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Leaf hair types in Polish selected taxa from Potentilla subsect. Collinae Juz., i.e. P. collina Wibel s.str., P. silesiaca Uechtr. P. thyrsiflora Hillsen ex Zimmeter, P. wimanniana Gilnther and Schummel, P. leucopolitana P.J. Milller and P. leucopolitana P.J. Milller x P. incana P. Graebner were studied. A total of five unicellular hair types could be distinguished, based on the structure of the hair: straight, involuted, crispate, curved and stellate. The occurrence of involuted, curved and stellate hairs was observed for the first time for the majority of investigated taxa. There is a variation in density, position, as well as in the number of arms of stellate hairs. Although they are difficult to see without a stereo microscope, these differences seem to be systematically important. The study of hair types on surfaces of leaves supports the opinion that P. collina s.lato is a hybrid between P. argentea L. s.la-to, P. tabernaemontani Ascherson and P. incana P. Gaertner. Hairs form consistent characters which are highly suited for systematic purposes. The key to Polish taxa based on leaf hair types is given as well.
Distribution of the Potentilla species in the northern part of the Landscape Park “Orle Gniazda” (Silesia-Cracow Upland). Fragmenta Floristica et Geobotanica Polonica 11(2): 263–270. Kraków. PL ISSN 1640-629X. ABSTRACT: The list of 26 taxa of the genus Potentilla found in the northern part of the Landscape Park “Orle Gniazda” (Silesia-Cracow Upland) on 192 localities, mainly in the years 1999–2002 and on the base of a date with literature, was presented. Among them seven rare species in this region: P. intermedia, P. leucopolitana, P. pusilla, P. recta, P. recta subsp. recta, P. thyrsiflora and P. wiemanniana. P. arenaria (25 localities) and P. tabernaemontani (36) are the most common species of the genus on this area.
The evergreen, semi-parasitic pine mistletoe, Viscum album ssp. austriacum (Wiesb.) Volmann, is one of the four subspecies of European mistletoe, Viscum album L. It is frequently encountered on Scots pine communities in Poland. Distribution of pine mistletoe in representative P. sylvestris stand from the central Poland was investigated. The host density and host size to the frequency of Viscum was verified. Within the studied area 46% out of 313 individuals of P. sylvestris trees were infected by mistletoe, among them 78% in low mistletoe infection, 17% in medium and 3% in high infection. Of 1171 infections recorded on pines, 97% were on branches, 4% on the host trunk. The mistletoe individuals had an aggregated pattern of spatial distribution which was mainly explained by the host size. Infected trees are larger than uninfected ones, on average, and within the infected tree population, trees with mistletoe had higher number of dead branches than trees with none infection. Parasitized trees were more prevalent in low-density stands than in high-density stands. Mistletoes occurred mainly on the outer brunches within trees crowns.
The differentiation of the subassociation Molinietum caeruleae cirsietosum rivularis into three variants: typicum, with Carex davalliana, and with Sanguisorba officinalis is presented. A list of new localities of 16 regionally rare species of vascular plants, e.g. Iris sibirica, Gladiolus imbricatus, Trollius europaeus, recorded in 1999–2001 in the north part of the Silesia province is published.
Leaf morphological and anatomical differences between two collection sites in central Poland were examined in tall buttercup Ranunculus acris. We hypothesized that the availability of soil moisture would affect leaf morphological and anatomical traits. The objective of this study was to examine the effect of soil moisture content on: leaf size, epidermal features and on a number of stomatal characteristics in populations of R. acris species. The plants were investigated at sites differing in soil moisture conditions (a dryer upper site and a wetter lower site). Relatively semi-dry and wet sites were identified by plant communities and soil moisture content. We found out that morphological and anatomical leaf traits of R. acris were significantly related to soil moisture content. Leaves from plants growing in the wet site were 26% smaller in size than those from the semi-dry site. The population with smaller leaf area had larger leaf perimeter and higher dissection index. The stomatal index of the leaves sampled in the semi-dry site was higher than that of the leaves sampled in the wet site. Greater leaf thickness in the semi-dry site was primarily the result of increased spongy parenchyma thickness. On the abaxial leaf surface epidermal cell density was significantly higher at the wet site implying more epidermal cells. On the adaxial leaf surface, however, epidermal cell density decreased when plants were exposed to the elevated soil moisture. The results may indicate that soil moisture content influences leaf anatomy and morphology of R. acris. Thus, all these leaf morphoanatomical traits provide a basis for R. acris to reduce water loss from leaves and to balance water use efficiency under reduced precipitation. The present study demonstrates that R. acris can maximize growth in habitats with a wide range of soil moisture availability and such information can be crucial for developing management strategies and predictive models of its spread.
