Systematic Implication Research Articles

A Detailed Study of Leaf and Pollen Micromorphology of Some Species of Parietaria and Its Systematic Implication (Urticaceae)

Parietaria L. is a genus comprised of 20 species distributed throughout temperate and subtropical areas of the world. The leaf and pollen characters of four species of Parietaria from different locations in Iran were investigated with light and scanning electron microscopy, in order to assess their diagnostic significance to provide additional evidence on species delimitation. All pollen grains were small in size and found to be porate. Most of the pollen characters, such as shape and sculpturing of pollen grains, exine diameter, were overlapped between species and indicated limited taxonomic value. The pore and annulus diameter could be provided additional taxonomic characters that can be used for species delimitation in the genus. Moreover, the leaf epidermis provided new qualitative data (laminar hydathodes, bladder-based trichomes) that could delimit the species. The characters like twin stomata and laminar hydathode observed in P. officinalis were reported for the first time in this genus.

Palyno-taxonomic approach through light and scanning electron microscopy for the identification of herbaceous Asteraceae species from Sikaram Mountain Pak-Afghan border.

Due to the diverse and rich taxa, Asteraceae needs to explore from the untouched area. In this study, the pollen study was intended to assess the taxonomic value for Asteraceous taxa growing on the Sikaram Mountain Pak-Afghan border. Both microscopic techniques (LM and SEM) play a significant role in the identification and classification of herbaceous species of Asteraceae for their taxonomic and systematic implication. Pollen was observed and measured for the 15 species of Asteraceae. For investigated taxa 15 pollen characters with size, shape, polar view, pollen type, aperture orientation, and exine sculpturing in the eurypalynous pollen. Consequently, the pollen grains are usually Tricolporate, triangular to circular in polar view, while, the shape of pollen varies from subulate, oblate, and prolate along with prolate to spheroidal whereas, sculpturing also varies from Scabrate to micro reticulate, echino-perforate, Scabrate to echinate, echinate to granulate and echinate were observed. Similarly, among the quantitative data minimum values of polar and equatorial were 15.8 ± 0.74 μm in Filago pyramidata and 17.85 ± 0.39 μm in Heteropappus altaicus was measured respectively, while; the length of the spine with the least value of 2.45 ± 0.31 μm in Hertia intermedia and highest with 7.55 ± 0.31 μm was observed in Cirsium wallichii. The Exine thickness is a minimum of 1.70 ± 0.35 μm in Launaea nudicaulis and a maximum of 5.65 ± 3.59 μm in Cirssium vulgare. In addition, the highest pollen fertility (87%) in Centaurea iberica while the highest pollen sterility (32%) was recorded in Cirsium verutum. Furthermore, clustering via UPGMA, PCA, and PCoA analysis was performed for the separation of closely related taxa. It is concluded from this research work that palynological study has a crucial role in taxonomic, pure, and applied sciences. This study can be further authenticated and improved by a Phylogenetic study based on chloroplast DNA analysis & whole genome sequencing. RESEARCH HIGHLIGHTS: Pollen ultrastructure among 15 Asteraceous taxa. Micromorphological attributes measured via LM and SEM. Exine sculpture elements patterns provide accurate identification. Taxonomic keys were developed for its systematics implications.

Comparative epidermal leaf anatomy of some Brassicaceae with emphasis on its systematic implication

Comparative epidermal leaf anatomy of some Brassicaceae with emphasis on its systematic implication

On the systematic implication of foliar epidermal micro-morphological and venational characters: diversities in some selected Nigerian species of Combretaceae

Foliar epidermal micro-morphology and venation patterns of eleven species representing four genera in the family Combretaceae revealed stable foliar anatomical characters that are diagnostic and are important in separating the taxa. Distinguishing characters of taxonomic significance in the cells and tissues structures of the species include epidermal cell shape, stomata type, stomata frequency, stomata index, trichome micro-morphology and frequency, areolation shape, vein micro-morphology as well as distribution of druses within areoles. Numerous epidermal striations on the abaxial surface of lamina are diagnostic for Combretum zenkeri while C. platypterum is distinctly separated from other taxa by the possession of staurocytic stomata in addition to the prominent a nomocytic and/oranisocytic stomata. The simple unicellular non-glandular trichomes in the genus Combretum indicate a generic attribute classificatory for members of the genus. Druses within the areoles classify C. platypterum, Terminalia catappa, T. superba and Quisqualis indica within and across the genera studied. This study which is in line with most previous studies revealed that characters of epidermal micromorphology andvenation patterns are important in the identification and separation of the taxa discussed, and that the placement of the species in each of their respective genus should be maintained.

