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Blooming phenology and pollen production in the five Oenothera species were investigated during the period of 2013-2015 in the Lublin area, SE Poland. The blooming period was relatively long, and flowering usually started in the middle or late June and lasted until late July or the middle of August. The Oenothera species studied exhibited nocturnal anthesis, i.e., the flowers opened in the late evening and lasted overnight until the early morning hours. Plants developed a great number of flowers per individual and per unit area (on average, 158 and 4,136, respectively), and this feature appeared to be species-specific. It was demonstrated that the blooming phase had an impact on the mass of anthers and pollen produced per flower in all Oenothera species. In general, the greatest mass of anthers and pollen was observed at the beginning of blooming, and with the progress of flowering, the values decreased. However, statistical differences were found for O. flaemingina, O. paradoxa, and O. rubricaulis. The mass of pollen produced per unit area was also a species-specific characteristic and was related to the abundance of flowering. The greatest amount of pollen was produced by O. flaemingina (30.6 g m-2), which was almost three times more than that produced by O. rubricaulis (10.9 g m-2). The protein content of pollen grains was relatively low and on average amounted to 15.4%. The Oenothera species examined in this work may be considered valuable pollen yielding plants. Nevertheless, given the invasive potential of species from subsect. Oenothera, precautions are suggested during cultivation and/or planting these taxa in bee pastures, in order to prevent uncontrolled spread into new areas. [ABSTRACT FROM AUTHOR]

Nectar secretion was noted both in the male and female floral phases of the protandrous flowers of Campanula patula (Campanulaceae). Female-biased sugar accumulation was evidenced and plasticity in the duration of sexual phases observed. Flowers in the male phase produced twofold less nectar with lower sugar concentrations compared to female-phase flowers. The sugar mass content averaged 0.6 mg ±0.45 SD per flower in the male phase and 1.4 ±0.5 SD per flower in the female phase. The pollen mass averaged 0.16 mg ±0.10 SD per flower. An understanding of the evolution of functional relationships between floral sexes requires consideration of the compensation of the reproductive costs, including the plastic response to interdependent factors, i.e., photosynthesis and growth, the effect of pollinators, pollen robbers, and external environmental forces. [ABSTRACT FROM AUTHOR]

In this study, we evaluated if railway embankments and road verges create refuge habitats for bee flora across agricultural landscape. The survey was conducted in 2009-2012, in the Lublin Province, SE Poland. Data on the bee forage flora were obtained while making floristic charts along 60 transect plots × 300 m, with a total length of 18 000 m, for each type of linear structure. Forage bee flora was compared with respect to species richness, diversity, and evenness indices. The canonical correspondence analysis (CCA) was used to characterize relationship between species composition and environmental variables. The bee forage species richness and abundance were significantly greater on railway embankments than on road verges. The composition of species varied considerably; the number of bee forage species common to both habitats was only approximately 38% in entire data set. Most good-value bee forage species were recorded along the embankments of railways with an intermediate traffic volume. Bee forage species diversity benefits from the location of habitat elements (forests or meadows), primarily if the distance is <50 m. The lack of dense patches of valuable bee forage species in the road verges was related to the high density of non-nectariferous graminoids. Our results demonstrate how the value of man-made areas in an agricultural ecosystem can vary with respect to floral resources across the landscape, suggesting that it is inappropriate to generalize about agricultural systems as a whole without first addressing differences among habitats. [ABSTRACT FROM AUTHOR]

Railway areas are considered as large greenspaces and are recognized important in improving the biodiversity and dynamic of urban flora. In this study, we examined the flora composition and diversity along intra-city railway lines in Lublin, SE Poland and Lviv, W Ukraine. The flora has been analyzed in terms of species composition (multivariate ordination techniques), life span, life form, type of pollination mode, seed dispersal, life strategy sensu Grime, hemerophoby, urbanity degree, and in terms of habitat preferences using ecological indicator values. The multivariate analysis (CCA) clearly revealed that abiotic factors (topographical), weather elements (annual precipitation and air temperature), and soil attributes (moisture, trophy, pH, salinity) differed between two cities and impacted on the differences in railway flora composition. Plants growing on the intra-urban railway areas are mainly hemicryptophytes/perennials, C, CR, CRS-strategists, insect-, self-, or wind-pollinated, reproducing by seeds and mainly dispersed by wind. Intra-urban railway areas are predominated by native species, however the participation of invasive alien species is higher than their proportion in domestic floras. The share of invasive species is greater in railway areas of Lviv, ca. 12% (45 species) compared to 8% in Lublin (36 species). Spontaneous flora in intra-urban railway areas represent distinct adaptations to unique urban-industrial ecosystems with different degree of anthropogenic disturbance. [ABSTRACT FROM AUTHOR]

