Structure of floral nectaries and comparison of reproductive and vestigial organs in the staminate and pistillate flowers of dioecious Silene latifolia (Caryophyllaceae)

Silene latifolia Poiret of Eurasia has established in North America, prompting this structural study of its mature unisexual buds and flowers. Floral nectaries, anther and stigma changes, and vestigial reproductive structures were studied using light and scanning electron microscopy. In staminate flowers, anthers dehisced before anthesis and >90% of their pollen was liberated within 36 h. Accumulated in the tubular calyx, nectar descended an anthophore from the stomatal-bearing nectary at the stamen bases. Nectary tissue surrounded the pistillode, a central filamentous organ lacking ovules but tipped by hairs resembling stigmatic papillae. In pistillate flowers, nectar flowed into an inflated calyx. The annular nectary had 10 regularly spaced, stomatal-lined craters and was continuous with the adaxial surfaces of the infertile antisepalous and epipetalous staminodes. Key elements of entomophilous pollination leading to successful sexual reproduction of this invasive species include secondary nectar presentation from disparate floral nectaries that, for pistillate flowers, also incorporate the staminodes; rapid pollen release from anthers; and elongation of papillae by tip growth that enhances each stigma’s receptive surface. Context is also provided for future studies of floral nectary development in this model dioecious species.

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Micromorphology of Sorbus intermedia Pers. nectary surface in different phases of blooming

Acta Agrobotanica ◽

10.5586/aa.2006.005 ◽

2012 ◽

Vol 59 (1) ◽

pp. 49-59

Author(s):

Elżbieta Weryszko-Chmielewska ◽

Agata Konarska

Keyword(s):

Flower Development ◽

Cell Walls ◽

Guard Cells ◽

Outer Cell ◽

Final Phase ◽

Floral Nectary ◽

Pollen Release ◽

Epidermis Cell ◽

Outer Cell Wall ◽

Scanning Electron

The structure of floral nectary surface of Sorbus intermedia in different phases of flower development was examined using scanning electron microscopy. Nectaries in S. intermedia flowers represent a receptacle type. The sculpture of cuticule on nectary epidermis and overlaying cells was described. The differences in the size of striaes on the outer cell wall of epidermis during the flower development were stated. Nectarostomata were situated in small hollows. In the buds, they were closed and not fully developed. During pollen release phase, the outer ledges of the guard cells were better developed than at the beginning of blooming. Depressions on nectary epidermis cell walls were observed in the final phase of blooming.

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Micromorphology of the epidermis of the floral nectary of Rhododendron japonicum (A. Gray) J. V. Suringar ex E.H. Wilson.

Acta Agrobotanica ◽

10.5586/aa.2007.005 ◽

2012 ◽

Vol 60 (1) ◽

pp. 45-53 ◽

Cited By ~ 3

Author(s):

Elżbieta Weryszko-Chmielewska ◽

Mirosława Chwil

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Growth Stages ◽

Mosaic Pattern ◽

Floral Nectary ◽

Half Height ◽

Floral Nectaries ◽

Small Clusters ◽

Different Growth Stages ◽

Scanning Electron

The conducted study related to the structure of the floral nectaries of Rhododendron japonicum (A. Gray) J. V. Suringar ex E. H. Wilson. The structure of the secretory epidermis of the nectaries was analysed by using scanning electron microscopy (SEM). Rhododendron japonicum develops the superior pistil with a 5-loculed ovary equipped in five ribs. The nectary gland is located in the lower part of the ovary. In the nectary regions located on the extension of the ribs of the ovary, stomata were very numerous. In the upper part of the nectary, stomata were arranged individually or in small clusters, whereas at its half- -height they formed stomatal areas. The stomata were at different growth stages. They were arranged in different directions. The stomata developed on the nectary surface according to the mosaic pattern. The stomata from the lower situated part of the nectary had a different structure than those occurring in the upper half of the nectary. The stomata in the nectaries of Rh. japonicum belong to the actinocytic type. The cuticle layer in the upper part of the nectary was better developed and had a characteristic sculpture, whereas in the lower part it was smooth.

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Comparison of features of the epidermis and the size of the floral nectary in four species of the genus Cotoneaster Med.

