Pollen Morphology Research Articles

Pollen Morphology of Asteraceae from Garhwal Himalaya (Uttarakhand, India): Part I

Palynotaxonomy is crucial for understanding plant evolution, biodiversity, and ecological history by systematically classifying and identifying species based on pollen morphology. In addition, a regional pollen flora is crucial for precise pollen identification in various applied fields of palynology, including melissopalynology, aeropalynology, forensic palynology, paleopalynology, and copropalynology. In this communication, we explore the pollen morphology of 28 species of Asteraceae, employing both light (LM) and scanning electron microscopy (SEM). The results revealed that the grains were monad, isopolar, radially symmetric, tricolporate, and exhibited oblate-spheroidal to prolate-spheroidal shapes. The infratectum was found to be columellate, caveate, or noncaveate. The supratectum exhibited echinate or microechinate characteristics, with the exine surface showing perforate, microreticulate, or perforate regulate features. Among some species, a lophate pattern was observed, revealing two distinct variations: one characterized by a ‘15 lacunae type,’ while the other exhibited a ‘21 lacunae type’. Some unusual variations were observed in the aperture character among certain species, like occurrence of tricolpate grains and pollen dimorphism due to variation in aperture number. Light microscopic examination was preliminary for resolving columellar structure but it clearly showed double level of columella in some species. A cluster analysis, incorporating qualitative and quantitative features of pollen grains and an artificial pollen key have been set forth to distinguish studied species, supplemented by LM and SEM micrographs. The current findings have enriched the existing pollen database of Asteraceae and could play an important role not only in palynotaxonomy but also in allied fields.

Comparative pollen morphology of the genus Iberis L. (Brassicaceae) in Turkey and its taxonomic implications

In this study, we report the current palynological characteristics of Iberis taxa naturally distributed in Turkey. The pollen morphology of 10 native Iberis taxa was investigated across 35 populations. In the light of a reviewed taxonomical study on Turkish Iberis taxa, a detailed palynological description was provided for the genus. The palynological characteristics of Iberis taxa were examined by using scanning electron microscopy (SEM) and light microscopy (LM) to verify and confirm their diagnostic importance at a specific and/or generic level. We evaluated different characteristics including polar axis, equatorial axis, colpus length and width, Amb diameter, apocolpium, exine structure, and sculpture. Pollen characteristics were measured on 30 pollen grains from each specimen under light microscopy (LM). Detailed exine sculpture was also analyzed under scanning electron microscopy (SEM). Generally, the pollen grains of the genus Iberis are small to medium sized, radially symmetrical, isopolar, spheroidal, almost tricolpate, and rarely syncolpate or tetracolpate. The exine sculpture is reticulate, and the structure is semitectate. Two pollen types for the genus were identified based on the colpus surface feature: Iberis type-I (with non-ornamented colpus surface) and Iberis type-II (with ornamented colpus surface). Principal component analysis and cluster analysis were performed to reveal patterns and groupings within the related taxa concerning pollen morphology. It was found that pollen size may provide a limited but valuable metric to distinguishing Iberis species. However, due to the wide variation in some populations, it would be useful to have palynological data as well as chromosomal, molecular and macro-micromorphological data to resolve the complexity in the taxonomy of the genus.

Pollen morphology of the genera Basananthe, Deidamia and Efulensia of the tribe Passifloreae (Passifloraceae sensu stricto)

Passifloreae is the largest tribe of the family Passifloraceae sensu stricto. Within the tribe, palynological studies are mostly restricted to the largest genus, Passiflora, given its expressive number of species. Consequently, other genera within the tribe are frequently underexplored, particularly in terms of pollen characters. Given the importance of pollen morphology for the taxonomic classification of Passifloraceae s.s., it is necessary to describe the pollen characters of Basananthe Peyr., Deidamia Noronha ex Thouars, and Efulensia C.H.Wright. The analyzed characters included dispersion unit, polarity, size, shape, aperture number, aperture type, operculum type, and sexine ornamentation. Subsequently, 10 metric variables were subjected to principal component analysis. The results showed that the studied genera could be easily distinguished based on pollen characters, confirming the importance of palynology. The pollen of all studied species, regardless of the genus, had the same aperture number and type, namely 3-colporate. Sexine ornamentation ranged from microreticulate to reticulate, without spines. Here, pollen characters of Basananthe, Deidamia, and Efulensia were compared with those of closely related genera and Passiflora, contributing to a more comprehensive and up-to-date understanding of the group. The results confirmed the importance of analyzing pollen attributes for the taxonomy of Passiflora s.s.

