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EN
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.
EN
Pollen grains of Cunninghamia lanceolata, Cryptomeria japonica and Sciadopitys verticillata were examined by light and scanning electron microscopy. The pollen grains were non-saccate, generally oblate-spheroidal, spheroidal, prolate-spheroidal or subprolate. The pollen grains had papillae of different sizes and shapes on the distal face. The papillae were more conspicuous in C. japonica than in C. lanceolata. The pollen exine sculpture in the proximal view was verrucate-granulate and verrcucate with microechinate suprasculpture in SEM. The surface of the exine was covered with echinate orbicules in Cupressaceae species. There were some differences in the size of the verrucae, perforation on the proximal surface and distal face between S. verticillata pollen grains and other species. This study of the pollen grain morphology provided some important new data which have not been reported in literature so far.
EN
The article presents the composition of the dendroflora in a historic park surrounding the castle in Szamotuły. In total 465 specimens of woody plants were inventoried (51 taxa of 37 species in 21 families). Most of them were native, angiospermous trees of the apophyte and spontaneophyte groups. In the park there are three specimens of Taxus baccata, registered as natural monuments. The age of more than 100 trees was estimated at over 100 years. The trunk circumference of more than 60 trees exceeded the minimum value assumed as a criterion of categorisation as a natural monument.
EN
Pollen grains of Pinus uliginosa and P. uncinata 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 with or without 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. Among the P. uncinata from the Forest Arboretum there were differences observed in the size, shape and height of elevation and sculpture on the corpus between pollen grains of the same specimen. This study of the pollen grain morphology of the corpus and saccus provided some important new data.
EN
In the period from September 2008 to July 2009 in the Grunwald district in the city of Poznań, Poland, a total of 609 localities of flowering English ivy were recorded, for which 769 plants were described. These plants were found in different localities, most of them euhemerobic. The biggest number of flowering specimens was recorded in home gardens. Support for climbing plants was mainly provided by trees and shrubs, including fruit trees – pear and apple trees. Among the other tree species, the biggest group comprises Scots pine, common birch, European larch and common locust. Other types of supports included fences, buildings and elements of small architecture. A very high number of specimens in the generative stage in the Grunwald district indicates considerable popularity and at the same time very good adaptation of ivy not only to the climatic conditions of the city of Poznań, but also to anthropogenic changes in the habitat.
EN
The present study was conducted to illustrate the micromorphology of mature sporangia and pollen grains of four Ginkgo biloba cultivars: ‘Horizontalis’, ‘Lasiocarpa’, ‘Pragensis’ and ‘Tubifolia’ and is a continuation of earlier investigations on this subject. The sporophylls bear typically two pendulous sporangia, whereas three were found in one cultivar. The sporangia varied in shape from oval, elliptical elongate to boat-shaped and dehisced along a longitudinal slit. The sporangial walls are multilayered. The sculpture of the sporangium is rugose covered with wax crystals (tubules) and the endothecium shows clearly visible fibrous thickening on the wall. The pollen grains are monosulcate, the non-apertural surface is irregularly ridged (striate) or rugulate, with perforations and the germinal aperture (furrow) is covered with verrucae. The current study did not differentiate significantly four cultivars based on sporangia and pollen morphology. The micromorphological traits may be useful for identification and classification of fragments of fossil sporangia and pollen grains.
EN
The article presents the results of research on the morphology and anatomy of the leaves of 21 cultivars (including 10 Polish cultivars) and two clones of Ginkgo biloba. Leaves from long shoots were collected at the Department of Dendrology and Nursery, Poznań University of Life Sciences, Poland. A light microscope and scanning electron microscope were used for observations. Eight morphological traits were analysed in the leaves, including the lamina and petiole. The research revealed that there were significant differences between the leaves of individual cultivars and that they differed in the length, width of the lamina and the length of petioles to a much greater extent than publications had described it so far. There were significant differences between the adaxial and abaxial epidermis of all the taxa, i.e. in the cuticle ornamentation, in the protrusive secondary sculpture (absence of papillae), the position and presence of stomata (occasionally on the adaxial leaf surface), the absence of the peristomatal ring and the thickness of the epidermis. Anatomical investigations revealed that the leaves of Ginkgo cultivars and clones under study were bifacial and the multi-layered mesophyll was diversified into spongy and palisade parenchyma. The research findings may be used for the identification of Ginkgo biloba cultivars, and the epicuticular traits may be useful for the identification and classification of fragments of fossil leaves. The article includes descriptions and illustrations of several new quantitative and qualitative characters of petiole and lamina which have not been published previously.
PL
W pracy przedstawiono wyniki badań nad morfologią i anatomią liści 21 odmian (w tym 10 polskiej hodowli) oraz dwóch klonów Ginkgo biloba. Liście z długopędów pochodziły z kolekcji Katedry Dendrologii i Szkółkarstwa Uniwersytetu Przyrodniczego w Poznaniu. Obserwacje prowadzono przy użyciu mikroskopu świetlnego i skaningowego. Liście analizowano pod względem 8 cech morfologicznych, uwzględniając blaszkę liściową i ogonek liściowy. Na podstawie tych badań stwierdzono, że liście poszczególnych odmian różnią się istotnie między sobą i wykazują większe zróżnicowanie w długości, szerokości blaszki liściowej i w długości ogonków niż dotychczas opisywano w literaturze. Cechy epidermy górnej i dolnej wszystkich taksonów różnią się istotnie, m.in. ornamentacją kutykuli, brakiem brodawek, położeniem i występowaniem szparek (sporadycznie na górnej powierzchni liścia), brakiem pierścienia wokółszparkowego i grubością epidermy. Na podstawie badań anatomicznych stwierdzono, że liście odmian i klonów miłorzębu są bifacjalne oraz mają zróżnicowany miękisz zieleniowy na palisadowy i gąbczasty. Prezentowane wyniki badań zmienności cech morfologicznych i anatomicznych mogą być wykorzystane w identyfikacji odmian G. biloba, a cechy epikutikularne przydatne w identyfikacji i klasyfikacji fragmentów liści kopalnych. Kilka cech opisanych i zilustrowanych w pracy jest nowych, dotychczas niepodawanych w literaturze.
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