Taxonomic implication of leaf epidermal anatomy of selected taxa of Scrophulariaceae from Pakistan

Taxonomic significance of anatomical and micro-morphological characteristics of Silene takesimensis Uyeki & Sakata

This study used the foliar epidermal anatomical characteristics through microscopic techniques to compare the foliar anatomy of Silene takesimensis Uyeki & Sakata (Caryophyllaceae). The species is endemic to South Korea. This study examined the foliar epidermal anatomical traits. The leaf morphological traits of the species are essential to distinguish the species from other taxa. The comparative systemic significance of the character species was examined. The epidermal cell shape, the epidermal cell wall, and the number of lobes per cell were among the distinctive foliar anatomical characteristics. The variations in quantitative characteristics were significant. The systematics of the genus Silene were supported by various microscopic methods. The foliar epidermal anatomical characteristics of the endemic species S. takesimensis have significant taxonomic characteristics to differentiate the species. RESEARCH HIGHLIGHTS: Silene takesimensis, a member of the Caryophyllaceae family, has been studied in-depth. Valuable insights and knowledge were obtained about the unique characteristics and behaviors of Silene takesimensis using SEM.

Foliar epidermal anatomical characteristics of Apiaceae species endemic to Ulleungdo and Dokdo Islands, Republic of Korea

The foliar epidermal anatomical characteristics of the two endemic Apiaceae species of Korea Bupleurum latissimum Nakai and Dystaenia takesimana (Nakai) Kitag. were investigated. The taxonomically important characteristics of these two species were identified and described to help understand their classical taxonomy. Scanning electron microscopy (SEM) was used to observe the anatomical characteristics of the studied species in detail. The comparative foliar epidermal anatomical characteristics were observed in the present research for the two-endemic species. Some of the most important foliar epidermal anatomical characteristics were observed to distinguish them, including the epidermal cell shape and size, stomata type, and trichomes shape and size. SEM provided sufficient evidence to distinguish the study species. The foliar epidermal anatomical characteristics provide sufficient information to differentiate these two species from their closely related taxa. RESEARCH HIGHLIGHTS: Apiaceae species endemic to Ulleungdo and Dokdo Islands exhibit unique foliar epidermal anatomical characteristics that can be used for taxonomic identification and classification. This study contributes to the documentation of the plant diversity of Ulleungdo and Dokdo Islands, and highlights the need for further research on the biogeography and conservation of these endemic plant species.

Micromorphology of the leaf surface in some species of Dryadoideae (Rosaceae)

The leaf surface of 5 species of the subfamily Dryadoideae (Rosaceae) was studied for the first time by cryoscanning electron microscopy. In the studied representatives of Dryadoideae, some signs of micromorphology were found that are characteristic of other Rosaceae. In Dryas drummondii and D. x suendermannii, cuticular folding was found on the cell surface of the adaxial leaf side. Stomatal dimorphism was found in Cercocarpus betuloides. A representative of the genus Cercocarpus had pronounced differences from the species of the genus Dryas in less pubescence of the abaxial surface with shorter and thicker trichomes, in small elongated stomata, and in smaller cells of the adaxial epidermis. Glandular trichomes and long multicellular outgrowths (possibly emergences) were found on veins in D. grandis. Structures resembling hydathodes or nectaries have also been noted on the leaf margin in this species.

Evaluation and identification of morphological characters suitable for delimitation of Taraxacum species distributed in northeastern China

