scholarly journals Seed morphometric characteristics of European species of Elatine (Elatinaceae)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3399 ◽  
Author(s):  
Agnieszka Popiela ◽  
Andrzej Łysko ◽  
Bożenna Białecka ◽  
Magdalena Marta Bihun ◽  
Gábor Sramkó ◽  
...  

Elatine L. contains ca. 25 small, herbaceous, annual species distributed in ephemeral waters in both hemispheres. All species are amphibious and characterized by a high degree of morphological variability. The importance of seed morphology in Elatine taxonomy has been emphasized by many authors. The degree of seed curvature and seed coat reticulation have been traditionally considered very important in recognizing individual species of this genus. Seed morphometric characteristics of 10 Elatine species, including all European native taxa, are provided on the basis of material from two or three populations of each species. A total of 24–50 seeds were studied from each population, altogether 1,260 images were used for the morphometric study. In total, six parameters were measured from SEM pictures: object surface area, profile specific perimeter (object circuit), rectangle of the object (a) length, rectangle of the object (b) width, angle of the seed curvature, and number of pits in the seed coat counted in the middle row. Our study shows that the range of morphological variation of seeds in European species of Elatine is great, both between the species and the populations. Discrimination analysis showed that all six traits significantly differentiate the populations studied (λ = 0.001, p < 0.001), and the greatest contributions were “number of pits”, “rectangle_a”, and “the angle curvature”. Multidimensional scaling based on a correlation matrix of Mahalanobis distance of the six features studied revealed the greatest similarity between the three populations of E. alsinastrum, E. macropoda, and E. hexandra. Regarding interspecific differences, a Kruskal–Wallis tests showed that, in many cases, lack of statistically significant differences between species relative to the studied seed traits. If distinction of species is only based on seeds, especially if only a few seeds are evaluated, the following species pairs can be easily confused: E. alsinastrum and E. orthosperma, E. hexandra and E. macropoda, E. campylosperma and E. hydropiper, as well and E. gussonei and E. hungarica. We found no diversity in seed coat micromorphology within pits that could have potential taxonomic importance. An identification key and descriptions of species are provided on the basis of seeds traits.

Phytotaxa ◽  
2019 ◽  
Vol 387 (2) ◽  
pp. 105-118 ◽  
Author(s):  
ATEFEH PIRANI ◽  
SHAHIN ZARRE ◽  
RICHARD RABELER ◽  
MOSTAFA ASSADI ◽  
MOHAMMAD REZA JOHARCHI ◽  
...  

Acanthophyllum, with ca. 90 spiny cushion-forming species, is one of the largest genera of Caryophyllaceae. Although taxonomic utility of seed morphology has already been highlighted in different genera of Caryophyllaceae, the systematic value of seed characters in Acanthophyllum has not been adequately addressed. In order to evaluate the application of seed morphology in infrageneric classification of Acanthophyllum, we surveyed seed characters in the five Iranian sections of Acanthophyllum. Seed morphology of 32 accessions of Acanthophyllum representing 21 species and four sections were investigated using scanning electron microscopy. Seed morphological characters of two species from one additional section were included based on previous studies in the Caryophyllaceae. Seeds in the majority of examined species are oblong in outline. Five types of seed surface can be considered: reticulate, reticulate-papillate, colliculate, colliculate-papillate, and colliculate-columellate. Papillae type is a reliable character for separation of certain natural groups within Acanthophyllum. Seed features provided strong evidences for separating sections, especially the following ones: Acanthophyllum, Macrostegia and Pleiosperma, whose seeds showed a high degree of uniformity among the sampled species. Morphological characteristics of seeds were less useful for discriminating Acanthophyllum species. While seed characters are consistent within individual populations, they can vary among different populations of an individual species. Our results show that variation in seed morphological characters are in agreement with phylogenetic patterns within Acanthophyllum.


