Observations on the variation in pollen morphology of Palmae and its significance

1986 ◽  
Vol 64 (12) ◽  
pp. 3079-3090 ◽  
Author(s):  
I. K. Ferguson

Study of the pollen morphology of the Palmae by using scanning electron microscopy and transmission electron microscopy shows that there is more remarkable variation and parallelism in pollen characters, especially exine ornamentation and stratification, than has been demonstrated previously. The pollen of Arenga borneensis has gemmate exine ornamentation and closely resembles that of species of the closely related Caryota (Caryoteae) as well as Iriartea and Dictyocaryum (Iriarteae). Some species of Pinanga (Areceae), Korthalsia, and Daemonorops (Calameae) have pollen which can only be separated from the A. borneensis type by careful electron microscope study. Other species of Arenga have spiny pollen with a smooth foot layer, which resemble Wallichia (Caryoteae) and other Caryota species. Catoblastus, Wettinia, and Socratea (Iriarteae) have similar characteristic pollen with columellate spines interspersed with dense scabrate ornamentation. Again, species of Pinanga and Korthalsia have superficially similar pollen, as do the genera Mauritia, Mauritiella, and Lepidocaryum (Lepidocaryeae). However, these groups can be distinguished by structural differences of the spines. Very similar tectate, perforate pollen with supratectal spines occur in genera which have small differences in apertures but are widely separated taxonomically. These include Pinanga, Nypa, Salacca (Calameae), and Ravenea (Ceroxyleae). In view of this variation and parallelism it is suggested that there is a need for caution in assigning fossil pollen to extant genera until a much more detailed and extensive study of palm pollen morphology is carried out.

Author(s):  
Mehdi Heidarian ◽  
Seyed Mohammad Mehdi Hamdi ◽  
Mohammad Mehdi Dehshiri ◽  
Taher Nejadsattari ◽  
Seyed Mohammad Masoumi

Aims: The aim of this research was to investigate the morphological characteristics of the pollen grain of some species of genus Allium. Methodology: The pollen grains were examined by using Light Microscopy (LM), Scanning Electron Microscopy (SEM) and the pollen grains of one species under Transmission Electron Microscopy (TEM). Results: The pollen grains were oblate and medium in shape and size. The pollen ornamentation of exine surface, exine ornamentation on sulcus edge, lumina number in the exine surface and the state of pollen grain apex in the examined species were different. Semitectate and columellate ectexine with discontinuous endexine were seen in the pollen wall structure (sporoderm). The dendrogram obtained from the pollen characters in SEM observations by using the numerical taxonomy system (NTSYS) software placed the studied species in two types. Conclusion: Our palynological dendrogram can be used for segregation the sections and subgenera taxonomical levels in the studied species of genus Allium and confirmed the phylogram of the recent phylogenetic research.


Biologia ◽  
2006 ◽  
Vol 61 (4) ◽  
Author(s):  
Ümmügülsüm Güler ◽  
Sevil Pehlivan

AbstractPollen morphology of 14 Allium L. species grown in Turkey, that belong to the sections Codonoprasum and Allium, were investigated under LM (light microscopy) and by SEM (scanning electron microscopy). However, the pollens of 5 species were investigated under TEM (transmission electron microscopy). Detailed pollen morphological characteristics are given for Allium in the family on the basis of the results presented here together with data from the literature. The genera Allium homogeneous in both aperture type and exine ornamentation. It is suggested that some palynological characters, such as aperture type and the presence of an operculum, could be of taxonomic value at the section level.


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)


Phytotaxa ◽  
2015 ◽  
Vol 207 (1) ◽  
pp. 135 ◽  
Author(s):  
Giovanni Raul Bogota ◽  
Carina Hoorn ◽  
Wim Star ◽  
Rob Langelaan ◽  
Hannah Banks ◽  
...  

Sabinaria magnifica is so far the only known species in the recently discovered tropical palm genus Sabinaria (Arecaceae). Here we present a complete description of the pollen morphology of this palm species based on light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We also made SEM-based comparisons of Sabinaria with other genera within the tribe Cryosophileae. Pollen grains of Sabinaria magnifica resemble the other genera in the heteropolar, slightly asymmetric monads, and the monosulcate and tectate exine with perforate surface. Nevertheless, there are some clear differences with Thrinax, Chelyocarpus and Cryosophila in terms of aperture and exine. S. magnifica differs from its closest relative, Itaya amicorum, in the exine structure. This study shows that a combination of microscope techniques is essential for the identification of different genera within the Cryosophileae and may also be a necessary when working with other palynologically less distinct palm genera. 


