Taxonomic application of macro and micro morphological characters of seeds in Astragalus L. (Galegeae, Fabaceae) in India

Phytotaxa ◽  
2021 ◽  
Vol 502 (2) ◽  
pp. 191-207
Author(s):  
SHIVANI KASHYAP ◽  
CHANDAN KUMAR SAHU ◽  
ROHIT KUMAR VERMA ◽  
LAL BABU CHAUDHARY

Due to large size and enormous morphological plasticity, the taxonomy of the genus Astragalus is very complex and challenging. The identification and grouping of species chiefly based on macromorphological characters become sometimes difficult in the genus. In the present study, the micromorphology of the seeds of 30 species belonging to 14 sections of Astragalus from India has been examined applying scanning electron microscopy (SEM) along with light microscopy (LM) to evaluate their role in identification and classification. Attention was paid to colour, shape, size and surface of seeds. The overall size of the seeds ranges from 1.5–3.2 × 0.8–2.2 mm. The shape of the seeds is cordiform, deltoid, mitiform, orbicular, ovoid and reniform. The colour of seeds varies from brown to blackish-brown to black. Papillose, reticulate, ribbed, rugulate and stellate patterns were observed on the seed coat surface (spermoderm) among different species. The study reveals that the seed coat ornamentations have evolved differently among species and do not support the subgeneric and sectional divisions of the genus. However, they add an additional feature to the individual species, which may help in identification in combination with other macro-morphological features.

2015 ◽  
Vol 60 (2) ◽  
pp. 119-126 ◽  
Author(s):  
Jolanta Piątek

AbstractA new silica-scaled chrysophyte species, Mallomonas camerunensis J. Piątek, is described and illustrated from a shallow puddle in the Guineo-Congolian rainforest in Cameroon. This species belongs to section Papillosae and series Papillosa. It is similar to other Mallomonas species placed in Papillosa, such as M. binocularis Siver, M. calceolus D. E. Bradley, M. delanciana Siver, M. kalinae Řezáčová, M. papillosa K. Harris & D. E. Bradley, M. paxillata (D. E. Bradley) L. Ş. Péterfi & Momeu, M. rasilis Dürrschm. and M. tropica Dürrschm. & Croome, but differs from them in several morphological characters warranting recognition as a distinct species. The dome of M. camerunensis is clearly delimited and ornamented with papillae and ribs. The scales lack an anterior submarginal rib, while the posterior rim and V-rib are smooth and unornamented. The shield is thickly ornamented with papillae (18–22 papillae per scale width). The species is described and illustrated using light microscopy and scanning electron microscopy.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jolanta Piątek ◽  
Joanna Lenarczyk ◽  
Marcin Piątek

Abstract The chrysophyte genus Dinobryon Ehrenberg consists of 44 taxa, which occur in freshwaters, rarely marine waters, mostly in temperate regions of the world. The taxa of Dinobryon produce characteristic solitary or dendroid colonies and resting stages called stomatocysts. Only 20 Dinobryon taxa have information on produced stomatocysts and only four stomatocysts are reliably linked with vegetative stages using modern identification standards employing scanning electron microscopy (SEM) analyses. In this study, an encysted material of Dinobryon pediforme (Lemmermann) Steinecke was collected in two lakes in contrasting regions of Poland. Light microscopy (LM) and scanning electron microscopy (SEM) analyses revealed that Dinobryon pediforme produces stomatocyst #61, Piątek J. that is described here as new morphotype following the International Statospore Working Group (ISWG) guidelines. This raises to five the number of reliable links between vegetative stages of Dinobryon species and corresponding stomatocysts. Phenotypic similarities between Dinobryon species and their stomatocysts, analysed for five reliably established links, showed no relationships in size and shape between loricas and stomatocysts belonging to the same species. The morphological characters of loricas and stomatocysts mapped onto the phylogenetic tree of the five Dinobryon species revealed only little congruence between their morphology and phylogenetic relationships.