In Poland, like in other parts of Central Europe, dry grasslands significantly contribute to the biodiversity of both fauna and flora. Anthropogenic pressure impair many species of xerothermic habitats, and several populations face an increased risk of extinction. The goal of the study was to define factors that may affect the size of wild populations of Anemone sylvestris L., a protected species in Poland, with both a short- and long-term perspective, and to examine the influence of vegetation changes on the density, the abundance of flowering and male function (pollen production, pollen viability), as well as seed set. In situ observations were performed in 2005-2006 and 2011-2012 in three populations located on the Lublin Upland, SE Poland. The reduction in population density and A. sylvestris blooming was exacerbated by the expansion of the shrubs, but not by Brachypodium pinnatum. Male characteristics of A. sylvestris, i.e. pollen amount per multi-staminate flowers or pollen viability appeared to decrease under pressure of shrub competition. Populations with limitation of male function had impaired degree of seed set. Various consequences for the functioning of populations within a metapopulation system can be expected due to substantial qualitative and quantitative disorders in pollen traits. It is crucial that successful recovery programs for A. sylvestris primary should aim to conserve and manage the habitat. [ABSTRACT FROM AUTHOR]

Knowledge of the lowering phase and plant pollination ecology is very important for understanding the life history of long-lived perennials. In the case of rare species, the information may have implications for conservation practices. Our studies on lower morphology and blooming biology of the vulnerable plant Senecio macrophyllus M. BIEB. were conducted in situ (lowering, activity of insect visitors) in the largest population in SE Poland and in laboratory (light and scanning electron microscopy). The disc florets open diurnally with most intensive anthesis in the early afternoon and attract insect visitors with nectar and pollen. In highly protandrous disc florets, pollen viability decreases in time, whereas stigma receptivity increases. The upper part of the pistil forms a brush-like pollen presenter, covered with unicellular trichomes with chromoplasts. Pollen presentation lasts 4-11 hours per floret, and 8 days in a single head, the main function of which is to extend the availability of male gamets for reproduction. The number of florets per head, the head size, and the number of pollen grains produced per anther, and the pollen grain viability differed significantly between microsites. The finding indicates that, apart from the biotic factors, abiotic conditions may considerably influence generative reproduction of the species. In the study area, the principal visitors of S. macrophyllus lowers were Hymenoptera, with predominance of Apis mellifera (53.4% of visits). The remarkable share of butterflies (13.9%) recognized as the long-distance moving insects may improve the genetic variability of individuals within a fragmented population. A more detailed study is necessary to explain the role of insect visitors in effective pollination and in gene transfer between patches. The assessment of optimal conditions for the generative reproduction is fundamental for the in situ conservation of this rare species. [ABSTRACT FROM AUTHOR]

Although the knowledge of pollination systems of rare and threatened species is one of the principles for development of optimal conservation and management strategies, the data about their pollination requirements are scarce or incomplete. Different problems are listed (xerothermic habitat disappearance, overgrowing of patches, plant biology i.e., slow plant growth, problems with seed germination) among the possible causes of Adonis vernalis being threatened, but until now no consideration was given to the lowering biology and pollination. he observations of lowering biology of A. vernalis (Ranunculaceae), a clonal species, were conducted in an out-of- compact-range population, in the Lublin Upland, Poland (51°18 '55" N, 22°38'21" E), in 2011-2013. The reproductive potential of A. vernalis is related to the population age structure, pollination syndrome, and breeding system. The lowers exhibit incomplete protogyny. The dichogamy function is supported by different (biological, morphological) mechanisms. Stigma receptivity occurred about one day before anthers started shedding self-pollen, and pollen viability was increasing gradually during the lower life-span (66.3% in distal anthers vs. 77.3% in proximal). The decrease in pollen production and in pollen viability coincided with the lowest degree of seed set, irrespective of the pollination treatment. Pollen vectors are necessary for efficient pollination, as the proportion of pistils setting fruits after open pollination (41-82.1%) was significantly higher compared to spontaneous self-pollination (only 5.5-12.3%). The pollination requirements together with pollen/ovule ratio (P/O = 501) indicate a facultative xenogamous breeding system in A. vernalis. Therefore, in the conditions of the global lack of pollinators, improper pollination may weaken the population by leading to a decrease in the proportion of recombinants, and in addition to other factors, may accelerate extinction of small A. vernalis populations. [ABSTRACT FROM AUTHOR]

