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1

The maternal effect of germination of Maticaria maritima achenes

100%
Kucewicz M.
Acta Physiologiae Plantarum
|
1999
|
tom 21
|
nr 3 suppl.
2
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Wpływ zagęszczenia na płodność i cechy morfologiczne roślin tobołków polnych (Thlaspi arvense L.)

100%
Kucewicz M.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2002
|
tom 481
|
nr 2
W celu zbadania wpływu zagęszczenia na płodność osobniczą i populacji oraz niektóre cechy morfologiczne roślin Thlaspi arvense L. przeprowadzono badania wazonowe w warunkach szklarniowych w różnych wariantach zagęszczenia. Na powierzchni 177 cm² stosowano 6 wariantów zagęszczenia (10, 15, 20, 40, 50 i 60 osobników w wazonie). Począwszy od najniższego zagęszczenia notowano spadek płodności osobniczej aż do uzyskania stałej wartości przy zagęszczeniu 50 i 60 osobników w wazonie. Reprodukcja generatywna populacji przypadającej na jednostkę powierzchni rosła do zagęszczenia 20 osobników w wazonie, tu osiągała wartość maksymalną. Załamanie płodności populacji nastąpiło przy zagęszczeniu między 20 a 40 osobnikami w wagonie. Eksperyment wykazał, że sześciokrotny wzrost zagęszczenia (60 osobników w wazonie) w stosunku do zagęszczenia wyjściowego (10 osobników w wazonie) spowodował spadek płodności ogólnej zaledwie o 20%. Wybrane cechy morfologiczne (liczba rozgałęzień i wysokość) w różny sposób reagowały na wzrost zagęszczenia. W miarę wzrostu zagęszczenia następowało znaczne różnicowanie wysokości osobników. Wzrost zagęszczenia powodował ponadto upraszczanie budowy pędu. Obserwowano szerszy zakres badanej cechy, jednak przeciętna liczba wytwarzanych bocznych rozgałęzień konsekwentnie malała.
3

Mapping and stimulation of memory in the human brain – can engrams be electrically enhanced?

100%
Kucewicz M.
Acta Neurobiologiae Experimentalis
|
2018
|
tom 78
|
nr Suppl.1
Direct electrical stimulation of the human brain can elicit sensory and motor perceptions as well as recall of memories. Stimulating higher order asso‑ ciation areas of the lateral temporal cortex in par‑ ticular has been reported to activate visual and au‑ ditory memory representations of past experiences. We hypothesized that this effect could be utilized to modulate memory processing. Recent attempts at memory enhancement in the human brain have focused on the hippocampus and other mesial tem‑ poral lobe structures, with a few reports of memo‑ ry improvement in small studies of individual brain regions that have not been reproduced. We investi‑ gated the effect of stimulation in four brain regions thought to support declarative memory: hippocam‑ pus, parahippocampal neocortex, prefrontal cortex and temporal cortex. A classic verbal memory task was used to assess the effect of bipolar 50 Hz stimu‑ lation during encoding of word lists on subsequent free recall in human patients implanted with in‑ tracranial electrodes. We found enhanced recall of words from lists with electrical stimulation in the lateral temporal cortex, but not in the other three brain regions tested. This selective enhancement was observed on the level of individual subjects, sub‑ jects stimulated in the temporal cortex, and across the four brain regions studied. In effect, more words were remembered with than without stimulation in the lateral temporal cortex. Stimulation targets in the other brain regions had a negative effect on memory compared to targets in the temporal cortex. These differential behavioral effects were paralleled by modulation of neural activities in the high gam‑ ma frequency band (60‑120 Hz) during memory en‑ coding. These activities were proposed to reflect co‑ ordinated firing of neuronal assemblies – the hypo‑ thetical neural substrate for engrams. We conclude that electrical stimulation in specific brain areas can modulate neural processes induced during encoding of word engrams and enhance their recall. Gamma frequency activities provide a useful biomarker to map memory engrams and guide human brain stim‑ ulation.
4

Effect of density on the fertility and morphometric chracters of Thlaspi arvenese L.

