Reticulate Exine Research Articles

In vitro studies on the pollen viability and germination of Impatiens cordata Wight. an endemic species of the Southern-Western Ghats

Impatiens cordata is an endemic balsam in the southern Western Ghats. The present work aimed to study pollen morphology, fertility, viability, cytology, and in vitro pollen germination studies of I. cordata. The study also focused on finding a relationship between pollen viability and germination. The results revealed that the I. cordata pollen grains are elliptical and quadrangular. The pollen grains are bicellular, mainly tetracolpate, with some tricolpate occurrences, and have reticulate exine ornamentation. Brew baker’s medium supplemented with 5% sucrose had the most remarkable ability to germinate in vitro. The stain and the number of days significantly affect germination. The peak of pollen viability was observed on the day of anthesis. The results of the Alexander stain were more strongly correlated with in vitro germination and suggested that for pollen viability studies, the Alexander stain is considered the best stain compared to others.

Pollen Morphology of Nymphaeaceae (S.L.)

Eleven taxa of the Nymphaeaceae (s. l.) belonging to five genera viz., BRASENIA , EURYALE , NYMPHAEA, NELUMBO and VICTORIA were examined for the present study. NELUMBO pollen is quite distinct from other genera of Nymphaeaceae in having 3-zonocolpate apertures and reticulate exine. In VICTORIA pollen are shed as permanent tetrads, while in BRASENIA, EURYALE and NYMPHAEA pollen are produced as monads. The pollen grains are l-(2)-aperturate, zoni or zonasulculate and hetero-or iso-polar. Exine surface is spinate, tuberculate, verrucate, granulate or psilate. The application of pollen characters within the family is discussed.

Comparative Anatomy, Pollen and Seed Morphology of Two Verbascum Varieties (Scrophulariaceae) and Their Taxonomic Significance

In this study, the anatomical, palynological, and seed micromorphological traits of two Verbascum varieties found in the Southeastern Anatolia Region were investigated. These variations are V. sinuatum subsp. sinuatum var. adenosepalum Murb. and V. sinuatum subsp. sinuatum var. sinuatum L. Cross-sections from the taxa's roots, stems, and leaves were viewed under a light microscope for anatomical study. The xylem components play a significant role in the taxonomic root portions. The pith area is a broad region in stem sections, and the upper portion of the epidermis cells is encircled by a distinct indented cuticle layer. The leaves' primary vein is represented by open collateral bundles. Pollen grains in Verbascum sinuatum subsp. sinuatum var. adenosepalum are tricolporate-tricolpate, prolate-spheroidal, and have reticulate exine ornamentation. Similarly, pollen grains in V. sinuatum subsp. sinuatum var. sinuatum are tricolporate-tricolpate, prolate, and have reticulate exine ornamentation. The brown seeds of V. sinuatum subsp. sinuatum var. adenosepalum and V. sinuatum subsp. sinuatum var. sinuatum have an alveolate, deep and wide posterior region, a truncated beak, and a prismatic-oblong shape. The ornamentation of the seed coat is made up of irregular polygonal cells that have noticeable and dense vesicles. The importance of a few traits in the Verbascum variety delimitation has been investigated in this study. For the purpose of supporting ancestral traits in the infrageneric classification and helping with genus systematics, some pollen and seed characters which are typically connected to pollen and seed micromorphological and anatomical patterns can be applied.

A taxonomic revision of Rhizophora L. (Rhizophoraceae) in Thailand.