This study investigated the floral biology and pollen quantity and quality of Campanula bononiensis L. (Campanulaceae), a protected species in Poland. Observations and measurements were made during the years 2007-2009 in natural phytocoenoses from the Festuco-Brometea class situated within the Lublin area, SE Poland. A considerable decrease (approx. 87%) in population density was observed. Significant variations both in the amount of pollen (18.5%-34.8 % of pollen in the total anther dry weight, i.e. 0.5-1.5 mg per 10 anthers) and in pollen viability (38.8-97.0%) were noted. Both a low amount of pollen and low pollen viability may reduce the reproductive success of individuals. The most frequent visiting insects were bees (Apoidea), including solitary bees 45.7%, honeybees 20.4%, and bumblebees 11.4%. Dipterans, coleopterans (weevils), lepidopterans and ants were also recorded, implying a strong impact of C. bononiensis on insect biodiversity within grasslands. [ABSTRACT FROM AUTHOR]

Flowering phenology, diurnal dynamics of blooming, insect visitation and pollen production in Aconitum lycoctonum L. and Aconitum carmichaelii Debeaux were investigated in 2012-2013 in the Lublin area, SE Poland. Flowering of A. lycoctonum occurred in June/July, whereas A. carmichaelii bloomed in September/October. Both Aconitum species differed in terms of the diurnal pattern of flowering. The flowers of A. lycoctonum started opening at 5.00, whereas those of A. carmichaelii started blooming at 8.00 (GMT+2h). The species differed in the number of anthers per flower, the size of anthers, and the mass of pollen produced in anthers. As a result, the flowers of A. lycoctonum produced less pollen (mean = 1.0 mg per 10 flowers) than the flowers of A. carmichaelii (mean = 8.2 mg per 10 flowers). The estimated pollen yield was 0.2 g per m² for A. lycoctonum and 1.6 g per m² for A. carmichaelii. The flowers of both Aconitum species were foraged exclusively by bumblebees with the predominance of the long-tongued Bombus hortorum. Nectar was a more attractive floral reward than pollen. The propagation of Aconitum lycoctonum and A. carmichaelii in ornamental gardens may support the conservation of bumblebees whose populations are steadily declining. [ABSTRACT FROM AUTHOR]

The observations were conducted in long-term sequence studies in the years 2006, 2009, 2013, in the Lublin area, Poland (51° 16' N, 22° 30' E). The flowering phenology, diurnal pattern of blooming, pollen production and insect visitation to the shrubs of Syringa oblata Lindl. var. dilatata (Nakai) Rehd. and S. meyeri 'Palibin' Schn. were examined. Syringa oblata var. dilatata and S. meyeri 'Palibin' bloomed from the mid May till mid June. The species are characteristic of early morning diurnal pattern of blooming, with approx. of 60% of daily instalment of flowers opened before 9.00 (GMT + 2h). Both species studied had the corolla tube 2-fold deeper during the pollen shedding phase compared to bud stage (mean = 14.9 mm ± 3.2 SD vs. 7.8 mm ± 2.8). No species effect was found for the size of anthers, for the mass of pollen produced in anthers and for the pollen viability. A constant number of 2 stamens in the flowers of Syringa species entailed the pollen yield was derivative mainly to the number of developed flowers. Therefore significant differences were noted for the pollen yield between individual shrubs (mean 0.9 kg for S. meyeri 'Palibin', and 8.1 kg/ha for S. oblata var. dilatata ). The Syringa oblata var. dilatata and S. meyeri 'Palibin' due to their attractive flowering period, and the abundance of blooming are suitable for different ornamental designs in urban areas. Unfortunately, despite the entomophilous flower traits, the insect visitors appeared sporadically. [ABSTRACT FROM AUTHOR]