Molecular, morphological, palynological and biochemical characterization of six accessions of two Mangifera indica L cultivars (Keitt and Ewais) native to Egypt

AbstractAccurate characterization of crops or fruits leads to successful improvements in breeding programs. Mango (Mangifera indica L.) is the second most common fruit in Egypt. It is a heterozygous plant; consequently, the possibility of incorrect characterization is significant. Therefore, this study used six accessions of two M. indica cultivars, ‘Keitt’ and ‘Ewais’, to produce precise molecular characterization and prove their genetic relatedness using inter-simple sequence repeat (ISSR) and start codon targeted (SCoT) markers. Pollen morphology was studied for the first time for these two Egyptian cultivars to determine their correlation. Morphological traits were quantitatively and qualitatively investigated. In addition, phytochemical analyses were performed to correlate the six mango accessions. One of these accessions (accession 3) was commercially identified as ‘Ewais’ cv., but the obtained result revealed that it does not belong to ‘Ewais’ cv. This finding was proved molecularly using ISSR and SCoT markers and morphologically. Similarly, phytochemical analyses revealed a difference between accession 3 and the other accessions under investigation. Polymorphic information content (PIC) and resolving power (RP) data revealed that the SCoT technique was more informative than ISSR for studying these genotypes of mango. Accordingly, the present findings prove the necessity for molecular, morphological, palynological, and biochemical investigations for accurate characterization of mango genotypes and genetic relatedness for improving breeding programs.

Pollen morphology of Taiwanese Asparagaceae species: insights from scanning electron microscopy

This study employed scanning electron microscopy to investigate the pollen morphology of Taiwanese Asparagaceae species, revealing that their pollen morphology closely aligns with that of other monocotyledonous plant taxa such as Asparagales, Commelinales, and Bromeliales. Despite the overall similarity, variations in pollen morphology across different genera were noted, highlighting its potential utility in classification. Unlike the wide diversity observed in flower morphology, Asparagaceae pollen morphology appears conservative, rendering it less effective as a taxonomic marker at the species level. The study also delved into the effects of pollenkitt and harmomegathy on pollen morphology, discovering that pollenkitt partially or completely coats the pollen surface, potentially complicating the identification of exine sculpture. Furthermore, the harmomegathic effect was observed to influence aperture dynamics. Consequently, observing both hydrated and dried pollen is advisable, as it can more accurately depict the pollen's aperture morphology and offer additional insights for pollen grain analysis.

Aspidistra luofushanensis (Asparagaceae), a new species from Guangdong, China

Aspidistra luofushanensis, a new species of Asparagaceae from northeast Guangdong, China, is described and illustrated. Morphologically it is similar to A. punctata but can be distinguished by the suberect or slightly inward bending perianth lobes, pollen sacs facing upwards, umbrella-like pistil, upper surface white to light purplish red of sigma with margin lobes revolute. The morphology, pollen morphology and color plates are provided for comparison.