Acta Agrobotanica ◽

10.5586/aa.2011.045 ◽

2012 ◽

Vol 64 (4) ◽

pp. 47-58 ◽

Cited By ~ 2

Author(s):

Mirosława Chwil ◽

Elżbieta Weryszko-Chmielewska

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Stomatal Density ◽

Epidermal Cells ◽

Floral Nectary ◽

Cuticular Ornamentation ◽

Floral Nectaries ◽

Nectariferous Tissue ◽

Nectar Flow ◽

Scanning Electron

The investigations involved four species of the Cotoneaster genus: C. divaricatus, C. horizontalis, C. lucidus, C. praecox, which are commonly grown for decorative purposes. In Poland, these plants bloom in May and June and are a source of abundant spring nectar flow for insects. The floral nectaries of the above-mentioned species were examined using stereoscopic, light, and scanning electron microscopy in order to assess their size and epidermal microstructure. In the plants studied, the upper part of the hypanthium is lined by nectariferous tissue. The nectaries in the four species vary in terms of their sizes. Nectar is secreted onto the surface of the epidermis through anomocytic, slightly elongated or circular stomata. The largest stomata on the nectary epidermis were found in the flowers of C. horizontalis, and the smallest ones in C. divaricatus.Their size and location in relation to other epidermal cells were taxon-specific. The highest density of stomata in the nectary epidermis was found in C. divaricatus (205 per mm2), whereas C. horizontalis flowers exhibited the lowest (98 per mm2) stomatal density. The cuticular ornamentation on the nectary epidermis surface was diverse. The stomatal indices calculated for the nectary epidermis were considerably lower than for the leaves in the particular species.

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Anatomy of the floral, bract, and foliar nectaries of Triumfetta semitriloba (Tiliaceae)

Canadian Journal of Botany ◽

10.1139/b05-001 ◽

2005 ◽

Vol 83 (3) ◽

pp. 279-286 ◽

Cited By ~ 23

Author(s):

Carlos André Espolador Leitão ◽

Renata Maria Strozi Alves Meira ◽

Aristéa Alves Azevedo ◽

João Marcos de Araújo ◽

Kellen Lagares Ferreira Silva ◽

...

Keyword(s):

Phenolic Compounds ◽

Type A ◽

Structural Features ◽

Floral Bract ◽

Secretory Structures ◽

Floral Nectary ◽

Foliar Anatomy ◽

Weedy Species ◽

Floral Nectaries

Triumfetta semitriloba Jacq. (Tiliaceae) is a tropical weedy species with floral nectaries and glands located at the margins of the leaves. The objectives of this work were to describe the anatomy of these secretory structures and to analyze their exudates. Sucrose, glucose, and fructose were identified in the product released by these secretory structures, characterizing them as nectaries. The nectaries of T. semitriloba are of a specialized type; a secretory epidermis comprised of pluricellular and multiserial nectariferous trichomes covers a nectariferous parenchyma, vascularized by phloem and xylem. A mass of phenolic compounds occurs in the head cells of the nectariferous trichomes of the foliar and bract nectaries; however, it is absent in trichomes of the floral nectary. The leaf and bract nectaries differed from those from flowers in their length and diameter. Structural features of the nectaries of T. semitriloba are typical of other taxa of the Malvales.Key words: foliar anatomy, histochemistry, Malvales, nectaries, Tiliaceae, Triumfetta semitriloba.

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Oospore dimensions and wall ornamentation in Chara braunii

Biologia ◽

10.2478/s11756-008-0079-y ◽

2008 ◽

Vol 63 (4) ◽

Author(s):

Patrycja Boszke ◽

Mariusz Pełechaty ◽

Andrzej Pukacz

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Local Population ◽

Polar Axis ◽

Morphological Features ◽

Cylindrical Shape ◽

Reproductive Structures ◽

Equatorial Diameter ◽

Variable Character ◽

Scanning Electron

AbstractMorphological features of oospores of a rarely noted species Chara braunii Gmel. were examined in a local population (fishpond near Tuplice village, Ziemia Lubuska region, mid-western Poland). The largest polar axis (LPA, length), largest equatorial diameter (LED, width), isopolarity index (ISI = LPA/LED* 100), and the number of ridges and width of fossa of 90 oospores were measured. Additionally, the oospore wall ornamentation pattern was examined by means of scanning electron microscopy (SEM). As a result, a cylindrical shape and the lack of so-called “shoulder” were found. Oospore length and width ranged between 466.8–600.1 µm and 250.1–366.7 µm, respectively, with the ISI index values between 148 and 213. The number of ridges was 8–10 and the width of fossa varied between 50.0 and 66.7 µm. The oospore width appeared to be the most changeable feature, whereas, by contrast, the number of ridges was the least variable character. Wall ornamentation can be described as tuberculate and a ribbon was present on the ridges. As a comparative material for the study performed, 9 oospores from Professor Izabela Dąmbska’s Collection of Charophytes of Poland were measured. It was evidenced that variation ranges of most of the features of Chara braunii oospores from Tuplice fishpond are similar to those of Professor Dąmbska’s herbarium materials and to data reported by authors from other countries as well. The morphology of reproductive structures does not follow the variation of thalli characteristics.