Pollen morphology and its systematic implication on some species of <i>Artemisia</i> L. from Gilgit-Baltistan Pakistan

This study was accomplished to scrutinize the pollen morphology of 15 species of the genus Artemisia of the family Asteraceae from Gilgit-Baltistan region of Pakistan by means of scanning electron microscopy (SEM). Results revealed pollen grains of Artemisia species with tricolporate shape, and characterized by globular symmetry (ellipsoid ball shaped from equatorial side and three lobed rounds from polar view) with few exceptions. Additionally, the pollens are marked with reduced spinules on their surfaces which are diagnostic character for the genus Artemisia. In this study, seven micromorphological characters of pollen grains of 15 Artemisia species viz. shape of pollen, arrangement of spinules, exine sculpture, spinules base, equatorial width and polar length, were employed to construct a dendrogram following the consequential cluster analyses. In the dentrogram, four groups within the studied Artemisia species have been recognized. The pollen morphology of Artemisia could be a good taxonomic marker to cope with its taxonomic delimitations in combination with other floral and molecular attributes.

Nutlet micromorphology of the genus Marrubium L. and allies and its systematic implication (Lamiaceae: tribe Marrubieae)

Nutlet micromorphology of the genus Marrubium L. and allies and its systematic implication (Lamiaceae: tribe Marrubieae)

Seed morphology of 12 taxa of the genus Thalictrum L. (Thalictroideae, Ranunculaceae) and its systematic implication

The seed morphology and anatomy of 12 species, representing five sections of Thalictrum, were investigated by scanning electron microscopy (SEM) and light microscopy (LM) to evaluate seed features for use in systematic analysis. Considerable differences were observed in seed surface micromorphology and seed coat characteristics both among and within sections of the genus. MANOVA, MDA, and cluster analysis were used to unravel the morphology of seeds among the species. The characteristic seed features for species were found to be seed shape, size, testa thickness, exotestal cells and seed surface sculpture. The results indicated that the most prevalent seed coat sculpture among the studied species was reticulate and some species were reticulate at the margin and rugose in the center. Seed surface was without ornamentation and epidermal cells were mostly polygonal, rectangular or irregularly shaped. The testa thickness varied from two to six cell layers, and the exotesta was well characterized and rectangular to tangentially elongate in most of the species, except T. simplex and T. uchiyamae in which exotesta was poorly represented. It has been observed that species with a non-reticulate or poorly developed reticulate surface sculpture have a less protected seed coat and vice versa. The results of this study indicated that seed morphological features do not, in general, provide strong support to the sectional division of the genus, but that species within sections shared some comparable seed features.

쉬땅나무족(장미과) 화판표피의 미세형태학적 특성에 관한 연구

쉬땅나무족 15분류군의 화판의 미세형태학적 형질을 주사 전자현미경으로 관찰하여 화판 향축면, 배축면의 세포 외형, 배열, 수층벽, 큐티클의 미세형태를 자세히 기재하였으며, 분류학적, 계통학적 유용성을 검토하였다. 쉬땅나무족의 화판은 유두상 또는 원추형 유두상(PCS), 직사각형의 주름판상(TRS)로 확인되었으며, 향축면, 배축면의 화판 구조에 따라 크게 세 유형으로 구분하였다. Type I. PCS-TRS, Type II. PCS-PCS, Type III. TRS-TRS (향축면-배축면). 구분된 이들 유형과 수층벽, 큐티클 표면의 형태는 족 내 속간/종간 진단 형질로 유용하였을 뿐 아니라, 계통학적으로도 그 유용성이 확인되었다. 또한, 화판 표면의 세포의 미세형태와 수분매개자(곤충을 통한 충매)와의 연관성을 나타내는 추가적인 사례로 제시하였다. A comparative petal micromorphology of 15 taxa of tribe Sorbarieae was carried out using scanning electron microscopy (SEM) in order to evaluate their taxonomic and systematic implication. The characteristics of both adaxial and abaxial side of petal epidermal cells such as shape, arrangement, anticlinal wall and cuticular sculpture were described in detail. The Sorbarieae petal epidermal cells were identified as papillate or conical papillate (PCS) and rectangular-rugose tabular (TRS). Three types of petal micromorphology were found within the tribe based on the cell patterns of adaxial and abaxial side. Type I. PCS-TRS, Type II. PCS-PCS, Type III. TRS-TRS (adaxial-abaxial side). The petal epidermal cell types, anticlinal cell wall, and cuticular sculpture represent not only taxonomical importance for identification between or within the genera but also systematic implication. Moreover, this study provides a relation between petal epidermal cell pattern and insect pollinator (entomophily; melittophily) as an additional case.

