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PL
Celem pracy było określenie wpływu wielkości nasion na przebieg i rezultaty procesu ekspandowania nasion w strumieniu gorącego powietrza w pionowym przewodzie pneumatycznym. Analizy problemu dokonano na podstawie wyników symulacji komputerowej procesu dla dwóch klas ziarnowych tego samego gatunku nasion. Wykazały one, że dla każdej klasy ziarnowej należy odrębnie ustalać optymalne, z punktu widzenia jakości produktu, parametry procesu.
EN
The purpose of the study was to determine the impact of seed size on the course and results of the seed expansion process in a stream of hot air in a vertical pneumatic tube. The problem analysis was done based on the results of a computer simulation of the process for two grain classes of the same grain type. It was found that for each grain class it is necessary to establish separately the process parameters that would be optimal from the point of view of the quality of the product.
EN
There is little consistent evidence for evolutionary associations from seed production to seedling fitness. In this study, 20 species of Rhododendron genus were selected from subtropical forests of southwest China; the life-history functional traits such as the seed size, seed number per twig, germination traits, dispersal and seedling survival were investigated, the ecological relationships among them were tested and the advantages of small-seeded species were discussed. The results show that the quantitative parameters of germination, such as the germination rate, potential, and index are positively correlated with seed number produced per stem, while temporal parameters, such as germination peak timing and duration are positively correlated with seed size. The two results indicate that different Rhododendron species with different seed sizes and relative seed number can deal with varying environments according to spatial dispersal or time dispersal, respectively, and the advantages of smaller seeds in the aspect of sprouting vigour, dispersal ability and seedling survival may lay the foundation for the establishment of small-seeded plants in the forest.
EN
As the main predator and disperser of seeds, rodents play an important role in the process of vegetation regeneration by adopting different foraging and hoarding strategies in forest ecosystems. Infrared automated detection cameras and seed-tagging methods were used to understand the effects of rodents on seeds in natural environments. We chose the dominant species Apodemus peninsulae (Korean field mouse) as the focus of this study, and seeds of the three species Pinus koraiensis, Corylus mandshurica and Quercus mongolica were released and tracked in a temperate forest in northeast China. The results showed that approximately 80% of the seeds were manipulated by A. peninsulae, 15.1% of the seeds were used as food, 20.4% of the seeds were handled after feeding, 41.3% of the seeds were handled during storage, and 23.3% of the seeds remained intact. In addition, A. peninsulae preferred Q. mongolica (85.3%) and P. koraiensis (85.6%) over C. mandshurica (59.2%). The rodents frequently hoarded seeds from every species in many small, close-range, widely dispersed, single scatter-hoarded caches around the seed station. Most caches were dispersed approximately 2–4 m from the seed station. The results indicated that A. peninsulae adopted significant discriminatory processing strategies for predation, consumption, dispersal and hoarding of the different seeds of sympatric species. Seed size, proportion of kernel mass, nutrient content, and hull thickness characteristics affected the scatter-hoarding decision processes.
EN
Theoretical and field studies on seed size and plant abundance relationship have been conducted in various communities. However, inconsistent patterns have emerged from these studies, and still little is known about alpine meadows. Here we identified four models and their predictions: the seed size/number trade-off model (SSNTM), the succession model (SM), the spatial competition model (SCM), and the triangle model (TM), in order to assess the relationship between seed size and abundance in alpine meadows, and to elucidate underlying mechanisms. The study site was situated on the eastern Qinghai-Tibetan Plateau at 3500 m above sea level. From 1999 through 2001, two indices of plant abundance (aboveground biomass and density) were simultaneously measured in 45 quadrates (0.25 m²). Data for 101 plant species (mostly Cyperaceae, Poaceae, Asteraceae, Ranunculaceae and forbs) showed that seed size is like log normal distributed, and it slightly skewed in smaller-sized seeds. The SSNTM, the TM, the SM and the SCM models were not supported in this alpine meadow, and the relationship between seed size and abundance was always positive (although in some samples, the relationship was not significant). The positive correlation between seed size and abundance observed for some grassland communities was also demonstrated in the alpine meadow. It suggests that seed size depends on the plant growth form, but the biomass-density relationship is inconsistent with previous studies. This suggests that the measure of abundance used in these studies is not the only reason for inconsistency of seed size.
EN
Loiseleuria is a monotypic genus of the family Ericaceae. The only species of this genus, L. procumbens, is an arctic-alpine element with a circumpolar distribution, found in the subarctic zone and in mountain ranges located further south. Results of earlier research on the structure of its fruits and seeds (Szkudlarz 2002) suggested that there are some differences between populations from different parts of its natural range of distribution. To verify this hypothesis, seed dimensions in samples from distant localities were compared in this study. The presented results indicate that in populations from Scandinavia seeds are generally shorter than in central Europe.
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2009
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tom 55
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nr 4
15-24
EN
Experiments were carried out in 2006-2008 on Lysimachia vulgaris L. plants from tw natural and one cultivated populations. The following features were determined: mea number of capsules per shoot, mean number of capsules per shoot with respect to thre different levels of fruit localization in the inflorescence, seed breadth, length and germ nability. Mean number of fruits per shoot was significantly higher for cultivated plant in comparison with plants growing in natural populations. Both cultivated plants an those growing in natural habitats formed significantly more fruits in the middle part c the inflorescence in comparison with bottom and top parts of the inflorescence. Mea number of seeds per capsule depended on the fruit localization in the inflorescenc and was the highest for capsules located in the middle part of it. The seed size and gei minability after the final count depended on seed localization on a plant. The highes germinability was observed for seeds of cultivated plants produced in the middle par of the inflorescence.