2020 ◽  
Vol 45 (3) ◽  
pp. 478-482
Author(s):  
Steven R. Manchester

Abstract—The type material on which the fossil genus name Ampelocissites was established in 1929 has been reexamined with the aid of X-ray micro-computed tomography (μ-CT) scanning and compared with seeds of extant taxa to assess the relationships of these fossils within the grape family, Vitaceae. The specimens were collected from a sandstone of late Paleocene or early Eocene age. Although originally inferred by Berry to be intermediate in morphology between Ampelocissus and Vitis, the newly revealed details of seed morphology indicate that these seeds represent instead the Ampelopsis clade. Digital cross sections show that the seed coat maintains its thickness over the external surfaces, but diminishes quickly in the ventral infolds. This feature, along with the elliptical chalaza and lack of an apical groove, indicate that Ampelocissites lytlensis Berry probably represents Ampelopsis or Nekemias (rather than Ampelocissus or Vitis) and that the generic name Ampelocissites may be useful for fossil seeds with morphology consistent with the Ampelopsis clade that lack sufficient characters to specify placement within one of these extant genera.


2019 ◽  
Vol 11 (1) ◽  
pp. 93-100
Author(s):  
T Ljubka ◽  
O Tsarenko ◽  
I Tymchenko

The investigation of macro- and micromorphological peculiarities of seeds of four species of genus Epipactis (Orchidaceae) of Ukrainian flora were carried out. The genus Epipactis is difficult in the in in taxonomic terms and for its representatives are characterized by polymorphism of morphological features of vegetative and generative organs of plants and ability of species to hybridize. The aim of the research was to perform a comparative morphological study of seeds of E. helleborine, E. albensis, E. palustris, E. purpurata and to determine carpological features that could more accurately identify species at the stage of fruiting. A high degree of variation in the shape of the seeds in different populations within the species and overlap of most quantitative carpological characteristics of studied species are noted. There were no significant differences in micromorphological features of the structure of the testa at species or population level. The reticulate surface of the testa is characteristic of all species, the cells of testa are mostly elongated, penta-hexagonal, individual cells almost isodiametric-pentagonal. From the micropillary to the chalasal end, a noticeable change in the shape and size of the seed coat cells is not observed. There are no intercellular spaces, the anticlinal walls of adjacent cells are intergrown and the boundaries between them become invisible. The outer periclinal walls have a single, mainly longitudinal thin ribbed thickenings. Anticlinal cell walls are thick, dense, smooth. The longitudinal Anticlinal walls are almost straight, transverse - straight or sometimes curved in some cells. Epicuticular deposits on the periclinal walls are absent. It is concluded that the use of macro and micromorphological characteristics of seeds of these species for clearer diagnosis at the stage of fruiting is low informative.


2007 ◽  
Vol 55 (6) ◽  
pp. 618 ◽  
Author(s):  
Kim N. Hamilton ◽  
Sarah E. Ashmore ◽  
Rod A. Drew ◽  
Hugh W. Pritchard

Combinational traits of seed size and seed-coat hardness in Citrus garrawayi (F.M.Bailey) (syn. of Microcitrus garrowayi) were investigated as markers for estimation of seed morphological and physiological maturity. Seed size (length) and coat hardness correlated well with changes in seed coat and embryo morphological development, dry-weight accumulation, decreases in moisture content and a significant increase in germinability. Seed moisture content decreased from 82 ± 1% in immature seeds to 40 ± 1% at seed maturation. The outer integument of immature seeds consisted of thin-walled epidermal fibres from which outgrowths of emerging protrusions were observed. In comparison, mature seed coats were characterised by the thickening of the cell walls of the epidermal fibres from which arose numerous protrusions covered by an extensive mucilage layer. Immature seeds, with incomplete embryo and seed-coat histodiffereniation, had a low mean germination percentage of 4 ± 4%. Premature seeds, with a differentiated embryonic axis, were capable of much higher levels of germination (51 ± 10%) before the attainment of mass maturity. Mature seeds, with the most well differentiated embryonic axis and maximum mean dry weight, had the significantly highest level of germination (88 ± 3%).


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.


2017 ◽  
Vol 73 (10) ◽  
pp. 661-665
Author(s):  
Katarzyna Olbrych ◽  
Karolina Barszcz ◽  
Bartłomiej Bartyzel ◽  
Tomasz Szara ◽  
Marta Kupczyńska

Summary The European bison belongs to endangered species. Its restitution requires a complete knowledge of the structure and function of its genital organs. The aim of this study was a histological and morphometric examination of the uterus of immature and adult females. Material for the study came from 55 females living in the Białowieża Forest. According to the Polish law, the post mortem use of tissues does not require an approval from an ethics committee. The animals were divided into 2 groups: group I included 36 prepubertal females aged from 2 months to 1.5 years, while group II consisted of 19 sexually mature females aged 2 to 20 years. The samples were stained with haematoxylin and eosin (H&E). Histological and morphometric examinations included measurements of the height of the epithelium, thickness of the endometrium, thickness of the myometrium, thickness of the inner and outer muscular layers, and thickness of the perimetrium. The results were analyzed using the STATISTICA 12.0™ software. Statistically significant differences were found between the two groups in all morphometric parameters examined. The results revealed a high degree of similarity of the histological structure of the uterus between European bison and domestic cattle.