A taxonomic revision of Rhizophora L. (Rhizophoraceae) in Thailand is presented. Two species, R. apiculata Blume and R. mucronata Poir., are enumerated with updated morphological descriptions, illustrations and a taxonomic identification key, together with notes on distributions, habitats and ecology, phenology, conservation assessments, etymology, vernacular names, uses, and specimens examined. Three names in Rhizophora, are lectotypified: R. apiculata and two associated synonyms of R. mucronata (i.e., R. latifolia Miq. and R. macrorrhiza Griff.). R. longissima Blanco, a synonym of R. mucronata, is neotypified. All two Rhizophora species have a conservation assessment of Least Concern (LC). Based on the morphological identification, these two species can be distinguished from one another by the shape and width of the leaf laminae and the length of a terminal stiff point of the leaf laminae; the type and position of the inflorescences and the number of flowers per inflorescence; the character and color of the bracteoles; the presence or absence of the flower pedicels; the shape of the mature flower buds; the shape, color, and texture of the sepals; the shape, character, and the presence or absence of hairs of the petals; the number of stamens per flower; the size of the fruits; the color and size of the hypocotyls; the color and diameter of the cotyledonous cylindrical tubes; and the color of the colleters and exudate. The thick cuticles, sunken stomata, large hypodermal cells, and cork warts are adaptive anatomical features of leaves in Rhizophora that live in the mangrove environments. The pollen grains of Thai Rhizophora species are tricolporate, prolate spheroidal or oblate spheroidal shapes, small-sized, and reticulate exine sculpturing.

Palynological studies of some species of the genus Cuscuta with emphasis on taxonomy

The main objective of this research was to conduct a comparative pollen morphological analysis of some representatives of the genus Cuscuta in relation to taxonomy. Investigations of 38 species and 1 variation revealed that not only the number, but the colpi length, as well as the exine ornamentation (at the SEM level), can be regarded as a diagnostic feature. For all the taxa studied, the common zonocolpate type of pollen was observed, represented by three variations: I) colpi long; II) colpi of medium length; III) colpi short. In combination with colpi length, variations in the number of colpi were also identified, such as: I) 3(4)-zonocolpate pollen grains with long colpi (in most of the species studied from subgenera Grammica and Cuscuta, as well as in C. monogyna from the subgenus Monogynella); II) 4(3)-zonocolpate pollen grains, with long colpi (C. cristata from subgenus Grammica); III) 3-zonocolpate pollen grains both with long colpi and colpi of medium length (C. abyssinica from subgenus Cuscuta and C. africana, C. angulata from subgenus Pachystigma); IV) 3-zonocolpate pollen grains with colpi of medium length were noted for species from all four subgenera (C. cassytoides, C. lupuliformis from subgenus Monogynella, C. kotschyana from subgenus Cuscuta, C. nitida from subgenus Pachystigma and C. jalapensis, C. rostrata, C. suaveolens from subgenus Grammica); V) 3–4- or 4-zonocolpate, with short colpi (C. lehmanniana and C. gigantea from subgenus Monogynella respectively); VI) 5–6-zonocolpate, with short colpi (C. reflexa from subgenus Monogynella). Using SEM, three main types of exine ornamentation were also identified: perforate, foveolate and reticulate. The last type in the vast majority of the cases was presented in combination with echinae (rarely with spines or granules). The data revealed that the presence of the significant similarity of palyno-morphological characteristics in representatives of the subgenera Cuscuta, Pachystigma and Grammica, with the exception of the species Lepidanche adpressa (syn. C. compacta), makes it difficult to create an identification key at the level of individual subgenera. Pollen features can be most clearly used only to distinguish the subgenus Monoginella, reflecting its certain isolation within the entire Cuscuta genus. The presence of a highly specialized reticulate exine ornamentation in Lepidanche adpressa (syn. C. compacta), not identified for the pollen of any of the studied taxa of the subgenus Grammica, indicates a significant proximity of this species to the subgenus Monogynella. For the species C. reflexa, the obtained palyno-morphological data are consistent with the previous opinion about the separation of this species, as well as its more advanced position within the genus Cuscuta.

