshi; Mimida, Naozumi; Battey, Nicholas H; Hytönen, Timo

    2013-11-01

    Molecular mechanisms regulating the flowering process have been extensively studied in model annual plants; in perennials, however, understanding of the molecular mechanisms controlling flowering has just started to emerge. Here we review the current state of flowering research in perennial plants of the rose family (Rosaceae), which is one of the most economically important families of horticultural plants. Strawberry (Fragaria spp.), raspberry (Rubus spp.), rose (Rosa spp.), and apple (Malus spp.) are used to illustrate how photoperiod and temperature control seasonal flowering in rosaceous crops. We highlight recent molecular studies which have revealed homologues of terminal flower1 (TFL1) to be major regulators of both the juvenile to adult, and the vegetative to reproductive transitions in various rosaceous species. Additionally, recent advances in understanding of the regulation of TFL1 are discussed.

  2. The ancestral flower of angiosperms and its early diversification

    Science.gov (United States)

    Sauquet, Hervé; von Balthazar, Maria; Magallón, Susana; Doyle, James A.; Endress, Peter K.; Bailes, Emily J.; Barroso de Morais, Erica; Bull-Hereñu, Kester; Carrive, Laetitia; Chartier, Marion; Chomicki, Guillaume; Coiro, Mario; Cornette, Raphaël; El Ottra, Juliana H. L.; Epicoco, Cyril; Foster, Charles S. P.; Jabbour, Florian; Haevermans, Agathe; Haevermans, Thomas; Hernández, Rebeca; Little, Stefan A.; Löfstrand, Stefan; Luna, Javier A.; Massoni, Julien; Nadot, Sophie; Pamperl, Susanne; Prieu, Charlotte; Reyes, Elisabeth; dos Santos, Patrícia; Schoonderwoerd, Kristel M.; Sontag, Susanne; Soulebeau, Anaëlle; Staedler, Yannick; Tschan, Georg F.; Wing-Sze Leung, Amy; Schönenberger, Jürg

    2017-01-01

    Recent advances in molecular phylogenetics and a series of important palaeobotanical discoveries have revolutionized our understanding of angiosperm diversification. Yet, the origin and early evolution of their most characteristic feature, the flower, remains poorly understood. In particular, the structure of the ancestral flower of all living angiosperms is still uncertain. Here we report model-based reconstructions for ancestral flowers at the deepest nodes in the phylogeny of angiosperms, using the largest data set of floral traits ever assembled. We reconstruct the ancestral angiosperm flower as bisexual and radially symmetric, with more than two whorls of three separate perianth organs each (undifferentiated tepals), more than two whorls of three separate stamens each, and more than five spirally arranged separate carpels. Although uncertainty remains for some of the characters, our reconstruction allows us to propose a new plausible scenario for the early diversification of flowers, leading to new testable hypotheses for future research on angiosperms. PMID:28763051

  3. Experimental evidence of pollination in marine flowers by invertebrate fauna.

    Science.gov (United States)

    van Tussenbroek, Brigitta I; Villamil, Nora; Márquez-Guzmán, Judith; Wong, Ricardo; Monroy-Velázquez, L Verónica; Solis-Weiss, Vivianne

    2016-09-29

    Pollen transport by water-flow (hydrophily) is a typical, and almost exclusive, adaptation of plants to life in the marine environment. It is thought that, unlike terrestrial environments, animals are not involved in pollination in the sea. The male flowers of the tropical marine angiosperm Thalassia testudinum open-up and release pollen in mucilage at night when invertebrate fauna is active. Here we present experimental evidence that, in the absence of water-flow, these invertebrates visit the flowers, carry and transfer mucilage mass with embedded pollen from the male flowers to the stigmas of the female flowers. Pollen tubes are formed on the stigmas, indicating that pollination is successful. Thus, T. testudinum has mixed abiotic-biotic pollination. We propose a zoobenthophilous pollination syndrome (pollen transfer in the benthic zone by invertebrate animals) which shares many characteristics with hydrophily, but flowers are expected to open-up during the night.

  4. Mechanism of supercooling in flower bud of Camellia oleifea

    Institute of Scientific and Technical Information of China (English)

    苏维埃; 潘良文

    1995-01-01

    It is the first time for MRI to be used in the research of flower buds supercooling. Directobservation on freezing course of living flower buds of Camellia yuhsienensis by MRI and tissue browning test showed that freezing order of the flower organs is bud axis, scale, petal, pistil and stamen. It is coincident with the direction of ice development from bud axes to flower organs upwards. The corresponding results from MRI and freezing-fixation showed that the water translocation from flower organs to axes and scales is carried on in the course of bud freezing. ’H spectral measurement of NMR was used to follow the decrease of unfrozen water in the buds during the cooling.

  5. Pistil Development in 2 Types of Flowers of Xanthoceras sorbifolia

    Institute of Scientific and Technical Information of China (English)

    Hu Qing; Gao Shumin; Li Fenglan

    2004-01-01

    In order to investigate flower development and female abortion during sex differentiation of Xanthoceras sorbifolia, anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporocyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein A1 (14.2 kD) only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion of Xanthoceras sorbifolia.

  6. Flowering phenology, pollen flow and fruit production in the andean shrub Befaria resinosa.

    Science.gov (United States)

    Melampy, M N

    1987-09-01

    In the eastern Andes of Colombia, the shrub Befaria resinosa (Ericaceae) has peaks of flowering that are separated by extended periods of low flower production. The effect that these fluctuations in flower production have on pollen flow was investigated by using fluorescent dye as a pollen analog. Dye applied to open flowers was dispersed over long distances more often during low flower production than during high flower production. Whether enhanced pollen dispersal during flowering lows is of benefit to individual plants is not clear. The proportion of flowers that set fruit is positively correlated with flower abundance, negating the possibility that increased pollen dispersal results in a higher rate of fruit production due to outbreeding effects. It is also difficult to attribute the pattern of fruit production to changes in pollinator visitation rates, which are negatively correlated with flower abundance in the case of hummingbirds and not correlated at all with flower abundance in the case of insects. An opportunistic, large-bodied hummingbird (Colibri coruscans) visits B. resinosa during high flowering and may be a particularly effective pollinator, accounting for some of the increase in the proportion of flowers setting fruit. Rainfall is positively correlated with flower production and may be an important factor in shaping flowering phenology, but it is not significantly correlated with the proportion of flowers setting fruits. The possibility that low-level flowering may counteract inbreeding that results from peak flowering is discussed.

  7. Fertility in barley flowers depends on Jekyll functions in male and female sporophytes.

    Science.gov (United States)

    Radchuk, Volodymyr; Kumlehn, Jochen; Rutten, Twan; Sreenivasulu, Nese; Radchuk, Ruslana; Rolletschek, Hardy; Herrfurth, Cornelia; Feussner, Ivo; Borisjuk, Ljudmilla

    2012-04-01

    • Owing to its evolutional plasticity and adaptability, barley (Hordeum vulgare) is one of the most widespread crops in the world. Despite this evolutionary success, sexual reproduction of small grain cereals is poorly investigated, making discovery of novel genes and functions a challenging priority. Barley gene Jekyll appears to be a key player in grain development; however, its role in flowers has remained unknown. • Here, we studied RNAi lines of barley, where Jekyll expression was repressed to different extents. The impact of Jekyll on flower development was evaluated based on differential gene expression analysis applied to anthers and gynoecia of wildtype and transgenic plants, as well as using isotope labeling experiments, hormone analysis, immunogold- and TUNEL-assays and in situ hybridization. • Jekyll is expressed in nurse tissues mediating gametophyte-sporophyte interaction in anthers and gynoecia, where JEKYLL was found within the intracellular membranes. The repression of Jekyll impaired pollen maturation, anther dehiscence and induced a significant loss of fertility. The presence of JEKYLL on the pollen surface also hints at possible involvement in the fertilization process. • We conclude that the role of Jekyll in cereal sexual reproduction is clearly much broader than has been hitherto realized. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  8. The flavonoid pathway regulates the petal colors of cotton flower.

    Directory of Open Access Journals (Sweden)

    Jiafu Tan

    Full Text Available 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.

  9. Nonrandom Composition of Flower Colors in a Plant Community: Mutually Different Co-Flowering Natives and Disturbance by Aliens.

    Directory of Open Access Journals (Sweden)

    Takashi T Makino

    Full Text Available When pollinators use flower color to locate food sources, a distinct color can serve as a reproductive barrier against co-flowering species. This anti-interference function of flower color may result in a community assembly of plant species displaying mutually different flower colors. However, such color dispersion is not ubiquitous, suggesting a variable selection across communities and existence of some opposing factors. We conducted a 30-week study in a plant community and measured the floral reflectances of 244 species. The reflectances were evaluated in insect color spaces (bees, swallowtails, and flies, and the dispersion was compared with random expectations. We found that co-existing colors were overdispersed for each analyzed pollinator type, and this overdispersion was statistically significant for bees. Furthermore, we showed that exclusion of 32 aliens from the analysis significantly increased the color dispersion of native flowers in every color space. This result indicated that aliens disturbed a native plant-pollinator network via similarly colored flowers. Our results demonstrate the masking effects of aliens in the detection of color dispersion of native flowers and that variations in pollinator vision yield different outcomes. Our results also support the hypothesis that co-flowering species are one of the drivers of color diversification and affect the community assembly.

  10. Modulation of Ambient Temperature-Dependent Flowering in Arabidopsis thaliana by Natural Variation of FLOWERING LOCUS M.

    Directory of Open Access Journals (Sweden)

    Ulrich Lutz

    2015-10-01

    Full Text Available Plants integrate seasonal cues such as temperature and day length to optimally adjust their flowering time to the environment. Compared to the control of flowering before and after winter by the vernalization and day length pathways, mechanisms that delay or promote flowering during a transient cool or warm period, especially during spring, are less well understood. Due to global warming, understanding this ambient temperature pathway has gained increasing importance. In Arabidopsis thaliana, FLOWERING LOCUS M (FLM is a critical flowering regulator of the ambient temperature pathway. FLM is alternatively spliced in a temperature-dependent manner and the two predominant splice variants, FLM-ß and FLM-δ, can repress and activate flowering in the genetic background of the A. thaliana reference accession Columbia-0. The relevance of this regulatory mechanism for the environmental adaptation across the entire range of the species is, however, unknown. Here, we identify insertion polymorphisms in the first intron of FLM as causative for accelerated flowering in many natural A. thaliana accessions, especially in cool (15°C temperatures. We present evidence for a potential adaptive role of this structural variation and link it specifically to changes in the abundance of FLM-ß. Our results may allow predicting flowering in response to ambient temperatures in the Brassicaceae.