Seed morphology of Ricotia (Brassicaceae) and its phylogenetic and systematic implication

In the present study, macro- and micromorphological characters of seeds in Ricotia L. (9 species and 30 accessions) were examined by light (LM) and scanning electron microscopy (SEM) to evaluate the taxonomic relevance of these traits. Four main seed surface types were detected (papillate, reticulate, reticulate-papillate and undulate) in Ricotia. In order to address the evolution of selected seed characters, ancestral character state reconstruction analysis was performed. The results indicate that the lack of wing and the reticulate surface are ancestral states for Ricotia. Finally, mapping of seed shape characters (but not the seed surface microsculpturing) among Ricotia species is concordant with current phylogenetic concepts of Ricotia.

Seed morphology of the subfamily Helleboroideae (Ranunculaceae) and its systematic implication

A comprehensive morphological and anatomical study was carried out on seeds of 28 species from three tribes and eight genera of subfamily Helleboroideae (Aconitum, Actaea, Caltha, Cimicifuga, Delphinium, Eranthis, Megaleranthis and Trollius) and two putatively related genera in Ranunculaceae (Adonis and Ranunculus) using scanning electron and light microscopy to evaluate seed characteristics for use in the examination of systematic relationships. Considerable differences were found in seed coat morphology and anatomy both among and within genera of the subfamily. There are four major types of seed coat surface: striate, lineate, colliculate and irregularly wrinkled. The shape of testal cells was either elongated rectangular, rectangular chiseled, irregular or polygonal to subpolygonal. The wall ornamentation was predominantly smooth and either without any ornamentation or having finely granulated or some ribbon like appendages. The mechanical layer of the seed coat was of the exotestal type except in all species of Eranthis, in which the seed coat mechanical layer was absent; such a seed coat was referred to as being an ‘undifferentiated seed-coat’. Maximum parsimony analysis of morphological features establishes three groupings within the studied genera: Aconitum/Delphinium, Actaea/Cimicifuga, and Caltha/Eranthis/Trollius/Megaleranthis. This study is congruent with the earlier groupings of the Helleboroideae based on morphology and also agrees in part with recent molecular studies. Our data convincingly support a close relationship between Caltha–Trollius–Megaleranthis and between Actaea and Cimicifuga. Another group supported strongly by the results of this study is Aconitum–Delphinium.

개나리족, 향선나무족, Myxopyrum속(물푸레나무과) 엽병의 해부학적 형질 및 분류학적 유용성

개나리족, 향선나무족, Myxopyrum속(물푸레나무과) 엽병의 해부학적 형질 및 분류학적 유용성

Pollen morphology of Campanula (Campanulaceae) and allied genera in Iran with special focus on its systematic implication

Pollen grains of 47 taxa of Campanulaceae including 35 taxa of Campanula that represent its five subgenera and nine sections are investigated. Moreover, five species and three subspecies representing three sections in Asyneuma and one species of each genera Legousia, Michauxia, Zeugandra and Theodorovia were studied by light and scanning electron microscopy. The basic shape of the pollen grains was spheroidal. The apertures vary from tri- to hexa-porate. The sculpturing pattern of exine was rugulate-echinate, rugulate-microechinate or in few species rugulate-microreticulate and microechinate. The most valuable characters for subgeneric classification were the length and density of echini. The length of echini were significantly long (> 2μm) in C. sclerotricha, Legousia falcata and Michauxia laevigata. Pollen grains show low variation in different species of subgen. Rapunculus, but were variable among different species of some groups, such as sect. Rupestres, probably indicating their non-monophyly despite homogeneity with respect to other morphological characters. Pollen morphology does not support recognition of Asyneuma, Legousia, Michauxia, Symphyandra, Theodorovia, and Zeugandra as separated from Campanula, since none of them exhibit any unique feature.