2012 ◽  
Vol 19 (2) ◽  
pp. 191-200 ◽  
Author(s):  
Sangeeta Rajbhandary ◽  
Mark Hughes ◽  
Krishna K. Shrestha

The pollen morphology of 28 Begonia species of Nepal has been examined by scanning electron microscopy (SEM). Comparative pollen analysis was made based on size, shape in polar and equatorial views, P/E ratio, aperture, and exine ornamentation. In this study, four types of pollen ornamentation morphology have been identified. Among Nepalese Begonia, B. roxburghii (section Sphenanthera) has the smallest pollen (11.2- 12.8 × 6.4-7.0 ?m) and B. flagellaris (section Diploclinium) has the largest pollen (24.3- 30.6 × 11.4-12.0 ?m). Presence of margo in the pollen ornamentation is a distinguishing character that separates Begonia section Platycentrum from all other sections of Nepalese Begonia. DOI: http://dx.doi.org/10.3329/bjpt.v19i2.13134 Bangladesh J. Plant Taxon. 19(2): 191-200, 2012 (December)


Genetika ◽  
2020 ◽  
Vol 52 (1) ◽  
pp. 187-198 ◽  
Author(s):  
Dragan Nikolic ◽  
Dragan Milatovic ◽  
Aleksandar Radovic ◽  
Jugoslav Trajkovic

Morphology and ultrastructure of pollen grains were studied in 13 Obla?inska sour cherry clones in three years using scanning electron microscopy (SEM). All studied clones had isopolar, radially symmetric and tricolpate pollen grains. Length and width of pollen grains varied in a range of 50.03-55.97 ?m and 25.16-28.37 ?m respectively. Pollen shape in all the studied clones was identified as prolate. The smallest colpus length was found in the clone 8 (43.73 ?m), and the highest in the clone 3 (49.16 ?m). The highest colpus and mesocolpium width had the clone 3 (1.73 ?m; 14.87 ?m) and the lowest had the clone 7 (1.46 ?m; 13.78 ?m). All studied clones had striate exine ornamentation. Number of ridges per 100 ?m2 of the exine surface was the highest in the clone 11 (16.7) and lowest in the clone 2 (14.1). Ridge and furrow width ranged from 0.46 to 0.61 ?m and from 0.45 to 0.59 ?m, respectively. The clones have been classified into three clusters based on all studied properties. Pollen grains examination by SEM indicated that several morphological parameters (pollen size and exine characteristics) can be used to distinguish Obla?inska sour cherry clones.


2013 ◽  
Vol 26 (6) ◽  
pp. 393
Author(s):  
Carol A. Furness ◽  
John G. Conran ◽  
Thomas Gregory ◽  
Paula J. Rudall

We examined pollen of 19 genera of Hemerocallidaceae by using scanning electron microscopy (SEM), and one genus (Dianella) by using transmission electron microscopy (TEM). Pollen was generally small in size, with a rounded triangular outline when hydrated, and a characteristic three-armed aperture, a distal trichotomosulcus. The pollen surface was finely sculptured and the exine was thin. Microreticulate pollen is a potential synapomorphy for several species of the ‘crown phormioid’ subclade recognised in molecular analyses. Perforate and fossulate pollen supports a relationship between several species of Dianella. Microrugulate pollen is more frequent in the johnsonioids than in the phormioids. Hemerocallis is distinguished by elongated monosulcate pollen, a relatively thick exine with a pronounced reticulate surface, and large globules of attached pollenkitt. We hypothesise that Hemerocallidaceae are ancestrally buzz-pollinated, and their pollen morphology is an adaptation to this pollination type. A reversal to butterfly or moth pollination occurred in Hemerocallis, with associated changes in pollen morphology.


