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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Selected aspects of tiny vetch [Vicia hirsuta (L.) Gray S.F.] seed ecology: generative reproduction and effects of seed maturity and seed storage on seed germination

100%
Kucewicz M., Mackiewicz K., Zrobek-Sokolnik A.
Acta Agrobotanica
|
2010
|
tom 63
|
nr 1
Vicia hirsuta (L.) Gray S.F. (tiny vetch) is a common and persistent segetal weed. Tiny vetch seeds and pods reach different stages of maturity during the crop harvest season. Some seeds that mature before cereal harvest are shed in the field and deposited in the soil seed bank, while others become incorporated into seed material. The objective of this study was to describe selected aspects of tiny vetch seed ecology: to determine the rate of individual reproduction of vetch plants growing in winter and spring grain crops and to evaluate the germination of seeds at different stages of maturity, subject to storage conditions. The seeds and pods of V. hirsuta were sorted according to their development stages at harvest and divided into two groups. The first group was stored under laboratory conditions for two months. In the autumn of the same year, the seeds were subjected to germination tests. The remaining seeds were stored in a storeroom, and were planted in soil in the spring. The germination rate was evaluated after 8 months of storage. Potential productivity (developed pods and flowers, fruit buds) was higher in plants fruiting in winter wheat than in spring barley. Vetch plants produced around 17-26% more pods (including cracked, mature, greenish-brown and green pods) and around 25% less buds in winter wheat than in spring barley. Immature seeds were characterized by the highest germination capacity. Following storage under laboratory conditions and stratification in soil, mature seeds germinated at a rate of several percent. After storage in a storeroom, seeds at all three development stages broke dormancy at a rate of 72- 75%. The high germination power of tiny vetch seeds stored in a storeroom indicates that this plant can be classified as an obligatory speirochoric weed species.
2
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The effect of achene heteromorphism on progeny traits in the shaggy soldier [Galinsoga ciliata (Rafin) S. F. Blake]

100%
Kucewicz M., Gojlo E., Kowalska A.
Acta Agrobotanica
|
2010
|
tom 63
|
nr 2
The shaggy soldier [Galinsoga ciliata (Rafin) S. F. Blake], family Asteraceae] is an invasive species that poses a growing threat to crop production. This annual plant produces heteromorphic achenes in a capitulum type inflorescence. The objective of this study was to compare selected morphological and phenological parameters and the success of generative reproduction in plants developed from peripheral and central achenes of the capitulum. The somatic variability of G. ciliata diaspores contributed to differences in the growth rates, development and fertility of the resulting populations. The progeny of central diaspores developed at a slower rate than the individuals derived from peripheral achenes, but at the end of their life cycle, the offspring of dimorphic achenes formed homogenous groups as regards height values. On average, the initial phenophases of G. ciliata plants derived from central achenes began one day later, and they entered the flowering stage eight days later than the individuals developed from peripheral seeds. At the initial growth stage (experimental day 65 to 83), the progeny of central achenes produced fewer capitula. On day 133, the individual fertility of the plants derived from central diaspores was 10% higher on average in comparison with the offspring of peripheral achenes.
3
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Generative reproduction and external conformation of Echinochloa crus-galli [L.] P. Beauv. plants under various density conditions

100%
Kucewicz M., Holdynski C.
Journal of Plant Protection Research
|
2003
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tom 43
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nr 1
4
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Regeneration of Nardus stricta subalpine grasslands in the Giant Mountains [Krkonose]

100%
Hejcman M., Nezerkova P., Pavlu V., Gaisler J., Lokvenc T., Pavlu L.
Acta Societatis Botanicorum Poloniae
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2005
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tom 74
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nr 3
The origin of Nardus stricta dominated subalpine grassland (Nardo-Caricion rigidae alliance) is a frequently discussed topic in the Giant Mountains (Karkonosze in the Czech Republic). Many researchers considered them, as secondary stands arisen after Pinus mugo removal and by consequent oligotrophization of original plant communities, caused by long-term rough grazing and hay making activities without manuring. On the contrary, they are recognized as natural due to inability of generative reproduction of N. stricta and the very slow vegetative spread there. The aim of this study was to find proofs for generative reproduction of mat grass in subalpine conditions of the Giant Mountains. We identified a Pinus mugo nursery with arable land abandoned in 1956 and compared its vegetation with that of the surrounding area. Dense and homogenous sward dominated by N. stricta developed during the succession on the old arable land for 48 years, and it is an indisputable proof of generative reproduction of N. stricta there. Synthesizing historical facts on human activities in the past and the results of our contemporary vegetation analysis, we conclude that the Nardo-Caricion rigidae grassland was capable to spread relatively quickly, when agricultural activities above the upper timber line were introduced.
5