Knockout of eight hydroxyproline-O-galactosyltransferases cause multiple vegetative and reproductive growth defects

Arabinogalactan-proteins (AGPs) are a family of hyperglycosylated hydroxyproline-rich cell wall proteins found throughout the plant kingdom. To date, eight Hydroxyproline-galactosyltransferases (Hyp-GALTs), named GALT2-GALT9, are known to catalyze the addition of the first galactose sugar to Hyp residues in AGP protein cores. The generation and characterization of galt23456789 octuple mutants using CRISPR-Cas9 gene editing technology, provided strong reverse genetic evidence that AG glycans are essential for normal vegetative and reproductive growth, as these mutants demonstrated stunted growth, greatly delayed flowering and significant defects in floral organ development and morphogenesis. Compared to the lower seed set of galt25789 quintuple mutants being more so contributed by female gametophytic defects, dramatically low seed-set of octuple mutants was largely due to impaired male reproductive function, specifically due to shorter filaments, delayed anther dehiscence, and large decreases in pollen quantity and viability. Octuple mutant pollen had severely distorted reticulate exine, tectum patterning and intine thickness. Reduced amounts of galactose and arabinose in overall lower amounts of β-Yariv precipitated AGPs illustrated how biological functions of AGPs are affected by abnormal glycosylation.

PALYNOLOGICAL DIVERSITY OF POLLEN MORPHOLOGY IN ENDEMIC NORTHERN IRAQI HYPERICUM SPECIES (HYPERICACEAE)

The presented research investigated the pollen morphology of endemic Iraqi Hypericum species. The study revealed phenotypic features of pollen grains in the polar and equatorial views and their quantitative and qualitative characteristics. The results showed that the pollen grains of the genus Hypericum were radially symmetrical and isopolar, and their apertures were simple and tricolporate, except the species H. davisii, distinguished as tetracolprate. Dividing the studied species based on pollen grain sizes comprised two groups. Small pollen grains with an average length of the equatorial view ranged between 10–16 μm in H. lysimachioides and H. vermiculare. Medium-sized pollen grains with an average extent between 17–26 μm emerged in the species, i.e., H. retusum, H. triquetrifolium, H. perforatum, H. lydium, H. tetrapterum, H. asperulium, H. scabrum, and H. davisii. Pollen grains, also divided according to the P/E ratio, had two main groups. The pollen grains were subprolate and spherical, with the exine sculpturing examined by a scanning electron microscope (SEM), and isolated into four groups: 1) microreticulate reticulum, including H. asperulium, H. lydium, and H. vermiculare, 2) perforate, i.e., H. retusum, H. scabrum, H. tetrapterum, and H. triquetrifolium, 3) psilate with H. perforatum and H. davisii, 4) and reticulate exine sculpturing in H. lysimachioides, all isolated from the rest of the species. SEM images showed the thickness of exine ranged from 0.5 to 2 μm. The topical study also added H. davisii as a new species with no previous records in Iraq. This pollen study added valuable data for taxonomy and suggested that it should proceed with its first-time registration in Iraq. The pertinent research could provide a taxonomical key for Hypericum species in Iraq.

SEM-based study for palynological and pollen germination of Lilium longiflorum cv. Pavia

Pollen is the first choice of germplasm curator, geneticist, breeder and physiologist for conservation and crop improvement programs. A pollen palynological attributes and pollen germination study of Lilium longiflorum cv., 'Pavia' was conducted using scanning electron microscope (SEM). Various morphological characteristics were studied. The results showed that pollens were much alike in ultra-morphology with elliptical to ellipsoidal shape, reticulate exine and single germination ditch. The pollen viability was tested by the wet room method with 3 dyes; Acetocarmine, TTC, Lugol's iodine and 49.66% pollen viability was recorded with Acetocarmine dye; which suggested acetocarmine stain can be as a quick test method for pollen viability. The pollen germination ability was examined at set intervals, thereby establishing the dynamics of this process for 72 hours. Pollens collected just 1 h after anthesis were recorded with highest germination (85%) compared to pollen harvested before or one day after. The suitable medium for pollen germination was 3% sucrose and 15% PEG that recorded with highest pollen germination (95%) after 72 h of inoculation. Understanding evolutionary ecology and the sterility problem and designing hybridization programmes in cross-breeding necessitates a thorough understanding of pollen morphology and viability. Pollen ultra-morphology traits could be helpful in determining the evolutionary relationship of lilies.