  11. WRKY71 accelerates flowering via the direct activation of FLOWERING LOCUS T and LEAFY in Arabidopsis thaliana.

    Science.gov (United States)

    Yu, Yanchong; Liu, Zhenhua; Wang, Long; Kim, Sang-Gyu; Seo, Pil J; Qiao, Meng; Wang, Nan; Li, Shuo; Cao, Xiaofeng; Park, Chung-Mo; Xiang, Fengning

    2016-01-01

    Flowering is crucial for achieving reproductive success. A large number of well-delineated factors affecting flowering are involved in complex genetic networks in Arabidopsis thaliana. However, the underlying part played by the WRKY transcription factors in this process is not yet clear. Here, we report that WRKY71 is able to accelerate flowering in Arabidopsis. An activation-tagged mutant WRKY71-1D and a constitutive over-expresser of WRKY71 both flowered earlier than the wild type (WT). In contrast, both the RNA interference-based multiple WRKY knock-out mutant (w71w8 + 28RNAi) and the dominant repression line (W71-SRDX) flowered later. Gene expression analysis showed that the transcript abundance of the flowering time integrator gene FLOWERING LOCUS T (FT) and the floral meristem identity genes LEAFY (LFY), APETALA1 (AP1) and FRUITFULL (FUL) were greater in WRKY71-1D than in the WT, but lower in w71w8 + 28RNAi and W71-SRDX. Further, WRKY71 was shown to bind to the W-boxes in the FT and LFY promoters in vitro and in vivo. The suggestion is that WRKY71 activity hastens flowering via the direct activation of FT and LFY.

  12. A model describing the flowering of single plants, and the heritability of flowering traits of Dimorphotheca pluvialis

    NARCIS (Netherlands)

    Hof, L.; Keizer, L.C.P.; Elberse, I.A.M.; Dolstra, O.

    1999-01-01

    In the development of new crops such as Dimorphoteca pluvialis (L.) Moench, improvement of flowering synchronisation is an important breeding objective. The flowering of single plants of Dimorphotheca pluvialis could be described by a logistic curve obtained by the regression of cumulative number of

  13. The flowering pattern of Arnica montana L. and A. chamissonis Less. under field cultivation conditions with successive flower head collection

    Directory of Open Access Journals (Sweden)

    Danuta Sugier

    2012-12-01

    Full Text Available The research on the flowering of Arnica montana L. and A. chamissonis Less. was carried out in the years 2005-2006 on two- and three-year plantations on grey-brown podsolic soil with the granulometric composition of heavy clay sand. The aim of the work was to determine the pattern and length of flowering of two- and three-year-old plants under field cultivation conditions with successive flower head collection. The flowering of Arnica montana in both years of study lasted 26 days (from the 28th of May to the 22nd of June. In this period, eight collections of flower heads were made. When analyzing the number of inflorescences gathered during particular collections, it was concluded that at the initial stage of flowering it was not great, but it successively increased with the passage of time up to the seventh collection. The pattern of flowering of the two- and three-year-old Arnica montana plants was similar. The inflorescences of Arnica chamissonis were collected six times, and the most abundant flowering was found in the middle period of this stage, which lasted 20 days.

  14. Biological activities of Juglans regia flowers

    Directory of Open Access Journals (Sweden)

    Seyed Fazel Nabavi

    2011-06-01

    Full Text Available Antidepressant, anti-inflammatory, antihypoxic and antioxidant activities of methanol extract of Juglans regia L., Juglandaceae, flower were investigated. Antidepressant activity was examined by forced swimming test and tail suspension test in mice. Antihypoxic activity was investigated in haemic and circulatory models. The effects were pronounced in both models. It produced statistically significant anti-inflammatory activity in carrageenan induced edema at nearly all doses, compared to control groups. IC50 for DPPH radical-scavenging activity was 674±27.6 µg mL-1. Extract showed good Fe2+ chelating ability (IC50 43±1.5 µg mL-1. It exhibited low antioxidant activity in linoleic acid peroxidation test. Its pharmacological effects may be attributed, in part, to the presence of phenols and ISSN 0102-695X flavonoids in the extract.

  15. Mechanisms of Optimal Defense Patterns in Nicotiana attenuata: Flowering Attenuates Herbivory-elicited Ethylene and Jasmonate Signaling

    Institute of Scientific and Technical Information of China (English)

    Celia Diezel; Silke AIImann; lan T. Baldwin

    2011-01-01

    To defend themselves against herbivore attack,plants produce secondary metabolites,which are variously inducible and constitutively deployed,presumably to optimize their fitness benefits in light of their fitness costs.Three phytohormones,jasmonates (JA) and their active forms,the JA-isoleucine (JA-Ile) and ethylene (ET),are known to play central roles in the elicitation of induced defenses,but little is known about how this mediation changes over ontogeny.The Optimal Defense Theory (ODT) predicts changes in the costs and benefits of the different types of defenses and has been usefully extrapolated to their modes of deployment.Here we studied whether the herbivore-induced accumulation of JA,JA-lle and ET changed over ontogeny in Nicotiana attenuata,a native tobacco in which inducible defenses are particularly well studied.Herbivore-elicited ET production changed dramatically during six developmental stages,from rosette through flowering,decreasing with the elongation of the first corollas during flower development.This decrease was largely recovered within a day after flower removal by decapitation.A similar pattern was found for the herbivore-induced accumulation of JA and JA-IIe.These results are consistent with ODT predictions and suggest that the last steps in floral development control the inducibility of at least three plant hormones,optimizing defense-growth tradeoffs.

  16. Volatile Organic Compounds Emissions from Luculia pinceana Flower and Its Changes at Different Stages of Flower Development.

    Science.gov (United States)

    Li, Yuying; Ma, Hong; Wan, Youming; Li, Taiqiang; Liu, Xiuxian; Sun, Zhenghai; Li, Zhenghong

    2016-04-22

    Luculia plants are famed ornamental plants with sweetly fragrant flowers, of which L. pinceana Hooker, found primarily in Yunnan Province, China, has the widest distribution. Solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) was employed to identify the volatile organic compounds (VOCs) emitted from different flower development stages of L. pinceana for the evaluation of floral volatile polymorphism. Peak areas were normalized as percentages and used to determine the relative amounts of the volatiles. The results showed that a total of 39 compounds were identified at four different stages of L. pinceana flower development, including 26 at the bud stage, 26 at the initial-flowering stage, 32 at the full-flowering stage, and 32 at the end-flowering stage. The most abundant compound was paeonol (51%-83%) followed by (E,E)-α-farnesene, cyclosativene, and δ-cadinene. All these volatile compounds create the unique fragrance of L. pinceana flower. Floral scent emission offered tendency of ascending first and descending in succession, meeting its peak level at the initial-flowering stage. The richest diversity of floral volatile was detected at the third and later periods of flower development. Principal component analysis (PCA) indicated that the composition and its relative content of floral scent differed throughout the whole flower development. The result has important implications for future floral fragrance breeding of Luculia. L. pinceana would be adequate for a beneficial houseplant and has a promising prospect for development as essential oil besides for a fragrant ornamental owing to the main compounds of floral scent with many medicinal properties.

  17. Volatile Organic Compounds Emissions from Luculia pinceana Flower and Its Changes at Different Stages of Flower Development

    Directory of Open Access Journals (Sweden)

    Yuying Li

    2016-04-01

    Full Text Available Luculia plants are famed ornamental plants with sweetly fragrant flowers, of which L. pinceana Hooker, found primarily in Yunnan Province, China, has the widest distribution. Solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS was employed to identify the volatile organic compounds (VOCs emitted from different flower development stages of L. pinceana for the evaluation of floral volatile polymorphism. Peak areas were normalized as percentages and used to determine the relative amounts of the volatiles. The results showed that a total of 39 compounds were identified at four different stages of L. pinceana flower development, including 26 at the bud stage, 26 at the initial-flowering stage, 32 at the full-flowering stage, and 32 at the end-flowering stage. The most abundant compound was paeonol (51%–83% followed by (E,E-α-farnesene, cyclosativene, and δ-cadinene. All these volatile compounds create the unique fragrance of L. pinceana flower. Floral scent emission offered tendency of ascending first and descending in succession, meeting its peak level at the initial-flowering stage. The richest diversity of floral volatile was detected at the third and later periods of flower development. Principal component analysis (PCA indicated that the composition and its relative content of floral scent differed throughout the whole flower development. The result has important implications for future floral fragrance breeding of Luculia. L. pinceana would be adequate for a beneficial houseplant and has a promising prospect for development as essential oil besides for a fragrant ornamental owing to the main compounds of floral scent with many medicinal properties.

  18. Sex Hormones and Tendon

    DEFF Research Database (Denmark)

    Hansen, Mette; Kjaer, Michael

    2016-01-01

    The risk of overuse and traumatic tendon and ligament injuries differ between women and men. Part of this gender difference in injury risk is probably explained by sex hormonal differences which are specifically distinct during the sexual maturation in the teenage years and during young adulthood....... The effects of the separate sex hormones are not fully elucidated. However, in women, the presence of estrogen in contrast to very low estrogen levels may be beneficial during regular loading of the tissue or during recovering after an injury, as estrogen can enhance tendon collagen synthesis rate. Yet...... has also been linked to a reduced responsiveness to relaxin. The present chapter will focus on sex difference in tendon injury risk, tendon morphology and tendon collagen turnover, but also on the specific effects of estrogen and androgens....

  19. Hormones in pregnancy

    Directory of Open Access Journals (Sweden)

    Pratap Kumar

    2012-01-01

    Full Text Available The endocrinology of human pregnancy involves endocrine and metabolic changes that result from physiological alterations at the boundary between mother and fetus. Progesterone and oestrogen have a great role along with other hormones. The controversies of use of progestogen and others are discussed in this chapter. Progesterone has been shown to stimulate the secretion of Th2 and reduces the secretion of Th1 cytokines which maintains pregnancy. Supportive care in early pregnancy is associated with a significant beneficial effect on pregnancy outcome. Prophylactic hormonal supplementation can be recommended for all assisted reproduction techniques cycles. Preterm labor can be prevented by the use of progestogen. The route of administration plays an important role in the drug′s safety and efficacy profile in different trimesters of pregnancy. Thyroid disorders have a great impact on pregnancy outcome and needs to be monitored and treated accordingly. Method of locating review: Pubmed, scopus

  20. Biosimilar growth hormone.

    Science.gov (United States)

    Saenger, Paul

    2012-01-01

    As the first wave of biopharmaceuticals is expiring, biosimilars or follow-on -protein products (FOPP's) have emerged. Biosimilar drugs are cheaper than the originator/comparator drug. The regulatory foundation for these products is more advanced and better codified in Europe than in the US. Biosimilar soamtropin has been approved in both the US and Europe. The scientific viability of biosimilar drugs and especially growth hormone has been proven by several rigorously conducted clinical trials. Efficacy and safety data (growth rates, IGF-1 generation) for up to 7 y for pediatric indications measure up favorably to previously approved growth hormones which served as reference comparators. The Obama Administration appears to be committed to establish innovative pathways for the approval of biologics and biosimilars in the US. The cost savings in health care expenditures will be substantial as the global sales of biologics have reached $ 93 billion in 2009.