In the present study we investigated the seasonal pattern of activity of antioxidant enzymes such as superoxide dismutase (SOD) catalase (CAT) ascorbate peroxidase (APX), guaiacol peroxidase (POD) and syringaldazine peroxidase (SPOD) as well as the total protein concentration in the European mistletoe (Viscum album L. subsp. album). We studied mistletoe leaves that grew on the selected tree species in different parts the city of Lodz, exposed to a greater or lesser extent to the nitrogen dioxide. Sampling campaigns were conducted during the growing season 2013 in early May (at the beginning of the growing season) and in November (at the end of the growing season). We showed considerable seasonal variations of antioxidant enzymatic activity and total protein concentrations for all the samples studied. The test parameters varied depending on the host plants exposition to pollution with nitrogen dioxide. The changes in enzymatic activity did not depend on the host plants. In mistletoe leaves greater changes of SOD activity and total protein concentration were observed in autumn. There is correlation between the level of nitrogen dioxide in atmosphere and activities the enzymes. SOD activity was signifi cantly higher in autumn when the host plants were defoliated. Increased CAT activity was observed in late spring. We demonstrated the positive correlation between changes in enzyme activities and the progress of growing season. Increased activities of POD, CAT and APX to a limited extent depended on the place of growing and exposition to air pollution. In late spring activity of the enzymes did not signifi cant grow because of the protective umbrella from host plant leaves preventing the access of nitrogen dioxide to mistletoe. The higher SOD activity in mistletoe is a consequence of oxidative stress causes by nitrogen dioxides evidently observed in the city center. The test parameters, mainly the activity of SOD, can be used in the future as markers of the environment purity, especially in the autumn and winter when the temperatures are above freezing, and there are no leaves on the trees.
Germination responses of Galium cracoviense Ehrend. (Rubiaceae), a narrow endemic species from southern Poland, were tested in light and dark conditions at three constant temperatures (5, 10, or 22°C), before and after cold-wet stratification. Additionally, seeds were germinated under different calcium carbonate (CaCO3) concentrations (1, 5, 10, 15, 20, or 25 mM/L CaCO3) at 22°C in light. The high germination capacity of seeds incubated at different temperatures, shortly after collection, already suggested the absence of dormancy in this species. Thus, the seeds are ready to germinate immediately in the field when water resources are available and the temperature is adequate. Light was a significant factor for G. cracoviense; more seeds germinated in light than in darkness at all temperatures tested. Cold stratification decreased germination especially at higher temperatures. The light requirement for G. cracoviense germination ensures their successful germination on or near the soil surface, and in cracks and crevices in limestone, when temperature and edaphic conditions are favourable. Seeds of this species show temperature enforced dormancy throughout the winter. Germination was significantly affected by calcium carbonate. Non-germinated seeds germinated well after being transferred from higher CaCO3 concentrations to distilled water. The results indicate that the seeds of this species can endure CaCO3 stress without losing their viability and start germination once CaCO3 concentration is reduced. It can be concluded that the seeds of this species require lower Ca2+ ion concentration, moderate temperatures and the presence of light to germinate.
Achenes morphology in taxa from Potentilla collina s.l. i.e., P. collina Wibel s.s., P. leucopolitana P.J. Müller, P. thyrsiflora Hülsen ex Zimmet., P. thyrsiflora var. isosepala Th. W., P. silesiaca Uechtr. And P. wimanniana Günther and Schummel was examined with stereoscope and scanning electron microscopy. Achenes of these taxa varied slightly in shape, size and colour, while marked differences among them appeared in the surface sculpture and in the dimensions of aril, dorsal ridge and ribs. SEM analyses allowed to distinguish two distinct morphological types of achenes. Type I - with ruminate sculpture and aggregates of some material, various in shape and size, at the surface of partly destroyed epidermal cells covering fruit wall in P. leucopolitana, P. wimanniana and P. thyrsiflora. Type II - with ruminate-reticulate sculpture due to well preserved epidermal cells in P. silesiaca and P. thyrsiflora var. isosepala. The obtained results have supported Błocki’s suggestion to treat P. thyrsiflora var. isosepala as a separate species named P. isosepala. However, similarities in the surface sculpture of achenes in some taxa of P. collina group did not facilitate their classification, therefore this feature may be a valuable taxonomical criterium only in combination with others.
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