Pollen morphology of the early branching papilionoid legume genera Harleyodendron, Holocalyx and Uribea

In this study, pollen grains of Harleyodendron unifoliolatum, Holocalyx balansae, and Uribea tamarindoides, three monospecific genera with Neotropical distribution belonging to the clade Exostyleae, one of the basal lineages of the family Leguminosae, subfamily Papilionoideae, were analyzed. The palynological material was acetolyzed and analyzed under light microscopy (LM) and scanning electron microscopy (SEM). Under LM, small and medium-sized pollen grains were observed, which showed a prolate-spheroidal to prolate shape, 3-colporate, microreticulate and reticulate exine, sexine and nexine of equal thickness in Harleyodendron and Holocalyx, while the sexine was thicker than nexine in Uribea. Analysis under SEM showed finely granulate, psilate, and granulate apertural membrane, while the exine ornamentation varied from perforate-microechinate in Harleyodendron, to perforate in Holocalyx, while in Uribea showed an irregular relief and granular projections on the perforate tectum. The pollen morphology of these species is similar to each other, varying in sexine/nexine ratio, apertural membrane, and exine ornamentation. Harleyodendron has a finely granulate apertural membrane, sexine and nexine of equal thickness, and a perforate-microreticulate exine ornamentation, Holocalyx shows a psilated apertural membrane, sexine and nexine of equal thickness, and exine ornamentation perforate, and Uribea has a granulate apertural membrane, sexine thicker than nexine, and exine ornamentation with granular projections.

Pseudopollen in Camellia oleifera and its implications for pollination ecology and taxonomy.

In 1997, Tsou described the special differentiation of the connective tissues of some species of Theaceae to produce single-celled powders with unique patterns called pseudopollen. The purpose of this study was to investigate the morphological structure of the pseudopollen of Camellia oleifera (Theaceae) and to study the morphology of pseudopollen in seven other Camellia species. Scanning electron microscopy, paraffin section, light microscopy, transmission electron microscopy, histochemistry. C. oleifera pseudopollen was similar to normal pollen in macroscopic morphology but different microscopically. The normal pollen was starch-rich and yellow, with mostly reticulate exine ornamentation. In contrast, the pseudopollen was a white powder, single-celled and rich in protein, with parallel unbranched ridge lines on the outer wall, and originated from the parenchyma of the connective tissues. There are also differences in the micro-characteristics of normal and pseudopollen among different species in Camellia. There are great differences in morphological structure between C. oleifera and other species in Camellia normal pollen and pseudopollen; these results may indicate that the pseudopollen can be used as a taxonomic basis for Camellia, and the macroscopic similarity between pseudopollen and pollen and histochemical characteristics of pseudopollen can be a pollination strategy.

Pollen morphology and its implication in the taxonomy of some selected taxa of the bi and tri-ovulate Euphorbiaceae of the Hainan Island by using multiple microscopic techniques.

The family Euphorbiaceae is one of the most taxonomically complex and diverse family among the angiosperm. Therefore, this study aims to document the pollen morphology of the Euphorbiaceae taxa collected from different geographical regions of the Hainan Island South China, to strengthen the taxonomy and support the subfamilial classification. The Euphorbiaceae includes 23 species and 10 genera of the bi-ovulate subfamily Phyllanthoideae and tri-ovulate Crotonoideae, Euphorbioideae, and Acalyphoideae were examined under light and scanning electron microscopy. The principal component analysis was performed by using six variables to show variation and relationships between the species. A significant variation was found in the pollen morphology (exine and colpus sculpturing). The croton-type pattern of the pollen was found the diagnostic trait of the Crotonoideae. The Euhphorboideae taxa were mostly homogenous however, variation was found in the muri pattern. The Acalyphoideae, have fossulate scabrate and verrucate exine sculpturing that can delimit from the rest of sub-families. The Phyllanthoideae, showed reticulate exine, tri to tetra-colporate having various colpus morphology. The maximum pollen size was found in Croton hirtus (59.49 × 60.86 μm) and minimum in Acalypha indica (10.86 × 73 μm). Similarly, the maximum colpus width was observed in Euphorbia pulcherrima (8.3μm). Hence pollen traits have relevance in the taxonomy and phylogenetic of the family to define species boundaries at various taxonomic levels. This study can support and strengthen the taxonomy of subfamilies and fill the palynological gap of these taxa in Hainan Island and will contribute to future systematic studies of the Euphorbiaceae.