  1. Gastrointestinal hormones and their targets

    DEFF Research Database (Denmark)

    Rehfeld, Jens F.

    2014-01-01

    Gastrointestinal hormones are peptides released from endocrine cells and neurons in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gastrointestinal tract, which makes the gut the largest hormone producing organ in the body. Modern biology makes......, paracrine, spermiocrine secretion etc.), so the same peptide may act as a blood-borne hormone, a neurotransmitter, a local growth factor, or a fertility factor. The molecular targets of each bioactive peptide are specific G-protein coupled receptors expressed in the cell membranes of different target cells...... it feasible to conceive the hormones under five headings: The structural homology groups a majority of the hormones into nine families, each of which is assumed to originate from one ancestral gene. The individual hormone gene often has multiple phenotypes due to alternative splicing, tandem organization...

  2. The wound hormone jasmonate

    OpenAIRE

    Koo, Abraham J. K.; Howe, Gregg A.

    2009-01-01

    Plant tissues are highly vulnerable to injury by herbivores, pathogens, mechanical stress, and other environmental insults. Optimal plant fitness in the face of these threats relies on complex signal transduction networks that link damage-associated signals to appropriate changes in metabolism, growth, and development. Many of these wound-induced adaptive responses are triggered by de novo synthesis of the plant hormone jasmonate (JA). Recent studies provide evidence that JA mediates systemic...

  3. Growth Hormone and Aging

    Science.gov (United States)

    2000-08-01

    thru ADP010582 UNCLASSIFIED 23-1 GROWTH HORMONE AND AGING J.A.F. Tresguerres , Perez Romero, N. de las Heras, S. Vazquez, C. Ariznavarreta Complutense... Tresguerres 1996). GHRH is were treated as children with GH, a significant secreted in peaks as well as somatostatin, both number of problems were detected...of GH ( Tresguerres 1996) reduction in muscular and bone mass together IGFI is a peptide of 70 aminoacids that shows with an increase in body fat

  4. Delayed Flowering in Bamboo: Evidence from Fargesia qinlingensis in the Qinling Mountains of China

    Directory of Open Access Journals (Sweden)

    Wei eWang

    2016-02-01

    Full Text Available Gregarious flowering of bamboo species impacts ecosystem properties and conservation, but documentation of these periodic events is difficult. Here, we compare the characteristics of flowering sites and un-flowered patches of an arrow bamboo (Fargesia qinlingensis in the Qinling Mountains, China, over a five-year period (2003-2007 after a mast flowering event (2003. We examined flowering culm and seedling characteristics in relation to questions regarding the evolution of delayed flowering. Density of live culms decreased over the five years in both flowering sites and un-flowered patches. New shoots regenerated only in un-flowered patches. Chemical constituent allocation varied among culm parts (stems, branches, and leaves. Crude protein and extract ether in branches and leaves were less in flowering culms than in un-flowered culms. Seedling density was lower than expected based on floret counts, suggesting predation of seeds. Seedling density was significantly greater in flowering sites than in un-flowered patches and decreased over time. Seedlings performed better in flowering sites than in un-flowered patches based on their height, leaf number per seedling, and average leaf length, while fertilization on flowering sites had no significant effect on seedling growth, suggesting a saturation of resources. This study suggested that the characteristics of bamboos and bamboo stands were dramatically altered during this flowering event, enhancing seedling establishment and growth, and supporting mostly the habitat modification hypothesis of delayed reproduction.

  5. Bees, birds and yellow flowers: pollinator-dependent convergent evolution of UV patterns.

    Science.gov (United States)

    Papiorek, S; Junker, R R; Alves-Dos-Santos, I; Melo, G A R; Amaral-Neto, L P; Sazima, M; Wolowski, M; Freitas, L; Lunau, K

    2016-01-01

    Colour is one of the most obvious advertisements of flowers, and occurs in a huge diversity among the angiosperms. Flower colour is responsible for attraction from a distance, whereas contrasting colour patterns within flowers aid orientation of flower visitors after approaching the flowers. Due to the striking differences in colour vision systems and neural processing across animal taxa, flower colours evoke specific behavioural responses by different flower visitors. We tested whether and how yellow flowers differ in their spectral reflectance depending on the main pollinator. We focused on bees and birds and examined whether the presence or absence of the widespread UV reflectance pattern of yellow flowers predicts the main pollinator. Most bee-pollinated flowers displayed a pattern with UV-absorbing centres and UV-reflecting peripheries, whereas the majority of bird-pollinated flowers are entirely UV- absorbing. In choice experiments we found that bees did not show consistent preferences for any colour or pattern types. However, all tested bee species made their first antennal contact preferably at the UV-absorbing area of the artificial flower, irrespective of its spatial position within the flower. The appearance of UV patterns within flowers is the main difference in spectral reflectance between yellow bee- and bird-pollinated flowers, and affects the foraging behaviour of flower visitors. The results support the hypothesis that flower colours and the visual capabilities of their efficient pollinators are adapted to each other.

  6. [Acne and hormones].

    Science.gov (United States)

    Faure, Michel

    2002-04-15

    Androgens stimulate sebum production which is necessary for the development of acne. Acne in women may thus be considered as a manifestation of cutaneous androgenization. Most of acnes may be related to an idiopathic skin hyperandrogenism due to in situ enzyme activity and androgen receptor hypersensitivity, as also noted in idiopathic hirsutism. Some acne may correspond to elevated ovarian or adrenal androgen secretion. The presence of acne in women may lead to a diagnosis of functional hyperandrogenism, either polycysticovary syndrome or nonclassical 21-hydroxylase deficiency. Plasma level assays for testosterone, delta 4 androstenedione and 17-OH progesterone and ovarian echography are necessary to determine the possibility for an ovarian or adrenal hyperandrogenism, but not to better treat acne. The goal of hormonal therapy in acne is to oppose the effects of androgens on the sebaceous gland. Hormones may be used in female acne in the absence of endocrine abnormalities. Antiandrogens (cyproterone acetate or aldactone) may be useful in severe acne, hormonal contraceptives with cyproterone acetate or non androgenic progestins in mild or common acne often in association with other anti-acneic drugs. Glucocorticoids have to be administered in acne fulminans and other forms of acute, severe, inflammatory acne, for their anti-inflammatory properties.

  7. [Hormones and the cardiovascular system].

    Science.gov (United States)

    Lacka, Katarzyna; Czyzyk, Adam

    2008-01-01

    Hormones have an influence on many tissues and organs, including the cardio-vascular system (CVS). Depending on their activity on CVS, they can be divided into 4 groups: having hypertensive or hypotensive influence and chronotropic positive or negative action. Endocrine regulation in CVS may occur in many ways. Apart from hormones usually connected with CVS regulation, other more recently, discovered ones can act on it. A few of these act directly through specific receptors in heart or vessel wall cells, whereas some act indirectly - stimulating other neuroendocrine factors. Additionally, novel mechanisms of signal transduction have been discovered for steroid and thyroid hormones, which are independent of gene transcription regulation and are - known as "nongenomic". Hormones which increase blood pressure include: urotensin II, endothelins, angiotensin II, catecholamines, aldosterone, antidiuretic hormone, glucocorticosteroids, thyroid hormones, growth hormone and leptin. On the other hand, blood pressure can be decreased by: natriuretic peptides, the calcitonin gene-related peptide (CGRP) family, angiotensin 1-7, substance P, neurokinin A, ghrelin, Parathyroid hormone-related protein (PTHrP), oxytocin, and, sex hormones. Hormones which when appearing in excess increase the heart rate are: catecholamines, endothelins, glucocorticosteroids, thyroid hormones, leptin and PTHrP. Those which decrease the heart rate include: natriuretic peptides, substance P, neurokinin A, oxytocin, angiotensin 1-7. This paper describes the contemporary view of the functions of hormones which act on the vessel tree and heart. The particular effect of mediator depends on many circumstances i.e.: hormone concentration, receptor type. It may also undergo contraregulation. The majority of those hormones play an important role in the pathogenesis of CVS diseases', which can result in the development of new medicines.

  8. A genomic approach to elucidating grass flower development

    Directory of Open Access Journals (Sweden)

    Dornelas Marcelo C.

    2001-01-01

    Full Text Available In sugarcane (Saccharum sp as with other species of grass, at a certain moment of its life cycle the vegetative meristem is converted into an inflorescence meristem which has at least two distinct inflorescence branching steps before the spikelet meristem terminates in the production of a flower (floret. In model dicotyledonous species such successive conversions of meristem identities and the concentric arrangement of floral organs in specific whorls have both been shown to be genetically controlled. Using data from the Sugarcane Expressed Sequence Tag (EST Project (SUCEST database, we have identified all sugarcane proteins and genes putatively involved in reproductive meristem and flower development. Sequence comparisons of known flower-related genes have uncovered conserved evolutionary pathways of flower development and flower pattern formation between dicotyledons and monocotyledons, such as some grass species. We have paid special attention to the analysis of the MADS-box multigene family of transcription factors that together with the APETALA2 (AP2 family are the key elements of the transcriptional networks controlling plant reproductive development. Considerations on the evolutionary developmental genetics of grass flowers and their relation to the ABC homeotic gene activity model of flower development are also presented.

  9. Flowering phenology shifts in response to biodiversity loss

    Science.gov (United States)

    Wolf, Amelia A.; Zavaleta, Erika S; Selmants, Paul C.

    2017-01-01

    Observational studies and experimental evidence agree that rising global temperatures have altered plant phenology—the timing of life events, such as flowering, germination, and leaf-out. Other large-scale global environmental changes, such as nitrogen deposition and altered precipitation regimes, have also been linked to changes in flowering times. Despite our increased understanding of how abiotic factors influence plant phenology, we know very little about how biotic interactions can affect flowering times, a significant knowledge gap given ongoing human-caused alteration of biodiversity and plant community structure at the global scale. We experimentally manipulated plant diversity in a California serpentine grassland and found that many plant species flowered earlier in response to reductions in diversity, with peak flowering date advancing an average of 0.6 days per species lost. These changes in phenology were mediated by the effects of plant diversity on soil surface temperature, available soil N, and soil moisture. Peak flowering dates were also more dispersed among species in high-diversity plots than expected based on monocultures. Our findings illustrate that shifts in plant species composition and diversity can alter the timing and distribution of flowering events, and that these changes to phenology are similar in magnitude to effects induced by climate change. Declining diversity could thus contribute to or exacerbate phenological changes attributed to rising global temperatures.