Pollen morphology of Rosales from Brazilian forest fragments of Cerrado

ABSTRACT Rosales, a well-supported order of angiosperms encompassing heterogeneous plants, holds significant representation in Brazilian territory, particularly Cerrado regions. These areas are susceptible to human impact. In this context, pollen data is vital in supporting taxonomic and ecological studies for species preservation. We analyzed pollen grains from 15 native Rosales species found in Brazilian Cerrado forest fragments belonging to the Cannabaceae, Moraceae, Rhamnaceae, and Rosaceae families using light and scanning electron microscopy. The pollen grains underwent acetolysis, qualitative description, and measurements, with statistical analysis, including multivariate methods, applied to quantitative data. Qualitative findings were organized for pollen description and multivariate cluster analysis. Our observations revealed pollen grains in monads, isopolar, small to medium, with subcircular, circular, or subtriangular amb, and suboblate, oblate-spheroidal, or prolate-spheroidal. Apertures include 2–3-porate, 3-colpate, or 3-colporate, with long or short ectoapertures, lalongate or circular endoapertures. The exine is thin, microreticulate, psilate-perforate, microgranulate, nanoechinate, or striate ornamentation, with the sexine thicker than the nexine. The key characteristics distinguishing families are number, type of apertures, and exine ornamentation. Quantitative data (length and width of ectoapertures, equatorial diameter in polar view, and polar diameter in equatorial view) contribute to the understanding of the palynology of Rosales from forest fragments, as these characteristics allow us to identify species or groups of species. Our findings confirm Rosales as eurypalinous, while the genera analyzed demonstrate stenopalynous traits. The qualitative and quantitative characteristics of pollen identified here expand the morphological knowledge of the species and can be used to understand the relationship among them.

Sporopollenin Capsules as Biomimetic Templates for the Synthesis of Hydroxyapatite and β-TCP.

Pollen grains, with their resilient sporopollenin exine and defined morphologies, have been explored as bio-templates for the synthesis of calcium phosphate minerals, particularly hydroxyapatite (HAp) and β-tricalcium phosphate (TCP). Various pollen morphologies from different plant species (black alder, dandelion, lamb's quarters, ragweed, and stargazer lily) were evaluated. Pollen grains underwent acid washing to remove allergenic material and facilitate subsequent calcification. Ragweed and lamb's quarter pollen grains were chosen as templates for calcium phosphate salts deposition due to their distinct morphologies. The calcification process yielded well-defined spherical hollow particles. The washing step, intended to reduce the protein content, did not significantly affect the final product; thus, justifying the removal of this low-yield step from the synthesis process. Characterisation techniques, including X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermal gravimetric analysis, confirmed the successful calcification of pollen-derived materials, revealing that calcified grains were principally composed of calcium deficient HAp. After calcination, biphasic calcium phosphate composed of HAp and TPC was obtained. This study demonstrated the feasibility of using pollen grains as green and sustainable bio-templates for synthesizing biomaterials with controlled morphology, showcasing their potential in biomedical applications such as drug delivery and bone regeneration.

Palynology of Taxa of Crepis L. Genus Growing in Çanakkale, Türkiye

This study investigated the pollen morphology of the taxa belonging to the genus Crepis L. collected from various localities in Çanakkale in 2015. Wodehouse (1935) and Acetolysis (Erdtman, 1960) methods were used in the research. Pollen morphologies of 3 species and two subspecies belonging to the Crepis L. genus were defined according to light microscopy (LM) and scanning electron microscopy (SEM) examinations. In LM, pollens are monad, radially symmetrical and isopolar. Pollens are suboblate and oblate spheroidal, Amb shape is inter-hexagonal-subtriangular. The pollen of the genus is tricolporate. The view from the equator is circular and oval. In the examinations made with LM, the ornamentation is echinulophate. Pollen has 15 lacunae as 3 poral, 6 abporal, 6 paraboral. Ornamentation is echinulophate; the tectum surface is microperforate. SEM micrographs of C. smyrnaea and C. commutata pollen show depressions at the corners of the polar field. The collapses are located on the paraboral lacunae and are distinctly lacuna-like. As a result, in this study, palynological features of C. smyrnaea DC., C. micrantha Czerep., C. commutata (Spreng.), C. reuterana Boiss. & Heldr. subsp. reuterana taxa were studied for the first time. C. smyrnaea DC. ex Froel. was collected for the first time in Çanakkale within the scope of this study, according to the type records in Flora of Turkey.

