A comparative anatomical study of the Plectranthus species growing in Saudi Arabia by using light microscopy method in order to evaluate their diagnostic value for systematic studies. Macro- and micromorphological characters, including stem, leaf, petiole anatomical, and trichome structures are presented. Descriptions of stem shape in cross-section, epidermal cell shape, cortex, pith, vascular bundles, leaf shape in cross-section, mesophyll, types and distribution of trichomes are presented. Taxonomic phylogenetic implications of stem, leaf, and trichomes anatomical micromorphology are also discussed in comparison with the available gross morphological and molecular data. Results of the present study offer useful data for evaluating the taxonomy of Plectranthus both at subgeneric and sectional levels. Moreover, our results indicate some degree of similarity among the species of subgenus Germanea and support the monophyly of this subgenus. A remarkable result from this study was identifying P. arabicus with distinctive characters and suggesting that it should be treated as a separate subgenus. Likewise, distinguishing differences between closely related endemic species P. asirensis and P. hijazensis are offered, and should be conserved as a different subgenus. A key for the identification of the investigated taxa based on studied characters is provided. Microsc. Res. Tech. 79:583-594, 2016. © 2016 Wiley Periodicals, Inc.

No abstract

I N THIS study, we evaluated the storage proteins, macro-and micromorphological characters of seeds from 49 species belonging to 34 genera and seven subfamilies of the Malvaceae s.l. (i.e, Malvaceae s.s., Bombacaceae, Sterculiaceae, and Tiliaceae) along with one representative of the Elaeocarpaceae as an outgroup. We obtained microphotographs of the specimens using both light and scanning electron microscopes. The seed storage protein was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). We analyzed 73 recorded characters (with 157 characters-states) were analyzed using the upgraded WinClada and TNT cladistic programs. A cladogram was constructed which indicated a clear indication about the systematic position between the studied species within the Malvaceae s.l. The results showed specific synapomorphic diagnostic characters are quite significant in species delimitation within the Malvaceae s.l. viz., including seed shape, apex, base, colour, size, texture, hilum shape, position, seed coat sculpture patterns, and occurrence of strophioly. Our results also support the monophyly of the studied genera in Malvioideae except for Gossypium and Thespesia, while para-polyphyly in the other six subfamilies.

No abstract

anatomical characters of spermoderm of certain species of Resedaceae and their contribution to the taxonomy of the family. Taeckholmia 22(2):155-176. The morphological and anatomical characters of the spermoderm of 27 species of Resedaceae were examined and described to assess the applicability of these attributes in the process of identification. Many of the recorded morphological and anatomical attributes were found to be fairly diagnostic at both the generic and specific levels. Unlike earlier claims that Reseda alba and R. decursiva are conspecific; the present data justify their treatment as distinct species. A correlation was found between some of the studied characters.