scholarly journals Different ways to obtain similar results: the development of the corolla and epipetaly in Rubieae (Rubioideae, Rubiaceae)

2020 ◽  
Vol 153 (3) ◽  
pp. 466-486
Author(s):  
Alexander Vrijdaghs ◽  
Erik Smets ◽  
Petra De Block
Keyword(s):  
Light Microscopy ◽  
19Th Century ◽  
Floral Development ◽  
Corolla Tube ◽  
Sensu Stricto ◽  
Herbaceous Plants ◽  
Floral Ontogeny ◽  
Developmental Processes ◽  
Postgenital Fusion ◽  
Scanning Electron

Background and aims – Rubieae is a tribe in the subfamily Rubioideae characterised by herbaceous plants with verticillate leaves and flowers with a rudimentary or absent calyx and a short, cup-shaped corolla. This is in contrast to the flowers of most other Rubiaceae, in which the tubular corolla is longer than the corolla lobes. Also, the description by Payer, a French 19th century pioneer of floral ontogenetic research, of the floral development in Asperula, Galium, and Rubia deviates from recent insights about the development of tubular corollas, which are based on investigations of flowers of tropical Rubiaceae. Tubular corollas are currently considered as resulting from the development of underlying annular intercalary meristems, whereas Payer explained the tubular corollas in the three taxa by postgenital fusion. We therefore tested both hypotheses in six Rubieae genera, including the three taxa studied by Payer.Methods – Floral ontogeny of ten species in six Rubieae genera based on scanning electron (SEM) and light microscopy (LM). Conclusions – Our results suggest that, in all species studied, the mature phenotype of the corolla as well as the epipetaly of the stamens is caused by a combination of three developmental processes (the development of a stamen-corolla tube, the development of a corolla tube sensu stricto, and postgenital fusion), and the relative moment of activation of each of these processes during floral development (plastochron variation or heterochrony).

The floral development of Monococcus echinophorus (Phytolaccaceae)

1997 ◽  
Vol 75 (11) ◽  
pp. 1941-1950 ◽  
Author(s):  
P. F. Vanvinckenroye ◽  
L. P. Ronse Decraene ◽  
E. F. Smets
Keyword(s):  
Electron Microscope ◽  
Floral Development ◽  
Variable Number ◽  
Monotypic Genus ◽  
Floral Ontogeny ◽  
Short Style ◽  
Close Relationship ◽  
Median Position ◽  
Relationship Of ◽  
Scanning Electron

The floral ontogeny of the monotypic genus Monococcus (Phytolaccaceae) is investigated with the scanning electron microscope. Flowers arise on pendent racemes and are preceded by a bract and two bracteoles arising successively. In both staminate and pistillate flowers four sepals are incepted in diagonal position. In the staminate flowers four alternisepalous stamens are initiated successively. Further stamen inception occurs centrifugally and runs concomitant with peripheral growth of the receptacle. This centrifugal stamen initiation is interpreted phylogenetically as a secondary increase and is expressed by the appearance of four triplets. Initiation of a variable number of outermost stamens (0–8) occurs mostly in the latero-abaxial region of the flower. In staminate flowers there is no trace of a gynoecium. In pistillate flowers a gynoecium primordium arises centrally and grows into a monocarpellate structure. Later, hooked bristles arise on the carpel flanks while a short style is produced bearing a distal tangle of long hairs. A close relationship of Monococcus with Petiveria is confirmed; similarities include the median position of the prophylls, the diagonal position of four sepals, the sequential inception of four alternisepalous stamens, and the fruits with adaptations for exozoochory. Key words: androecium, floral ontogeny, Monococcus, Phytolaccaceae, Rivinoideae.

Floral development and anatomy of two species of Aechmea (Bromeliaceae, Bromelioideae)

2020 ◽  
Vol 194 (2) ◽  
pp. 221-238
Author(s):  
Sandra Santa-Rosa ◽  
Leonardo M Versieux ◽  
Monica Lanzoni Rossi ◽  
Adriana Pinheiro Martinelli
Keyword(s):  
Light Microscopy ◽  
Reproductive Biology ◽  
Floral Development ◽  
Floral Anatomy ◽  
Floral Buds ◽  
Large Genus ◽  
Electron And Light Microscopy ◽  
Appendage Formation ◽  
Scanning Electron