Morpho-palynological assessment of the genus Terminalia L. (Combretaceae) in Egypt

Eleven Terminalia species growing in streets and gardens in Cairo (Egypt) were investigated for their pollen morphology. The study's objectives were to explore the variation among Terminalia species' pollen pheno-characters and to categorize the various species within this genus according to these pollen characteristics. The results showed that there are significant variations in the pollen morphological characteristics in the genus under study, and as a result, these traits can be regarded as eurypalynous. Each of the two main categories of Terminalia species - mono-morphic and di-morphic - includes various pollen morphologies, ranging from spheroidal to prolate with hexa-aperture that may be similar or of two types. For each of the eleven species, an identification key and a clustering phenogram for the fifteen major pollen features have been created. The aperture type, aperture similarity, and exine ornamentation are some of the crucial traits for the differentiation of the species examined while the pollen shape class has a poor diagnostic character. According to the unique characteristics of the pollen morphology of the Terminalia species, three groups and two subgroups were identified.

Studies on pollen micro-morphology, pollen storage methods, and cross-compatibility among grape (Vitis spp.) genotypes.

The knowledge of pollen morphology, suitable storage condition, and species compatibility is vital for a successful grapevine improvement programme. Ten grape genotypes from three different species, viz., Vitis vinifera L., Vitis parviflora Roxb., and Vitis champini Planc., were studied for their pollen structure and pollen storage with the objective of determining their utilization in grape rootstock improvement programs. Pollen morphology was examined through the use of a scanning electron microscope (SEM). The viability of the pollen was assessed using 2,3,5-triphenyltetrazolium chloride (TTC). In vitro pollen germination was investigated using the semi-solid medium with 10 % sucrose, 100 mg/L boric acid, and 300 mg/L calcium nitrate. The results revealed variations in pollen micro-morphology in 10 genotypes, with distinct pollen dimensions, shapes, and exine ornamentation. However, species-wise, no clear difference was found for these parameters. Pollen of V. parviflora Roxb. and Dogridge was acolporated and did not germinate. The remaining eight genotypes exhibited tricolporated pollen and showed satisfactory in vitro pollen germination. Storage temperature and duration interactions showed that, at room temperature, pollen of most of the grape genotypes can be stored for up to 1 day only with an acceptable pollen germination rate (>30 %). However, storage for up to 7 days was successfully achieved at 4 °C, except for 'Pearl of Csaba'. The most effective storage conditions were found to be at -20 °C and -196 °C (in liquid N2), enabling pollen storage for a period of up to 30 days, and can be used for pollination to overcome the challenge of asynchronous flowering. Four interspecific combinations were studied for their compatibility, among which V. parviflora Roxb. × V. vinifera L. (Pusa Navrang) and V. parviflora Roxb. × V. champini Planc. (Salt Creek) showed high cross-compatibility, offering their potential use for grape rootstock breeding. However, V. parviflora Roxb. × V. vinifera L. (Male Hybrid) recorded the lowest compatibility index among studied crosses. In the case of self-pollinated flowers from V. parviflora Roxb. and V. parviflora Roxb. × V. champini Planc. (Dogridge), pollen failed to germinate on the stigma due to male sterility caused by acolporated pollen. As a result, the flowers of these genotypes functioned as females, which means they are ideal female parents for grape breeding without the need for the tedious process of emasculation.

Pollen Morphological Studies on Selected Species of Family Dilleniaceae in Sri Lanka