88%
Kucewicz M.
Acta Physiologiae Plantarum
|
2001
|
tom 23
|
nr 3 suppl.
5

The effect of storage conditions on the germination of Vicia hirsuta L., Vicia angustifolia L. and Vicia tetrasperma (l) Schreb. seeds

63%
Kucewicz M., Holdynski C.
Acta Physiologiae Plantarum
|
2003
|
tom 25
|
nr 3 suppl.
6

The ecological importance of seed dimorphism in corn spurry (Spergula arvensis L.). 2. The effects of nitrate concentrations and temperature on seed germination

63%
Kucewicz M., Gojlo E.
Polish Journal of Ecology
|
2013
|
tom 61
|
nr 4
Spergula arvenis produces two types of seeds that differ in the absence (non papillate, NP) or presence (papillate, P) of papilla on the seed coat. Corn spurry inhabits cultivated soils and ruderal fields and usually encounters substantial variations in soil nutrients. The objective of this study was to determine the effects of nitrate concentrations and temperature (10–30°C) on the germination of heteromorphic seeds. NP and P seeds were characterized by different nitrate optima, dormancy-breaking temperature and initial germination times. NP seeds germinated better and faster than P seeds. NP seeds germinated at all nitrate solutions and all temperatures. NP seeds responded to 5 mM nitrate concentration at 15, 20 and 30°C. In 25 and 50 mM KNO₃ solution, the germination was relatively high and leveled out at a wider temperature range (15–30°C). The highest germination of NP seeds was at 25°C (25, 50 mM KNO₃). NP seeds began to germinate on the second day of the germination test at 15–30°C (in 25 mM KNO₃ solution) and at 20–30°C (in 50 mM KNO₃ solution). The germination percentage of P seeds was lower than NP seeds under identical conditions. P seeds in water failed to sprout at any of the applied incubation temperatures. Seeds incubated in low and medium nitrate concentrations did not germinate or germinated weakly at all temperatures. Seed dormancy was released in solutions with high nitrate levels incubated at 10–25°C. The highest germination of P seeds was at 50 mM solution and at 15°C. Under these conditions, the P seeds germinated the most (reaching 43%), with the initial germination being observed on experimental day 3,7. P seeds had more requirements for germination than NP seeds. However, in 50 mM KNO₃ solution the range of temperatures over which these seeds were able to germinate was the same regardless of seed type. Nevertheless, the percentage of NP germinants was still much higher. The different requirements for germination of NP and P seeds may result in the production of two offspring cohorts that differ in response to nitrate levels in the soil, population density and temperature conditions. Most likely, this germination strategy is an important mechanism of ecological adaptation that enables the survival of S. arvensis plants in an unpredictable environment.
7

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

63%
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.
8
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Germination of Matricaria maritima subsp. Inodora [L.] dostal [scentless mayweed] achenes depending on their maturity and position on the mother plant

63%
Kucewicz M., Holdynski C.
Journal of Plant Protection Research
|
2003
|
tom 43
|
nr 2
9
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Generative reproduction and external conformation of Echinochloa crus-galli [L.] P. Beauv. plants under various density conditions

63%
Kucewicz M., Holdynski C.
Journal of Plant Protection Research
|
2003
|
tom 43
|
nr 1
10

Employment of in vitro cultures in Chamaedaphne calyculata (L) Moench protection

51%
Zrobek-Sokolnik A., Kucewicz M., Holdynski C.
Acta Societatis Botanicorum Poloniae
|
2010
|
tom 79
|
nr Suppl.1
11

Ecophysiological conditions of germination of barnyard grass [Echinochloa crus-galli [L.] P. Beauv.] diaspores