Taraxacum germplasm resources in northeastern China are not current and do not accurately reflect the actual distribution of the species. The objective of this study was to investigate the morphological traits of Taraxacum species distributed in northeastern China and identify those that will facilitate their classification in this region. Leaf, flower, and achene characteristics of 18 species were used for morphological classification. Scanning electron microscopy (SEM) was used to examine pollen morphology. Internal transcribed spacer (ITS) sequences were analyzed to determine sequence differences among the species and their utility in delimitation. Taxa were classified into groups based on their morphology. The ITS sequence analysis supported the taxon classification, but the genetic distances among the taxa did not reflect morphological differences. Phylogenetic analysis was used to divide the 18 species into three groups. Group I: T. coreanum (which has white flowers). Group Ⅱ: T. heterolepis, T. sinomongolicum, T. variegatum, T. asiaticum var. lonchophyllum, T. falcilobum, T. brassicaefolium, and T. erythropodium (outer involucre bracts, narrow membranous or nonmembranous). Group Ⅲ: T. formosanum, T. liaotungense, T. mongolicum, T. borealisinense, T. ohwianum, T. platypecidum, T. urbanum, T. antungense, T. asiaticum, and T. junpeianum (outer involucre bracts, broad membranous). The main taxonomic characteristics of Taraxacum floral organs and achene morphology.

Scanning electron microscopic identification of ten novel, non-edible oil seeds for bioenergy production

Biodiesel is a sustainable, inexpensive, and alternative energy source produced from vegetable oils and animal fats. Precise and authentic identification of oil yielding plant species is very crucial. Therefore, scanning electron microscopy (SEM) was employed in our current investigation to study micromorphological characteristics of ten novel oil yielding seeds for their reliable identification. Macromorphological characters of sample seeds were explored by light microscopy. Seed size varied from 16 to 6.2 mm in length and 18.4-4.5 mm in width. Seed shape varied from ovoid to cordial and color from beige to brown. Seed oil content ranged from 25% to 45% (w/w). Whereas free fatty acid (FFA) content of seed oil varied from 0.42 to 3.4 mg KOH/g. Biodiesel potential of Chamaerops humilis was found to be highest (98%) in all. Besides, ultra-structural observation of seeds demonstrated variation in surface sculpturing which varied from rugous, reticulate, perforate, striate, and webby. Periclinal wall arrangements varied from rough, ridged, depressed, thick and curved whereas, anticlinal walls pattern showed variation from wavy, smooth, raised, deep and depressed. It was ultimately concluded that Scanning electron microscopy could serve as an advanced tool representing hidden ultra-structural characters of seeds. It offers significant knowledge to researchers and local community for their accurate and genuine identification.

Foliar micromorphology of selected medicinal Lamiaceae taxa and their taxonomic implication using scanning electron microscopy

In this research, 25 medicinally used Lamiaceae species belonging to 20 genera have been studied and identified for the nine disorders. We used scanning electron microscopy (SEM) for qualitative and quantitative morphological character identification. The micromorphological characters observed here were important for distinguishing the studied taxa. The highest medicinal values were reported for Vitex negundo and Scutellaria baicalensis for all considered categories except urinary and otorhinolaryngology disorders. The foliar epidermal anatomical characteristics revealed that the micromorphological features of the Lamiaceae species provide taxonomically significant and accurate identification information to delimitate the family species. Moreover, we focused on both qualitative (epidermal cell shape, stomata type, stomatal pore shape, subsidiary cell shape, glandular trichomes, and non-glandular trichome shape) as well as quantitative features (epidermal cell size, stomata size, stomatal pore size, subsidiary cell size, and trichomes size). The trichomes diversity was different in most species' on adaxial and abaxial surfaces. In most species, anomocytic stomata were observed, but other types such as diacytic, paracytic, and tetracytic type stomata were also examined. The diverse pattern of anatomical characters suggests that the studied taxa provide insight evidence for the taxonomic observation of the Traditional Chinese Medicinal plants from the Lamiaceae. This work sets an avenue for future research and taxonomic exploration of medicinal flora through microscopic investigations.

