© TÜBİTAK Contributions to the Pollen morphology of the family Compositae (original) (raw)

Contributions to the pollen morphology of the family Compositae

1999

The pollen morphology of 24 species of Compositae belonging to 18 genera was examined by light and scanning microscopy. The present data confirms the eurypalynous nature of the family. Delimitation of the genera on the basis of pollen characters is less marked. Pollen grains usually radially symmetrical, isopolar rarely apolar; tricolporate, often porate. Shape commonly oblatespheroidal to prolate-spheroidal, with some suboblate to subprolate types. Tectum echinate to echinolophate, often non-echinate. Tectum in-between the spines or spinules is sub-psilate, or perforated to striate. On the basis of the exine pattern, 4 distinct pollen types are recognized viz., Pollen type-I: Dicoma tomentosa, Pollen type-II: Eclipta prostrata, Pollen type-III: Echinops echinatus and Pollen type-IV: Launaea nudicaulis. Within the pollen types, pollen characters are significantly sufficient for characterization of the species. An interesting correlation observed is that the taxa having spiny capitula have a mostly non-echinate or spinulose tectum with very thick exine (7-25 µm).

Studies on pollen morphology ofRosaceae

Acta Botanica Gallica, 1994

Light and scanning electron microscope studies of pollen representing geo1era from all tribes of the Rosaceae reveal a variety of form and sculpturing. All genera examined produce radially symmetric isopolar monads. Most genera in subfamilies Maloideae, Prunoideae, and Sp/raeoideae produce tricolporate striate grains with large perforations in valleys between ridges. These tectate perforate grains have a chambered pore covered by arching ektexinal pore flaps. The ridge-and-valley pattern can vary from t-long ridges parallel to the colpus, to 2-medium to long ridges looping near the poles, to 3 • short weaving and crossing ridges. Striate perforate pollen occurs in tribes Dryadeae, Kerrieae, Roseae (operculate) and Rubeae of subfamily Rosoideae. in some Rubus species perforate and verrucate sculpturing occurs. Tribe Potentilleae (= Fragarieae) produces pollen with microperforations rather than typical perforations and most genera have an operculum. Coluria. Fallugia, Geum, Orthurus, and Wa/dsteinia of Dryadeae produce striate microperforate pollen, suggesting that they may belong in the Potentilleae. Filipendula (Uimarieae) is prominently verrucate. Tuberculate perforate sculpturing occurs in Cercocarpus, Cowan/a, and Purshia suggesting a natural group distinct frcm the rest of the family. The diverse Poterieae (= Sanguisorbeae) has mainly tricolporate and some hexacolporate (Sanguisorba) grains all with an operculum. Some genera (Agrimonia group) have striate pollen, but most have microverrucae and perforations. Within the tribe, a distinctive group of mainly south hemispheric genera (Acaena. Cliffortia, Cowania. Hagenia, Leucosidea, Margyricarpus, Polylepis, Tetrag/ochin) has tricolporate perforate pollen, often with a short colpus, sculpturing of macroverrucae and rugulae covered by micro~errucae. These pollen characteristics suggest a distinct evolutionary lineage. Re~ume.-L'etude en microscopie optique et electronique du pollen de genres representant toutes les tribus de Rosaceae revele une variate de formes et d'ornementations. Les pollens de tous les genres etudies son! des mona

