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1

Causes of variation in generative reproduction of Polygonatum odoratum (Miller) Druce in N-Poland populations

100%
Kosinski I.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 3
Seed production, seedling establishment and survival into the generative phase are important stages in the life cycles of clonal species. The aim of this study was to assess the variation of generative reproduction and factors affecting its size in the natural populations of Polygonatum odoratum. It was hypothesized that: (a) seed output in a population is strongly affected by biotic and abiotic environmental factors, and weakly related to population abundance, (b) seeds’ ability to germinate and seedlings’ survival depend on the seed size. The field studies were conducted in five populations of Polygonatum odoratum in 2000–2011. Sex allocation in flowers was estimated as the number of hermaphrodite flowers on shoots and ovules in ovaries. Generative shoots, flowers and fruits on them were recorded in each population. The type and size of damage to plants by large herbivores and insects were recorded. The three sowing experiments were conducted in order to estimate seedling performance and survival. The populations differed significantly in the fraction of hermaphrodite flowers and ovule number. The number of generative shoots and flowers on them as well as the seed output significantly differentiated the populations and patches. In the first year of study, the mean seed output ranged from 0.3 to 123.7 m⁻², and it markedly decreased in two populations, where there was no seed at last years of study. Generative shoots were often grazed by roe-deer, leaves were eaten by Phymatocera aterrima and flowers were infested by Contarinia polygonati larvae. Seedling emergence was significantly correlated with the mean seed mass. Seven-year-old individuals were able to reach generative phase. In conclusions, the results suggest that the generative shoots provide a long-term inflow of seeds to the population. Under experimental conditions, substantial survival enabled the plants to potentially reach generative maturity. In studied populations, the most important reason for dynamic of seed output was animal pressure (in order – grazing, flower infestation and defoliation). The effect of these biotic factors was visible in a short period – in the current year. In contrast, the impact of abiotic factors (e.g. lighting), was appeared in a longer period.
2
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The life-history traits and seedling recruitment of Dianthus superbus L. in different stages of meadow overgrowing

100%
Kostrakiewicz-Gieralt K.
Acta Agrobotanica
|
2014
|
tom 67
|
nr 2
A study of the life-history traits and seedling recruitment in small and isolated populations of a rare clonal species, Dianthus superbus L., was carried out in the years 2011–2012 in Kraków-Kostrze (Southern Poland). Observations were conducted in unmanaged Molinietum caeruleae meadows situated along the successional gradient. The patch representing the initial stage of succession (P1) was dominated by small species creating delicate erect or procumbent stems, the patch representing the temporary stage of succession (P2) was prevailed by large-tussock grasses and tall-growing macroforbs, while the patch representing the terminal stage of succession (P3) was partly overgrown by bushes and trees. The number of generative shoots, flowers, fruits and seeds of Dianthus superbus L. diminished gradually from P3 via P2 to P1. The increase in abundance of generative shoots and flower number in the vicinity of tall plants contributes to increased visibility of inflorescences and may enhance the chances for nocturnal pollinator visits. A significant production of fruits and seeds in competitive neighborhood may augment the chances for successful dispersal and colonization of new, perhaps more favorable habitats. The recruitment of seedlings occurred only in artificially created gaps in plant canopy and litter. The appearance of seedlings and their survivorship were better in P1 than in P2 and P3. Such a phenomenon might be due to the locally rising water level and the diminishing amount of light reaching to the soil area along the successional gradient. Concluding, it should be asserted that a low production of generative shoots, flowers, fruits and seeds by the population of Dianthus superbus L. established in the patch dominated by small meadow species is compensated by the highest seedling recruitment and their survival. On the other hand, a substantial production of generative structures is not sufficient to ensure the persistence of populations in meadows in advanced stages of secondary succession.
3