  10. Nitric oxide participates in plant flowering repression by ascorbate

    Science.gov (United States)

    Senthil Kumar, Rajendran; Shen, Chin-Hui; Wu, Pei-Yin; Suresh Kumar, Subbiah; Hua, Moda Sang; Yeh, Kai-Wun

    2016-01-01

    In Oncidium, redox homeostasis involved in flowering is mainly due to ascorbic acid (AsA). Here, we discovered that Oncidium floral repression is caused by an increase in AsA-mediated NO levels, which is directed by the enzymatic activities of nitrate reductase (NaR) and nitrite reducatase (NiR). Through Solexa transcriptomic analysis of two libraries, ‘pseudobulb with inflorescent bud’ (PIB) and ‘pseudobulb with axillary bud’ (PAB), we identified differentially expressed genes related to NO metabolism. Subsequently, we showed a significant reduction of NaR enzymatic activities and NO levels during bolting and blooming stage, suggesting that NO controlled the phase transition and flowering process. Applying AsA to Oncidium PLB (protocorm-like bodies) significantly elevated the NO content and enzyme activities. Application of sodium nitroprusside (-NO donor) on Arabidopsis vtc1 mutant caused late flowering and expression level of flowering-associated genes (CO, FT and LFY) were reduced, suggesting NO signaling is vital for flowering repression. Conversely, the flowering time of noa1, an Arabidopsis NO-deficient mutant, was not altered after treatment with L-galacturonate, a precursor of AsA, suggesting AsA is required for NO-biosynthesis involved in the NO-mediated flowering-repression pathway. Altogether, Oncidium bolting is tightly regulated by AsA-mediated NO level and downregulation of transcriptional levels of NO metabolism genes. PMID:27731387

  11. Genetic regulation of flowering time in annual and perennial plants.

    Science.gov (United States)

    Khan, Muhammad Rehman Gul; Ai, Xiao-Yan; Zhang, Jin-Zhi

    2014-01-01

    Flowering time plays a significant role in the reproductive success of plants. So far, five major pathways to flowering have been characterized in Arabidopsis, including environmental induction through photoperiod, vernalization, and gibberellins and autonomous floral iation, and aging by sequentially operating miRNAs (typically miR156 and miR172) responding to endogenous cues. The balance of signals from these pathways is integrated by a common set of genes (FLOWERING LOCUS C, FLOWERING LOCUS T, LEAFY, and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1) that determine the flowering time. Recent studies have indicated that epigenetic modification, alternative splicing, antisense RNA and chromatin silencing regulatory mechanisms play an important role in this process by regulating related flowering gene expression. In this review, we discuss the current understanding in genetic regulation of the phase transition from vegetative to reproductive growth by using Arabidopsis as a model. We also describe how this knowledge has been successfully applied for identifying homologous genes from perennial crops. Furthermore, detailed analysis of the similarities and differences between annual and perennial plants flowering will help elucidate the mechanisms of perennial plant maturation and regulation of floral initiation.

  12. Morpho-Anatomical Analysis of Cosmostigma racemosum (Asclepiadoideae Flowers

    Directory of Open Access Journals (Sweden)

    Widodo Widodo

    2014-04-01

    Full Text Available Cosmostigma racemosum is a plant species belonging to the family Apocynaceae, the subfamily Asclepiadoideae. Cosmostigma racemosum is found in Nglanggeran Mountain Gunungkidul, Yogyakarta. The local name and its original distribution are not known. Information or study of Cosmostigma racemosum in Indonesia is not available. Comprehensive characterization of this species is important for authentication and addition of data base. Characterization was conducted by analyzing the morphology and anatomy of flower. The objectives of this study were to describe and analyze the morphology and anatomy of C. racemosum flowers.  The method of research was based on observation method and exploration of plant systematics evidence or taxonomy evidence, including analyses and description of morphology and anatomy of flower structure and its development.  The results showed that the characteristics of flower morphology are in accordance with the existing description in literatures. Characteristics of pollinia are specific characters of morphological aspect of flower. Data of anatomy of flower and its parts development are the new ones which confirm the position of C.racemosum as a member of the tribe Marsdenieae. The data of anatomy also show new information of the ontogeny of the important parts of flower: pollinia formation, pollinia corpusculum, anther wall, anther sac, stigma, stamen, staminal tube, stigmatic chamber, and structure of ovary in Asclepiadoideae

  13. IMPROVING POSTHARVEST VASE-LIFE AND QUALITY OF CUT GERBERA FLOWERS USING NATURAL AND CHEMICAL PRESERVATIVES

    Directory of Open Access Journals (Sweden)

    Mehrdad Jafarpour

    2015-06-01

    Full Text Available Gerbera is one of ten popular cut flowers in the world which occupies the forth place according to the global trends in floriculture. Hence, this study aimed to investigate the effects of chemical, hormonal and essential oil substances in preservative solutions to improve its postharvest qualitative characteristics. Two pulse treatments including distilled water (pulse1 and 4% CaCl2 + 3% sucrose (pulse2 for 24 hour were applied before long-time treatments. Long-time treatments were comprised of (1 Hormonal treatments: 0, 25, 30 mg*l-1 Gibberellic acid, 0, 150, 250 mg*l-1 Benzyl adenine and 0, 100, 200 mg*l-1 5-Sulfosalicylic acid (2 Chemical treatments: 0, 0.4, 0.8 mM Silver thiosulphate, 0, 5, 10 mg*l-1 Nano-silver particles, 0, 4, 6 mM Aminooxy acetic acid and 0, 200 and 400 mg*l-1 8-hydroxyquinoline sulphate (3 Essential oils: Thymus essential oil and Stevia essential oils (0, 0.1 and 0.2 mg*l-1. Data were subjected to analysis of variance based on the factorial experiment model in the layout completely randomized design. Mean comparison was performed using the Duncan’s multiple range test. Parameters of fresh weight, stem bending, capitulum diameter, carotenoid pigments of petal and vase-life longevity were evaluated during 12 days. The highest fresh weight was obtained when cut flowers were held in a solution containing pulse1 + 250 mg*l-1 BA. Among all treatments, 8-HQS treatment showed the best effects on preventing stem bending, increasing capitulum diameter and also on prolonging of vase-life, but nonetheless, the effects of pulse treatments and 8-HQS concentrations were insignificant. To conclude, 200 mg*l-1 8-HQS without pulse treatment has the potential to be used as a commercial preservative solution to improve the keeping quality and vase-life of this important cut flower.

  14. Sublethal imidacloprid effects on honey bee flower choices when foraging.

    Science.gov (United States)

    Karahan, Ahmed; Çakmak, Ibrahim; Hranitz, John M; Karaca, Ismail; Wells, Harrington

    2015-11-01

    Neonicotinoids, systemic neuro-active pesticides similar to nicotine, are widely used in agriculture and are being investigated for a role in honey bee colony losses. We examined one neonicotinoid pesticide, imidacloprid, for its effects on the foraging behavior of free-flying honey bees (Apis mellifera anatoliaca) visiting artificial blue and white flowers. Imidacloprid doses, ranging from 1/5 to 1/50 of the reported LD50, were fed to bees orally. The study consisted of three experimental parts performed sequentially without interruption. In Part 1, both flower colors contained a 4 μL 1 M sucrose solution reward. Part 2 offered bees 4 μL of 1.5 M sucrose solution in blue flowers and a 4 μL 0.5 M sucrose solution reward in white flowers. In Part 3 we reversed the sugar solution rewards, while keeping the flower color consistent. Each experiment began 30 min after administration of the pesticide. We recorded the percentage of experimental bees that returned to forage after treatment. We also recorded the visitation rate, number of flowers visited, and floral reward choices of the bees that foraged after treatment. The forager return rate declined linearly with increasing imidacloprid dose. The number of foraging trips by returning bees was also affected adversely. However, flower fidelity was not affected by imidacloprid dose. Foragers visited both blue and white flowers extensively in Part 1, and showed greater fidelity for the flower color offering the higher sugar solution reward in Parts 2 and 3. Although larger samples sizes are needed, our study suggests that imidacloprid may not affect the ability to select the higher nectar reward when rewards were reversed. We observed acute, mild effects on foraging by honey bees, so mild that storage of imidacloprid tainted-honey is very plausible and likely to be found in honey bee colonies.

  15. Anisotropic cell growth-regulated surface micropatterns in flower petals

    Directory of Open Access Journals (Sweden)

    Xiao Huang

    2017-05-01

    Full Text Available Flower petals have not only diverse macroscopic morphologies but are rich in microscopic surface patterns, which are crucial to their biological functions. Both experimental measurements and theoretical analysis are conducted to reveal the physical mechanisms underlying the formation of minute wrinkles on flower petals. Three representative flowers, daisy, kalanchoe blossfeldiana, and Eustoma grandiflorum, are investigated as examples. A surface wrinkling model, incorporating the measured mechanical properties and growth ratio, is used to elucidate the difference in their surface morphologies. The mismatch between the anisotropic epidermal cell growth and the isotropic secretion of surficial wax is found to dictate the surface patterns.

  16. Water relations and keeping-quality of cut Gerbera flowers

    OpenAIRE

    Meeteren, van, U.

    1980-01-01

    The aim of the present investigation is to study the internal water relations,of ageing Gerbera inflorescences and their consequence on keepingquality of cut inflorescences. As in all parts of this paper, the term "flower" will be used to describe an inflorescence with its supporting stem.A great problem during vase-life of cut Gerbera flowers is ',stem break", a sudden bending of the stem. As described in part 1, this phenomenon was caused by a water shortage in the flower. The water-stress ...

  17. Gene control of flowering time in higher plants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Flowering involves a transition process from vegetative growth to reproductive development, in which a series of routine changes take place in the shoot apical meristems from metabolic pathway to external phenotype. Expression of the genes related to flowering is the foundation for achieving the transition. Environmental factors (such as vernalization and photoperiod) and the growth status of cell itself induce the expression of the specific genes. A lot of achievements have been made recently in gene control for the determination of flowering time. The article reviews some new advances of such researches related to our work and the interesting field.