Pollen morphology of Galactia P. Browne and related genera (Papilionoideae, Leguminosae), with emphasis on Brazilian representatives

Galactia is a pantropical genus, which is part of the Galactia clade, and together with the genera Betencourtia, Caetangil, Cerradicola, Collaea, Lackeya, Nanogalactia, and Rhodopis, it maintains a taxonomic relationship that has already been the focus of previous studies. However, the palynology of these groups has not been extensively studied, with gaps in pollen descriptions. Thus, a palynological study of 30 species belonging to Galactia and related genera was performed. For this purpose, pollen grains were acetolized using the standard methodology, subjected to scanning electron microscopy analysis, and then quantitatively and qualitatively evaluated. Generally, pollen grains of this genera are medium or large size, isopolar or heteropolar, 3-colporate, and may have microreticulate or reticulate exine. Pollen data for Rhodopis and Nanogalactia agree with the most recently proposed circumscription of these genera. Other genera exhibited similar pollen characteristics; however, the diameter of the lumen, associated with other pollen characteristics, proved to be important for the differentiation of the genera. Thus, the pollen morphology provided information that contributes to the description of the genera, mainly Brazilian representatives of Galactia and related genera.

Pollen morphology of Ellisiophyllum and Sibthorpia (Plantaginaceae, tribe Sibthorpieae) and phylogenetics of the tribe

Pollen morphology of six species belonging to genera Ellisiophyllum and Sibthorpia (Plantaginaceae tribe Sibthorpieae) was studied using light and scanning electron microscopy. The data were analyzed in the light of the first phylogenetic analysis including all but one species of the tribe using DNA sequence data from nuclear ribosomal (ITS) and plastid trnL-F region. Pollen grains in representatives of this tribe are 3-colpate, occasionally 3-porate, suboblate to prolate; mainly medium-sized, rarely small. One major pollen type (3-colpate) is recognized in the tribe. Within this pollen type, six subtypes are distinguished based on their exine sculpture, pollen grain size, length of the apertures, and exine thickness. The obtained results confirm that pollen characters are useful for species identification. Palynomorphological data are consistent with the results of the molecular phylogenetic analyses. All studies support a sister relationship of the widespread European Sibthorpia europaea with the widespread South American Sibthorpia repens and a sister relationship of two insular species, the Balearic Sibthorpia africana and the Madeiran Sibthorpia peregrina. Pollen grains in the tribe Sibthorpieae have both reticulate exine sculpture characteristic for representatives of the Russelieae–Cheloneae–Antirrhineae clades of Plantaginaceae, and also nanoechinate sculpture, which is typical for the Veroniceae and Plantagineae clades of that family. Also, in Sibthorpia repens, we observe a possible transition from the colpate type to the porate type typical for taxa of Plantago and Littorella.

Dynamic changes in primexine during the tetrad stage of pollen development.