Flower development of greenhouse chrysanthemum

100%
Kuklina E. A.
Acta Biologica Cracoviensia. Series Botanica
|
2003
|
tom 45
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nr 1
A comparative morphogenetic study of reproductive organs of chrysanthemums is conducted using morphological analysis. Morphological changes during the development of a generative shoot and organogenesis from first through ninth phases were described. The flat apex becomes spherical in form. An inflorescence apical meristem initiates involucral bract. An initiation of floret primordia is followed an acropetal sequence. Floral meristem produces corolla, then 5 staminata primordia and two-lobed pistillata primordia. The ray floret and the disc floret both form 5-lobed corolla, but 2 lobes of the corolla of the ray floret stop their growth. Staminata primordia of the ray floret produce sterile staminodia or do not continue their development. At phase IX during flowering, 4 stages are identified. A dehiscence of introrse anthers and anthesis occur in a closed disc floret. There are protoandria and different arrangements of mature anthers and mature stigmata in disc florets .
4

The content of flavonoids and polyphenolic acids in inflorescences of sandy everlasting [Helichrysum arenarium [L.] Moench] from natural stands and plantations

80%
Sawilska A. K., Mielcarek S.
Herba Polonica
|
2009
|
tom 55
|
nr 3
118-126
During the years 2007–2008 the content of flavonoids and polyphenolic acids in inflorescences of Helichrysum arenarium (L.) Moench was analyzed in specimens from natural stands and plantations. Plants cultivated in experimental plots originated from in vitro plantlets. The amount of flavonoids in inflorescences from experimental plots was higher and attained its maximum at 1.19% compared with 0.84% observed for plants from natural stands. In herbal material collected in 2008 the content of flavonoids was lower. The tendency was not observed for polyphenolic acids. Within the study period their amount ranged over the interval 0.74–2.82%. It was also found that dry mass of inflorescences from natural stands was higher than that for cultivated plants by 30.9%. In contrast, the density of generative shoots was 5.2-fold higher in natural stands. It was shown that Sandy Everlasting plantations could yield up to 3.4-fold more herbal material which is of a better quality (contains more biologically active compounds) than that from natural stands.
5

The influence of shadow created by adjacent plants on phenotypic plasticity of endangered species Trollius europaeus L. Ranunculacea]

80%
Kostrakiewicz K.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 4
625-634
The assessment of phenotypic plasticity expressed as the response to abiotic and biotic site factors is important for successful conservation of endangered and threathened species. In Poland one of the strictly protected plant requiring an active conservation is globeflower Trollius europaeus L. It is the perennial forb, consisted of numerous dark green, deeply cut basal leaves and generative shoots with flowers composed of several multi-ovulate carpels. The investigations of morphological traits of Trollius europaeus i.e. number and height of generative shoots and basal leaves as well as the production of flowers, multi-follicles and follicles at stem- and cluster levels, were carried out between 2005 and 2008 on two patches of Molinietum caeruleae localized in Kraków vicinity (Southern Poland) and having different height of litter and herb layer. The study plot labelled NS- “not shaded” (2 000 m²) was prevailed by perennials with delicate procumbent or erect stems, small-tussock grass or short rosetteforb species. The height of the tallest plant has not exceeded 98 cm, while the litter layer measured from 10 cm to 28 cm. The study plot named SH- “shaded” (6 000 m²) was characterised by presence of tall perennials as well as grass and sedges forming large compact tussocks. The tallest plants attained 186 cm, whereas the layer of litter reached from 18 cm to 42 cm. In NS plot -32 clusters were observed, whereas in SH plot 39 clusters occurred. In both populations, clusters were situated in close vicinity, forming large aggregations. The number of aboveground units per cluster in both populations were similar. The longer petioles (higher petiole average length), caused by maximization of light capture were noted in SH, than in NS plot. In SH plot higher sexual shoots were also noted as well as greater number of flowers per shoot. Such phenomenon presumably makes the plant more attractive for pollinators and thus pollen receipt and donation. The similar number of flowers and multi-follicles per cluster were observed in both populations, while the greater number of follicles was observed in NS, than in SH plot. Due to morphological plasticity established clusters of T. europaeus might presumably endure among the vegetation cover or adapt to new environmental conditions. It might be considered that making the gaps in vegetation cover and litter can be an effective way for active protection of Trollius europaeus populations.
6
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Variability of leaf morphology from generative and vegetative shoots of Rubus capitulatus and R. kuleszae (Corylifolii section, Rosaceae)

