scholarly journals Anatomía de la semilla de cuatro especies mexicanas de Hippocratea (Celastraceae)

2017 ◽  
pp. 57
Author(s):  
Ma. Guadalupe Espinosa-Osornio ◽  
E. Mark Engleman
Keyword(s):  
Light Microscopy ◽  
Seed Coat ◽  
Vascular Bundle ◽  
The Body ◽  
Short Axis ◽  
Abaxial Surface ◽  
Adaxial Surface ◽  
Mature Seeds

The morphology and anatomy of mature seeds of H. acapulcensis, H. celastroides. H. excelsa y H. volubilis were studied by light microscopy. In all four species the seeds are winged and the wing is larger than the body that contains the embryo. The wing may be mostly membranous or mostly thickened by the abundance of isodiametric tracheoidal cells. The vascular bundle of the raphe passes longitudinally through the middle of the wing. Additionally, a bundle of elongate tracheoidal cells passes along one edge of the wing or close by it. The wing has zones thickened by an abW1dance of thick-walled isodiametric tracheoidal cells. The embryo is large with a short axis. The cotiledons are connate and mayor may not maintain the epidermis of the adaxial surface, but cuticle was observed only on the abaxial surface. The seed coat is fomed by an exotesta with tannins, a mesotesta of elongate tracheoidal cells and a tanniniferous endotegmen. There are two thick cuticles, one on the exotesta and one on the nucellus. There are from one to four layers of endosperm.

Comparative midrib anatomy of Monodora Dunal. and Isolona Engl. (Annonaceae) from West-central Africa

2020 ◽  
Vol 27 (2) ◽  
pp. 283-291
Author(s):  
Sunday Adebunmi Adeniran ◽  
Akeem Babalola Kadiri ◽  
James Dele Olowokudejo
Keyword(s):  
Light Microscopy ◽  
Vascular Bundle ◽  
Central Africa ◽  
Vascular Bundles ◽  
Abaxial Surface ◽  
West Central ◽  
Dichotomous Key ◽  
Plant Taxon

This article assessed midrib anatomical description of Isolona Dunal. And Monodora Engl. (Annonaceae) from West-Central Africa. Twelve species of tribe Monodoreae were investigated on the basis of micromorphology of midrib characters with the aid of light microscopy. The study provided important taxonomic characters which aid delineation of inter and infrageneric species within the duo genera. The generic features include centrally positioned, open collateral vascular bundle and furrow shaped midribs which are diagnostic to the genera.U shaped vascular bundles are present in most of the species with inviginating or expanded endings while marginal traces vary from 2 to 4. The presence of keel protrusion at abaxial surface established a closer affinity among M. angolensis, M. crispata, and M undulata with additional features species were delimited. Other variable useful features of midrib encountered are trichomes, parenchyma, collenchyma and sclerenchyma, and adaxial and abaxial shape. The midrib characters have been used to prepare an indented dichotomous key to delimit the species in the genera studied. Bangladesh J. Plant Taxon. 27(2): 283-291, 2020 (December)

Prevalence of the pit and antipit in the genus Glycine

1987 ◽  
Vol 45 ◽  
pp. 986-987
Author(s):  
R. W. Yaklich ◽  
E. L. Vigil ◽  
W. P. Wergin
Keyword(s):  
Amino Acids ◽  
Endoplasmic Reticulum ◽  
Glycine Max ◽  
Seed Coat ◽  
Cell Types ◽  
Abaxial Surface ◽  
Legume Seed ◽  
Initial Report ◽  
Cone Cells ◽  
Glycine Max L

The legume seed coat is the site of sucrose unloading and the metabolism of imported ureides and synthesis of amino acids for the developing embryo. The cell types directly responsible for these functions in the seed coat are not known. We recently described a convex layer of tissue on the inside surface of the soybean (Glycine max L. Merr.) seed coat that was termed “antipit” because it was in direct opposition to the concave pit on the abaxial surface of the cotyledon. Cone cells of the antipit contained numerous hypertrophied Golgi apparatus and laminated rough endoplasmic reticulum common to actively secreting cells. The initial report by Dzikowski (1936) described the morphology of the pit and antipit in G. max and found these structures in only 68 of the 169 seed accessions examined.

scholarly journals Asymbiotic germination of Vanilla planifolia in relation to the timing of seed collection and seed pretreatments

2021 ◽  
Vol 62 (1) ◽  
Author(s):  
Chih-Hsin Yeh ◽  
Kai-Yi Chen ◽  
Yung-I. Lee
Keyword(s):  
Seed Germination ◽  
Seed Development ◽  
Seed Coat ◽  
Germination Percentage ◽  
Vanilla Planifolia ◽  
Outermost Layer ◽  
Seed Collection ◽  
Seed Pretreatment ◽  
Immature Seeds ◽  
Mature Seeds