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The study of proventricular micromorphological characterization of ten Grylloidea species (Orthoptera: Grylloidea) from China

Zootaxa ◽

10.11646/zootaxa.2906.1.3 ◽

2011 ◽

Vol 2906 (1) ◽

pp. 52

Author(s):

XIAOQIANG LI ◽

BINGZHONG REN ◽

YUTING ZOU ◽

JIAN ZHANG ◽

YINLIANG WANG

Keyword(s):

Electron Microscopy ◽

Clustering Analysis ◽

Feeding Habits ◽

Critical Value ◽

Morphological Characterization ◽

Species Relationships ◽

Future Studies ◽

Selection Of ◽

Scanning Electron

The present study compares the proventricular morphology, analyzed under optic microscope and scanning electron microscopy (SEM), among ten Grylloidea species. The result showed that the size of proventriculus was of critical value. Internally, the main differences were the number of sclerotized appendix (sa), middle denticles (md) and lateral denticles (ld), and the structure of lateral teeth (lt). In addition, we analyzed the crickets’ feeding habits and note that the the proventriculus possesses highly sclerotized projections which act in the selection of victuals. The morphology of proventriculus is closely related to feeding habits. A clustering analysis of seven features of the proventriculus was constructed. It revealed that the proventriculus had significance for taxonomy and species relationships. Observations on morphological characterization of proventricular morphology will be useful in future studies of the feeding habits and phylogeny of crickets.

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LTR retrotransposons in the dioecious plant Silene latifolia

Genome ◽

10.1139/g02-026 ◽

2002 ◽

Vol 45 (4) ◽

pp. 745-751 ◽

Cited By ~ 28

Author(s):

Sachihiro Matsunaga ◽

Fumi Yagisawa ◽

Maki Yamamoto ◽

Wakana Uchida ◽

Shunsuke Nakao ◽

...

Keyword(s):

Sex Chromosomes ◽

Evolutionary Dynamics ◽

Sex Chromosome ◽

Silene Latifolia ◽

Ltr Retrotransposons ◽

Dioecious Plant ◽

Dioecious Species ◽

Y Chromosomes ◽

Genus Silene ◽

Silene Species

Conserved domains of two types of LTR retrotransposons, Ty1copia- and Ty3gypsy-like retrotransposons, were isolated from the dioecious plant Silene latifolia, whose sex is determined by X and Y chromosomes. Southern hybridization analyses using these retrotransposons as probes resulted in identical patterns from male and female genomes. Fluorescence in situ hybridization indicated that these retrotransposons do not accumulate specifically in the sex chromosomes. These results suggest that recombination between the sex chromosomes of S. latifolia has not been severely reduced. Conserved reverse transcriptase regions of Ty1copia-like retrotransposons were isolated from 13 different Silene species and classified into two major families. Their categorization suggests that parallel divergence of the Ty1copia-like retrotransposons occurred during the differentiation of Silene species. Most functional retrotransposons from three dioecious species, S. latifolia, S. dioica, and S. diclinis, fell into two clusters. The evolutionary dynamics of retrotransposons implies that, in the genus Silene, dioecious species evolved recently from gynodioecious species.Key words: retrotransposon, dioecious plant, sex chromosome.

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Y chromosome specific markers and the evolution of dioecy in the genus Silene

Genome ◽

10.1139/g97-094 ◽

1998 ◽

Vol 41 (2) ◽

pp. 141-147 ◽

Cited By ~ 17

Author(s):

Y Hi Zhang ◽

Veronica S Stilio ◽

Farah Rehman ◽

Amy Avery ◽

David Mulcahy ◽

...