Abstract Aechmea (Bromeliaceae) is a large genus with controversial systematics and distinct flower shapes and pollinators. We explored floral anatomy and development in two Aechmea spp. belonging to different subgenera to contribute useful information on reproductive biology and taxonomy. We examined floral buds using scanning electron and light microscopy to characterize the development of septal nectaries, petal appendages, ovules, stamens and carpels. In A. gamosepala, we confirmed that the petal appendages develop late, whereas in A. correia-araujoi they develop earlier during floral development. Petal appendage formation included positional changes, possibly affecting floral attributes and visitation by insects, rather than vertebrates. Nectar is released through three basal orifices distally on the ovary, and here we document the link between the nectary region, through discrete canals, upward to the conduplicate lobes of the wet stigma. Improved understanding of the floral development and morphology of Aechmea may help to explain the existence of polymorphic flowers in this genus and may have implications for studies on interactions with pollinators and systematics.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

The Broad Applications of the Scanning Electron Microscope

1969 ◽  
Vol 27 ◽  
pp. 20-21
Author(s):  
C. T. Nightingale ◽  
S. E. Summers ◽  
T. P. Turnbull
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscopy ◽  
Surface Topography ◽  
Great Depth ◽  
Resolving Power ◽  
Depth Of Field ◽  
Pictorial Representations ◽  
Scanning Electron

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.

Examination of Schistosome Cercariae and Schistosomules by Scanning Electron Microscopy

1969 ◽  
Vol 27 ◽  
pp. 50-51
Author(s):  
D. Johnson ◽  
P. Moriearty
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Light Microscopy ◽  
Surface Structure ◽  
Extensive Study ◽  
Scanning Microscopy ◽  
Host Parasite ◽  
Conventional Electron Microscopy ◽  
Scanning Electron

Since several species of Schistosoma, or blood fluke, parasitize man, these trematodes have been subjected to extensive study. Light microscopy and conventional electron microscopy have yielded much information about the morphology of the various stages; however, scanning electron microscopy has been little utilized for this purpose. As the figures demonstrate, scanning microscopy is particularly helpful in studying at high resolution characteristics of surface structure, which are important in determining host-parasite relationships.

SEM Observations on the Germination of Euonymous Americanus

1985 ◽  
Vol 43 ◽  
pp. 508-509
Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Filter Paper ◽  
Room Temperature ◽  
Food Source ◽  
Environmental Chamber ◽  
Dormant Stage ◽  
Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

New diagnostic characters of Kolhymorbis angarensis (Dybowski & Grochmalicki, 1925) (Gastropoda: Pulmonata: Planorbidae)

2009 ◽  
Vol 18 (2) ◽  
pp. 191-195
Author(s):  
E.V. Soldatenko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Diagnostic Characters ◽  
Copulatory Apparatus ◽  
Scanning Electron

The radula morphology and the anatomy of the copulatory apparatus in Kolhymorbis angarensis were examined using light microscopy, scanning electron microscopy (SEM) and histological methods. Kolhymorbis angarensis was shown to have the stylet and the penial sac with a glandular appendage (flagellum), the characteristics, previously unknown for any species of this genus. The significance of these findings for the taxonomy of the genus is discussed.

A Comparative Study of Trichomes in Angophora Cav. And Eucalyptus L'hérit. - A Question of Homology

1984 ◽  
Vol 32 (5) ◽  
pp. 561 ◽  
Author(s):  
PY Ladiges
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Comparative Study ◽  
Light Microscopy ◽  
Evolutionary Trends ◽  
Oil Glands ◽  
Ancestral Condition ◽  
Scanning Electron

The trichomes of Angophora and Eucalyptus are illustrated from scanning electron microscopy and light microscopy, and evolutionary trends are discussed. Bristle glands of Angophora and Eucalyptus subgen. Blakella and Corymbia are emergent oil glands of varying lengths. Emergent oil glands occur in all other Eucalyptus subgenera but they are most conspicuous in Blakella, Corymbia and Angophora, in which they are characterized by four cap cells each ornamented with micropapillae. Hairs in Angophora are unique, being multicellular; they are also uniseriate and scattered on the epidermis. In contrast, hairs in Eucalyptus are simple extensions, short or long, of the cells on the sides of or the cap cells of the emergent oil glands, and they are not homologous with those of Angophora. Eucalyptus setosa (subgen. Blakella) and E. brockwayi (subgen. Symphyomyrtus) are two exceptions, having unicellular hairs on the epidermis, not associated with oil glands. It is suggested that this is an ancestral condition (or secondary reversal to it).

Sign in / Sign up

Export Citation Format

Share Document