2018 ◽  
Vol 36 (10) ◽  
pp. e01866 ◽  
Author(s):  
Balkrishna Ghimire ◽  
Mi Jin Jeong ◽  
Gang Uk Suh ◽  
Kweon Heo ◽  
Cheul Ho Lee
Keyword(s):  

2019 ◽  
Vol 94 (1) ◽  
pp. 115-130
Author(s):  
Timothy A. M. Ewin ◽  
Markus Martin ◽  
Phillip Isotalo ◽  
Samuel Zamora

AbstractRhenopyrgids are rare, turreted edrioasterid edrioasteroids from the lower Paleozoic with a distinctive and apparently conservative morphology. However, new, well-preserved rhenopyrgid edrioasteroid material from Canada, along with a review of described taxa, has revealed broader structural diversity in the oral surface and enabled a re-evaluation of rhenopyrgid functional morphology and paleoecology.The floor plates in Rhenopyrgus viviani n. sp., R. coronaeformis Rievers, 1961 and, R. flos Klug et al., 2008 are well fused to each other and the interradial oral plate and lack obvious sutures, thereby forming a single compound interradial plate. This differs from other rhenopyrgids where sutures are more apparent. Such fused oral surface construction is only otherwise seen in some derived edrioblastoids and in the cyathocystids, suggesting homoplasy.Our analysis further suggests that the suboral constriction could contract but the flexible pyrgate zone could not. Thus, specimens apparently lacking a sub-oral constriction should not necessarily be placed in separate genera within the Rhenopyrgidae. It also supports rhenopyrgids as epifaunal mud-stickers with only the bulbous, textured, entire holdfasts (coriaceous sacs) anchored within the substrate rather than as burrow dwellers or encrusters.Rhenopyrgus viviani n. sp. is described from the Telychian (lower Silurian) Jupiter Formation of Anticosti Island, Québec, Canada and is differentiated by a high degree of morphological variability of pedunculate plates, broader oral plates, and narrower distal ambulacral zones. Specimens lacking or with obscured diagnostic plates from the Ordovician of Montagne Noire, France, and the Ordovician and Silurian of Girvan, Scotland are also described.UUID: http://zoobank.org/7f81d67f-4155-4719-8a45-b278ad70739d


2019 ◽  
Vol 26 (2) ◽  
pp. 315-324
Author(s):  
Soghra Ramzi ◽  
Shahryar Saedi-Mehrvarz

Seed morphology of 12 Iranian endemic and subendemic species of Veronica was studied using scanning electron microscope (SEM). Seven qualitative and quantitative characters were measured using SEM micrographs and stereomicroscopy. The seed shape of most species is ovate and plano-convex. The size of seeds ranges from 1.25 x 0.75 mm in V. khorassanica to 2.5 x 1.75 mm in V. viscosa Boiss. The ornamentation of seed coat is reticulate-verrucate in V. khorassanica, V. czerniakowskiana, V. mazanderanae and V. rubrifolia, reticulate-rugate in V. acrotheca, V. aucheri, V. viscosa and V. intercedens, rugose in V. microcarpa, V. chionantha and V. rechingeri, and reticulate-porate in V. gaubae. The testa cells are polygonal in ten species and irregular in two species. Micromorphological characters of seeds are useful in specific and subspecific delimitations of Iranian Veronica.


2014 ◽  
Vol 35 (1) ◽  
pp. 15-18
Author(s):  
Piotr Szkudlarz

Abstract Hypericum elegans is a rare perennial distributed primarily in Central and Eastern Europe. Seed morphology and anatomy in H. elegans was studied on the basis of a seed sample from its only locality in Poland. Scanning electron microscopy revealed that the seed coat of mature seeds is composed basically of 3 cell layers: epidermal, subepidermal and sclerenchymatic. They are documented graphically here.


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