Light and scanning electron microscopy observations on morphological diversity of Rosaceae stigma and its taxonomic significance

The stigma morphology can provide a reference for exploring plant systematics and pollination biology. In this study, we observed the stigma morphological characteristics of Rosaceae in Beijing urban area in detail using light microscopy and scanning electron microscopy. The stigma of Rosaceae is entire or bilobed and mostly baculate, crateriform, cristate, discoid, or flattened. The stigma surface may have irregular, strongly raised ridges; or flat without papillae; or composed of densely or loosely arranged papillary cells. Surface ornamentation includes fossulate, psilate, psilate-striate, rugulate, scabrate, striate, and striate-rugulate. There are similarities in stigma morphology among genera and differences in stigma morphology among species within genera. The stigma shape supports the view of molecular systematic classification, that is, the former subfamilies Maloideae, Prunoideae, and Spiraeoideae are grouped into subfamily Amygdaloideae.

The morphology of stigma of Asteraceae observed by scanning electron microscopy

The morphology of stigma has taxonomic values. To further explore the taxonomy of family Asteraceae, the morphological characteristics of stigma of 28 genera, 32 species, and two varieties in the family were observed using scanning electron microscopy. The results indicated that the stigma morphology of these Asteraceae plants could be divided into 10 types, of which eight are reported for the first time. The morphological characteristics of stigma support the close relationship between genera Aster and Erigeron and among genera Sonchus, Taraxacum, and Youngia. Our results enriched the stigma type diversity data and provided a morphological basis for the study of the phylogenetic evolution of Asteraceae.

SEM observations on the vegetative plant parts of Acantholimon riyatguelii Yıldırım (Plumbaginaceae), a local endemic restricted to gypsum habitats

Acantholimon riyatguelii Yıldırım is a local endemic restricted to gypsum habitats. SEM observation on roots, stems and leaves of A. riyatguelii presented detailed information of ultrastructural properties which described this species adaptations to specific conditions of gypsum habitats. This study showed that A. riyatguelii leaves which are amphistomatic exhibited strong xeromorphic adaptations reflecting numerous stomata, surface hairs, thick cuticle (∼10 µm) and advanced palisade. The xeromorphic stomata in the leaves of the A. riyatguelii growing in aridty areas are in the form of deep cavities under the epidermis. Mesophyll cells had a somewhat rounded shape and placed rather regularly in the mesophyll. Some crystal deposits were observed at stomata and inside the mesophyll cells. In the root, xylem was in the form of pentarch along with the phloem observed among the protoxylems and the periderm was ca. 100 µm thick. In the stem, the centre of the stem was filled with large xylem vessels and five bundles of phloem tissue distributed around the xylem. The ultrastructural properties of A. riyatguelii, a gypsophyte species, were given for the first time in this study at Turkey and revealed detailed descriptive ultrastructures which could serve as a source of information and reference. Finally, this study offers new and interesting avenues to interpret ultrastructural features that allow gypsophiles to tolerate drought and atypical mineral soils.

Micromorphological considerations on Alyssum nezaketiae Aytaç & H. Duman (Brassicaceae), endemic to gypsum habitats from Turkey: An electron microscopic study

Alyssum nezaketiae is a local endemic species in gypsum habitats of Çankırı province in Turkey. In this study, I used field collected specimens of A. nezaketiae in a scanning electron microscopy examination of vegetative and reproductive structures of A. nezaketiae. The objective of the study was to investigate the micromorphological properties that define the species and that represent its adaptation(s) to the extreme environmental conditions posed by gypsum habitats. The epidermis had one to two rows at transverse sections of leaf and stem. Cortex was composed six to eight rows parenchyma cells at stem. A number of adaptations to xeric habitats were observed, including: dense silvery lepidote hairs on leaves and stems, small leaves, stomata on the lower surfaces of the leaves occurring in stomatal crypts, intense lignification in the central cylinder of the stems, and bundles of sclerenchyma in the pith region of stems. These can be interpreted as gypsophytic characteristics associated with physiological drought. Micromorphological properties of plant parts are discussed in relation to environmental conditions and possible constraint factors occurring in these gypsum habitats. Furthermore, these micromorphological studies contribute important taxonomic characters that are needed to help identify a species whose habitat is under threat from a variety of human activities.