80%
Kluza-Wieloch M., Maciejewska-Rutkowska I., Gawron-Gzella A., Dudek-Makuch M., Drapikowska M.
Roczniki Akademii Rolniczej w Poznaniu. Botanika-Steciana
|
2013
|
tom 17
Leaves from generative and vegetative shoots of Rubus capitulatus and R. kuleszae of Corylifolii section were investigated. The study was to demonstrate the variability of leaves of both types of shoots, and at the same time an examination on the contents of polyphenols and phenolic acids in their blades carried out. Selected blade traits, such as was: length, width, elongation, perimeter, dissection index, area, rectangularity and circularity were measured using computer program and statistically analysed. Additionally, fresh and dry leaves were weighed and the percentage of preserved mass of particular samples was calculated. A statistical analysis revealed the area to be the most variable feature in both species and both types of shoots. Leaves from vegetative shoots were the most similar to each other and the length, width, perimeter and area were the most strongly correlated traits to each other. The leaves of generative shoots of both species contained less water than the leaves of vegetative ones.
7

Wyksztalcanie pedow generatywnych a plonowanie plantacji nasiennych traw

61%
Falkowski M., Kukulka I., Kozlowski S.
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin
|
1996
|
tom 199
99-107
8

Wartość pokarmowa mieszanek traw w użytkowaniu kośnym - pierwszy pokos i pastwiskowym - drugi pokos

61%
Borawska-Jarmulowicz B.
Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin
|
2003
|
tom 225
183-191
Celem badań była ocena wartości pokarmowej mieszanek późnych odmian gatunków traw użytkowanych kośnie i pastwiskowo na podstawie ich składu chemicznego oraz udziału w plonie poszczególnych komponentów z uwzględnieniem pędów generatywnych i wegetatywnych (struktura). Badania prowadzono w latach 1990–1992 w centralnej Polsce na dwóch doświadczeniach w naturalnych siedliskach łąkowych; w umiarkowanie wilgotnym — doświadczenie w użytkowaniu kośnym, a w umiarkowanie suchym — w użytkowaniu pastwiskowym. W badaniach uwzględniono dwie późne mieszanki (łąkową i pastwiskową), których wartość paszową oceniano w pierwszym pokosie i drugim symulowanym wypasie (“wypas”) ze względu na zbliżony termin sprzętu w obu sposobach użytkowania. Nawożenie (kg×ha-1): N — 60 pod każdy pokos i N — 50 pod każdy “wypas”, P — 80 jednorazowo wiosną, K — 120 w dwóch równych częściach. Określano udział w plonie komponentów mieszanek (analiza botaniczno-wagowa), udział pędów generatywnych i wegetatywnych w odmianach traw oraz wartość pokarmową mieszanek: białko ogółem, włókno surowe, strawną suchą masę i makroelementy — P, K, Mg, Ca, Na. W użytkowaniu kośnym stwierdzono najwyższą wartość pokarmową mieszanki w pierwszym roku użytkowania (1990 rok), o czym mogła decydować Lolium perenne odm. Arka dominująca w runi (ok. 44%). W kolejnych latach wartość paszy obniżała się w wyniku znacznie zmniejszającego się udziału tego komponentu i wzrastającego udziału Dactylis glomerata odm. Baza (dominowała w trzecim roku), a także Bromus inermis odm. Brudzyńska. W użytkowaniu pastwiskowym wartość paszy w okresie badań była dobra i zależała przede wszystkim od Lolium perenne odm. Arka (ok. 70%) oraz w mniejszym stopniu od Dactylis glomerata odm. Baza. Wartość pokarmowa mieszanek zależała również od udziału pędów generatywnych i wegetatywnych w dominujących odmianach traw; wyraźnie — w użytkowaniu pastwiskowym, w mniejszym stopniu — w użytkowaniu kośnym.
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