Formation of pollen wall exine is preceded by the development of several transient layers of extracellular materials deposited on the surface of developing pollen grains. One such layer is primexine (PE), a thin, ephemeral structure that is present only for a short period of time and is difficult to visualize and study. Recent genetic studies suggested that PE is a key factor in the formation of exine, making it critical to understand its composition and the dynamics of its formation. In this study, we used high-pressure frozen/freeze-substituted samples of developing Arabidopsis (Arabidopsis thaliana) pollen for a detailed transmission electron microscopy analysis of the PE ultrastructure throughout the tetrad stage of pollen development. We also analyzed anthers from wild-type Arabidopsis and three mutants defective in PE formation by immunofluorescence, carefully tracing several carbohydrate epitopes in PE and nearby anther tissues during the tetrad and the early free-microspore stages. Our analyses revealed likely sites where these carbohydrates are produced and showed that the distribution of these carbohydrates in PE changes significantly during the tetrad stage. We also identified tools for staging tetrads and demonstrate that components of PE undergo changes resembling phase separation. Our results indicate that PE behaves like a much more dynamic structure than has been previously appreciated and clearly show that Arabidopsis PE creates a scaffolding pattern for formation of reticulate exine.

Taxonomic studies in the genus Haplanthodes (Acanthaceae)

The endemic Indian genus Haplanthodes (Acanthaceae) is revised. Four species, viz. H. neilgherryensis, H. plumosa, H. tentaculata and H. verticillata and a new variety, H. neilgherryensis var. toranganensis are recognized. Lectotype is designated for Haplanthodes, Haplanthus plumosus and H. verticillaris. The nomenclature of the Linnaean name Ruellia tentaculata is also discussed. Micromorphology of seed using light microscope (LM) and scanning electron microscope (SEM) is observed for the first time, and two types, reticulate and micro papillate, have been recognized based on surface sculpturing pattern. The genus differs from the related genera Andrographis and Haplanthus by distinctly two grooved seeds with hygroscopic hairs. Pollen grains of the genus are oblate or prolate spheroidal, distinctly triangular, trizonocolporate with reticulate exine ornamentation.

English

The endemic taxa were restricted to a specific geographic region and they are essential for setting conservation priorities. This study aimed to update the endemic taxa list in Saint Katherine Protectorate (SKP) depending on literature reviews, field trips and herbaria consultation. Other characters also recorded viz, sex forms, dispersal types and flowering time. Also, the morphological characters of the pollen grains and seeds were examined and photographed using light microscope (LM) and scanning electron microscope (SEM). In addition, the mineral composition of pollens and seeds was detected using energy dispersive X-ray (EDX). The updated list included 13 taxa belonging to 11 genera and 8 families. All the recorded taxa were bisexual; ballochores were the most represented dispersal type. There was a gradual increase in the endemic taxa from March to August while decreasing from October to February. Pollens were isopolar and medium in size. They possessed colpate, colporate, or porate aperatus, as well as reticulate exine sculpture. Furthermore, operculum and margo were absent in most of the pollens. The seed colour ranged from light brown to black; elliptic; basal hilum; polygonal and irregular-shaped seeds were the most represented. All previous characters were diagnosed at generic and specific levels, which helped in the construction of artificial keys to facilitate the differentiation between the studied taxa. The present study has the priority in describing pollens and seeds of Astragalus fresenii and Micromeria serbaliana, in addition to the description of the seeds of Ballota kaiseri. The presence and percentage of twelve elements detected by EDX differed significantly within the investigated pollen grains and seeds. The present data indicated that pollen grains and seeds of studied taxa had high percentages of carbon, oxygen, phosphorous, magnesium, nitrogen and calcium. This study is the first attempt using EDX technique with these taxa. © 2021 Friends Science Publishers

Palynological characterization of the Southeast Asian woody climbers Decalobanthus Ooststr. (Convolvulaceae)

Decalobanthus is a genus of woody climbers of Convolvulaceae, recently expanded from a monotypic genus to including 17 species, mainly distributed in Asia and the Pacific. Despite the monophyly and the strong morphological and geographical coherence of the genus, only five of its species have been sampled in a molecular phylogenetic study and their relationships remain poorly understood. As a pillar to further systematic and evolutionary studies of Decalobanthus, this study offers a full characterisation of its pollen variation. To date, only seven of the 17 species have been palynologically documented in the literature (as Merremia s.l.). We here offer new data for seven species, which adding up to the already available data, totals a characterisation of 14 out of the 17 species in the genus. The pollen of Decalobanthus is, in most cases, tricolpate, with one species presenting hexapantocolpate polymorphism, which could suggest di/polyploidy; the presence of a reticulate exine (‘reticulum cristatum’ type) is remarkable, in Convolvulaceae only known otherwise in some species of Cuscuta.

