Pollen used to track structural and functional evolution in plants as well as to investigate the problems relative to plant classification. Pollen characters including ornamentation, shape, apertural pattern, pollen symmetry, colpus length, width, and margins used to detect the similarities and dissimilarities between genera and also species of the same genus. In this study pollen features of 20 monocot species belonging to 15 genera of the Amaryllidaceae, Asparagaceae, Iridaceae, Ixioliriaceae, Liliaceae, and Xanthorrhoeaceae were studied using scanning electron microscopy (SEM) and light microscopy (LM). In this study two species that is Zephyranthes citrina and Tulbaghia violacea were reported for the first time from Pakistan. Pollen grains were visualized with LM. Non-acetolyzed and acetolyzed pollen were examined using SEM. A taxonomic key was developed to highlight the variation in pollen features in order to make their systematic application for correct species identification.

Foliar epidermal features were based on the micromorphology of trichomes types, epidermal cells and stomatal complex. Even though each feature has its own limited taxonomic value but collectively these characteristics may be systematically important especially for the discrimination and identification of complex and problematic taxa. The systematics significance of nonglandular (NGTs) and glandular trichomes (GTs), stomatal complex and epidermal cells of Lamiaceous flora were analyzed by using the light microscopy (LM) and scanning electron microscopy (SEM). Variations on the observed epidermal appendages were divided into two basic types: glandular and nonglandular. GTs can be divided into subtypes: sessile capitate, subsessile capitate, and barrel and sunken. NGTs were also divided into subtypes: dendritic, stellate, conical, falcate, simple and 1–6 cells long having granulate and smooth surface ornamentation. NGTs were the most dominant features of both adaxial and abaxial surfaces of all observed taxa. Vitex negundo, Isodon rugosus, Colebrookea oppositifolia, and Marrubium vulgare could be demarked because of their twisted like appearance of NGTs at the abaxial surface. The Lamiaceae had both hypostomatic and amphistomatic leaf. Stomata were observed as diacytic, anisocytic, and anomocytic. Epidermal cells were found to be irregular, isodiametric, and rectangular. Based on these characters a taxonomic key was developed to delimit the closely related taxa. Distribution and morphology of the foliar epidermal trichomes through SEM highlight an important taxonomic tool used by the taxonomists as an aid to the correct identification of problematic Lamiaceae taxa.

The pollen morphology of some species of glamorous family Convolvulaceae from arid zones of Pakistan has been evaluated. The pollen grains were acetolyzed, measured, described qualitatively, and illustrated using Light microscopy and scanning electron microscopy (SEM). The examined species have differences in shape, size, polarity and exine ornamentation, confirming the eurypalynous character. The pollen types varies from psilate to echinate and colpi to tricolporate, tetracolporate and pantocolporate. Exine ornamentation was exposed as perforate, reticulate and echinate. Spine morphology and exine sculpture are vital for the distinction of species. Pollen fertility shows that selected plants species are well-known in the Arid Zone. A taxonomic key is prepared to use these variations in the identification of species. Statistical analysis by using the Software XLSTAT exhibited that some morphological features is the main characters in identification of the taxa. These studied taxa were separated from each other using cluster Analysis. Our results constructed on MVSP ver. 3.22 software analyses that show morphological explanation; thus, the results highlight the importance of pollen morphology in the identification and characterization of species of the family convolvulacae in arid zone.

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