Phytotaxa ◽  
2018 ◽  
Vol 357 (1) ◽  
pp. 41 ◽  
Author(s):  
JULIEN MARQUIE ◽  
RENE LE COHU ◽  
MICHEL COSTE

During a recent survey of epilithic diatoms in running waters of New Caledonia, two unknown Adlafia Moser, Lange-Bertalot & Metzeltin species were found. Both species are described as new based on light and scanning electron microscopy (LM and SEM). Adlafia moseri sp. nov., is characterised by its margins morphology, its large size and its low stria density, clearly visible in LM. Adlafia tjibaoui sp. nov. shows a very long internal intermissio with curved proximal raphe endings and a very high stria density. Since the generitype Adlafia muscora (Kociolek & de Reviers) Moser, Lange-Bertalot & Metzeltin was poorly described, its diagnosis is emended based on more detailed scanning electron microscopy observations. Kobayasiella saxicola (Manguin) Lange-Bertalot, only described in light microscopy, occurs frequently in some running waters in New Caledonia. An emended description of this taxon is likewise proposed based on additional SEM data.


2014 ◽  
Vol 65 (1-2) ◽  
pp. 171-174
Author(s):  
Leszek Trząski ◽  
Jagna Karcz ◽  
Alicja Miszta

Flowers and seeds of Landsberg <em>erecta</em> (Ler) ecotype and NW4 mutant were studied by light microscopy and scanning electron microscopy to reveal characteristic features of their structure. The NW4 mutant flowers differ from Ler mainly in presence of two bract-like sepals with complicated vasculature and a variable number of secondary flowers. In the two outer whorls of NW4 flower, variable number of transformed stamen-, petal-, sepal- and style-like elements also occur. The NW4 mutant seeds are characterized by the absence of mucilage around the surface and a deviating seed coat morphology.


2017 ◽  
pp. 17
Author(s):  
Aida Carrillo-Ocampo ◽  
E. Mark Engleman

The seed of huauzontle (Chenopodium berlandieri ssp. nuttalliae) was studied by light microscopy and scanning electron microscopy. When the outer integument arises around the young ovule, instead of covering the inner integument and the nucellus, it grows backwards and partially surrounds the funiculus . When the pericarp is removed from the mature fruit, the seed is straw colored, because only the tegmen covers the seed. The chalaza of this seed has the form of a truncate cone, with the elliptical base towards the nucellus. In this zone of contact between the chalaza and the nucellus. a cuticle is deposited that surrounds some cells and makes a three dimensional network. This chalazal network is in contact with a smooth nucellar cuticle that fom1s part of the seed coat. The inversion of the inner integument could represent a selected mutation during the process of domestication.


2021 ◽  
Vol 9 (2) ◽  
pp. 282-292
Author(s):  
Silvina S. Garralla ◽  
Lilia R. Mautino

The pollen morphology of 13 native taxa of the Rutaceae from Argentina was studied under optical and scanning electron microscopy to provide new data that would allow delimiting these taxa. The species considered were Balfourodendron riedelianum, Esenbeckia densiflora, E. febrifuga, E grandiflora, Helietta apiculata, Pilocarpus pennatifolius, Zanthoxylum caribaeum, Z. coco, Z. fagara, Z. petiolare, Z. rhoifolium, Z. riedelianum and Zanthoxylum rigidum ssp. hasslerianum. The general morphological characteristics of the pollen grain of these species are: radiosymmetric, isopolar; small, medium or large size; 3-colporate or 4-colporate; colpus with costa colpi; semitectate (reticulate, striate reticulate or striate). Sculpture, shape and size are the main characters that allow differentiating the studied taxa. Morphological characters among the species are discussed and a species key is presented.


Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

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).


Author(s):  
D. Johnson ◽  
P. Moriearty

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.


Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard

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.


2009 ◽  
Vol 18 (2) ◽  
pp. 191-195
Author(s):  
E.V. Soldatenko

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.


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