Dilleniaceae is an angiosperm family including 11 genera and about 500 known species with a pantropical distribution extending into Australia. In Sri Lanka, four genera and 16 species including one introduced species have been reported in the family Dilleniaceae. Most of these species are endemic or native, while Schumacheria is an endemic genus. Morphological characters of the pollen grains are a significant taxonomic identification tool in the systematics of higher plants. The aim of the study is to provide detailed palynological descriptions of selected pollen species and maintain pollen reference collection. Four plant species, Dillenia retusa, Dillenia suffruticosa, Dillenia triquetra, and Schumacheria castaneifolia of the family Dilleniaceae (Genus Dillenia and Schumacheria) were collected from different localities in the wet zone including Nugegoda and Baduraliya during the period from September 2022 to November 2022. The voucher specimens were authenticated using revised handbook to the flora of Ceylon and deposited in the Herbarium of the Department of Botany, University of Sri Jayewardenepura, Sri Lanka. Fresh flowers or dried flowers were taken to collect pollen. Pollen grains were acetolysed and observed under Optika microscope (BG-Italy) after mounting on a clean glass slide using glycerin jelly with Basic fuchsin. Thirty pollen grains were used to determine the pollen size for each selected species. All measurements were taken within seven days of pollen preparation using OptikalSview (3.9.0.604) software. The shape, size, and surface features of pollen grains, as well as the length and width of the pollen and apertures and Polar/Equatorial ratios, were observed. Descriptive statistical analysis was performed using Minitab 18 software for the quantitative variables related to measurements of pollen obtained with light microscope. The ranges of variation were 15-22 μm for polar axis, 16-26 μm for equatorial axis, 0.8-3.5 μm for colpus width and 5.0-12.5 μm for colpus length. The pollen grains of all the species are monad, isopolar, and radially symmetrical. Pollen grains were identified as suboblate to oblate spheroidal, small or medium-sized, tricolpate (Dillenia spp.) or tetra-colpate (Schumacheria castaneifolia), with the surface ornamentation punctate to reticulate. The longest and widest pollen grains were reported in Dillenia suffruticosa (22.0×26.4 μm), while the smallest were observed in Schumacheria castaneifolia (15.2×16.4 μm). Based on the length of the longest spore axis, except D. suffruticosa all other species are categorized into small-size pollen. According to the results, the distinction between species can be determined using palynological features such as shape, size, and aperture type. 
 Keywords: Pollen morphology, Dilleniaceae, Palynology, Reference collection 

Pollen Morphology of Polygala L. (Polygalaceae) from Turkey and its Taxonomic Implications

Pollen morphology of Polygala taxa from the family Polygalaceae in Turkey is presented in this study. Pollen features of 18 species along with one undescribed species in the section Polygala were examined with light and scanning electron microscopy, 11 of which were studied and defined for the first time. Cluster analysis and principal components analysis were conducted to determine informative palynological characters and to discover similarities among the studied taxa. Based on qualitative and quantitative variables in the phenogram, the studied taxa were divided into three major clusters. Multivariate analyses revealed that apocolpium characters, including a psilate apocolpium, the presence of apocolpial lumens with granules and small depressions with psilate or rugulate walls are the most distinct features for discriminating Polygala taxa. Intraspecific variations in some pollen characters, such as the exine pattern and aperture membrane features, are reported for several taxa. Pollen morphological data obtained in the present study are compared with those from previous studies for a number of species, and the results are evaluated. In addition, the aperture number and its probable significance in the Turkish Polygala are considered for some taxa, with emphasis on their known pollination strategies.

Pollen morphology of Acanthoideae species from the Shivalik Foothills in Rajaji National Park (Uttarakhand, India).

Apart from its role in plant taxonomy, the understanding of pollen morphology is considered an essential interdisciplinary tool in diverse applied fields, including plant systematics, melissopalynology, aeropalynology, forensic palynology, paleopalynology, and copropalynology. In palynotaxonomy, it is frequently employed to classify and validate natural groups across a range of hierarchical levels, from higher categories down to the infrageneric level. The subfamily Acanthoideae, within the Acanthaceae family, consists of a diverse group of flowering plants that are distributed globally. The present study attempted a comprehensive analysis of the pollen morphology, employing both light microscopy (LM) and scanning electron microscopy (SEM), for a total of 13 Acanthoideae species from the Shivalik Foothills in Rajaji National Park (located in the northern Indian state of Uttarakhand, Western Himalaya). The findings indicated that the Acanthoideae is characterized by eurypalynous features, and the studied species exhibited pollen grains that were monads, radially symmetrical, and varied in size from small to large. The pollen grains were predominantly tricolporate or heteroaperturate, with porate occurrences being rare. The significant variation in exine sculpturing, including reticulate, coarsely reticulate, and bireticulate patterns, holds substantial taxonomic significance. The detailed presentation encompasses pollen morphological characters described with LM and SEM micrographs, along with a species-level identification key. RESEARCH HIGHLIGHTS: This article provides a thorough analysis of the pollen morphology of Acanthoideae taxa using both light microscopy and scanning electron microscopy, covering 13 species across 10 genera and revealing a broad spectrum of pollen characteristics, including size, shape, aperture type, and exine sculpturing. The microscopic investigation of these Acanthoideae species not only enhances our understanding of their pollen morphology but also aids in species identification through the development of a pollen-based key.