Pollen morphology of Quercus (subgenus Quercus, section Quercus) in Iran and its systematic implication

For the first time, pollen morphology of 9 (4 spp. and 5 subspp.) taxa representing lobed leaved oaks of Iran in the family of Fagaceae has been examined and illustrated using light microscopy and scanning electron microscopy of acetolysed material. Detailed pollen morphological characteristics are given for <em>Quercus</em> section. The pollen grains are single, isopolar, radially symmetrical, tricolpate, tricolporoidate or tricolporate. Pollens were studied to show all possible characteristics like shape, size, apertures, wall thickness, etc., with special reference to the specific features of each pollen type such as structural, sculptural and suprasculptural patterns. There is considerable variation in pollen morphology between taxa so that, three types of pollen shape, five types of structural pattern, two types of sculptural pattern, five types of suprasculptural pattern and three types of perfora distribution are defined. Furthermore, the relationship between pollen morphology and taxonomy is discussed. Overall, pollen characters are shown to be a useful and informative tool for assessing taxonomic position within <em>Quercus</em> section in Iran.

Comparative morphology of the eggs in some Panorpidae (Mecoptera) and their systematic implication

The egg ultrastructure of 12 species in three genera of Panorpidae: Panorpa Linnaeus, Neopanorpa Weele and Sinopanorpa Cai & Hua, was examined using scanning electron microscopy. This is the first time the egg characters have been studied in detail for this family. The results show that egg morphology can be utilised for panorpid taxonomy both at the generic and specific levels. In the species investigated, the egg chorion is covered with a network of extrachorion. Several micropyles were visible on the anterior pole of the eggs after the extrachorion was removed. Neopanorpa eggs differ from the other two genera by neighbouring ridges of exochorion, which are separate and independent. The eggs of Sinopanorpa and Panorpa have only one fused ridge between every two adjoining polygonal cells. The eggs of Sinopanorpa have a network of ridges with even top edges, the granules within the cells being small and uniform. However, the eggs in the nine species of Panorpa are very diverse in morphology, reaffirming the heterogeneity and paraphyly of Panorpa, which may need further systematic analyses.

Foliar epidermal anatomy and its systematic implication within the genus Sida L. (malvaceae)

Micro morphological investigations of the foliar epidermal anatomy, particularly the diversity and distribution of glandular and eglandular trichomes on leaves of Sida alba L., S. alii S. Abedin var. alii, S. cordata (Burm. F.) Brss, S. mysorensis Wight and Arn, S. ovata Forssk. S. spinosa L and S.yunnanensis S.Y.Hu have been carried out to assess the systematic relevance of epidermal features and trichome diversity within the genus Sida L. Configuration of epidermal cells is polygonal to irregular with smooth or undulating outline. Leaves are amphistomatic and amphitrichomic. Six diverse morphological types of glandular and eglandular foliar trichomes are described. Stellate and peltate types of trichomes are characteristically found in all taxa studied. S. alii and S.spinosa are distinct in having long-stalked and short-stalked capitate trichomes. S. mysorensis is characterized by multicellular uniseriate trichomes, but these are not observed in other taxa of genus Sida. The results of foliar epidermal anatomy, especially type, distribution and structure of foliar trichomes are of high systematic value in this genus of family Malvaceae.

Trichome micromorphology of Iranian Stachys (Lamiaceae) with emphasis on its systematic implication

Trichomes of 37 taxa of the genus Stachys and one species of Sideritis ( S. montana) were examined using light and scanning electron microscopy. The indumentum shows considerable variability among different species, but is constant among different populations of one species, and therefore, affords valuable characters in delimitation of sections and species. The characters of taxonomic interest were presence of glandular and non-glandular trichomes, thickness of the cell walls, number of cells (unicellular or multi-cellular), presence of branched (dendroid) trichomes, presence of vermiform trichomes, orientation of trichomes in relation to the epidermal surface, curviness of trichomes, and presence of papillae on trichome surface. Two basic types of trichomes can be distinguished: glandular and non-glandular trichomes. The glandular trichomes can in turn be subdivided into subtypes: stalked, subsessile, or sessile. The stalks of the glandular trichomes can be uni- or multi-cellular. Simple unbranched and branched trichomes constitute two subtypes of non-glandular trichomes. Our data do not provide any support for separation of Sideritis from Stachys. The following evolutionary trends are suggested here for Stachys: vermiform trichomes with stellate base are primitive against vermiform trichomes with tuberculate base, long vermiform trichomes are primitive against the short simple trichomes, appressed trichomes are advanced against spreading ones, and loss of glandular trichomes is advanced against their presence. Overall, trichome micromorphology is more useful in separation of species within sections rather than characterizing large natural groups known as sections, except for few cases.