Phytotaxa ◽  
2018 ◽  
Vol 371 (3) ◽  
pp. 145 ◽  
Author(s):  
TUNCAY DİRMENCİ ◽  
TANER ÖZCAN ◽  
TÜRKER YAZICI ◽  
TURAN ARABACI ◽  
ESRA MARTİN

Two new hybrids of Origanum, O. ×malyeri and O. ×sevcaniae, are described and illustrated in detail. The general morphology, pollen and chromosome features, and nuclear (ITS) and chloroplast (rpl32) genomes of collected specimens were studied. Origanum ×malyeri is a hybrid between O. boissieri and O. vulgare subsp. hirtum and O. ×sevcaniae is another hybrid between O. vulgare subsp. hirtum and O. vogelii. These two new hybrids have some morphological intermediate characters between their parents. The pollen morphology of O. ×sevcaniae and its parents were studied and documented in detail using light microscopy (LM) and scanning electron microscopy (SEM). O. ×sevcaniae pollen is small to medium (P=18.49–21.03 µm, E=22.20–26.63 µm), suboblate (73%) to oblate (22%), the range of P/E ratio is from 0.73 to 0.85. Pollen grains are hexacolpate with granular membranes. Pollen grains were identified as bireticulate exine ornamentation with scanning electron microscopy examinations. The somatic chromosome number of O. boissieri, O. vulgare subsp. hirtum, O. vogelii, and O. ×sevcaniae were counted as 2n = 30. Pollen characters and somatic chromosome numbers of O. ×malyeri could not be examined because it has only female flowers and has not any nutlets. Also, according to molecular results, O. ×malyeri and O. ×sevcaniae have some polymorphic nucleotide regions in their nuclear ITS genomes and which means they have two different DNA dataset belonging to their parents. Also, some individuals of O. ×sevcaniae parents have single nucleotide polymorphism, too. These individuals live together with their hybrids and hybridization is probably a continuing process in that hybrid swarms. These present results support previous reports for the speciation of Origanum members via hybridization.


1978 ◽  
Vol 56 (22) ◽  
pp. 2853-2864 ◽  
Author(s):  
Sylvia Feuer ◽  
Job Kuijt

An examination of pollen morphology and ultrastructure of Eremolepidaceae (Antidaphne, Ixidium, Eremolepis, Eubrachion) and Lepidoceras by light and scanning and transmission electron microscopy reveals a close relationship among the taxa. Pollen of Eremolepidaceae is typically echinate, tricolporate, and oblate-spheroidal. Eubrachion is unique within the family, exhibiting shallowly reticulate pollen. Ultrastructurally, all Eremolepidaceae exhibit a similar exine structure. The sculptural ektexinous elements (spines or 'muri') are never contiguous with the basal ektexine but rest on a thin granular zone. Pollen characters of Lepidoceras are particularly close to those of Ixidium and Eremolepis. The porate (por(or)ate) aperture type, completely spherical shape, and reduced granular ektexine of Lepidoceras pollen indicate an advanced position within the complex. The relationship of Tupeia to Eremolepidaceae is more obscure as pollen of the genus exhibits both eremolepidaceous (echinate sculpturing, shape in polar and equatorial views) as well as loranthaceous characters (simple apertures, ektexine organization). Palynologically Eremolepidaceae and related genera show no particular close relationship to Olacaceae or Santalaceae. Though Eremolepidaceae et al. do share a number of pollen features with Viscaceae (echinate sculpturing, compound apertures, exine organization) the strong nonpalynological differences between the two families suggest that these pollen features may have arisen independently.


2019 ◽  
Vol 26 (1) ◽  
pp. 47-55
Author(s):  
Birol Başer ◽  
Mehmet Firat ◽  
Riza Binzet

The pollen morphology of 10 Allium L. taxa, 6 of which are endemic to Turkey, were investigated in detail by light and scanning electron microscopy. According to LM and SEM, the pollen grains of genera were monad, monosulcate percolate, heteropolar with bilateral symmetry, 25.30 to 53,85 µm long axis (LA) and 17.55 to 36.86 µm short axis (SA), the form was prolate (mean of LA/SA ratio 1.30 to 1.70 and in polar view boat-shaped. Three types of ornamentation were determined. Striate-rugulate-perforate type in Allium longisepalum, A. oreophilum, A. anacoleum, A. microspathum, A.shirnakiense, A. purpureoviride and A. armenum, Rugulate–perforate type in A. pervariense and A. gabardagense and Rugulate–reticulate-perforate type in A. arlgirdense. Sulcus membrane ornamentations were rugulate or psilate. The sulcus extends from the distal to proximal ends in A. anacoleum, A. arlgirdense and A. pervariense. The present study on some Turkish species of Allium showed that several morphological pollen characters may possess taxonomical value.


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