Reproduction of Primula veris L. plants in populations from natural localities

100%
Morozowska M.
Herba Polonica
|
2004
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tom 50
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nr 3-4
The reproduction ability of Primula veris L. plants was described on the basis of six-year observa­tions on permanent plots in populations from natural localities. Cowslip individuals in different life stages were mapped according to topographical distribution. The vegetative multiplication symptoms of the plants were also recorded. The mean survival rate of seedlings to the juvenile sta­ge was similar in both populations, amounting to about 16.5%. The highest survival rate was found for juveniles (44.3-57.6%) and immature (31.4-48.6%) individuals, while the lowest number of indi­viduals turned from the virginile into the generative stage (2.2-5.7%). The efficiency of the gene­rative reproduction measured by the ratio of the number of generatively recruited flowering plants to the observed number of seedlings was 0.22-0.42%, depending on the population.
6

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

84%
Kosinski I.
Polish Journal of Ecology
|
2013
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tom 61
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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.
7

Flowering and generative reproduction in isolated populations of endangered species Carlina onopordifolia Besser [Asteraceae] in Poland

84%
Denisiuk Z., Chmura D., Adamski P.
Polish Journal of Ecology
|
2009
|
tom 57
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nr 1
89-97
Carlina onopordifolia is longlived monocarpic perennial plant, which reproduces only generatively, however, it flowers and fruits only once in lifespan (10–20 yrs) and after seeds development it dies. Due to this type of reproduction the abundance of population depends on amount of produced seeds, moreover the plant flowers more abundantly every 2–3 years. The plant is highly specialized in respect to habitat and micro-climate conditions. It grows on calcareous and sun-heated slopes, where xerothermic grasslands grow with contribution of species typical for steppe vegetation. In Poland it is a very rare species known only from seven isolated natural stands in south and east part of the country. Differences and year-to-year fluctuations in the frequency and the abundance of generative and vegetative specimens in natural stands were studied in 2006 and 2007 years. The regional differences in leaf rosette size and size of inflorescences were examined. The abundance of population in all stands increased from ca. 13600 plants in 2006 to ca. 31950 in 2007. The G test revealed significant decrease in frequency of flowering plants vs. barren plants between the years in four of all seven stands. The significant differences in mean diameter of leaf rosettes (45; 49; 52 cm) and mean diameter of anthodium of generative specimens (7.17; 7.74; 8.27 cm) were observed in three the most geographically distinct and the most abundant populations. The mean values of leave rosette (44.20; 49.31 cm) and sizes of anthodiums (6.05; 7.61 cm) also changed significantly between the years 2006 and 2007, respectively for all data. It can be concluded that in all stands of the thistle in Poland the synchronization of blooming phase takes place. The observations implicate conclusions important for practice of monitoring which must be conducted at least for two vegetative seasons covering the whole phenology of the species in order to prevent the artifacts.
8

Demographic versus genetic [RAPD] variation between and within two populations of the clonal plant Paris quadrifolia L. [Liliaceae]

84%
Kosinski I., Stefanowicz-Hajduk J., Ochocka R.
Polish Journal of Ecology
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2009
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tom 57
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nr 2
303-311
The two populations of Paris quadrifolia L. were studied in isolated habitats in a currently fragmented landscape. Both populations were located in deciduous forests, the first (A) – on fresh mineral and acidic soil, and the second (B) – on wet organogenic, less acidic and more fertile soil. We hypothesized that genetic variation should be higher within population of more fecund plants, and that genetic distance between the two populations that occupy different isolated habitats in a fragmented landscape should be high. Demographic characteristics of populations were studied in the 2000–2005 period. In patches of both populations, 22 permanent plots measuring 1m² each were designated. For molecular testing 41 samples from both populations were selected. The share of generative shoots was higher in the population A than population B (0.35 and 0.20, respectively). However, the fecundity of ramets expressed as the number of seeds in the ripe fruit was lower in A than in the B population (15 versus 21 seeds). The germination ability was significantly higher for the seeds from A than from the B population (79% versus 44%). The survival of the juveniles was high in both populations (54 and 76%). The Random Amplified Polymorphic DNA (RAPD) analysis with the application of five primers permitted identifying 91 loci. The estimation of genetic diversity was based on polymorphic loci, the share of which was average 44%. Nei’s gene diversity (h) was higher in the A than B population (0.28 versus 0.22). The genetic diversity between the populations was not large (GST = 0.14). Clonal diversity was very high, G/N ratio = 1, and cluster analysis showed intermingling between samples from both the populations. There were quite a small genetic distance (D = 0.10), and a rather high level of gene flow (Nm = 1.51) between the populations from currently isolated habitats. The obtained results indicate that the genetic diversity was lower within population of more fecund plants from more productive habitat.
9