Pollen Morphology and Ultrastructure of Calyceraceae

Lundellia

Pollen morphology of 13 species from all six genera of Calyceraceae (Acicarpha, Boopis, Calycera, Gamocarpha, Moschopsis, and Nastanthus) and representatives of the Campanulaceae and Goodeniaceae is examined with light (LM), scanning (SEM), and transmission (TEM) electron microscopy. Acicarpha, Calycera, and Nastanthus pollen grains are distinguished by angulaperturate apertures, colpar ledges and surface depressions between colpi known as intercolpar concavities (IC). Pollen of Gamocarpha and Moschopsis is tricolporate rather than angulaperturate and without an IC. Some species of Boopis are similar to the preceding genera (e.g., B. graminea), while others (e.g., B. gracilis) are angulaperturate with ICs. Structural features derived from fractured pollen in SEM and sections in TEM show pollen walls composed of prominent columellae ca. 0.55-1.1 mm high and ,0.25 mm wide. The columellae terminate distally into a complex of shortened columellae ca. 1.5 mm in length and are separated by an illdefined irregular internal tectum layer. This structural complex is well known in several tribes of the Asteraceae and referred to as the Anthemoid type. In those grains with an IC, the structure consists of essentially short (ca. 1 mm), unbranched columellae, similar to those found within the Asteraceae subfamily Barnadesioideae (Dasyphyllum and Schlechtendalia). Goodeniaceae (including Brunonia) pollen has angulaperturate apertures, spinules (i.e., minute spines), problematic IC and some structural similarity to Calyceraceae pollen. The tendency within Calyceraceae to develop colpar ledges, ektexine bridges, and ICs may be a synapomorphy uniting the family with Goodeniaceae. If the ancestral pollen type for the Calyceraceae, Asteraceae, and Goodeniaceae clade is the Gamocarpha type (convex intercolpar regions; no colpar ledges and no ektexine bridges), then the appearance of these structures within each family may be a synapomorphy supporting their close phylogenetic relationship suggested by molecular analyses.

(Vol.10, 2007-12) Pollen Morphology and Ultrastructure of Calyceraceae

2007

Pollen Morphology of the Aceraceae

Grana

Pollen of 40 Acer taxa and one species of Dipteronia were examined by light, scanning and transmission electron microscopy. Pollen grains in both genera are tricolpate or tricolporate of prolate to nearly spheroidal shape. Based on sexine pattern , four major pollen typ es were recognized and include striate grains, rugulose grains, microreticulate grains, and granular grains. Although th e family appears to be rather stenopalynous, several useful taxonomic variations occur.

Morpho-taxonomical studies of some Polyporate pollen grains

Pollen morphology of 24 species of 14 genera belonging to four families, viz., Amaranthaceae, Convolvulaceae, Malvaceae and Nyctaginaceae has been studied. The pollen grains of these taxonomically unrelated taxa, exhibit variation in colour, size, shape, exine ornamentation as well as in the number, position and character (NPC) of pores, but the pollen grains were usually polyporate and a few are polyzonocolporate. The pollen grains in the taxa of the family Amaranthaceae were small, non-spinous with polyporate exine, whereas, the pollen grains of taxa belonging to other three families were echinate. The maximum numbers of pores have been recorded in convolvulaceous pollens. Likewise, pollen grains of nyctagenaceous taxa can be distinguished from the pollens of other families on the basis of the size of pollen and spines. The pollens of the members of family Malvaceae exhibit different patterns of pore arrangements on the exine.

Comparative Pollen Morphology and Its Relationship to Phylogeny of Pollen in the Hamamelidae

Annals of the Missouri Botanical Garden, 1986

Data on pollen morphological features from 200 species in 20 families commonly included in the Hamamelidae and particular species in the Anacardiaceae and Salicaceae are presented in this paper. The basic descriptive analyses presented are derived from observations by light microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Thirty pollen characters showed some variability, and each of the species was scored for these characters. These data were analyzed and similarity cluster analyses were generated. Both an unweighted pair group and a complete linkage strategy dendrogram were produced. Three major clusters of families were defined, based on these analyses. Group I consists of Trochodendraceae, Cercidiphyllaceae, Eupteleaceae, Platanaceae, Hamamelidaceae (including Altingioideae), Eucommiaceae, and Myrothamnaceae. The Liquidambaroideae, Eucommiaceae, and Myrothamnaceae, while closest to Group I, can be viewed as intermediate between Groups I and II in complete linkage strategy and between Groups II and III in unweighted pair group strategy. Group IIâ€" consisting of Daphniphyllaceae and Fagaceae (excluding Not hofagus)â€" has a closer phenetic relationship to Group I than Group IIL Group III is the largest of these groups: it consists of Ulmaceae, Cannabaceae, Juglandaceae, Rhoipteleaceae, Betulaceae, Casuarinaceae, and Myricaceae. The Balanopaceae and Nothofagus are somewhat isolated and peripheral entities but hold together in both linkage strategies. Thirty pollen characters of 78 taxa were analyzed using PAUP to produce a cladistic tree. The outgroup used was Tetracentron, Three phylogenetically related groups sorted out, which are the same as those already recognized in the Groups I, II, and III mentioned above. Group I occurs at the base of the tree (primitive), and Group II occurs as intermediate between Groups I and III (derived). In general, these data support the relationships suggested by Barabe for the Hamamelidae, based upon vegetative and floral features and the classification of Cronquist. Leitneriaceae This survey ofpollen in the Hamamelidae was by Cronquist (1981), representing over 200 initiated with three primary goals in mind: (1) species (Didymelaceae, Urticaceae, Moraceae, morphological and Cecropiaceae are excluded from the cladistic assessing the relationships of fossil-dispersed and phenetic analyses). In addition, pollen data pollen with possible hamamelidaceous affinity, from the Anacardiaceae and Salicaceae are in-(2) to assess at which taxonomic level pollen eluded in the analysis. characters of extant hamamelidaceous taxa are In a survey as broad as that presented here, it useful in determining taxonomic position, and is often difficult to decide which taxa to include (3) to assess the phylogenetic relationships of taxa Members within the Hamamelidae as elucidated by pollen been placed in a number of subclasses, and a morphology and ultrastructure. comprehensive pollen survey of all the families To achieve these ends we used pollen data of the different classifications was not attempted [transmission electron microscopy (TEM) and here. We scanning electron microscopy (SEM)] from pub-system as a starting point and introduced into lished literature and added pollen data from 42 our analysis selected taxa from other subclasses previously uninvestigated taxa. We have amassed that have been suggested to be phylogenetically pollen data from 20 of the 24 families recognized related (e.g., Thome, 1973). Â» We wish to give special thanks to Robert Schwarzwalder for his many helpful suggestions and his consultation on the cladistic and phenetic analyses. We also thank Karl Longstreth, Linn Bogle, and Greg Anderson for their review of the manuscript. We thank Thomas Delendick of the Brooklyn Botanic Garden for material of the Eucommiaceae and the U.

A Contribution to the Pollen Morphology of Family Gramineae

2006

Pollen morphology of 20 species belonging to the 14 genera of the family Gramineae has been investigated using light microscope and scanning microscope. It is a stenopalynous in nature. Pollen grains mostly spheroidal, monoporate rarely diporate, ±circular, pores small operculate, non-operculate, annulate or non-annulate. Tectum areolate to scabrate. On the basis of exine ornamentations 5 distinct pollen types are recognized. Palynology do not correspond with tribal classification. However, palynology is significantly helpful at the specific and generic level within the tribes.

A Contribution to the Pollen Morphology ofCamellia(Theaceae)

Grana, 1993

The pollen morphology and ultrastructure of 20 species of Cat7iellia (Theaceae) representing the four subgenera were examined. The pollen is tricolporate, spherical to slightly oblate or prolate, with scabrate to rugulate exine sculpturing. The tectum is traversed by perforations that vary in diameter. Pollen wall structure is tectate-columellate, the columellae fused to a footlayer. Endexine is present in all, of the taxa examined. The greatest variation was observed in pollen size.

Pollen morphology in thePortulacaceae (Centrospermae)

Folia Geobotanica et Phytotaxonomica, 1992

Pollen of 110 species from 18 genera in the Po~ulacaceae has been examined by light and scanning electron microscopy, and a representative number by transmission electron microscopy. Three basic pollen types were found: 3-colpate with thick rectum and foot layer with prominent unbranched columellae and an extremely thin ende0dne; pantoporate with thick tectum and foot layer with branched columellae enclosing pores and an ende~ne that is one to two layers thick; pantocolpate with thin rectum and foot layer with broad, short unbranched columeUae and an inconspicuous endexine. All pollen types, however, have a spinulose and tubuliferous/punctate ektodne. Also, all the genera except three, Calandtinia H.B.K., Montia L. and Talinum ADANSON are stenopalynous. There is, however, no absolute correlation between pollen morphology and geographical distribution, although both the major centre of palynological diversity and the majority of all spedes with tricolpate grains occur in South America.

© TÜBİTAK Contributions to the Pollen morphology of the family Compositae (original) (raw)

Related papers