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The aim of presented experiments was to determine the usefulness of plant extracts for dressing of cereal seeds. Water extracts (macerations, infusions) prepared from different morphological parts of 39 plant species were used as dressing preparations. Non-disinfected seeds of two cultivars of barley (Hordeum vulgare L.): Rudzik (brewing barley) and Stratus (common barley) were used for the purpose of dressing. The experiment was conducted as a filter paper test (PN-94 R-65950) while determining the germination viability (1st date) and the germination capacity (2nd date) as well as the healthiness of the seeds. A significant differentiation of the effect of the extracts on vitality and healthiness of seeds was demonstrated depending on the origin of the extract (plant species), the way it was prepared and an interaction between these factors. The germination viability of seeds of brewing barley was influenced mostly by infusions from fruits of Coriandrum sativum, from seeds of Linum usitatissimum, from bark of Quercus robur, from roots of Levisticum officinale, from roots of Arctium lappa and from flowers of Verbascum thapsiforme. The most favourable activity on germination capacity was revealed using the infusions from seeds of L. usitatissimum, from roots of A. lappa, from fruits of C. sativum and macerations from roots of A. lappa, from fruits of C. sativum and from bark of Q. robur. The infestation of seeds by microflora was reduced by macerations from leaves of Betula verrucosa, from seeds of L. usitatissimum, from fruits of Juniperus communis, and infusions from flowers of Crataegus oxyacantha, from seeds of L. usitatissimum, from leaves of B. verrucosa. The most favourable impact on viability of the seeds of common barley was revealed for infusions from roots of L. officinale, from stigmas of Zea mays, from flowers of C. oxyacantha and macerations from flowers of Lavandula vera, from leaves of Mentha piperita and from roots of L. officinale. A positive effect on the germination capacity was exerted by infusions from the stigmas of Z. mays, from flowers of C. oxyacantha, from rhizomes of Acorus calamus, from bark of Frangula alnus, and macerations from bark of F. alnus, from leaves of M. piperita, from flowers of C. oxyacantha and from herb of Marrubium vulgare. The contamination of the seeds by microflora was reduced most effectively with infusions from young sprouts of Pinus sylvestris, from roots of Inula helenium, from leaves of Juglans regia, from herb of M. vulgare, from stigmas of Z. mays and macerations from rhizomes of A. calamus, from herb of M. vulgare, from leaves of J. regia, from seeds of L. usitatissimum and from flowers of L. vera.
Regular physical activity positively affects the entire organism and also the vitality of the human body. The aim of our study was to analyse the attitude of recreational swimmers to other sports activities. The research group involved 55 participants from Košice (35 men aged 34±11,7 and 20 women aged 33±10,7). As a research method, we used a questionnaire with mostly closed questions. The answers of recreational swimmers suggest a positive finding that recreational swimming inspires them to practice also other sports activities. Most of the recreational swimmers practice other sports activities that are not organized but they do other sports activity 1–5 times per week. The men prefer and practice more sports activities per week than women (p <0,05). The participants mostly practice cycling, running, men also play football and hockey, wheres women practice fitness and dance. Most of the participants would like to do more activities but they are limited by lack of free time and specifically women are limited by family care (p <0,05). All the participants practice other sports activities because of their own need, whilst women chose to maintain appropriate body weight and good figure as the significant reasons for practicing the sports activity. In general, we can conclude that recreational swimmers, who practice swimming 1–2 times per week and also practice 1–5 times per week other sports activities, have enough physical activity positively influencing their health and physical condition.
Taxus baccata is a rare species throughout its entire natural range and is often categorized as nationally threatened in countries where it occurs. In Poland yew is under protection and almost all sites with yew occurrences are subject to reserve protection. The aim of the study was to answer the following questions: What is the tree diameter structure of stands in three yew reserves? What is the stand biodiversity of three yew reserves in central Poland? How does the stand species composition influence natural regeneration of yew? What shall be done in the future to protect yew in its natural habitats? The study was conducted in three yew reserves in central Poland. Based on a detailed research on 30 circular sample plots established in each reserve we found high stand diversity in all investigated areas. Shannon-Weiner index (H´) was high in general and ranged from 1.50 to 1.69, and the Shannon's index of evenness (E) ranged from 0.51 to 0.64. The diameter structure of two studied reserves was similar to natural multi-layered stand structure. The number of yew trees and their vitality was low. The species diversity of natural regeneration in all reserves was very high. However, the quantity and quality of yew regeneration in multi-layered diameter structure was significantly lower than in one-layered stand structure. To protect yew, appropriate conservation measures should be undertaken, including silvicultural treatments for in situ species conservation. We found that passive conservation is an inappropriate strategy for yew because of its weak competitiveness ability. We recommend active conservation approach, including silvicultural treatments. i.e. cutting broadleaved trees in places where the basal area is the highest, removing some trees in the upper layer of stand which compete with yews. Individual protection of yew seedlings and saplings is also necessary because of damages caused by herbivores.