Pollen morphology of Stachys (Lamiaceae) in Iran and its systematic implication

Pollen grains of 30 taxa of the genus Stachys (29 spp. and one subsp.), representing 9 of the currently recognized sections and 1 species of the closely related genus Sideritis ( Si. montana) distributed in Iran were examined by light and scanning electron microscopy. Twenty-eight taxa are studied for the first time under aspects of pollen morphology. The basic shape of the pollen grains in most taxa studied is prolate-spheroidal, but subprolate, spheroidal and oblate-spheroidal pollen grains can also be found in few species. The grains are usually tricolpate (the amb triangular), but also tetracolpate (the amb circular to more or less square) in some species ( S. iberica, S. atherocalyx and Si. montana). The surface is microreticulate (the frequent type), reticulate, perforate, foveolate-psilate or foveolate. The lumina are separated by smooth or sinuate muri which make them polygonal, more or less rounded and elongate. Major pollen morphological features of the taxa studied are compared and discussed on the basis of taxonomical concepts. In some cases, these characters are useful in delimitation of formerly introduced sections while they mostly provide further characters in separating related species from each other. For example, all members of S. sect. Aucheriana are characterized by elongated lumina. Based on the oblate-spheroidal shape of its pollen as well as tetracolpate aperture type, the results of the present study confirm sect. Pontostachys as including S. angustifolia, S. iberica, S. sparsipilosa as well as S. atherocalyx. Our results also suggest that although some species like S. fruticolosa and S. lavandulifolia are morphologically well characterized, they cannot be separated from other species of Stachys based on pollen morphology.

A palynological study of Galium L. (Rubiaceae) in Egypt and its systematic implication

AbstractA pollen morphological investigation of eleven species and one subspecies of the genus Galium L. from Egypt were undertaken by using light microscope (LM) and scanning electron microscope (SEM). Pollen shape, size, exine ornamentation, number of apertures present powerful characters for distinguishing between species. The pollen grains were zonocolpate. The number of colpi ranges from 5 to 10. Their shape varies from prolate spheroidal, oblate spheroidal, spheroidal to suboblate. Three groups can be distinguished based on the size pollen grains. It was found used to distinguish between closely related species G. aparine and G. spurium and between G. tricornutum and G. ceratopodum. Two different types of exine ornamentation were recognized. The ornamentation was found useful to distinguish among closely related species such as Galium aparine and G. spurium. A key for the identification of the investigated taxa based on pollen grains characters is provided. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Phyllotaxis of vegetative shoots, lamina rotation and their systematic implication in Magnoliaceae

Phyllotaxis in vegetative shoots and lamina rotation of Magnoliaceae are described. Most genera in Magnoliaceae investigated (except Parakmeria, Manglietiastrum and Pachylarnax) show lamina rotation. Paraphoric, a new type of lamina rotation differing from four other types depicted by Charlton is clarified. Manglietia, Parakmeria, Manglietiastrum, Talauma, section Gwillimia and Rytidospermum in subgenus Magnolia, shoots of Woonyoungia, section Theorhodon and Liriodendron have spiral phyllotaxis, however Magnolia section Oyama and Maingola, Alcimandra, Michelia, Paramichelia, Tsoogiodendron, buds of Woonyoungia, section Theorhodon and Liriodendron have distichous phyllotaxis. The systematic implication of vegetative shoot phyllotaxis and lamina rotation in Magnoliaceae is discussed in this paper.

The Microcharacteristics of Leaf Surface and Its Systematic Implication in Lysimachia

The microcharacteristics of leaf surface in Lysimachia were investigated by using light microscope (LM) and scanning electron microscope (SEM). Based on the features of leaf surface, those plants were obviously classified into two types, heterogenea-type and capillipes-type. The features of leaf, such as the presence or absence of the glands, the color and distribution of the glands, and the ornamentation of adaxial side, are quite constant at intraspecific level, but remarkably varied at interspecific level, which might have significant taxonomic value for species identification. In the 21 investigated species, 1 species was from Subgen. Idiophyton, 11 species from Subgen. Lysimachia, and 9 species from Subgen. Palladia. Since 2 types of leaf surface structure were found both in Subgen. Lysimachia and Subgen. Palladia, they could not be used as the characters to define subgenus.