Flora polínica da Área de Proteção Ambiental Serra Branca/Raso da Catarina, Jeremoabo, Bahia, Brasil – Família: Passifloraceae

Este estudo objetiva caracterizar morfologicamente grãos de pólen da família Passifloraceae, ocorrentes na Área de Proteção Ambiental (APA) Serra Branca/Raso da Catarina, Jeremoabo, Bahia, Brasil, visando complementar o levantamento palinológico e taxonômico realizado na área, bem como fornecer subsídios para o desenvolvimento do plano de manejo da APA Serra Branca/Raso da Catarina. Os botões florais foram coletados de material herborizado, depositado no Herbário HUNEB – Coleção Paulo Afonso. O material polinífero foi acetolisado, mensurado e descrito sob microscopia óptica e eletrônica de varredura (MEV). A família Passifloraceae está representada na Ecorregião Raso da Catarina por quatro espécies pertencentes ao gênero Passiflora: P. cincinnata Mast., P. foetida L. P. luetzelburgii Harms e P. setacea DC. Todas as espécies apresentaram grãos de pólen grandes, 6-sincolpados, aberturas aos pares, com três pontopérculos e três pseudopérculos, exina reticulada com a presença de báculos ou grânulos no interior dos grandes retículos sinuosos. Os resultados obtidos mostraram uma uniformidade morfopolínica caracterizando o gênero Passiflora na área de estudo como estenopolínico.

Pollen morphology and infrageneric classification of selected Callicarpa species (Lamiaceae) from the Philippines and Borneo

Abstract. Danila JS, Alejandro GJD. 2020. Pollen morphology and infrageneric classification of selected Callicarpa species (Lamiaceae) from the Philippines and Borneo. Biodiversitas 21: 5736-5746. We used pollen grains of ten species representing the controversial genera Geunsia Blume and Callicarpa L. from the key centers of Malesia - Philippines, and Borneo including other countries in Asia. Herbarium specimens and collected samples from the field were examined using Scanning Electron Microscopy (SEM) in search of new characters to establish conclusive evidence that might contribute to the study of the relationship between Geunsia and Callicarpa. Based on SEM observations, both the investigated pollen grains of Geunsia and Callicarpa are mostly small to medium, spheroidal or circular, prolate to oblate, isopolar, and tricolpate. Moreover, the exine surface is mostly coarsely reticulated with a thin perforated colpus edge and sunken finely granulated colpus membrane. However, exine ornamentation shows possible separation of Geunsia and Callicarpa due to various morphological results observed. Several types of exine ornamentation were found in species of the section Callicarpa, i.e., C. erioclona, C. arborea, C. macrophylla, and C. candicans which attributes in the projected separation of these species while four species in the section Geunsia are united as a group having coarsely reticulate exine. Surprisingly, C. arborea samples give additional support to the hypothesis that rugulate exine sculpture might be its plesiomorphic character due to evolutionary evidence of other exine types of this species. On the other hand, pollen size and shape class of the sections of Geunsia and Callicarpa were both observed with similar features having an average pollen size equivalent to medium and a prolate shape supporting the concept of previous studies to nest Geunsia within Callicarpa. This reveals that pollen morphology is useful in the study of infrageneric classification within these groups. However, further morphological studies involving larger number of specimens are needed especially in the study of exine to prove its consistency as diagnostic character in the study of phylogenetic relationship.

Quality assurance and authentication of herbal drug (Argyrolobium roseum and Viola stocksii) through comparative light and scanning electron microscopy

The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication.