Pollen morphology of the Rosaceae of western Canada. IV. Luetkea, Oemleria, Physocarpus, Prunus

1991 ◽  
Vol 69 (12) ◽  
pp. 2583-2596 ◽  
Author(s):  
R. J. Hebda ◽  
C. C. Chinnappa ◽  
B. M. Smith

Pollen grains of 12 species of western Canadian rosaceous genera, Luetkea, Oemleria, Physocarpus, and Prunus, were studied in the light microscope and scanning electron microscope. All pollen grains are produced as isopolar, radially symmetrical, usually tricolporate monads. Grains are predominantly spheroidal with a circular to triangular amb. Most of the species exhibit a well-developed chambered aperture complex at the equator, formed by a pair of sexinal flaps whereas in Prunus spinosa, Prunus americana, and Prunus virginiana the chamber is absent or weakly developed. Oemleria cerasiformis has no pore flaps. Apertures of Prunus emarginata and Prunus virginiana often have an equatorial bridge over the aperture complex. The exine of Prunus, Physocarpus, and Luetkea pollen is tectate perforate, like that of many Rosaceae. Sculpturing consists of ridges and valleys that form a striate to rugulate pattern. Ridges and valleys tend to be mainly parallel to the colpus but often loop near the poles. Pollen grains of Prunus spinosa are always rugulate or vermiculate with ridges arranged randomly. Oemleria cerasiformis pollen appears tectate imperforate. Ridges and valleys intersect at triple points in the subpolar region and curve in a semicircle around the pore area. On this basis Oemleria pollen is distinct from all other western Canadian Rosaceae. Pollen grain size ranges from small for Luetkea pectinata (17 μm in diameter) to medium for Prunus spinosa (36 × 33 μm). Key words: pollen morphology, Rosaceae, Western Canada, systematics.

2017 ◽  
Vol 59 (2) ◽  
pp. 63-75 ◽  
Author(s):  
Małgorzata Klimko ◽  
Renata Nowińska ◽  
Paul Wilkin ◽  
Justyna Wiland-Szymańska

AbstractPollen grains of 15 species of the genus Sansevieria were examined using light and scanning electron microscopy. The pollen grains were single, but dyads were also found. The basic shape of the pollen grains (with chemical treatment) was subprolate, prolate and prolate-spheroidal and the pollen grains were large (> 50 mm). The pollen grains observed in SEM were prolate-spheroidal, subprolate, prolate and perprolate. The aperture occupied nearly the entire distal hemisphere. The surface of non-apertural areas was microreticulate, psilate-perforate, fossulate and verrucate. The surface of the apertural area was psilate-perforate-verrucate, microreticulate-verrucategemmate and psilate-perforate. The tectum was homogeneous, with perforations. Our results suggest that some species cannot be separated based on pollen grain morphology, but only may be categorized into their groups. The present study investigated pollen grain morphology in eleven species for the first time in terms of pollen micromorphology and provided some important new data.


2011 ◽  
Vol 73 (4) ◽  
pp. 315-325 ◽  
Author(s):  
Małgorzata Klimko ◽  
Krystyna Idzikowska ◽  
Mariola Truchan ◽  
Anna Kreft

Pollen grains of 9 species of the genus <em>Plantago</em> (Plantaginaceae), including 8 taxa native to Poland, were observed under a light microscope and a scanning electron microscope. Descriptions of grain sculpture are illustrated only SEM micrographs. The studied pollen grains were medium-sized or small, spherical or prolate spheroidal. Their sculpture was always verrucate with granulation. In the studied taxa, internal apertures had the form of pores. Their number ranged from (4)5-9(14). The pores were scattered on the surface of pollen grains. Identification features of individual taxa include: presence or absence of an annulus around each pore, annulus structure, ornamentation of the pollen grain and operculum, type of aperture membrane, number of internal pores, and pore diameter. We suggest that two new pollen grain types, characteristic of <em>P. intermedia</em> and <em>P. arenaria</em>, should be distinguished, and that <em>P. alpina</em> should be assigned to the <em>P. coronopus</em> type.


2011 ◽  
Vol 79 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Mahnaz Vafadar ◽  
Farideh Attar ◽  
Hosein Maroofi ◽  
Mansur Mirtadzadini

Pollen grain of 16 species and three hybrids of the genus <em>Amygdalus</em> L., representing two subgenera and two sections distributed in Iran were examined by light and scanning electron microscopy. All pollen grains are tricolporate. The shape of grains varies from subprolate through prolate. Regarding outline, in polar view, pollen grains are triangular-circular and in equatorial view, elliptic. Regarding sculpturing of exine, the frequent type like many members of family <em>Rosaceae</em> is striate with or without perforations that can be subdivided into three subtypes: type I (A-B), type II (A-B) and type V. In three species, <em>A. trichamygdalus</em>, <em>A. spinosissima</em> and <em>A. orientalis</em>, exine sculpture type is completely different. In the first species is rugulate, in the second species is reticulate and in <em>A. orientalis</em>, it is gemmate-perforate. Ornamentation of ridges (muri) in the striate sculpture is parallel to ectocolpus. Number of perforations in tectum, diameter of them, striae intervals and the thickness of ridges varies among studied taxa. The striae have different depth and slope. Results showed that among pollen grain characters, shape is useful character solely for separating of taxonomic ranks in Iranian Amygdalus specially in subgeneric or section level.


Genetika ◽  
2021 ◽  
Vol 53 (2) ◽  
pp. 851-865
Author(s):  
Fahimeh Fallah ◽  
Farrokh Ghahremaninejad

The palynomorphological characteristics of 5 species belonging to Hedera of the Araliaceae family were studied in detail. These plant species were collected from various phytogeographical regions of Iran and Hungary. The palynological investigation was accomplished using Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM). Pollen grains of the species are reticulate, prolate, sub-prolate, tricolporate, isopolar, radially symmetrical, and monad. The largest pollen grain was in the Hedera colchica species (72.24?1.6 ?m) and the smallest pollen grain was in Hedera helix (28.63?2.1 ?m). The research carried out by the TEM showed that the species were different in terms of exine thickness, tectum thickness, foot layer thickness, the diameter and length of the Columella, the thickness and shape of the Caput, the tectum to foot layer )T/F( ratio, the absence or presence of the Endexine and the thickness of the Intine layers. The main purpose of this study was the importance of the relationship between pollen grain size and the number of chromosomes and ploidy level in Hedera species.


1988 ◽  
Vol 66 (4) ◽  
pp. 595-612 ◽  
Author(s):  
R. J. Hebda ◽  
C. C. Chinnappa ◽  
B. M. Smith

Morphology and geographic variation of pollen grains of three genera of the Rosaceae (Dryas, Fragaria, Holodiscus) of western Canada were studied using the light microscope and scanning electron microscope. Dryas spp. pollen is tricolporate with a weakly developed fusiform aperture in the colpus, which upon expansion of the grain becomes a large rectangular opening. Sculpturing consists of ridges and valleys (striate or rugulate), the latter containing perforations, which grades to a network of ridges and perforations (reticulate) at colpus margins. Ridges are parallel to the colpus or form looping patterns. Dryas integrifolia and Dryas octopetala pollen in silicone oil usually are larger than those of Dryas drummondii. Fragaria spp. pollen is tricolporate with a well-developed complex equatorial aperture. Fragaria chiloensis and F. vesca exhibit a lobed and equatorially extended endoaperture, which is overarched by sexine. Fragaria virginiana usually has a less distinct endoaperture. Fragaria species have a fusiform colpus operculum. Sculpturing consists of nonasastomosing ridges parallel to the colpus and valleys containing obscure microperforations. Holodiscus discolor pollen is tricolporate. Sculpturing is striate to reticulostriate, consisting of ridges and valleys with perforations. A distinct zone, either lacking ridges or of densely packed ridges, borders the colpus.


2015 ◽  
Vol 57 (1) ◽  
pp. 149-160 ◽  
Author(s):  
Joanna Bykowska ◽  
Małgorzata Klimko

Abstract Pollen grains of Pinus mugo, P. sylvestris and P. ×rhaetica (= P. mugo × P. sylvestris) were examined by light and scanning electron microscopy. The pollen grains were bisaccate and monosulcate. The corpus-saccus attachment was distinct. The pollen corpus exine sculpture was verrucate-rugulate and deeply sculptured. The surface of the tectum was covered with small grana and it was perforate. The saccus sexine ornamentation was reticulate and irregularly perforate. The tectum surface characters in the proximal and distal view of the corpus and saccus were less variable and they did not provide good criteria to identify the species under study. However, some differences were observed in the size of elevation on the corpus between pollen grains of the same species and between the parental species. This study of the pollen grain morphology of the corpus and saccus provided some important new data.


1990 ◽  
Vol 68 (6) ◽  
pp. 1369-1378 ◽  
Author(s):  
R. J. Hebda ◽  
C. C. Chinnappa

Pollen grains of eight species of Geum (Rosaceae) from western Canada were studied in the light microscope and the scanning electron microscope. The taxa included Geum aleppicum, Geum calthifolium, Geum glaciale, Geum macrophyllum, Geum rivale, Geum rossii, Geum schofieldii, and Geum triflorum. All taxa produce pollen grains in monads that are isopolar, radially symmetrical, and predominantly tricolporate. Tetracolporate grains occur especially in Geum rossii and Geum calthifolium. Grains are subspheroidal to subprolate with a circular to subtriangular amb. All taxa exhibit a well-developed chambered aperture formed by overarching pore flaps. Flaps extend over the aperture but do not join to form an equatorial bridge. The chamber of Geum schofieldii is distinct and complex, often extending equatorially along a sinuous path to the adjacent aperture. Exine is tectate, microperforate, with a thin nexine. Sculpturing is striate or occasionally rugulate and consists of ridges and valleys with microperforations on valley floors. Ridges and valleys are oriented predominantly parallel to the colpus but occasionally curve or loop near the poles. Sculpturing of Geum schofieldii pollen, is predominantly striate but exhibits a unique verrucate to rugulate pattern along the equator caused by elaboration of the sexine. Polar diameter varies from ca. 20 μm in Geum macrophyllum to 33 μm in Geum schofieldii. The distinctness of Geum schofieldii pollen supports specific status.


2014 ◽  
Vol 65 (1-2) ◽  
pp. 111-116 ◽  
Author(s):  
Renata Śnieżko

Flowers of <em>Oenothera hookeri</em> Torr. et Gray, <em>Oe. brevistylis</em> and <em>Oe. lamarkiana</em> de Vries were pollinated after anthesis by insects. <em>Oe. biennis</em> L., <em>Oe. suaveolens</em> Desf and sulfurea were selfpollinated in the buds. Pollen morphology was slightly different: <em>Oe. hookeri</em> have regular, triporated pollen, often germinating through two pores; in <em>Oe. suaveolens</em> many pollen grains had callose patches on the intine; in <em>Oe. brevistylis</em> tetraporated pollen were more often than in other species; in <em>Oe. lamarckiana</em> many pollen grains were empty; in <em>Oe. biennis</em> and <em>Oe. suaveolens</em> pollen grain size and viability varied. The pollen tube growth and fertilization were similar in 5 species and can be considered as typical for <em>Oenothera</em>. In the ovary pollen tubes branched and changed their growth direction. Near micropyle they formed short branches to the inner integument. In the nucellus the pollen tube became swollen.


2017 ◽  
Vol 24 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Ebadi-Nahari Mostafa ◽  
Nikzat-Siahkolaee Sedigheh ◽  
Eftekharian Rosa

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)


2015 ◽  
Vol 22 (2) ◽  
pp. 99-110 ◽  
Author(s):  
Maryam Naderifar ◽  
Ali Sonboli ◽  
Abbas Gholipour

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)


Sign in / Sign up

Export Citation Format

Share Document