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Structure of inflorescences and flowers and flowering behaviour are reported for the woody liana Anchietea pyrifolia (Violaceae) from Brazil. The specimen studied is grown for some decades now in the greenhouses of Halle Botanical...
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Structure of inflorescences and flowers and flowering behaviour are reported for the woody liana Anchietea pyrifolia (Violaceae) from Brazil. The specimen studied is grown for some decades now in the greenhouses of Halle Botanical Garden and turned out unisexually male, which adds a further example of dioecism to the family Violaceae, in which this type of sex distribution is rarely encountered. The flowers are exceptional also for the strongly asymmetric anterior petal, which represents a rare case of a species with enantiomorphic flowers pollinated by Lepidoptera. They have a fully developed gynoecium with a complicated architecture comparable to the pistil of bisexual Violaceae flowers, though without ovules. The style head is capable to release viscose liquid on tactile stimulation or pressure, which is known to act as pollen-gathering mechanism in bisexual Violaceae species with usually dry pollen and buzz-pollination. This function has switched in male. A pyrifolia to a mechanism for efficient pollen release mediated by insect pollinators from its short-lived flowers.
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The software FlowerMorphology is designed for automatic morphometry of actinomorphic flowers. The novel complex parameters of flowers calculated by FlowerMorphology allowed us to quantitatively characterize a polyploid series of tobacco.
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The diversity of angiosperm flowers is astounding. The conventional explanation for this diversity is that it represents the great variety of ways in which flowers have adapted to attract an even greater diversity of animal pollin...
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The diversity of angiosperm flowers is astounding. The conventional explanation for this diversity is that it represents the great variety of ways in which flowers have adapted to attract an even greater diversity of animal pollinators. Many animal behaviourists are therefore interested in how changes in floral morphology affect pollinator behaviour. The establishment of well-characterised model plant species has greatly furthered our understanding of how floral morphology is generated and varied. Many of these model species are pollinated by animals and attract their pollinators through the production of colour, shape, scent, size and rewards. An understanding of the developmental plasticity of floral morphology, and the constraints upon it, should inform research into animal responses to flowers. The use of genetically characterised model species, and the isogenic and near-isogenic lines available in them, will allow dissection of the different components of floral attraction and reward in natural systems.
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The foraging behavior of bees is a complex phenomenon that depends on numerous physical features of flowers. Of particular importance are accessibility of floral rewards, floral proportions, symmetry and orientation. The flowers o...
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The foraging behavior of bees is a complex phenomenon that depends on numerous physical features of flowers. Of particular importance are accessibility of floral rewards, floral proportions, symmetry and orientation. The flowers of Roepera are characterized by the presence of staminal scales (SS), which play an important role in nectar protection. We studied two species of Roepera with different symmetry and flower orientation, which are mainly visited by honeybees (Apis mellifera). We aimed to show how the foraging behavior of honey bees is affected by the function of SS, floral symmetry and orientation. The foraging behavior was documented by video photography. Handling time, access to nectar, percentage of pollen/nectar foraging, percentage of pollen contact and pollen deposition site on the honey bee's body were assessed. The morphometric features of the honey bees and flowers were analyzed. We found that the SS restricted pollinator access to nectar. Our results indicated consistency of visitation patterns in zygomorphic, laterally oriented flowers of R. fuscata versus random patterns in actinomorphic, diversely oriented flowers of R. leptopetala. The relative proportions of SS and proboscis length appear to be crucial for the success of pollinators. The directionality of the honey bees' movement, together with the different positioning of reproductive organs, plays an important role in the accuracy of pollen transfer and pollination efficiency.
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The foraging behavior of bees is a complex phenomenon that depends on numerous physical features of flowers. Of particular importance are accessibility of floral rewards, floral proportions, sy
The foraging behavior of bees is a complex phenomenon that depends on numerous physical features of flowers. Of particular importance are accessibility of floral rewards, floral proportions, symmetry and orientation. The flowers of
Roepera
are characterized by the presence of staminal scales (SS), which play an important role in nectar protection. We studied two species of
Roepera
with different symmetry and flower orientation, which are mainly visited by honeybees (
Apis mellifera
). We aimed to show how the foraging behavior of honey bees is affected by the function of SS, floral symmetry and orientation. The foraging behavior was documented by video photography. Handling time, access to nectar, percentage of pollen/nectar foraging, percentage of pollen contact and pollen deposition site on the honey bee's body were assessed. The morphometric features of the honey bees and flowers were analyzed. We found that the SS restricted pollinator access to nectar. Our results indicated consistency of visitation patterns in zygomorphic, laterally oriented flowers of
R. fuscata
versus random patterns in actinomorphic, diversely oriented flowers of
R. leptopetala
. The relative proportions of SS and proboscis length appear to be crucial for the success of pollinators. The directionality of the honey bees' movement, together with the different positioning of reproductive organs, plays an important role in the accuracy of pollen transfer and pollination efficiency.
