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The pollen morphology, with special reference to exine sculpture, of some species of the gymnosperms was assessed for the first time from the subalpine and alpine zones of western Himalayas northern Pakistan. The pollen of all these species is airborne and allergenic, so pollen morphology helps for identification of this allergenic pollen at specific level. Different morpho‐palynological characteristics were analyzed including size range of pollen, polar and equatorial diameter ratio, exine ornamentation, sculpturing, exine thickness, pollen type, and shape. For accurate and quick identification of species, taxonomic key was made based on different morpho‐palynological characteristics. The quantitative data were processed using SPSS software. Gymnospermal pollen includes inaperturate, rarely 1‐colpate observed in (Cupressaceae), hexazonocolpate in (Ephedraceae), vesiculate, bissacate in (Pinaceae), and inaperturate in (Taxaceae). Different pollen shapes observed were prolate (4 spp), sub‐spheroidal (7 spp), and oblate (1 spp). Variation was observed in exine sculpturing granular (4 spp), reticulate (1 spp), areolate‐punctate (3 spp), and psilate (2 spp). This is based on the analysis of 10 plants belonging to four families of gymnosperms. Distinct pollen shape has emerged as the most diagnostic feature to separate some genera such as spheroidal in (Cupressaceae, Taxaceae), prolate and radiosymmetrical in (Ephedraceae), and bilateral in (Pinaceae). Exine thickness and sculpturing proved to be helpful at generic and specific levels. The results reinforced the significance of gymnospermal pollen morphological features which were used as aid for valuable taxonomic tool in plant systematics. [ABSTRACT FROM AUTHOR]

Leaf epidermal anatomy of tribe Trifolieae L. has been studied with the objective to assess the characteristics that can be used to reevaluate the circumscription and systematic position of tribe. Using light and scanning electron microscopy, leaf epidermal characters of 17 species belonging to four genera of Trifolieae (Medicago L., Melilotus Mill., Trifolium L. and Trigonella L.) are investigated. The placement of Melilotus and Trigonella in one section Grammocarpus was also reassessed on the basis of leaf epidermal characters. Presence of characteristic anomocytic stomata with great variation of size and short, unbranched, unicellular, non glandular trichomes with acute apex are diagnostic characters for delimitation of species in Trifolieae. The distributional density of trichomes varies greatly between genera and found to be highest in genus Medicago. The value of stomatal index ranges between 24.6% (Trifolium dubium) to 83% (Trigonella foeno graceum). In general, present study concludes that the variations of all traits are mostly sustained and intrinsic to the species and of promising taxonomic value. The combination of leaf epidermal characters in correlation with other traits has potential for taxonomic resolution at species level. Further phylogenetic studies on tribe, based on more comprehensive sampling will probably explain intrageneric relationships in Trifolieae. [ABSTRACT FROM AUTHOR]