Abstract Background Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, propagation with seed germination of V. planifolia is intricate and unstable because the seed coat is extremely hard with strong hydrophobic nature. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla. Results We found that soaking mature seeds in 4% sodium hypochlorite solution from 75 to 90 min significantly increased germination. For the culture of immature seeds, the seed collection at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. Seeds at 60 DAP and subsequent stages germinated poorly. As the seed approached maturity, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope at maturity. On toluidine blue O staining, the wall of outer seed coat stained greenish blue, indicating the presence of phenolic compounds. As well, on Nile red staining, a cuticular substance was detected in the surface wall of the embryo proper and the innermost wall of the inner seed coat. Conclusion We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The window for successful germination of culturing immature seed was short. The quick accumulation of lignin, phenolics and/or phytomelanins in the seed coat may seriously inhibit seed germination after 45 DAP. As seeds matured, the thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, which may play an important role in inducing dormancy. Further studies covering different maturity of green capsules are required to understand the optimal seed maturity and germination of seeds.

Implications of body condition and seasonality on morphological and functional parameters of testes of Myotis nigricans (Chiroptera: Vespertilionidae)

2018 ◽  
Vol 30 (7) ◽  
pp. 1029
Author(s):  
Marcelo Ferreira ◽  
Aline Soldati ◽  
Sirlene S. S. Rodrigues ◽  
Laércio dos Anjos Benjamin
Keyword(s):  
Light Microscopy ◽  
Body Condition ◽  
Environmental Variables ◽  
Reproductive Strategies ◽  
Leydig Cells ◽  
Dry Season ◽  
The Body ◽  
Reproductive Capacity ◽  
Seminiferous Tubules ◽  
The Mean

The insectivorous bat Myotis nigricans is widely distributed throughout the Neotropics, including Brazil, and has a reproductive biology that is affected by climate and food availability. To evaluate the reproductive capacity of this species, morphofunctional parameters of the testes were correlated with environmental variables and the body condition of individuals captured. After bats had been killed, their testes were removed, fixed in Karnovsky’s fluid for 24 h and embedded in resin for evaluation by light microscopy. The mean annual tubulosomatic index (0.58%) and the percentage of seminiferous tubules in the testes (88.96%) were the highest ever recorded for the Order Chiroptera. The percentage of Leydig cells and volume of the cytoplasm of Leydig cells were higher in the rainy than dry season (80.62 ± 3.19% and 573.57 ± 166.95 μm, respectively; mean ± s.d.). Conversely, the percentage of nuclei of the Leydig cells in the dry season (26.17 ± 3.70%; mean ± s.d.) and the total number of Leydig cells (6.38 ± 1.84 × 109; mean ± s.d.) were higher in the dry season. The results of the present study could help in future conservation of these bats because they provide a better understanding of the bats’ reproductive strategies and how the species can adapt to changes.

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
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Seed Coat ◽  
Morphological Plasticity ◽  
Morphological Characters ◽  
Individual Species ◽  
Large Size ◽  
The Individual ◽  
Scanning Electron

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.

scholarly journals Asymbiotic Germination of Mature Seeds and the Seed Development of Vanilla Planifolia

2021 ◽  
Author(s):  
Chih-Hsin Yeh ◽  
Kai-Yi Chen ◽  
Yung-I Lee
Keyword(s):  
Cell Wall ◽  
Seed Germination ◽  
Seed Development ◽  
Seed Coat ◽  
Germination Percentage ◽  
Vanilla Planifolia ◽  
Outermost Layer ◽  
Seed Pretreatment ◽  
Immature Seeds ◽  
Mature Seeds

Abstract Background: Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, sexual propagation with seed germination of V. planifolia is intricate and unstable because of the extremely hard seed coat. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla.Results: We found that soaking mature seeds in 4 % sodium hypochlorite solution from 75 to 90 min significantly increased germination and that immature seeds collected at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. After 60 DAP, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope. These features matches the significant decreases of immature seed germination percentage after 60 DAP. Conclusion: We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, and might play an important role in seed dormancy of V. plantifolia.

Electrophysiology of Acanthocephalan Body Wall Muscles

1979 ◽  
Vol 82 (1) ◽  
pp. 273-280
Author(s):  
B. S. WONG ◽  
DONALD M. MILLER ◽  
T. T. DUNAGAN
Keyword(s):  
Light Microscopy ◽  
Intracellular Recording ◽  
Body Wall ◽  
Membrane Potentials ◽  
The Body ◽  
Spontaneous Potential ◽  
Body Wall Muscles ◽  
Macracanthorhynchus Hirudinaceus ◽  
Anterior Posterior

Body wall muscles of an acanthocephalan Macracanthorhynchus hirudinaceus were studied by means of scanning and light microscopy and intracellular recording of potentials. Three types of spontaneous potential changes were found: larger (L) potentials which usually exhibited overshoot and were as large as 65 mV; smaller symmetric (A) potentials approximately 15 mV in amplitude; and even smaller asymmetric (S) potentials which sometimes reached 10 mV. The potentials recorded depended upon the position of the electrode in the anterior-posterior, as well as the medialateral, axis. Tetrodotoxin eliminated L but not S potentials. Ouabain lengthened the time for depolarization of L potentials and depolarized the membrane potentials. It is suggested that the rete system activates the body wall muscles in Acanthocephala.

Pleopeltis pleopeltifolia (Polypodiopsida, Polypodiaceae), a poikilochlorophyllous desiccation-tolerant fern: anatomical, biochemical and physiological responses during water stress

2014 ◽  
Vol 62 (8) ◽  
pp. 647 ◽  
Author(s):  
Ana Paula Lorenzen Voytena ◽  
Bruno Degaspari Minardi ◽  
José Bonomi Barufi ◽  
Marisa Santos ◽  
Áurea Maria Randi
Keyword(s):  
Cell Walls ◽  
Sugar Content ◽  
Longitudinal Direction ◽  
Photosynthetic Parameters ◽  
Palisade Parenchyma ◽  
Abaxial Surface ◽  
Adaxial Surface ◽  
Anomocytic Stomata ◽  
Relevant Role ◽  
Notable Increase

While many ferns have been described as desiccation tolerant (DT), few studies have reported on the mechanisms they use to survive cell desiccation. Among the species belonging to the genus Pleopeltis, P. pleopeltifolia (Raddi) Alston (Polypodiopsida, Polypodiaceae) is a DT species endemic to Brazil. So as to better characterise the mechanisms of desiccation tolerance in ferns, the present study aimed to analyse frond anatomy and physiological changes associated with desiccation and rehydration of P. pleopeltifolia. Fronds are dorsiventral, with uniseriate epidermis. The epidermal cells have various shapes, tending to stretch in the longitudinal direction of the frond. Anticlinal cell walls are sinuous, and periclinal cell walls are convex. Anomocytic stomata are restricted to the abaxial surface. Trichome-type scales are found on both sides of the frond and may play a relevant role in rehydration of this plant when water is available. The mesophyll of the frond consists of palisade parenchyma, tending to a bistratified adaxial surface and spongy parenchyma on abaxial surface. The cuticle on the adaxial surface is conspicuous, ensuring better control of internal water balance. For physiological analyses, sporophytes were subjected to desiccation for 0, 5, 10 and 15 days and rehydration for 1 day. Sporophytes showed a sharp decline in water content when kept without irrigation, reaching 9.6% after 15 days, in addition to wilting and frond rolling. A significant increase in sugar content in fronds was noticeable during desiccation, which may favour a possible osmotic adjustment and vitrification. A notable increase in proline content during rehydration was observed in fronds. During the five initial days of desiccation, the chlorophyll and carotenoid contents decreased abruptly, but after 1 day of rehydration, they had partly recovered. The photosynthetic parameters analysed by fluorescence of chlorophyll a ceased completely after 15 days of desiccation but they had recovered near to pre-desiccation levels after 1 day of rehydration.

scholarly journals Seed morphology and anatomy of Hypericum elegans Steph. ex Willd.

2014 ◽  
Vol 35 (1) ◽  
pp. 15-18
Author(s):  
Piotr Szkudlarz
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Eastern Europe ◽  
Seed Coat ◽  
Central And Eastern Europe ◽  
Seed Morphology ◽  
Seed Sample ◽  
Cell Layers ◽  
Mature Seeds ◽  
Scanning Electron

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.

Two new species of Graffenrieda (Melastomataceae, Merianieae) from the Amazon Rainforest

Phytotaxa ◽  
2016 ◽  
Vol 267 (1) ◽  
pp. 77 ◽  
Author(s):  
LAÍCE FERNANDA GOMES DE LIMA ◽  
JOSÉ FERNANDO ANDRADE BAUMGRATZ ◽  
EIMEAR NIC LUGHADHA ◽  
JOÃO UBIRATAN MOREIRA DOS SANTOS
Keyword(s):  
New Species ◽  
Conservation Status ◽  
The State ◽  
Amazon Rainforest ◽  
Similar Species ◽  
Abaxial Surface ◽  
Adaxial Surface ◽  
Two New Species

Two new species of Graffenrieda are described from the Amazon rainforest. Graffenrieda maturaca is characterized mainly by its leaves which are dull on the adaxial surface, chartaceous, narrowly elliptic to oblanceolate, and apparently uni-nerved, with only the median acrodromous vein evident. This species has been collected only at Serra de Maturacá, in the state of Amazonas, Brazil. Graffenrieda goldenbergii is distinguished mainly by the pulverulent, whitish, early caducous indumentum of the rachis, pedicel, hypanthium and calyx, by the abaxial surface of the leaves which is moderately lepidote, with trichomes ca. 0.2 mm diam., by the irregularly valvate calyx, and by the membranaceous, costate, not sulcate fruits. This species has been collected in the state of Acre, Brazil, and in the Province and District of Lama in Peru. Both species are illustrated, compared with similar species, and their conservation status is discussed.

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