Cvihtihnnja jj plodonoshennja vidihv Corylus L. v Ukrajinih

84%
Kosenko I.
Arboretum Bolestraszyce
|
2002
|
nr 09
79-86
10

The ecological importance of seed dimorphism in corn spurry (Spergula arvensis L.). I. The effects of day length on seed germinability

84%
Kucewicz M., Gojlo E.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 4
Spergula arvensis L. (corn spurry) is a heteromorphic species of the Caryophyllaceae family, that produces two types of seeds with a smooth (non papillate, NP) or papillate (P) coat. The plant flowers and produces fruit between May and September, a period marked by a gradual decrease in day length. The objective of this study was to determine the effects of day length on the germinability of heteromorphic seeds. In addition, we examined the frequencies of non papillate and papillate seeds in four populations. Germination tests were performed on seeds harvested from plants grown in a greenhouse under conditions simulating long days (17 hour photoperiod) and short days (12 hour photoperiod). Heteromorphic seeds incubated in water at various temperatures (10–30°C) over a period of 4 weeks remained dormant. Corn spurry seeds had different responses to the addition of nitrate after four weeks of pre-treatment. Both seed morphs kept at a temperature of 10–20°C did not germinate or their germination rates did not exceed 6%. Seeds incubated at 25°C and 30°C broke dormancy. NP seeds from plants growing under long- and short-day photoperiods were characterized by higher germinability than P seeds at both temperatures. The above-mentioned results indicate that variations in light exposure during plant growth and development do not contribute to somatic heteromorphism of S. arvensis seeds. Day length has no significant effect on the germination of heteromorphic seeds. The populations were heteromorphic with respect to plants having papillate seeds and plants having non papillate seeds. The majority of individuals were monomorphic and produced capsules containing only one type of seed. Heteromorphic individuals produced capsules containing: a) NP seeds, and b) P seeds, and c) mixed seeds. The analyzed populations were characterized by a predominance of P seeds in the overall seed pool.
11

Generative reproduction in Rumex confertus Willd. populations

84%
Stosik T.
Electronic Journal of Polish Agricultural Universities. Series Biology
|
2007
|
tom 10
|
nr 4
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Do small-scale gaps in calcareous grassland swards facilitate seedling establishment?

84%
Baba W., Kompala-Baba A.
Acta Societatis Botanicorum Poloniae
|
2005
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tom 74
|
nr 2
In this study we analyzed gaps originated in different seasons of the year vs. places of close vegetation in calcareous grasslands in terms of their suitability for seedling germination and establishment. Gaps, irrespective of the time of their origin, significantly promoted seedling emergence as compared with close swards. However, the season of gap creation influenced the rate of seedling germination/emergence. Seedlings occurred more frequently in autumn and spring gaps than in the summer ones. The highest mean number of seedlings and of their species were noted in autumn openings. However, the subsequent survival of seedlings in autumn gaps was low. On the contrary, in spring gaps juveniles occurred with the significantly highest mean number, frequency and species richness. The above results pointed to the positive, although very limited role of artificially created gaps as places favouring seedlings establishment.
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Generative reproduction efficiency and the population age structure of Rumex confertus Willd.