  18. Phytosynthesis of Cadmium Oxide Nanoparticles from Achillea wilhelmsii Flowers

    Directory of Open Access Journals (Sweden)

    Javad Karimi Andeani

    2013-01-01

    Full Text Available The study here deals with the plant synthesis of cadmium oxide nanoparticles using flowers extract of Achillea wilhelmsii as the reducing agent. The photosynthesis is carried out at room temperature in the laboratory ambience. The aqueous cadmium ions when exposed to flower extract were reduced and resulted in their nanoparticles. The synthesized nanoparticles were characterized using techniques such as scanning electron microscope (SEM, Fourier transform infrared spectroscopy (FTIR, and UV-visible absorption spectroscopy. Stable cadmium oxide nanoparticles were formed by treating aqueous solution of cadmium chloride (CdCl2 with the plant flower extracts as reducing agent.

  19. Reproducing under a warming climate: long winter flowering and extended flower longevity in the only Mediterranean and maritime Primula.

    Science.gov (United States)

    Aronne, G; Buonanno, M; De Micco, V

    2015-03-01

    Under the pressure of global warming, general expectations of species migration and evolution of adaptive traits should always be confirmed with species-specific studies. Within this framework, some species can be used as study systems to predict possible consequences of global warming also on other relatives. Unlike its mountain congeneric, Primula palinuri Petagn. has endured all the climatic fluctuations since the Pleistocene, while surviving on Mediterranean coastal cliffs. The aim of this work was to investigate the possible evolution of reproductive biological and ecological traits in P. palinuri adaptation to a warmer environment. Data showed that flowering starts in mid-winter; single flowers remain open for over a month, changing from pendulous to erect. The number of insects visiting flowers of P. palinuri increases during the flowering season, and pollination reduces flower longevity. Overall, the best pollen performances, in terms of viability and germinability, occur at winter temperatures, while pollinator activity prolongs flowering until spring. Moreover, extended longevity of single flowers optimises reproductive success. Both phenotypic plasticity and selective processes might have occurred in P. palinuri. However, we found that reproductive traits of the only Mediterranean Primula remain more associated with cold mountain habitats than warm coastal cliffs. Given the rapid trend of climate warming, migration and new adaptive processes in P. palinuri are unlikely. Response to past climate warming of P. palinuri provides useful indications for future scenarios in other Primula species.

  20. A large scale joint analysis of flowering time reveals independent temperate adaptations in maize

    Science.gov (United States)

    Modulating days to flowering is a key mechanism in plants for adapting to new environments, and variation in days to flowering drives population structure by limiting mating. To elucidate the genetic architecture of flowering across maize, a quantitative trait, we mapped flowering in five global pop...

  1. Natural variation in flowering time among populations of the annual crucifer Arabidopsis thaliana

    NARCIS (Netherlands)

    Hammad, I.; Van Tienderen, P.H.

    1997-01-01

    Genetic variation in flowering time was studied in four natural populations of Arabidopsis thaliana, using greenhouse experiments. Two populations from ruderal sites flowered early, two others from river dykes late. However, the late flowering plants flowered almost as early as the others after cold

  2. A nonpeptidyl growth hormone secretagogue.

    Science.gov (United States)

    Smith, R G; Cheng, K; Schoen, W R; Pong, S S; Hickey, G; Jacks, T; Butler, B; Chan, W W; Chaung, L Y; Judith, F

    1993-06-11

    A nonpeptidyl secretagogue for growth hormone of the structure 3-amino-3-methyl-N-(2,3,4,5-tetrahydro-2-oxo-1-([2'-(1H-tetrazol-5 -yl) (1,1'-biphenyl)-4-yl]methyl)-1H-1-benzazepin-3(R)-yl)-butanamid e (L-692,429) has been identified. L-692,429 synergizes with the natural growth hormone secretagogue growth hormone-releasing hormone and acts through an alternative signal transduction pathway. The mechanism of action of L-692,429 and studies with peptidyl and nonpeptidyl antagonists suggest that this molecule is a mimic of the growth hormone-releasing hexapeptide His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 (GHRP-6). L-692,429 is an example of a nonpeptidyl specific secretagogue for growth hormone.

  3. Reliable Global Navigation System using Flower Constellation

    Directory of Open Access Journals (Sweden)

    Daniele Mortari

    2013-03-01

    interest. Optimization of such constellations is a complex problem and the general-purpose constellation design methodology used today is largely limited to Walker-like constellations. As opposed to Walker Constellations [1], [2], which were looking for symmetries in inertial reference frame, Flower Constellations [11] were devised to obtain symmetric distributions of satellites on rotating reference frames (e.g., Earth, Jupiter, satellite orbit. Since the theory of Flower Constellations has evolved with time the next section is dedicated to the summary of the theory up to the current status. The FCs solution space has been recently expanded with the Lattice theory [13], [14], encompassing all possible symmetric solutions.

  4. A study of extraction of petal region on flower picture using HSV color information

    Science.gov (United States)

    Yanagihara, Yoshio; Nakayama, Ryo

    2014-01-01

    It is one of useful and interesting applications to discriminate the kind of the flower or recognize the name of the flower, as example of retrieving flower database. As its contour line of the petal region of flower is useful for such problems, it is important to extract the precise region of the petal of a flower picture. In this paper, the method which extracts petal regions on a flower picture using HSV color information is proposed, such to discriminate the kind of the flower. The experiments show that the proposed method can extract petal regions at the success rate of about 90%, which is thought to be satisfied. In detail, the success rates of one-colored flower, plural-colored flower, and white flower are about 98%, 85%, and 83%, respectively.

  5. Growth hormone and aging

    OpenAIRE

    Bartke, Andrzej; Brown-Borg, Holly; Kinney, Beth; Mattison, Julie; Wright, Chris; Hauck, Steven; Coschigano, Karen; Kopchick, John

    2000-01-01

    The potential usefulness of growth hormone (GH) as an anti-aging therapy is of considerable current interest. Secretion of GH normally declines during aging and administration of GH can reverse age-related changes in body composition. However, mutant dwarf mice with congenital GH deficiency and GH resistant GH-R-KO mice live much longer than their normal siblings, while a pathological elevation of GH levels reduces life expectancy in both mice and men. We propose that the actions of GH on gro...

  6. Analgesic activity of various extracts of Punica granatum (Linn flowers

    Directory of Open Access Journals (Sweden)

    Chakraborthy Guno

    2008-01-01

    Full Text Available The extracts of flowers of Punica granatum (Linn. (N.O. Family Punicaceae were investigated for analgesic activity in mice using hot plate method. The flowers of Punica granatum (Linn were collected from the local market of Mumbai, Maharashtra and were in a dried condition. The dried powdered flowers (500 gm were extracted in a soxhlet apparatus by using different solvents. Mice weighing 15-25 gm were taken for the experiment. The reaction time of animals in all the groups was noted at 30, 60 and 120 min after drug administration. All data were analyzed with Student-t test. The various extract of the flowers of Punica granatum (Linn showed significant analgesic activity at a dose of 50 mg/kg body weight. A maximum analgesic activity was found at 60 min, after drug administration, which was equivalent to the standard drug used as morphine sulphate.

  7. Antioxidant and cytotoxic activity of Acanthus ilicifolius flower

    Institute of Scientific and Technical Information of China (English)

    Muhamad Firdaus; Asep Awaludin Prihanto; Rahmi Nurdiani

    2013-01-01

    Objective: To investigate the antioxidant and cytotoxic activity of the flower of Acanthus ilicifolius (A. ilicifolius). Methods: Antioxidant activity was determined as antiradical efficiency with diphenyl picrylhydrazil (DPPH) method and cytotoxic assay was undertaken using brine shrimp lethal toxicity test. Results: A. ilicifolius flower contained terpenoid, phenolic compounds, and alkaloid. The methanol extract of A. ilicifolius flower showed the highest antiradical efficiency (AE=1.41í10-3) against DPPH radicals and the highest cytotoxicity (LC50=22 μg/mL) against brine shrimp nauplii. Conclusions: It is suggested that active compounds of A. ilicifolius flower solved in methanol play a role to inhibit free radical activity and kill Artemia salina nauplii. The substances can be considered as potential antioxidant and cytotoxic agents as well as imminent candidate for cancer therapy.

  8. Antioxidant and cytotoxic activity of Acanthus ilicifolius flower

    Institute of Scientific and Technical Information of China (English)

    Muhamad; Firdaus; Asep; Awaludin; Prihanto; Rahmi; Nurdiani

    2013-01-01

    Objective:To investigate the antioxidant and cytotoxic activity of the flower of Acanthus ilicifolius(A.ilicifolius).Methods:Antioxidant activity was determined as antiradical efficiency with diphenyl picrylhydrazil(DPPH)method and cytotoxic assay was undertaken using brine shrimp lethal toxicity test.Results:A.ilicifolius flower contained terpenoid,phenolic compounds,and alkaloid.The methanol extract of A.ilicifolius flower showed the highest antiradical efficiency(AE=1.41×10-3)against DPPH radicals and the highest cytotoxicity(LC50=22μg/mL)against brine shrimp nauplii.Conclusions:It is suggested that active compounds of A.ilicifolius flower solved in methanol play a role to inhibit free radical activity and kill Artemia salina nauplii.The substances can be considered as potential antioxidant and cytotoxic agents as well as imminent candidate for cancer therapy.

  9. Pollination in the Antarctic flowering plant Colobanthus quitensis (Kunth Bartl.

    Directory of Open Access Journals (Sweden)

    Irena Giełwanowska

    2012-12-01

    Full Text Available Colobanthus quitensis forms chasmogamic and cleistogamic flowers. Their structure signals the possibility of both cross-pollination and self-pollination. In favorable conditions (natural or laboratory, flowers open creating a possibility for cross-pollination. The occurrence of cleistogamy in the investigated species may be conditioned by abiotic factors: low temperature, high air humidity, and strong wind. In closed flowers, a part of pollen grains reaches the stigma surface, and the rest remains inside the microsporangium. Pollen grains germinate on the stigma surface or inside the microsporangium. Often, two or more pollen tubes grow from a single pollen grain. Closed flowers and the direct contact between the style stigma and anther prove the preference for autogamy. Autogamy ensures the reproductive success of the investigated plant in the exceptionally harsh Antarctic environment.

  10. Anthocyanin-dependent anoxygenic photosynthesis in coloured flower petals?

    Science.gov (United States)

    Lysenko, Vladimir; Varduny, Tatyana

    2013-11-01

    Chlorophylless flower petals are known to be composed of non-photosynthetic tissues. Here, we show that the light energy storage that can be photoacoustically measured in flower petals of Petunia hybrida is approximately 10-12%. We found that the supposed chlorophylless photosynthesis is an anoxygenic, anthocyanin-dependent process occurring in blue flower petals (ADAPFP), accompanied by non-respiratory light-dependent oxygen uptake and a 1.5-fold photoinduced increase in ATP levels. Using a simple, adhesive tape stripping technique, we have obtained a backside image of an intact flower petal epidermis, revealing sword-shaped ingrowths connecting the cell wall and vacuole, which is of interest for the further study of possible vacuole-related photosynthesis. Approaches to the interpretations of ADAPFP are discussed, and we conclude that these results are not impossible in terms of the known photochemistry of anthocyanins.

