Taxonomic significance of foliar epidermal morphology in Lamiaceae from Pakistan

Foliar micromorphological features are useful to elucidate the taxonomy and systematics of the Lamiaceae species. Leaf epidermal morphology using scanning electron microscopy and light microscopy of 22 Lamiaceae species from 15 genera have been investigated with an aim to solve its taxonomic problem in the correct identification. Various foliar micromorphological features were observed to explain their importance in resolving the correct identification of Lamiaceae taxa. Two main types of trichomes were observed; glandular trichomes (GTs) and nonglandular trichomes (NGTs). GTs were further divided into seven subtypes including the capitate, subsessile capitate, sessile capitate, sunken, barrel, peltate, and clavate. Similarly, NGTs were also divided into simple unicellular and multicellular including conical, falcate, cylindrical, dendrite, papillose, and short hook shape. Quantitative measurement includes the length and width of the trichomes, stomatal complex, epidermal cells, stomata, and trichomes index. Based on the foliar micromorphological characters, a taxonomic key was developed to delimit and correctly identify studied taxa. Further molecular, other anatomical and phylogenetic studies are recommended to strengthen the systematics of Lamiaceae.     

Comparative anatomy on the vegetative organs of genus Ziziphora L. (Lamiaceae) from Turkey

The genus Ziziphora L. (Lamiaceae) is represented by five species (nine taxa) in the Turkish Flora. These taxa are Z. clinopodioides Lam. (subsp. elbursensis, subsp. filicaulis, subsp. kurdica, subsp. rigida), Z. capitata L., Z. persica Bunge, Z. tenuior L., Z. taurica Bieb. subsp. taurica, and Z. taurica Bieb. subsp. cleonioides (Boiss.) Davis which to be an endemic taxon for Turkey. They are strongly aromatic herbs which contain rich pulegone and used as herbal teas and spices and for this reason. In this study, comparative anatomy of the genus Ziziphora growing in Turkey is presented for the first time. In anatomical studies, cross sections of vegetative organs such as the root, stem, and leaf (lamina and petiole) were examined. In addition, to exhibit stomatal distribution and anatomy on adaxial and abaxial leaves were taken surface sections of the lamina and calculated stomatal index. Lamina and petiole anatomy were shown to be of great importance in the taxonomy of the Ziziphora taxa. The presence or absence of sclerenchyma in midrib of lamina and petiole, cortex parenchyma layer, mesophyll structure, and epidermal surface were found to be important characters for identification of Ziziphora taxa.     

Leaf epidermal characteristics of Cissampelos L. (Menispermaceae) species from Northeastern Brazil

The morphological similarities among the species of Cissampelos are remarkable and the difficult to distinguish them as well. This article presents a comparative anatomical study of the leaves of common Northeastern Brazilian species of Cissampelos, carried out using light and scanning electron microscopy. The leaf epidermal was studied to obtain data on epidermal characteristics and to evaluate their taxonomic significance. As results, some micromorphological characters on the leaf epidermal like the cuticular waxes, the presence of papillae in epidermis and nonglandular trichomes, the anticlinal walls epidermal cells, the distribution, density and type of trichomes, and also the type and distribution of epicuticular wax proved to be the most useful characteristics to distinguish the species in taxonomic studies. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.     

Pappus and fruit micromorphology and fruit anatomy in some members of the tribe Cardueae (Asteraceae) from Turkey with their contributions to systematics

The present investigation aims to determine pappus and fruit characters of 21 taxa representing 12 different genera from Turkey. For this reason, present data of pappus and cypsela characters as well as previous results from 21 additional Cardueae taxa have been comparatively evaluated, and a total of 42 taxa were grouped by using cluster and MDS analysis methods. The cluster analysis resolved two main clusters, with five taxa having scale or coroniform pappus as the first-branching group. Considerable variations were observed in the surface sculpture, and the pericarp and testa anatomical structures as well as the pappus characteristics. On the basis of fruit surface sculpture, four major types and two subtypes of ornamentation patterns were discerned, and based on their anatomies three types of testa epidermal structure were recognized. Our results show that Centaurea s.l. taxa do not exhibit clear distinction from the genus level; in some cases the taxa are separated to some extent, in other cases they are combined with Cyanus and Psephellus taxa. Two Klasea species with sclerenchymatous mesocarp exhibit the closest relationship to Centaurea s.l. taxa. Rhaponticum repens displays the nearest neighborhood with Centaurea s.l. and Klasea taxa. A diagnostic key based on the examined characteristics has been given. The taxonomic importance and systematic implications of the results are discussed in the light of the current framework. The evaluated cypsela and pappus characters are useful not only in assessing relationships within this group but also in delimiting genera and species.     

Pollen morphology of Aletris L. (Nartheciaceae) and its systematic significance

In this paper, we studied pollen morphologies of seven species in genus Aletris in detail by light microscopy and scanning electron microscopy. Of these, six species were reported for the first time. The palynological characteristics do not support the infrageneric classification into two clades. The results indicated that pollen grains of Aletris are small or medium with the P/E ratio of 0.36–0.59. They are elliptic or long‐elliptic in the polar view with blunt, round or acute ends and bilateral symmetric with a monosulcate, narrow or wide, deep colpus that has length extending to the ends of pollen grains, obvious or absent colpus membranes. The pollen ornamentation is gemmate, perforated, or reticulate. The sexine is slightly or quite thicker than the nexine.     

Microscopic and phytochemical techniques as a tool for authentication of herbal drug chiraita: Swertia cordata (G. Don) C.B. Clarke

Swertia cordata (G. Don) C.B. Clarke is one of the potential medicinal plants extensively used in eastern traditional medicine such as Unani, Ayurveda, Siddha, and in traditional Tibetan and Chinese medicine. S. paniculata is the common adulterant of S. cordata at herbal shops and markets but S. paniculata is also used in number of herbal formulations. The present study was conducted to use microscopic, pharmacognostic, and phytochemical techniques as a tool for the authentication of herbal drug chiraita (S. cordata). In herbal markets, mixing, adulteration, and use of spurious materials as substitute have become a major concern for herbal practitioners, local user, and industry for reasons of safety and efficacy. Therefore, authentication of medicinal plants is of utmost importance at each level of drug research. In the present study, anatomical features of two species showed a great diversity, as irregular epidermal cells and nonglandular, unicellular trichomes were found in S. cordata while in S. paniculata epidermal cells were hexagonal in shape and trichomes were A‐shaped. Antioxidant activity of two species showed a great variation where IC₅₀ value recorded for S. cordata was 208 μg/mL, while for S. paniculata IC₅₀ was 624 μg/mL. The study can serve as an important source of information to achieve the authenticity and to evaluate the quality and purity of the plant material in accordance to WHO guidelines. As this species is greatly exploited, so conservation is highly recommended.