scholarly journals Pollen morphology of some species of the genus Quercus L. (Fagaceae) in the Southern Caucasus and adjacent areas

2020 ◽  
pp. 1-42
Author(s):  
Alla Hayrapetyan ◽  
Angela A. Bruch
Keyword(s):  
Mediterranean Region ◽  
Introgressive Hybridization ◽  
Pollen Grains ◽  
Morphological Type ◽  
The Caucasus ◽  
Modern Species ◽  
Pollen Surface ◽  
Exine Ornamentation ◽  
Southern Caucasus ◽  
High Degree

The palynomorphology of 19 modern species of the genus Quercus L. native to Armenia and adjacent regions, including the Caucasus and Transcaucasia, the Mediterranean region (especially Turkey), as well as Iran, Iraq and Afghanistan, was studied using light microscopy (LM) and scanning electron microscopy (SEM). The work revealed two main types of apertures (3-zonocolpate, 3-zonocolp-porate) as well as six morphological types of pollen based on three main types of exine ornamentation (tuberculate, verrucate, rugulate). We suggest that two main groups of exine ornamentation developed from a common initial type. The first group covers all species of the subgenus Quercus and also Q. suber and Q. alnifolia of the subgenus Heterobalanus. The second group is limited to the morphological type Q. ilex (species Q. ilex, Q. coccifera, subgenus Heterobalanus). On the other hand, the presence of widespread interspecific and introgressive hybridization within the genus Quercus indicates an ongoing process of speciation. This also has an effect on pollen features, which are very similar in a number of species but also vary in individual samples even within the same species. The morphological uniformity of the pollen surface (especially for the subgenus Quercus), the presence of islets of secondary sporopollenin on the surface of pollen grains, as well as orbicules in anthers, do not indicate general primitiveness of representatives of this genus but most likely denote a relatively high degree of speciation activity within this group.

CYTOLOGY OF POPLAR SPECIES AND NATURAL HYBRIDS

1938 ◽  
Vol 16c (11) ◽  
pp. 445-455 ◽  
Author(s):  
F. H. Peto
Keyword(s):  
Size Distribution ◽  
Genetic Factors ◽  
Chromosome Complement ◽  
Pollen Grains ◽  
Pollen Size ◽  
Cell Nuclei ◽  
Good Pollen ◽  
Natural Hybrids ◽  
Pollen Diameter ◽  
High Degree

Complete analyses of pollen-mother-cell nuclei at first metaphase, percentage good pollen, pollen diameter and pollen-size distribution were determired for the following poplar species and natural hybrids: Populus grandidentata Michx., P. tremuloides Michx., P. eugenei Simon Louis, P. alba L., P. canescens Sm., natural hybrids of P. alba × P. grandidentata and of P. alba × P. tremuloides.Both of the P. alba and two of the four P. canescens trees examined were triploids (2n = 57) while all other trees examined were diploids (2n = 38). Meiotic observations on the natural hybrids indicated a high degree of homology between the chromosomes of P. alba and the native aspens (P. grandidentata and P. tremuloides), since 17 to 19 bivalents were usually found at first metaphase. In collections from one triploid P. canescens and two diploid alba-grandidentata hybrid trees, failure of a high proportion of the chromosomes to pair was attributed to genetic factors limiting pairing, rather than to non-homology.Pollen characters such as percentage good pollen, pollen diameter, and pollen size distribution were, in most cases, not indicative of the chromosome number or pairing relations at first metaphase. Consequently, triploids could not be detected by pollen observations under the conditions of this experiment. In spite of the lack of correlation between first metaphase and pollen observations, abnormally large pollen grains were observed in collections from several of the trees, and these were considered to contain the diploid or unreduced chromosome complement. The tendency for the poplars to produce unreduced pollen grains probably accounts for the number of triploid trees discovered in Canada and Sweden.

Comparative morphological, anatomical, micromorphological, and palynological studies on the genera Opopanax and Crenosciadium (Apiaceae)

Phytotaxa ◽  
2018 ◽  
Vol 372 (1) ◽  
pp. 35 ◽  
Author(s):  
ÖZLEM ÇETIN ◽  
MUSTAFA ÇELIK
Keyword(s):  
Cross Sections ◽  
Mediterranean Region ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Molecular Data ◽  
Monotypic Genus ◽  
Western Asia ◽  
The Family ◽  
Surface Ornamentation ◽  
Fruit Surface

In the present study, morphological, micromorphological, palynological and anatomical characteristics of the genera Opopanax and Crenosciadium are reviewed and compared. The genus Opopanax is distributed in southern Europe, the Mediterranean region and Western Asia, and it is represented by three species in Turkey. Crenosciadium is a poorly known monotypic genus from Turkey, recently treated as synonym in Opopanax. Expanded descriptions, phenology, geographic distributions, and images of habitus of Opopanax and Crenosciadium are given. The differences between the two genera are discussed. The pollen morphology of Opopanax and Crenosciadium is studied by SEM and LM. The palynological results confirmed the stenopalynous characteristic of the family Apiaceae, and revealed that the pollen grains of both genera are perprolate in shape. Also fruit surface ornamentation of both genera is typically striate, and epidermal cells are polygonal or elongated in one direction. Cross-sections of mature fruits are examined and a detailed anatomical description is presented. Mericarp shape and width are very useful characters for discrimination between Opopanax and Crenosciadium; mericarp ribs are also very significant characteristics to discriminate both genera. Our findings, together with previous molecular data, clearly indicate that Crenosciadium differs considerably from Opopanax, and therefore it should be accepted at genus rank.

scholarly journals Pollen characters as taxonomic evidence in some species of Dipsacaceae from Iran

2017 ◽  
Vol 24 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Ebadi-Nahari Mostafa ◽  
Nikzat-Siahkolaee Sedigheh ◽  
Eftekharian Rosa
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Pollen Type ◽  
Upgma Tree ◽  
Pollen Characters ◽  
Exine Ornamentation ◽  
The Family ◽  
The World ◽  
Plant Taxon

Pollen morphology of nine species representing four genera: Cephalaria Schrad, Dipsacus L., Pterocephalus Vaill. and Scabiosa L. of the family Dipsacaceae in Iran has been investigated by means of scanning electron microscopy (SEM). The results showed that pollen grains were triporate and tricolpate. The pollen type of Scabiosa rotata Bieb. (tri- and tetraporate) is the first report in the world. The sizes of pollen grains fall into the classification group magna (pollen grain diameter 50–100 μm). Pollen shapes vary from preoblate to prolate and their polar views were triangulate and lobate. The exine ornamentation varies from gemmate in S. rotata to spinulate in the rest studied species. Species of Scabiosa have been dispersed in UPGMA tree that this confirmed the previous studies about taxonomic problems and species complexity in this genus. These results show the transfer of the some Scabisoa species to Lomelosia Raf. based on palynological characters. Pollen morphology of the family is helpful at the generic and specific level.Bangladesh J. Plant Taxon. 24(2): 129–136, 2017 (December)

scholarly journals Pollen morphology of Iranian Dracocephalum L. (Lamiaceae) and its taxonomic significance

2015 ◽  
Vol 22 (2) ◽  
pp. 99-110 ◽  
Author(s):  
Maryam Naderifar ◽  
Ali Sonboli ◽  
Abbas Gholipour
Keyword(s):  
Electron Microscopy ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Polar View ◽  
Taxonomic Significance ◽  
Infrageneric Classification ◽  
Exine Ornamentation ◽  
Plant Taxon ◽  
Scanning Electron

Pollen morphology of 11 Iranian Dracocephalum L. species was investigated using light and scanning electron microscopy to evaluate their taxonomic significance for the infrageneric classification of the genus. Pollen grains of all examined taxa were isopolar, hexacolpate, circular in polar view and spheroidal to prolate in equatorial view (P/E = 1.0?2.0). The smallest pollen grains were observed in D. aucheri (P = 29.7 ?m, E = 22.6 ?m), while the largest pollen was found in D. lindbergii (P = 45.1 ?m, E = 33.7 ?m). The highest and lowest apocolpium index (AI) were measured in D. aucheri (AI = 0.27) and D. surmandinum (AI = 0.08), respectively. Colpus membrane was egranulate in all examined species except for D. multicaule and D. ghahremanii. The main exine ornamentation type was characterized as bireticulate including five different subtypes. The results revealed that the exine ornamentation is a diagnostic character useful for the classification of Dracocephalum.Bangladesh J. Plant Taxon. 22(2): 99-110, 2015 (December)

scholarly journals Relationship between pollen morphology and chromosome numbers in Brazilian species of Lippia L. (Verbenaceae)

2013 ◽  
Vol 85 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Saulo M. Sousa ◽  
Patrícia M.O. Pierre ◽  
Giovana A. Torres ◽  
Lisete C. Davide ◽  
Lyderson F. Viccini
Keyword(s):  
Chromosome Numbers ◽  
Pollen Morphology ◽  
Pollen Grains ◽  
Positive Association ◽  
Single Species ◽  
Morphological Data ◽  
Prolate Spheroidal ◽  
Oblate Spheroidal ◽  
Exine Ornamentation ◽  
Different Types

The pollen morphology and exine structure of 17 species of Lippia L. were investigated in this work using light and scanning electron microscopy. Among the species studied, 14 showed tricolporate pollen grains, two had tri- and tetracolporate pollen grains and a single species exhibited, only tetracolporate pollen. The amb ranged from triangular to square, and the shape varied from oblate-spheroidal to prolate-spheroidal. Three different types of exine ornamentation were observed: psilate, scabrate and perforate. In addition to morphological data, we found positive association between the chromosome numbers and size of pollen grains, and also between the length and width of the colpi. The results indicate that the characteristics of pollen grains in Lippia may be used as an additional taxonomic character of the genus.

Taxonomic studies in the genus Haplanthodes (Acanthaceae)

Phytotaxa ◽  
2021 ◽  
Vol 516 (3) ◽  
Author(s):  
PRADIP VIKRAM DESHMUKH ◽  
SIDDHARTHAN SURVESWARAN ◽  
RAMCHANDRA DNYANOBA GORE ◽  
MANOJ MADHWANAND LEKHAK
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscope ◽  
Pollen Grains ◽  
Prolate Spheroidal ◽  
New Variety ◽  
Exine Ornamentation ◽  
Taxonomic Studies ◽  
First Time ◽  
Scanning Electron

The endemic Indian genus Haplanthodes (Acanthaceae) is revised. Four species, viz. H. neilgherryensis, H. plumosa, H. tentaculata and H. verticillata and a new variety, H. neilgherryensis var. toranganensis are recognized. Lectotype is designated for Haplanthodes, Haplanthus plumosus and H. verticillaris. The nomenclature of the Linnaean name Ruellia tentaculata is also discussed. Micromorphology of seed using light microscope (LM) and scanning electron microscope (SEM) is observed for the first time, and two types, reticulate and micro papillate, have been recognized based on surface sculpturing pattern. The genus differs from the related genera Andrographis and Haplanthus by distinctly two grooved seeds with hygroscopic hairs. Pollen grains of the genus are oblate or prolate spheroidal, distinctly triangular, trizonocolporate with reticulate exine ornamentation.

scholarly journals Ancient DNA shows domestic horses were introduced in the southern Caucasus and Anatolia during the Bronze Age

2020 ◽  
Vol 6 (38) ◽  
pp. eabb0030
Author(s):  
Silvia Guimaraes ◽  
Benjamin S. Arbuckle ◽  
Joris Peters ◽  
Sarah E. Adcock ◽  
Hijlke Buitenhuis ◽  
...  
Keyword(s):  
Bronze Age ◽  
Iron Age ◽  
Large Scale ◽  
Early Neolithic ◽  
The Caucasus ◽  
Domestic Horses ◽  
Third Millennium Bce ◽  
History Of ◽  
Southern Caucasus ◽  
The Bronze Age

Despite the important roles that horses have played in human history, particularly in the spread of languages and cultures, and correspondingly intensive research on this topic, the origin of domestic horses remains elusive. Several domestication centers have been hypothesized, but most of these have been invalidated through recent paleogenetic studies. Anatolia is a region with an extended history of horse exploitation that has been considered a candidate for the origins of domestic horses but has never been subject to detailed investigation. Our paleogenetic study of pre- and protohistoric horses in Anatolia and the Caucasus, based on a diachronic sample from the early Neolithic to the Iron Age (~8000 to ~1000 BCE) that encompasses the presumed transition from wild to domestic horses (4000 to 3000 BCE), shows the rapid and large-scale introduction of domestic horses at the end of the third millennium BCE. Thus, our results argue strongly against autochthonous independent domestication of horses in Anatolia.

scholarly journals SERS activity of hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
R. D. Ávila-Avilés ◽  
N. Torres-Gómez ◽  
M. A. Camacho-López ◽  
A. R. Vilchis-Nestor
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Pollen Grains ◽  
Precipitation Method ◽  
Chemical Composition Distribution ◽  
Transmission Electron ◽  
Pollen Surface ◽  
Surface Enhanced Raman ◽  
Enhanced Raman Scattering ◽  
Co Precipitation

Abstract Nature provides remarkable examples of mass-produced microscale particles with structures and chemistries optimized by evolution for particular functions. Synthetic chemical tailoring of such sustainable biogenic particles may be used to generate new multifunctional materials. Herein, we report a facile method for the synthesis of hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template. Silver nanoparticles was biosynthesized using pollen grains as a reduction and stabilization agent as well as a bio-template promoting the adhesion of silver nanoparticles to pollen surface. Fe3O4 nanoparticles were synthesized by co-precipitation method from FeSO4. Hybrid nano/microstructures Ag-Fe3O4 based on Dimorphotheca ecklonis pollen grains as bio-template were obtained and characterized using Scanning Electron Microscopy and Transmission Electron Microscopy to study the morphology and structure; Energy-Dispersive X-ray Spectroscopy to determine the chemical composition distribution; and Confocal Fluorescence Microscopy to demonstrate the fluorescence properties of hybrid nano-microstructures. Furthermore, these hybrid nano-microstructures have been studied by Surface-Enhanced Raman Scattering (SERS), using methylene blue as a target molecule; the hybrid nano-microstructures have shown 14 times signal amplification.

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