Abstract Pollen grains of Pinus mugo, P. sylvestris and P. ×rhaetica (= P. mugo × P. sylvestris) were examined by light and scanning electron microscopy. The pollen grains were bisaccate and monosulcate. The corpus-saccus attachment was distinct. The pollen corpus exine sculpture was verrucate-rugulate and deeply sculptured. The surface of the tectum was covered with small grana and it was perforate. The saccus sexine ornamentation was reticulate and irregularly perforate. The tectum surface characters in the proximal and distal view of the corpus and saccus were less variable and they did not provide good criteria to identify the species under study. However, some differences were observed in the size of elevation on the corpus between pollen grains of the same species and between the parental species. This study of the pollen grain morphology of the corpus and saccus provided some important new data.

This study is the first comparison of the morphology of pollen grains in ten cultivars of three species of the Taxus,

Torreya nucifera and Cephalotaxus harringtonia var. drupacea genera. The material came from the Botanical

Garden of Adam Mickiewicz University in Poznań, Poland. Each measurement sample consisted of 50 pollen

grains. In total, 750 pollen grains were analyzed. Light and electron scanning microscopy was used for the morphometric

observation and analysis of pollen grains. The pollen grains were inaperturate and classified as small

and medium-sized. They were prolate-spheroidal, subprolate to prolate in shape. The surface of the exine was

microverrucate-orbiculate, perforate in Cephalotaxus harringtonia var. drupacea, granulate-orbiculate, perforate

in all Taxus taxa and granulate-microverrucate-orbiculate, perforate in Torreya. The orbicules were rounded to

oval in surface view, and the size was considerably diversified. The pollen features were insufficient to distinguish

between individual Taxus members – only groups were identified. The values of the coefficient of variability of

three features (LA, SA and LA/SA) were significantly lower than the orbicule diameter. The pollen surface of all

Taxus specimens was similar, so it was not a good identification criterion. The pollen grains of the Taxus taxa

were smaller and had more orbicules than Cephalotaxus and Torreya. Palynological studies provided taxonomic

support for recognition of two different genera of the Cephalotaxaceae and Taxaceae families, which are closely

related.

Abstract Pollen grains of 15 species of the genus Sansevieria were examined using light and scanning electron microscopy. The pollen grains were single, but dyads were also found. The basic shape of the pollen grains (with chemical treatment) was subprolate, prolate and prolate-spheroidal and the pollen grains were large (> 50 mm). The pollen grains observed in SEM were prolate-spheroidal, subprolate, prolate and perprolate. The aperture occupied nearly the entire distal hemisphere. The surface of non-apertural areas was microreticulate, psilate-perforate, fossulate and verrucate. The surface of the apertural area was psilate-perforate-verrucate, microreticulate-verrucategemmate and psilate-perforate. The tectum was homogeneous, with perforations. Our results suggest that some species cannot be separated based on pollen grain morphology, but only may be categorized into their groups. The present study investigated pollen grain morphology in eleven species for the first time in terms of pollen micromorphology and provided some important new data.