Pollen morphology of Norwegian hybrids of Sorbus

The genus Sorbus s.l. consists of small to medium‐sized trees primarily found in coastal areas, with three European hotspots of diversification: Fennoscandia, south‐east Europe and the British Isles. Taxonomic classification of Sorbus s.l. in Europe is still unresolved, and this study aims to address this issue by examining the pollen morphology of various Sorbus hybrids. Pollen morphology of 16 specimens from 13 species of Sorbus s.str., Aria and Hedlundia, some of them common, others are endemic and listed as threatened species, were studied. Measurements of the polar and equatorial axis of all pollen grains show that there are variations in pollen size and shape among different hybrids, with a correlation between ploidy levels and the equatorial diameter of the pollen. Surface structures of the pollen were observed using SEM. Principal component analysis (PCA) was performed to analyze the pollen characters, and the results show that it is possible to separate Aria from Sorbus and Hedlundia based on the length of the polar axis of the pollen grain, while the number of perforations is important for classification within Hedlundia. The study concludes that pollen morphology can be a useful tool for distinguishing between different Sorbus hybrids and can thus aid in understanding their past distributions.

The Study of the Pollen Grains of Various Species Belonging to the Genus Cousinia Cass. (Asteraceae) in Iraq

The genus Cuosinia Cass. is among the most common genera within the Asteraceae family. This genus contains an approximate range of 500 to 600 taxa. Pollen morphology analysis has proven to be a significant tool in the categorization of the Asteraceae, in addition to helping in the classification of specific genera and species under the family. An extensive examination of the pollen morphological features of six species belonging to the Cuosinia genus was carried out using both light and scanning electron microscopy. The pollen features that are beneficial for distinguishing various species of Cousinia based on characteristics instance form, dimension of the polar diameter and equatorial diameter, polar to equatorial axis ratio (P/E), exine thickness, sculpturing, and quantity of verrucae. Examination using light microscopy revealed that pollen grains were monads, tricolporate, isopolar, prolate-spheroidal, prolate, Sub-prolate. Using scanning electron microscopy, we categorized the pollen grains into three groups based on their exine ornamentation: group I (densely verrucate), group II (verrucate), and group III (loosely verrucate). Micrographs illustrating the morphology of pollen grains are accompanied by comprehensive descriptions of their structural characteristics. The pollen traits, such as morphology, exine thickness, and surfaces sculpturing, were found to be highly useful for classifying purposes.

Scanning electron microscopic exploration of intricate pollen morphology and antimicrobial potentials of gourd family.

This study employs scanning electron microscopy (SEM) to delve into the intricate pollen morphology of Cucurbitaceae (Gourd Family) species, unraveling the nuanced details of their structural features. Concurrently, the research investigates the antimicrobial potentials encoded within these pollen grains, shedding light on their possible applications in the realm of natural antimicrobial agents. Cucurbitaceae plants showcases significant antibacterial and antifungal potentials, underscoring its potential as a source for novel antimicrobial compounds. This research endeavors to provide a comprehensive analysis of pollen morphometry in 12 Cucurbitaceous species, with the primary goal of identifying pollen morpho-types to enrich the taxonomic understanding of the Cucurbitaceae. Following the Erdtman protocol, the study involved processing, measuring, and capturing pollen grains using SEM techniques. Qualitative data were analyzed to evaluate the variations in pollen types, size, and exine stratified sculptured layering. The pollen grains exhibit characteristics of being monads, ranging in size from medium to very large, with the prevailing shape being prolate-spheroidal in six species. Notably, the maximum polar axis diameter was recorded for Cucurbita pepo (106.3 μm), while the minimum was observed in Zehneria anomala (32.6 μm). The grains of Cucurbitaceae exhibit diverse surface patterns, including reticulate columellae, reticulate, verrucate-scabrate, verrucate-gemmate, echinate baculate, reticulate-perforate, and micro-reticulate. This SEM investigation illuminates the intricacies of Cucurbitaceae pollen morphology while concurrently highlighting their noteworthy antimicrobial potentials. HIGHLIGHTS: High-resolution imaging reveals complex pollen morphology. Identification of unique antimicrobial structures on Cucurbitaceae pollen (gourd family). Exploring medicinal potential: Antimicrobial properties of cucurbitaceae species.