  11. Plant-herbivore synchrony and selection on plant flowering phenology.

    Science.gov (United States)

    Fogelström, Elsa; Olofsson, Martin; Posledovich, Diana; Wiklund, Christer; Dahlgren, Johan P; Ehrlén, Johan

    2017-03-01

    Temporal variation in natural selection has profound effects on the evolutionary trajectories of populations. One potential source of variation in selection is that differences in thermal reaction norms and temperature influence the relative phenology of interacting species. We manipulated the phenology of the butterfly herbivore Anthocharis cardamines relative to genetically identical populations of its host plant, Cardamine pratensis, and examined the effects on butterfly preferences and selection acting on the host plant. We found that butterflies preferred plants at an intermediate flowering stage, regardless of the timing of butterfly flight relative to flowering onset of the population. Consequently, the probability that plant genotypes differing in timing of flowering should experience a butterfly attack depended strongly on relative phenology. These results suggest that differences in spring temperature influence the direction of herbivore-mediated selection on flowering phenology, and that climatic conditions can influence natural selection also when phenotypic preferences remain constant.

  12. Time after time: flowering phenology and biotic interactions

    NARCIS (Netherlands)

    Elzinga, J.A.; Atlan, A.; Biere, A.; Gigord, L.; Weis, A.E.; Bernasconi, G.

    2007-01-01

    The role of biotic interactions in shaping plant flowering phenology has long been controversial; plastic responses to the abiotic environment, limited precision of biological clocks and inconsistency of selection pressures have generally been emphasized to explain phenological variation. However, p

  13. Hydroponic technology for lily flowers and bulbs production using ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-07-22

    Jul 22, 2015 ... Author(s) agree that this article remains permanently open access under the terms of the ... the utilization of the hydroponic technology to produce flower and ... chemical analysis of nutrient solutions, the highly modern.

  14. Let's Stop Teaching About Sex (of the Flowering Plants)

    Science.gov (United States)

    Davidson, John F.; Thelen, Leverne J

    1969-01-01

    Points out common misconceptions, especially the idea that pollination in flowering plants corresponds to fertilization in animals. Gives history of understanding of plant sexuality, then summarizes modern view. Suggests we teach accurately or not at all. (EB)

  15. Timing of Photoperiodic Flowering:Light Perception and Circadian Clock

    Institute of Scientific and Technical Information of China (English)

    Yun Zhou; Xiao-Dong Sun; Min Ni

    2007-01-01

    Flowering symbolizes the transition of a plant from vegetative phase to reproductive phase and is controlled by fairly complex and highly coordinated regulatory pathways. Over the last decade, genetic studies in Arabidopsis have aided the discovery of many signaling components involved in these pathways. In this review, we discuss how the timing of flowering is regulated by photoperiod and the involvement of light perception and the circadian clock in this process. The specific regulatory mechanisms on CONSTANS expression and CONSTANS stability by the circadian clock and photoreceptors are described in detail. In addition, the roles of CONSTANS, FLOWERING LOCUS T, and several other light signaling and circadiandependent components in photoperiodic flowering are also highlighted.

  16. Studies on In Vitro Flowering and Fruiting of Perilla frutescens

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tao

    2007-01-01

    Influences of PGR, sucrose, and ammonium nitrate on in vitro flowering and fruiting from cotyledon explants of P. frutescens were studied. The regenerated shoots at 2-4 cm from cotyledon explants on MS medium supplemented with 0.5 mg L-1 BA and 1.0 mg L-1 IAA were excised and transferred to MS medium containing 30 g L-1 sucrose, 8.25 g L-1 ammonium nitrate, and 1.0 mg L-1 BA. Following 40 d of culture, 86.2% of them flowered and set seeds. These seeds were germinable and developed into flowering plants in the fields. This study provides a simple system for rapid breeding of P. frutescens and studying the physiological mechanism of flowering of plants.

  17. Carolina Sandhills National Wildlife Refuge Flowering Plant List

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The following flowering plant list includes 79 plant species found on the refuge. Botanists have identified more than 750 species of plants on the refuge since it...

  18. Symmetric metamaterials based on flower-shaped structure

    Energy Technology Data Exchange (ETDEWEB)

    Tuong, P.V. [Department of Physics, Quantum Photonic Science Research Center and Research Institute for Nature Sciences, Hanyang University, Seoul 133-791 (Korea, Republic of); Institute of Material Sciences, Vietnam Academy of Science and Technology, Hanoi (Viet Nam); Park, J.W. [Department of Physics, Quantum Photonic Science Research Center and Research Institute for Nature Sciences, Hanyang University, Seoul 133-791 (Korea, Republic of); Rhee, J.Y. [Sungkyunkwan University, Suwon (Korea, Republic of); Kim, K.W. [Sunmoon University, Asan (Korea, Republic of); Cheong, H. [Sogang University, Seoul (Korea, Republic of); Jang, W.H. [Electromagnetic Wave Institute, Korea Radio Promotion Association, Seoul (Korea, Republic of); Lee, Y.P., E-mail: yplee@hanyang.ac.kr [Department of Physics, Quantum Photonic Science Research Center and Research Institute for Nature Sciences, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2013-08-15

    We proposed new models of metamaterials (MMs) based on a flower-shaped structure (FSS), whose “meta-atoms” consist of two flower-shaped metallic parts separated by a dielectric layer. Like the non-symmetric MMs based on cut-wire-pairs or electric ring resonators, the symmetrical FSS demonstrates the negative permeability at GHz frequencies. Employing the results, we designed a symmetric negative-refractive-index MM [a symmetric combined structure (SCS)], which is composed of FSSs and cross continuous wires. The MM properties of the FSS and the SCS are presented numerically and experimentally. - Highlights: • A new designed of sub-wavelength metamaterial, flower-shaped structure was proposed. • Flower-shaped meta-atom illustrated effective negative permeability. • Based on the meta-atom, negative refractive index was conventionally gained. • Negative refractive index was demonstrated with symmetric properties for electromagnetic wave. • Dimensional parameters were studied under normal electromagnetic wave.

  19. Baseline assessment of fish communities of the Flower Garden Banks

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The work developed baseline information on fish and benthic communities within the Flower Garden Banks National Marine Sanctuary (FGBNMS). Surveys employed diving,...

  20. Hummingbirds at artificial flowers made to resemble ornithophiles versus melittophiles

    Directory of Open Access Journals (Sweden)

    Wyndee A. Guzman

    2012-06-01

    Full Text Available Certain floral characteristics are associated with specific pollinators. Hummingbird-pollinated flowers are usually red, lack a landing platform, lack nectar guides, and contain a high amount of dilute sucrose-rich nectar. Here we test hypotheses concerning the reasons for these characters to the extent that they involve hummingbird responses. An array was set up of 16 artificial plants, each with five artificial flowers. (1 Flowers made to differ only in colour elicited a slight preference for red. (2 When colour was associated with nectar offerings, and birds generally learned to visit flowers that provided much more nectar but did not associatively learn differences as little as 2 µL. (3 Birds were offered 8 µL of 12% sucrose versus 2 µL of 48% hexose, and they did not prefer the dilute nectar; they showed no evidence of discerning sucrose from hexose; however, they preferred 48% over 12% sucrose when both were offered in the same quantity. (4 Birds preferred flowers that lacked landing platforms over those with landing platforms. (5 Birds were offered flowers with nectar guides, associated with differing nectar volumes, and they did not associate the higher nectar reward with either flower type. In summary, the feedback from hummingbirds reflects some of the differences between bird- and bee-adapted flowers, but nectar seemed less predictive than expected. Factors other than the behavioural proclivities of hummingbirds, such as adaptation to discourage bees, are discussed as additional causes for the differences between the syndromes. We also discuss significance testing for field experiments involving one unreplicated array.

  1. A major gene for time of flowering in chickpea.

    Science.gov (United States)

    Kumar, J; van Rheenen, H A

    2000-01-01

    A major gene for the number of days from sowing to appearance of the first flower (time of flowering) was identified in a cross between an extrashort duration chickpea (Cicer arietinum L.) variety, ICCV 2, and a medium duration variety, JG 62. The F2 population was advanced through the single-seed-descent method to develop random recombinant inbred lines (RILs). Time of flowering was recorded for the parents and 66 F(6) RILs from this cross that were grown in a Vertisol field in the post-rainy season of 1996-1997. Similarly the parents, F(1) and F(10) RILs were evaluated in 1997-1998. The F(1) flowered along with JG 62. The time of flowering for the two sets of RILs showed bimodal distributions with nearly equal peaks. One peak corresponded with ICCV 2 and the other with JG 62. This suggests that a single gene controls the difference for the time of flowering between ICCV 2 and JG 62 and the allele carried by the latter parent is dominant. To our knowledge no gene has been identified for the time of flowering in chickpea. Therefore the allele carried by JG 62 is designated as Efl-1 and that by ICCV 2 as efl-1. The proposed genotype for ICCV 2 is efl-1 efl-1 and for JG 62 is Efl-1 Efl-1. The genotype efl-1 efl-1 reduces the time of flowering at ICRISAT by nearly 3 weeks. The significance of this gene for breeding for early maturity and genome mapping has been discussed.

  2. Shielding Flowers Developing under Stress: Translating Theory to Field Application.

    Science.gov (United States)

    Chayut, Noam; Sobol, Shiri; Nave, Nahum; Samach, Alon

    2014-07-11

    Developing reproductive organs within a flower are sensitive to environmental stress. A higher incidence of environmental stress during this stage of a crop plants' developmental cycle will lead to major breaches in food security. Clearly, we need to understand this sensitivity and try and overcome it, by agricultural practices and/or the breeding of more tolerant cultivars. Although passion fruit vines initiate flowers all year round, flower primordia abort during warm summers. This restricts the season of fruit production in regions with warm summers. Previously, using controlled chambers, stages in flower development that are sensitive to heat were identified. Based on genetic analysis and physiological experiments in controlled environments, gibberellin activity appeared to be a possible point of horticultural intervention. Here, we aimed to shield flowers of a commercial cultivar from end of summer conditions, thus allowing fruit production in new seasons. We conducted experiments over three years in different settings, and our findings consistently show that a single application of an inhibitor of gibberellin biosynthesis to vines in mid-August can cause precocious flowering of ~2-4 weeks, leading to earlier fruit production of ~1 month. In this case, knowledge obtained on phenology, environmental constraints and genetic variation, allowed us to reach a practical solution.