84%
Stosik T.
Acta Agrobotanica
|
2006
|
tom 59
|
nr 2
Rumex confertus is one of the alien species vigorously entering native meadow as well as ruderal communities in major river valleys. In about a hundred years the species invaded almost the whole territory of Poland. Many reports stating that Russian Dock may reach high coverage in various phytocoenoses contradict those of its low generative reproduction efficiency. In communities where it most frequently occurs, germination is hindered by the lack of empty spaces. In such conditions the population size remains stable due to vegetative reproduction. Only hay-growing meadows seem to promote the influx of new genets into population, which is likely associated with vegetation cover removal and periodic reduction of competition from other species.
14

Effectiveness of the generative reproduction of Vaccinium myrtillus and Vaccinium vitis-idaea in the environment under strong antropopressure

84%
Zaufal T.
Acta Biologica Silesiana
|
2002
|
tom 36
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Influence of environmental factors on reproduction of polar vascular plants

67%
Kellmann-Sopyla W., Pastorczyk M., Gielwanowska I.
Papers on Global Change
|
2011
|
nr 18
In the last few decades, changes of reproductive pattern of polar vascular plants have been observed, for the benefit of generative propagation. The reasons for this phenomenon are attributed to intensively following climate change, whose effects may be various. Warming causes the production of the greater number of generative structures, with higher quality. Our macroscopic observations conducted on specimens of polar vascular plants, cultivated in University of Warmia and Mazury greenhouse, indicate that the effect of temperature increase on flower development and seed formation is inconsistent. On the other hand enhanced levels of UV-B radiation can negatively affect seedlings. The complexity of the climate change causes tremendous difficulties in defining a clear and unquestioned way of modifications during the reproductive phase of the described plants.
16

What do we know about calreticulin and its role during key events in sexual reproduction of flowering plants?

67%
Lenartowska M.
Acta Biologica Cracoviensia. Series Botanica. Supplement
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2014
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tom 56
|
nr 1
17

Somatic embryogenesis in Gentiana pneumonanthe L.

67%
Bach A., Pawlowska B.
Acta Biologica Cracoviensia. Series Botanica
|
2003
|
tom 45
|
nr 2
A method for micropropagation of the protected species Gentiana pneumonanthe L. by somatic embryogenesis (SE) was elaborated. For SE induction, secondary explants of leaves and apical meristems from in vitro cultures were successfully used. Tests of callus induction were carried out on ten media containing BA (0.04-8.0 µM) and Picloram or 2,4-D (4.0-8.0 µM). The greatest amounts of embryogenic callus developed on media containing 2,4-D and also when the incubation period in darkness was prolonged. Embryos matured on media with reduced content of auxins [Picloram or 2,4-D (0.8 µM or 0.08 µM) and BA (0.8 µM)] and germinated on hormone-free media. Cytometric analysis of the callus and plants obtained from somatic embryos showed that DNA content differed from that of the mother plants, but acclimatized marsh gentians contained the same amount of DNA as donor plants.
18

Structure, dynamics and population biology of Dentaria glandulosa [Cruciferae]. III. Effectiveness of generative and vegetative reproduction

67%
Tumidajowicz D.
Polish Botanical Studies
|
1995
|
tom 10
19
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The effect of dominant species on numbers and age structure of Iris sibirica L. population on blue moor-grass meadow in Southern Poland

67%
Kostrakiewicz K.
Acta Societatis Botanicorum Poloniae
|
2007
|
tom 76
|
nr 2
Two populations of Iris sibirica, a clonal species protected by law in Poland, occurring in patches of Molinietum caeruleae, of similar floristic composition although with different dominant species, were studied. In the Stanisławice locality, species with a high competitive potential prevailed, contrary to the Opatkowice locality, where the species of low competitive potential dominated. It was established that vegetative propagation ensures the continued presence of populations in both localities, although the proximity of plants with high competitive potential limits the vegetative propagation of ramet clusters of Iris sibirica. Despite the high level of seed production, the recruitment of seedlings in both patches is possible only in artificially created gaps. The field observations support the conclusion that creating gaps allowing for germination of seeds and development of seedlings, as well as eliminating expansive neighbours allowing proliferation of ramet clusters of Iris sibirica, is an affective way of protecting populations of this species.
20

Biology of generative reproduction of Colobanthus quitensis (Kunth) Bartl. from King George Island, South Shetland Islands

59%
Gielwanowska I., Bochenek A., Gojlo E., Gorecki R., Kellmann W., Pastorczyk M., Szczuka E.
Polish Polar Research
|
2011
|
tom 32
|
nr 2
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