The European beech is a major component of central European forests, and the eastern limit of its range lies in Poland. However, the Holocene migration of the beech is not yet finished, especially in NE Poland, so the northern distribution of the beech continues to change. The main goal of this study was to determine if the beech will reach its northern limit in the future. The investigation was carried out in 18 beech stands in Poland. To study the status of the health of the trees, circular plots were established in grids of different sizes. The basal beech stand area ranged from 3.7 m² ha⁻¹ to 31.2 m² ha⁻¹. The density of trees exceeded a hundred trees per hectare in most of the plots (61%), and the average degree of defoliation was not greater than 60% in all of the investigated stands. Environmental conditions influenced defoliation of beech trees (Fisher's test, F = 4.0204; P <0.0001). The vitality of the beech trees varied between stands (Kruskal-Walis test, H = 139.7433, P <0.0001) and was rather good in 56% of the study plots. Seedlings and saplings were observed in all of the investigated stands, and they covered from 5 to 39% and 21 to 80% of the study plots, respectively. Spontaneous beech regeneration was widespread and differed from stand to stand as well as within stands in all of the study plots. The number of tall seedlings in most of the study plots (56%) was greater than 10,000 individuals per hectare. The factors limiting beech regeneration were stand density and herb cover, and the number of beech seed trees influenced the quantity of small seedlings. Beech tree density positively influenced the number of small seedlings, and the strength of the correlation was moderate and statistically significant (Pearson correlation, r = 0.349). Beech tree density influenced the vitality of tall and small saplings (Pearson's correlations, r = 0.673 and r = 0.361, respectively). The spontaneous regeneration and strong vitality of seedlings and saplings suggests that beech can create stable stands in the future and that it is an expansive tree species both within its continuous range and at the limit of its distribution. It is quite possible that beech will reach its north-eastern limit in Poland in the future.
The present study examines the mechanism of natural and accelerated ageing processes in Norway spruce (Picea abies [L.] Karst.) seeds stored at low temperature for one (control) and eight years. The analyses of vitality, electrolyte leakage, protein composition and activity of the proton-pump ATPase (P-ATPase, EC.3.6.1.35) in plasma membrane of Norway spruce seeds have been investigated. Seeds collected in 1999 from northeastern Poland have been treated with accelerated ageing method and compared to the seeds of the same provenance, collected in 1992 (control). The vigor and the vitality of the Norway spruce seeds depend on the age of seeds. After 6 days of experiment both samples of seeds (artificially aged seeds and control) expressed the same percentage of germination and similar electrolyte leakage. Analysis of protein composition in the extracts showed an increased amount of some low molecular-weight proteins in artificially and naturally aged seeds compared to the control. Our results indicate similar level of P-ATPase activity in natural, artificially aged and control seeds. This suggests that natural ageing process can involve changes in plasma membrane protein composition but does not affect the P-ATPase activity.
The viability of zebra mussel (Dreissena polymorpha) sperm and changes in the integrity of its plasma membrane were examined using combined nucleic fluorescent stains SYBR-14 and propidium iodide. Approximately 97 ± 3% of the sperm in freshly ejaculated zebra mussel semen was stained with SYBR-14 (potentially viable). A statistically significant decrease in plasma membrane integrity was observed after 48 hours (8°C) when 42 ± 11% of the sperm stained as viable. Semen stored at room temperature (20°C) lost its plasma membrane integrity after 4 hours (0% viable). Motility declined from 60 ± 4% (0 time) to 30 ± 3% after 24 hours. The percentage of sperm stained with SYBR-14 was not correlated with sperm motility or the fertility test.
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