  3. Flower bouquet variation in four species of Crocus ser. Verni.

    Science.gov (United States)

    Carta, Angelino; Flamini, Guido; Cioni, Pier Luigi; Pistelli, Luisa; Peruzzi, Lorenzo

    2015-01-01

    Flowering plants employ a wide variety of signals, including scent, to attract pollinators. The aim of this work was to examine whether flower volatiles in four closely related Crocus species are linked to species divergence and to the current knowledge on their pollination syndromes. Fragrances of freshly opened flowers in Crocus etruscus, C. ilvensis, C. neglectus, and C. vernus, all belonging to ser. Verni, were analyzed using GC/MS. Results coincide with present knowledge about systematic relationships among taxa. The four species fall into two main fragrance types, based on similarities of their volatile compounds. In C. etruscus, C. ilvensis, and C. neglectus, oxygenated monoterpenes (lilac aldehyde B and A) are most abundant, while C. vernus has a fragrance rich in monoterpene hydrocarbons (α-pinene and limonene). Our results point towards outcrossing mating strategies for C. etruscus, C. ilvensis, and C. neglectus, whose volatile compounds are known as pollinator attractants. This is in line with their flower architecture, showing a style of variable height, often overtopping stamens. On the other hand, a self-pollination strategy was repeatedly suggested in the literature for C. vernus, marked by flowers with the style deeply inserted in the stamens and also by a completely different flower bouquet.

  4. Shielding Flowers Developing under Stress: Translating Theory to Field Application

    Directory of Open Access Journals (Sweden)

    Noam Chayut

    2014-07-01

    Full Text Available Developing reproductive organs within a flower are sensitive to environmental stress. A higher incidence of environmental stress during this stage of a crop plants’ developmental cycle will lead to major breaches in food security. Clearly, we need to understand this sensitivity and try and overcome it, by agricultural practices and/or the breeding of more tolerant cultivars. Although passion fruit vines initiate flowers all year round, flower primordia abort during warm summers. This restricts the season of fruit production in regions with warm summers. Previously, using controlled chambers, stages in flower development that are sensitive to heat were identified. Based on genetic analysis and physiological experiments in controlled environments, gibberellin activity appeared to be a possible point of horticultural intervention. Here, we aimed to shield flowers of a commercial cultivar from end of summer conditions, thus allowing fruit production in new seasons. We conducted experiments over three years in different settings, and our findings consistently show that a single application of an inhibitor of gibberellin biosynthesis to vines in mid-August can cause precocious flowering of ~2–4 weeks, leading to earlier fruit production of ~1 month. In this case, knowledge obtained on phenology, environmental constraints and genetic variation, allowed us to reach a practical solution.

  5. DELLA proteins interact with FLC to repress flowering transition

    Institute of Scientific and Technical Information of China (English)

    Hongwei Guo

    2016-01-01

    Flowering is a highly orchestrated and extremely critical process in a plant’s life cycle. Previous study has demonstrated that SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1) and FLOWERING LOCUS T (FT) integrate the gibberellic acid (GA) signaling pathway and vernalization pathway in regulating flowering time, but detailed molecular mechanisms remain largely unclear. In GA signaling pathway, DELLA proteins are a group of master transcriptional regulators, while in vernalization pathway FLOWERING LOCUS C (FLC) is a core transcriptional repressor that down-regulates the expression of SOC1 and FT. Here, we report that DELLA proteins interact with FLC in vitro and in vivo, and the LHRI domains of DELLAs and the C-terminus of MADS domain of FLC are required for these interactions. Phenotypic and gene expression analysis showed that mutation of FLC reduces while over-expression of FLC enhances the GA response in the flowering process. Further, DELLA-FLC interactions promote the repression ability of FLC on its target genes. In summary, these findings report that the interaction between MADS box transcription factor FLC and GRAS domain regulator DELLAs may integrate various signaling inputs in flowering time control, and shed new light on the regulatory mechanism both for FLC and DELLAs in regulating gene expression.

  6. Phenolic antioxidants from Rosa soulieana flowers.

    Science.gov (United States)

    Yang, Chunyan; Li, Fu; Zhang, Xiaolong; Wang, Lun; Zhou, Zhiqiong; Wang, Mingkui

    2013-01-01

    Rosa soulieana has been widely used in traditional medicine to treat cardiovascular disorders. In this study, antioxidant activity-guided fractionation and purification of the methanol extract from the flowers of R. soulieana has led to the isolation of nine phenolic antioxidants, which were identified as catechin (1), tiliroside (2), astragalin (3), isoquercitrin (4), nicotiflorin (5), eugenol 4-O-β-d-(6'-O-galloyl) glucoside (6), michehedyosides D (7), citrusin C (8) and strictinin (9), respectively. Among them, compounds 5-9 were reported from the genus Rosa for the first time. All the compounds were also assayed by in vitro ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt] radical cation scavenging activity. Among these bioactive isolates (1-9), compounds 1, 6, 7 and 9 exhibited strong scavenging activity in ABTS (SC50 = 10.17, 7.38, 8.60, 4.72 μmol/L, respectively) compared with the positive control l-ascorbic acid (SC50 = 15.97 μmol/L).

  7. Changes of Endogenous Hormone Contents in Fruit, Seeds and Their Effects on the Fruit Development of Rosa roxburghii

    Institute of Scientific and Technical Information of China (English)

    FAN Wei-guo; AN Hua-ming; LIU Guo-qin; HE Song-tao; LIU Jin-ping

    2003-01-01

    The fruit of cultivar Guinong5 (Rosa roxburghii Tratt. ) was used to investigate the regularity of its growth and development, and the changes of endogenous hormone contents during the period of the growth and development. The result showed that contents of GA1+3, IAA and ZRs in the flower receptacle of young fruit were high and then decreased, contents of GA1+3 and IAA in seeds increased with its development until maturity. The contents of ZRs and ABA in the flower receptacle of young fruits and seeds were high, and then had a tendency of descent with the development of fruits. The contents of GA1+3, IAA, ZRs and ABA in flower receptacle of young fruit with normal fertilization were much higher than those of in non-fertilization fruits. In the flower receptacle of malformed fruits, the contents of GA1+3, IAA and ZRs in normally developing flower receptacle were significantly higher than those in malformed fruits. The growth and development of fruits depended largely on the seeds, development because the seeds in the fruits with non-fertilization failed to be formed or even formed but irreproducible, which would lead to the decrease of GA1+3, IAA contents and the abnormal development of fruits. Therefore the fruits deformed and dropped inevitably.

  8. [Hormone replacement therapy--growth hormone, melatonin, DHEA and sex hormones].

    Science.gov (United States)

    Fukai, Shiho; Akishita, Masahiro

    2009-07-01

    The ability to maintain active and independent living as long as possible is crucial for the healthy longevity. Hormones responsible for some of the manifestations associated with aging are growth hormone, insulin-like growth factor-1 (IGF-1), melatonin, dehydroepiandrosterone (DHEA), sex hormones and thyroid hormones. These hormonal changes are associated with changes in body composition, visceral obesity, muscle weakness, osteoporosis, urinary incontinence, loss of cognitive functioning, reduction in well being, depression, as well as sexual dysfunction. With the prolongation of life expectancy, both men and women today live the latter third life with endocrine deficiencies. Hormone replacement therapy may alleviate the debilitating conditions of secondary partial endocrine deficiencies by preventing or delaying some aspects of aging.

  9. Evolutionary, genetic, environmental and hormonal-induced plasticity in the fate of organs arising from axillary meristems in Passiflora spp.

    Science.gov (United States)

    Cutri, Lucas; Nave, Nahum; Ami, Michal Ben; Chayut, Noam; Samach, Alon; Dornelas, Marcelo Carnier

    2013-01-01

    Tendrils can be found in different plant species. In legumes such as pea, tendrils are modified leaves produced by the vegetative meristem but in the grape vine, a same meristem is used to either form a tendril or an inflorescence. Passiflora species originated in ecosystems in which there is dense vegetation and competition for light. Thus climbing on other plants in order to reach regions with higher light using tendrils is an adaptive advantage. In Passiflora species, after a juvenile phase, every leaf has a subtending vegetative meristem, and a separate meristem that forms both flowers and a tendril. Thus, flowers are formed once a tendril is formed yet whether or not this flower will reach bloom depends on the environment. For example, in Passiflora edulis flowers do not develop under shaded conditions, so that tendrils are needed to bring the plant to positions were flowers can develop. This separate meristem generally forms a single tendril in different Passiflora species yet the number and position of flowers formed from the same meristem diverges among species. Here we display the variation among species as well as variation within a single species, P. edulis. We also show that the number of flowers within a specific genotype can be modulated by applying Cytokinins. Finally, this separate meristem is capable of transforming into a leaf-producing meristem under specific environmental conditions. Thus, behind what appears to be a species-specific rigid program regarding the fate of this meristem, our study helps to reveal a plasticity normally restrained by genetic, hormonal and environmental constraints.

  10. Flowering and pollen value of selected species of umbelliferous family - Umbelliferae Juss. (Apiaceae Lindl.) in Lublin region. Part 1. Biology and abundance of flowering

    OpenAIRE

    Anna Wróblewska

    2013-01-01

    Investigations of the biology of flowering and pollen value of seven species of Umbelliferae family were carried out in natural seats of Lublin region in 1978-1980. Aegopodium podagraria L.,Angelica silvestris L., Anthriscus silvestris L. (Hoffm.), Chaerophyllum aromaticum L., Eryngium planum L., Herac1eum sibiricum L., Pastinaca sativa L. were examined. This paper shows results of studies of the biology of flowering and abundance of flowering. The examined species started their flowering in ...

  11. Estimation of Moisture Content & Metal Ions in White Flowers of Bougainvillea spectabilis and Purple Flowers of Bougainvillea glabra in Pakistan

    OpenAIRE

    *S. A. Rashid; F. S. Rehmani; Arman, M; Ibrahim, M; Shafique, S.

    2011-01-01

    Bougainvillea consists of 18 shrubby species, growing in different parts of Pakistan and is being used as Anti-ulcer, Anti-diarrheal, Anti-microbial, Anti- diabetic, Amylase Inhibition and as for low blood pressure but none of the studies on Bougainvillea focused on the estimation of metal ion concentration. The focus of the present study was to estimation of moisture content and comparative analysis of trace metal ions in white flowers of Bougainvillea spectabilis Willd and Purple flowers of...