The Pollen Status of Allergic Dysphania botrys (L.) Mosyakin & Clemants in Eskişehir, Turkey: A Case Study of Amaranthaceae Pollen

In this study, the pollen morphology of the allergic Dysphania botrys (L.) Mosyakin & Clemants (Amaranthaceae) taxon, which has a natural distribution within the borders of Eskişehir province, was investigated in terms of pollen morphology and allergic properties. Pollen grains of D. botrys are periporatae and sphaeroidal shaped. As a result of microscopic examinations, A/B=1.06 μm (W), A (polar axis): 4.08 µm; B (Equatorial axis): measured at 25.04 μm. The thickness of the Exine is 1.73 µm.

PRELIMINARY STUDY OF THE POLLEN MORPHOLOGY OF MALAYSIAN ZINGIBERACEAE (TRIBE ALPINIEAE) AND THE TAXONOMIC RELATIONSHIP

The family Zingiberaceae forms an important herbaceous layer in the tropical forests of Malaysia. From a phylogenetic point of view, certain genera of the problematic tribe Alpinieae are non-monophyletic and in need of more taxonomic evidence to support the classification. This study demonstrates how the palynological data could correlate with the proposed phylogenetic data, using representatives from the Malaysian species. The pollen morphology of 21 species from the tribe Alpinieae was investigated. Parameters including polarity, symmetry, shape, size, apertures, exine ornamentation, size of spine, type of spine apex, spine density, and distance between spine were analysed. The results demonstrated that the studied species were conveniently divided into two major groups based on the exine sculpturing of the spheroidal pollens, either psilate as in Etlingera and Hornstedtia, or echinate as in Alpinia, Conamomum, Meistera, Plagiostachys, Sundamomum, and Sulettaria. Hence, as far as the study is concerned, the main sculpturing is considered useful to generally distinguish the genera in the tribe.

Pollen and Capsule Morphological Studies on Verbascum Hybrids (Scrophulariaceae) in Mardin, Turkey and Their Taxonomic Importance

Verbascum (Scrophulariaceae, Lamiales), usually known as “Mullein”, is widely distributed in Eurasia and North Africa, but the highest taxa diversity is in Anatolia, the southern Balkans, the Middle East, the Caucasus and northwestern Iran and is represented by approximately 360 species in the World. As hybridization is very dense in the genus Vesbascum, the high frequency of morphological variations has been intricated in species delimitation. In this study, pollen and capsule morphology of three hybrid Verbascum taxa [Verbascum x calcicolum Hub.-Mor., V. x kotschyoides Hub.-Mor., and V. x nusaybinense Hub.- Mor.] were investigated. They are hybrids wild distributed in the province of Mardin in Southeastern Anatolia. Pollen slides were prepared according to the Woodhouse method, pollen and seed morphologies were examined with microscope. In general terms, aperture types were tricolporate, but also tricolpate aperture types were observed. The shapes of the pollen grains were determined as oblate-spheroidal and subprolate. The sculpture was reticulate in all cases. The seeds not developed. The capsules are pubescent, densely covered by branched hairs, or loosely by glandular hairs, depending on species. The results of this study showed that morphological features, such as pollen shape, polar axis length (P), equatorial diameter (E), aperture type, exine and intine thickness, colpus, and por measurement, show differences that can be taken into consideration in the systematic discrimination within the taxa. The capsule showed that substantial taxonomic insight can be gained from examining the capsule characteristics of Verbascum, particularly at the species level.