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TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factors (TFs) are plant-specific transcriptional regulators exerting multiple functions in plant growth and development. Ever since one of the founding mem...
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TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factors (TFs) are plant-specific transcriptional regulators exerting multiple functions in plant growth and development. Ever since one of the founding members of the family was described, encoded by the CYCLOIDEA (CYC) gene from Antirrhinum majus and involved in the regulation of floral symmetry, the role of these TFs in reproductive development was established. Subsequent studies indicated that members of the CYC clade of TCP TFs were important for the evolutionary diversification of flower form in a multitude of species. In addition, more detailed studies of the function of TCPs from other clades revealed roles in different processes related to plant reproductive development, such as the regulation of flowering time, the growth of the inflorescence stem, and the correct growth and development of flower organs. In this review, we summarize the different roles of members of the TCP family during plant reproductive development as well as the molecular networks involved in their action.
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Flower bearing branching systems are of major importance for plant reproduction, and exhibit significant variation between and within lineages. A key goal in evolutionary biology is to discover and characterize changes in the gene...
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Flower bearing branching systems are of major importance for plant reproduction, and exhibit significant variation between and within lineages. A key goal in evolutionary biology is to discover and characterize changes in the genetic programming of development that drive the modification and diversification of morphology. Here we present a synopsis of reproductive architecture in Papaveraceae s.L, a lineage in which the evolution of inflorescence determinacy, flower structure and symmetry, and effloration sequence produced unique reproductive syndromes. We discuss the potential of this group to study key issues on the evolution of reproductive structures, and refer to candidate gene families, choice of landmark species, and available tools for developmental genetic investigations.
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The high variability observed in floral traits has been interpreted as resulting from the adaptation of plants to pollinators, as the latter present innate preferences for specific floral traits and impose selection over them. How...
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The high variability observed in floral traits has been interpreted as resulting from the adaptation of plants to pollinators, as the latter present innate preferences for specific floral traits and impose selection over them. However, some pollinators such as bees can learn to associate floral signals with rewards, thus increasing floral constancy on more rewarding flowers. The integration of all these rewards and cues is markedly important at community level, where co-flowering species compete for pollinators.
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We report four examples of morphological variation in the species of Cephalanthera (Orchidaceae) in Japan. We recognized a new peloric form, C. subaphylla Miyabe & Kudo f. conformis Hiros. Hayak. The new form has a tepal-like lip morphology. We also report variegation mutants of C. erecta (Thunb.) Blume var. erecta, which are albino-like in appearance. The above-ground parts of the mutants were withered at the immature seed stage during the end of June. We also observed variegated individuals of C. falcata (Thunb.) Blume f. falcata and C. falcata f. albescens S. Kobay. Finally, we discovered individuals of C. falcata f.falcata with a malformed flower at the top of an inflorescence with normal flowers in other parts of the same inflorescence from twolocalities....
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We report four examples of morphological variation in the species of Cephalanthera (Orchidaceae) in Japan. We recognized a new peloric form, C. subaphylla Miyabe & Kudo f. conformis Hiros. Hayak. The new form has a tepal-like lip morphology. We also report variegation mutants of C. erecta (Thunb.) Blume var. erecta, which are albino-like in appearance. The above-ground parts of the mutants were withered at the immature seed stage during the end of June. We also observed variegated individuals of C. falcata (Thunb.) Blume f. falcata and C. falcata f. albescens S. Kobay. Finally, we discovered individuals of C. falcata f.falcata with a malformed flower at the top of an inflorescence with normal flowers in other parts of the same inflorescence from twolocalities.
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Flowers constitute the iconic structure of the angiosperms, which represent 90% of the extant land plant species diversity. They are extremely diverse in size, colour and form. As a reproductive unit, a flower groups sterile organ...
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Flowers constitute the iconic structure of the angiosperms, which represent 90% of the extant land plant species diversity. They are extremely diverse in size, colour and form. As a reproductive unit, a flower groups sterile organs surrounding fertile organs on a short axis, following an almost invariable arrangement (see Nadot and Dodinet 2016): carpels enclosing ovules at the centre, surrounded by stamens enclosing pollen grains, then the sterile organs (perianth), often differentiated into external sepals forming the calyx, and internal petals forming the corolla. When the sterile organs are differentiated, the calyx usually protects the other organs during development, while the corolla plays a role in pollinator attraction.
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