  12. Cloning and Analysis of a Florigen -like Gene in Gossypium barbadense L%海岛棉一个成花素类似基因的克隆和生物信息学分析

    Institute of Scientific and Technical Information of China (English)

    东锐; 张坤; 顾超; 郑银英; 崔百明; 黄先忠

    2011-01-01

    [Objective] To clone a FT -like homolog in Gossypium barbadense L.. [Method] A FT-like homolog was isolated from Gossypium barbadense L. Cultivar through RT - PCR techniques, which was designated as GbFTL1. The character of GbFTLl protein was analyzed by a series of bioinformatics software. [Result] A FT - like homolog named GbFTLl was isolated from Gossypium barbadense L. Cultivar of Xinhai 14. The open reading frame is 525 bp and encoded a putative protein of 174 amino acids which contains two critical residues and conserved motif, both of which were identified as diagnostics of true FT. Similarity comparison shows that the amino acid sequence of GbFTLl shares 79. 3% , 99. 4% identity with AtFT and GhFTL1, respectfully. GhFTL1 is Ser(S) in thirty - seventh amino acids, but GbFTLl is Asn(N). Phylogenetic analysis at the amino acid level confirmed that the isolated sequence is FT - like. [ Conclusion] GbFTLl may be one of the candidate gene of promoting flowering in Gossypium barbadense L.%[目的]海岛棉成花素类似基因的克隆及生物信息学分析.[方法]利用RT - PCR技术,从海岛棉中克隆成花素FLOWERING LOCUST(FT)的同源基因,并进行生物信息学分析.[结果]从新海14号花后15 d纤维中,克隆到一个棉花成花素类似基因FLOWERING LOCUS T- LIKE1,命名为GbFTL1.该基因的开放阅读框为525 bp,编码174个氨基酸.蛋白比对表明bFTL1和AtFT的相似性为79.3%,和陆地棉GhFTL1的相似性为99.4%,GbFTL1第37位氨基酸为Asn(N),而GhFTL1第37位氨基酸为Ser(S).GbFTL1含有FT蛋白亚家族两个关键的氨基酸残基及14个保守氨基酸,系统进化树分析表明GbFTL1属于FT亚家族成员.[结论]GbFTL1基因可能为海岛棉中促进开花的基因之一.

  13. Flowering biology of three taxa of the genus Scilla L. (Hyacinthaceae and flower visitation by pollinating insects

    Directory of Open Access Journals (Sweden)

    Beata Żuraw

    2012-12-01

    Full Text Available Squill of the family Hyacinthaceae is a small bulb perennial. The present study on flowering and pollination of Scilla sibirica Andr., S. sibirica 'Alba', and S. bifolia L. was conducted in the years 1995, 1997, and 1999 in the Botanical Garden of the Maria Curie-Skłodowska University in Lublin. The plants flowered from the end of March until the middle of May. The duration of flowering of individual taxa was similar and it averaged 20 days (Scilla sibirica, 21 days (S. sibirica 'Alba', and 23 days (S. bifolia. The opening of flower buds always started around 9.00 am and lasted, depending on the taxon, until 3.00 pm (Scilla sibirica 'Alba', 4.00 pm (S. bifolia, and 5.00 pm (S. sibirica. The flowers were visited by bees (Apoidea, primarily the honey bee (Apis mellifera L., bumblebee (Bombus L., and solitary bees. Numerous honey bee foragers were observed; they bit through the anther walls and even attempted to open still closed flower buds in order to reach the pollen.

  14. Flower diversity and bee reproduction in an arid ecosystem

    Directory of Open Access Journals (Sweden)

    Jimena Dorado

    2016-07-01

    Full Text Available Background: Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occupy the phenological space more broadly, increasing floral availability for pollinators throughout the season. In addition, this potential effect of flower diversity on bee reproduction could be stronger for generalist pollinators because they can use a broader floral spectrum. Based on above arguments we predicted that pollinator reproduction would be positively correlated to flower diversity, and to temporal stability in flower production, and that this relationship would be stronger for the most generalized pollinator species. Materials and Methods: Using structural equation models, we evaluated the effect of these variables and other ecological factors on three estimates of bee reproduction (average number of brood cells per nest per site, total number of brood cells per site, and total number of nests per site, and whether such effects were modulated by bee generalization on floral resources. Results: Contrary to our expectations, flower diversity had no effect on bee reproduction, stability in flower production had a weakly negative effect on one of the bee reproductive variables, and the strength of the fitness-diversity relationship was unrelated to bee generalization. In contrast, elevation had a negative effect on bee reproduction, despite the narrow elevation range encompassed by our sites. Discussion: Flower diversity did not affect the reproduction of the solitary bees studied here. This result could stem from the context dependence of the

  15. Short-term effects of burn season on flowering phenology of savanna plants

    Science.gov (United States)

    Pavlovic, N.B.; Leicht-Young, S. A.; Grundel, R.

    2011-01-01

    We examined the effect of season of burn on flowering phenology of groundlayer species, in the year following burns, in a mesic-sand Midwestern oak savanna. Burn treatments were fall, early-season, growing-season, late-season, and 1 or 5 years after a prior early-season wildfire. For these treatments, we compared the number of flowering stems and of flowers for species overall, for the 20 most prolifically flowering species, as well as for species grouped by flowering phenoperiods, and by growth form. Growing-season burn had a significant negative effect on number of flowering stems and total number of flowers. This effect occurred when either the burn occurred during the flowering season or during the season prior to the flowering phenoperiod. Tradescantia ohiensis showed expedited flowering and Phlox pilosa showed delayed flowering in response to early-season burning. Flowering of early shrubs was reduced by the previous fall and early-spring fires, while flowering of mid-season blooming shrubs was reduced by the early- and growing-season burns. Vaccinium and Gaylussacia, early-flowering shrubs, produced fewer flowers 1 year after than 5 years after an early-season burn. Arabis lyrata showed reduced flowering from the early-season burn. We also found four instances where the early-spring burn effect on flowering was more severe than the fall burn effect, suggesting that many frequent early-season burns may be deleterious to flowering and reproduction of some species. Burns occurring too frequently in the same season could negatively affect future flowering and reproduction of these plant species.

  16. Sex Hormones and Ischemic Stroke

    DEFF Research Database (Denmark)

    Holmegard, Haya N; Nordestgaard, Børge G; Jensen, Gorm B

    2016-01-01

    CONTEXT AND OBJECTIVE: Whether endogenous sex hormones are associated with ischemic stroke (IS) is unclear. We tested the hypothesis that extreme concentrations of endogenous sex hormones are associated with risk of IS in the general population. DESIGN, SETTING, AND PARTICIPANTS: Adult men (n...

  17. Thyroid hormone and the heart.

    Science.gov (United States)

    Moolman, J A

    2002-01-01

    Thyroid hormone has important cardiovascular effects, and abnormalities of its production cause cardiovascular morbidity. The role of both excessive and insufficient thyroid hormone production in the pathogenesis of clinical cardiac diseases can be deduced from thyroid hormone-induced molecular changes. Thyroid hormone regulates the expression of myocardial genes regulating the handling of calcium, which affects both systolic and diastolic myocardial function. Thyroid hormone also has indirect and direct effects on peripheral vascular smooth muscle tone, and alters the coupling of the left ventricle and arterial system. Excessive production of thyroid hormone results in an increased cardiac output as well as increased cardiac work efficiency, but reduced cardiac reserve. Amiodarone therapy for cardiac rhythm can cause both hyper- and hypothyroidism. Amiodarone-induced thyrotoxicosis (AIT) can be due to either excessive thyroid hormone production (type I AIT) or thyroid hormone release due to an inflammatory condition (type II AIT). Classification of AIT is helpful in guiding therapy. Amiodarone causes changes in the thyroid function tests of euthyroid patients on therapy--it inhibits the conversion of T(4) and T(3), which results in decreased T(3) and slightly increased T(4) serum levels in euthyroid patients. Baseline thyroid functions should therefore be determined before starting amiodarone therapy, and at 6-monthly intervals thereafter.

  18. Hormonal Programming Across the Lifespan

    Science.gov (United States)

    Tobet, Stuart A; Lara, Hernan E; Lucion, Aldo B; Wilson, Melinda E; Recabarren, Sergio E; Paredes, Alfonso H

    2013-01-01

    Hormones influence countless biological processes across the lifespan, and during developmental sensitive periods hormones have the potential to cause permanent tissue-specific alterations in anatomy and physiology. There are numerous critical periods in development wherein different targets are affected. This review outlines the proceedings of the Hormonal Programming in Development session at the US-South American Workshop in Neuroendocrinology in August 2011. Here we discuss how gonadal hormones impact various biological processes within the brain and gonads during early development and describe the changes that take place in the aging female ovary. At the cellular level, hormonal targets in the brain include neurons, glia, or vasculature. On a genomic/epigenomic level, transcription factor signaling and epigenetic changes alter the expression of hormone receptor genes across development and following ischemic brain insult. In addition, organizational hormone exposure alters epigenetic processes in specific brain nuclei and may be a mediator of sexual differentiation of the neonatal brain. During development of the ovary, exposure to excess gonadal hormones leads to polycystic ovarian syndrome (PCOS). Exposure to excess androgens during fetal development also has a profound effect on the development of the male reproductive system. In addition, increased sympathetic nerve activity and stress during early life have been linked to PCOS symptomology in adulthood. Finally, we describe how age-related decreases in fertility are linked to high levels of nerve growth factor (NGF), which enhances sympathetic nerve activity and alters ovarian function. PMID:22700441

  19. Hormones and β-Agonists

    NARCIS (Netherlands)

    Ginkel, van L.A.; Bovee, T.F.H.; Blokland, M.H.; Sterk, S.S.; Smits, N.G.E.; Pleadin, Jelka; Vulić, Ana

    2016-01-01

    This chapter provides some updated information on contemporary methods for hormone and β-agonist analyses. It deals with the classical approaches for the effective detection and identification of exogenous hormones. The chapter examines specific problems related to control strategies for natural

  20. Hormone therapy for transgender patients

    Science.gov (United States)

    2016-01-01

    Many transgender men and women seek hormone therapy as part of the transition process. Exogenous testosterone is used in transgender men to induce virilization and suppress feminizing characteristics. In transgender women, exogenous estrogen is used to help feminize patients, and anti-androgens are used as adjuncts to help suppress masculinizing features. Guidelines exist to help providers choose appropriate candidates for hormone therapy, and act as a framework for choosing treatment regimens and managing surveillance in these patients. Cross-sex hormone therapy has been shown to have positive physical and psychological effects on the transitioning individual and is considered a mainstay treatment for many patients. Bone and cardiovascular health are important considerations in transgender patients on long-term hormones, and care should be taken to monitor certain metabolic indices while patients are on cross-sex hormone therapy. PMID:28078219