Keyword(s):

Y Chromosome ◽

Sex Chromosomes ◽

Silene Latifolia ◽

Dioecious Species ◽

Sequence Characterized Amplified Region ◽

Y Chromosomes ◽

Heteromorphic Sex Chromosomes ◽

Males And Females ◽

Genus Silene ◽

Evolution Of Dioecy

Sex determination in plants has been most thoroughly investigated in Silene latifolia, a dioecious species possessing heteromorphic sex chromosomes. We have identified several new Y chromosome linked RAPD markers and converted these to more reliable sequence characterized amplified region (SCAR) markers by cloning the RAPD fragments and developing longer primers. Of the primer pairs for seven SCARs, five amplify a single, unique fragment from the DNA of male S. latifolia. Two sets of primers also amplify additional fragments common to males and females. Homology between the X and Y chromosomes is sufficient to allow the amplification of fragments from females under less stringent PCR conditions. Five of the SCARs also distinguish between the sexes of closely related dioecious taxa of the section Elisanthe, but not between the sexes of distantly related dioecious species. These markers will be useful for continued investigations into the evolution of sex, phylogenetic relationships among taxa, and population dynamics of sex ratios in the genus Silene.Key words: Melandrium, RAPDs, sex chromosomes, SCARs.

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Morphological aspects of immature stages of Migonemyia migonei (Diptera: Psychodidae, Phlebotominae), an important vector of Leishmaniosis in South America, described by scanning electron microscopy

PLoS ONE ◽

10.1371/journal.pone.0242163 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0242163

Author(s):

Eric Fabrício Marialva ◽

Nágila F. Secundino ◽

Fernando F. Fernandes ◽

Helena R. C. Araújo ◽

Claudia M. Ríos-Velásquez ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

South America ◽

Leishmania Infantum ◽

Immature Stages ◽

Vector Species ◽

Future Studies ◽

Larval Stages ◽

Morphological Aspects ◽

Scanning Electron

We describe the immature stages of Migonemyia migonei, which is the vector of Leishmania (Viannia) braziliensis, the etiological agent of cutaneous leishmaniasis in South America, and a putative vector of Leishmania infantum chagasi. Scanning Electron Microscopy (SEM) was used to refine the description of the structures of the egg, all instar larvae, and the pupa. The eggs have polygonal cells on the egg exochorion, and differences between larval and pupal chaetotaxy have been highlighted. Different sensillary subtypes—trichoidea, basiconica, coelonica and campanoformia—were observed in the larval stages. The results presented herein contribute to the taxonomy of Mg. migonei and may contribute to future studies on the phylogeny of this important vector species.

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New perspectives in nectar evolution and ecology: simple alimentary reward or a complex multiorganism interaction?

Acta Agrobotanica ◽

10.5586/aa.1704 ◽

2017 ◽

Vol 70 (1) ◽

Cited By ~ 17

Author(s):

Massimo Nepi

Keyword(s):

Amino Acids ◽

Vascular Plants ◽

Amino Acid Content ◽

Secondary Compounds ◽

Indirect Defense ◽

Plant Tissues ◽

Plant Fitness ◽

Reproductive Structures ◽

Floral Nectaries ◽

Plant Animal Interactions

Floral and extra-floral nectars are secretions elaborated by specific organs (nectaries) that can be associated with plant reproductive structures (the so-called floral nectaries found only in angiosperms) or vegetative parts (extrafloral nectaries). These secretions are common in terrestrial vascular plants, especially angiosperms. Although gymnosperms do not seem to have true nectar, their ovular secretions may share evolutionary links with angiosperm nectar. Nectar is generally involved in interactions with animals and by virtue of its sugar and amino acid content, it has been considered a reward offered by plants to animals in exchange for benefits, mainly pollination and indirect defense against herbivores. These relationships are often cited as examples of classical mutualistic interactions. Nonetheless, recent studies dealing with compounds less abundant than sugars and amino acids challenge this view and suggest that nectar is much more complex than simply a reward in the form of food. Nectar proteins (nectarins) and nectar secondary compounds have no primary nutritious function but are involved in plant–animal relationships in other ways. Nectarins protect against proliferation of microorganisms and infection of plant tissues by pathogens. Nectar secondary compounds can be involved in modulating the behavior of nectar feeders, maximizing benefits for the plant. Nectar-dwelling microorganisms (mainly yeasts) were recently revealed to be a third partner in the scenario of plant–animal interactions mediated by nectar. There is evidence that yeast has a remarkable impact on nectar feeder behavior, although the effects on plant fitness have not yet been clearly assessed.

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