51%
Kucewicz M., Holdynski C., Gojlo E.
Journal of Plant Protection Research
|
2006
|
tom 46
|
nr 1
73-84
The aim of the study was to investigate the effect of some different environmental conditions prevailing during the development and ripening of Echinochloa crus-galli diaspores on their germination. Some seeds were tested in the autumn the same year, whereas others were divided into two groups: dispersed seeds and seeds within the inflorescence. Then the seeds of both groups were buried. After eight-month stratification in the soil, the diaspores were tested under the same conditions as the samples examined in the autumn. The seeds tested in the spring germinated faster than those tested in the autumn. Also the germination capacity of barnyard grass caryopses examined in the summer was almost twofold higher than the germination capacity of those examined in the autumn. Both autumn and spring tests revealed that the harvest time affected germination. The seeds obtained in the second half of August and at the beginning of September (in the middle of the growing season) were characterized by a higher germination capacity than the caryopses collected at the beginning and the end of the reproduction period. The results show that the germination capacity and rate were not influenced by the place of origin, habitat conditions and accompanying plants. It was found in spring tests that germination depended on the kind of dissemination unit stored in the soil. After eight-month soil stratification, dispersed caryopses germinated by approx. 20% better than those stored with a part of the inflorescence.
12
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The effect of achene heteromorphism on germination in the shaggy soldier [Galinsoga ciliata (Rafin) S.F. Blake]

51%
Kucewicz M., Wardzynska A., Zrobek-Sokolnik A.
Acta Agrobotanica
|
2011
|
tom 64
|
nr 1
Heteromorphic achenes are formed within each capitulum of Galinsoga ciliata (Rafin) S.F. Blake. We examined (1) the effects of the duration of dry storage on germination and (2) the effect of burial in soil on viability and germination of heteromorphic diaspores. Fresh harvested peripheral achenes remained dormant, while central achenes germinated at 60%. Both achene types became non-dormant after one month of dry storage. In successive months of dry storage, peripheral achenes demonstrated a higher germination percentage than central achenes. The peripheral and central achenes showed similar temperature requirements during dry storage. A similar germination pattern was observed in both achene types, with a germination peak in March (96% of peripheral achenes at 12, 26 and 34oC; 90% of central achenes at 26 and 34oC). The germination capacity deteriorated over time. After 19 months of dry storage, both achene morphs failed to germinate at 12oC. At a 26o and 34oC, the same group of achenes continued to germinate at a relatively high level. After six and seven months of soil storage, 90-95% of both achene types remained alive. Dimorphic achenes were characterized by similar germination percentage (89-99%) at all temperature intervals, whereas peripheral achenes exhumed in May were the fastest to germinate. After 18 months of storage in soil (successive growing season), most of the harvested achenes were dead. The studied achenes did not form a permanent seed bank.
13
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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

51%
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.
14
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The effect of achene heteromorphism on progeny traits in the shaggy soldier [Galinsoga ciliata (Rafin) S. F. Blake]

51%
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.
15

Micropropagation of Chamaedaphne calyculata (L.) Moench by direct shoot organogenesis

45%
Zrobek-Sokolnik A., Slipiko A., Kucewicz M., Milewicz M., Holdynski C.
Polish Journal of Natural Sciences
|
2011
|
tom 26
|
nr 3
The objective of this experiment was to investigate the effect of various concentrations of sucrose, 6-(γ,γ-dimethylallylamino)-purine (2iP) and pH values of Lloyd’s and McCown’s medium (1981, WPM) on the induction of lateral shoot growth in Chamaedaphne calyculata (L.) Moench. The explants were 2–3 cm nodal sections without the apex, with preserved leaves, from plants grown in vitro. The highest regenerative capacity was observed in culture media without cytokinin, with 58 mM sucrose content and pH 5.0. The lowest capacity for shoot organogenesis was reported in media with pH 5.6 with a higher sucrose content (88 mM) and 25 μM of 2iP. 80% of rooted explants were successfully transferred to ex vitro conditions. The survival rate of plantlets reached around 60% after three months of greenhouse cultivation.
16

Czynniki gwarantujące sukces na rynku opakowań

44%
Kucewicz M.
Przegląd Papierniczy
|
2014
|
tom 70
|
nr 02
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