PL
Badania prowadzono prze trzy sezony wegetacyjne w latach 2006-2008 na roślinach Lysimachia vulgaris L. z dwóch populacji naturalnych oraz rosnących w uprawie na jednej plantacji. Określono następujące cechy roślin: średnią liczbę owoców na pędzie, średnią liczbę owoców zawiązanych na jednym z trzech wydzielonych odcinków pędu owocującego, szerokość i długość nasion oraz energię i zdolność kiełkowania nasion z trzech ocenianych poziomów owocowania. Średnia liczba owoców na pędzie była istotnie wyższa u roślin uprawianych w porównaniu z roślinami z populacji naturalnych. Zarówno rośliny uprawiane, jak i rosnące w warunkach naturalnych wykształciły istotnie więcej owoców na rozgałęzieniach ze środkowego odcinka kwiatostanu w porównaniu z odcinkiem dolnym i górnym. Średnia liczba nasion w owocu zależała on położenia owocu na roślinie i była najwyższa dla owoców zawiązanych w środkowej części kwiatostanu. Wielkość oraz zdolność kiełkowania nasion zależała od położenia nasion na roślinie. Najlepiej kiełkowały nasiona z roślin uprawnych wykształcone w środkowej części kwiatostanu.
EN
Theoretical and field studies on seed size and plant abundance relationship have been conducted in various communities. However, inconsistent patterns have emerged from these studies, and still little is known about alpine meadows. Here we identified four models and their predictions: the seed size/number trade-off model (SSNTM), the succession model (SM), the spatial competition model (SCM), and the triangle model (TM), in order to assess the relationship between seed size and abundance in alpine meadows, and to elucidate underlying mechanisms. The study site was situated on the eastern Qinghai-Tibetan Plateau at 3500 m above sea level. From 1999 through 2001, two indices of plant abundance (aboveground biomass and density) were simultaneously measured in 45 quadrates (0.25 m[^2]). Data for 101 plant species (mostly Cyperaceae, Poaceae, Asteraceae, Ranunculaceae and forbs) showed that seed size is like log normal distributed, and it slightly skewed in smaller-sized seeds. The SSNTM, the TM, the SM and the SCM models were not supported in this alpine meadow, and the relationship between seed size and abundance was always positive (although in some samples, the relationship was not significant). The positive correlation between seed size and abundance observed for some grassland communities was also demonstrated in the alpine meadow. It suggests that seed size depends on the plant growth form, but the biomass-density relationship is inconsistent with previous studies. This suggests that the measure of abundance used in these studies is not the only reason for inconsistency of seed size.
EN
Experiments to determine the effect of seed size, watering interval and defoliation on growth and dry matter attributes of seedlings of shea butter tree were conducted at Makurdi, Nigeria, from July 2010 to April, 2012. In the first experiment, treatments were made up of three seed size categories described as small (5-10g), medium (11-15g) and large (16-20g) and three watering intervals of 3, 6 and 9 days. In the second experiment, treatments comprised three watering intervals of 3, 6 and 9 days and three levels of defoliation – 0, 50 and 100%. In both experiments, factorial combinations of the treatments were laid out in completely randomized design (CRD) and replicated three times. Results of analysis of variance showed that in the first experiment seed size significantly influenced root length with the medium and large seeds producing seedlings with comparatively longer roots than the small seeds. The most frequently watered seedlings (3 and 6 days) produced more leaves than those watered less frequently (9 days). Seed size influenced dry weight of root and total (whole plant) dry weight with the medium and large seeds recording significantly higher values than the small seeds. Watering interval however did not significantly influence any of the other traits. Seed weight exerted significant influence on amount of dry matter partitioned to the stem and the root. More dry matter was partitioned to the stem by the small seeds. Conversely, medium and large seeds allocated more dry matter to the root than to the stem. In the second experiment, defoliation level only influenced total fresh weight, dry weight of root and total dry weight in favour of plants with half their leaves removed. None of the traits examined were significantly influenced by watering regime. Interaction between defoliation level and watering regime significantly influenced total fresh weight, dry weight of root and total dry weight. Generally seed size had more influence on seedling characters than watering interval. Seedlings also demonstrated remarkable ability to overcome effects of defoliation.
PL
Przygotowanie wartościowego i kwalifikowanego materiału siewnego marchwi i pietruszki wymaga wiedzy z zakresu podstawowych właściwości fizycznych nasion gatunku podstawowego oraz pozostałych komponentów mieszaniny ziarnistej (zanieczyszczenia, nasiona innych gatunków roślin itp.). Znajomość cech fizycznych nasion wymagana jest ponadto przy doborze i ustalaniu parametrów techniczno-technologicznych procesów czyszczenia i separacji czy innych zabiegów ukierunkowanych na uszlachetnianie materiału siewnego. W pracy zestawiono i porównano wybraną grupę właściwości fizycznych oraz skład granulometryczny nasion marchwi i pietruszki pozyskanych w zbiorze kombajnowym. Wykazano zróżnicowanie niektórych cech fizycznych nasion marchwi i pietruszki, przy czym dotyczyło to głównie charakterystyk masowych (gęstość w stanie zsypu i gęstość utrzęsiona) oraz wymiarów geometrycznych najbardziej licznych i reprezentatywnych frakcji wymiarowych. Analiza składu granulometrycznego nasion obu warzyw, przeprowadzona równolegle na przesiewaczu sitowym i wibracyjnym, wykazała, że najbardziej liczną i reprezentacyjną z punktu widzenia wartości siewnej grupą były nasiona marchwi o wymiarach 1,3, 1,5 i 1,7 mm. Łączna ilość tych trzech frakcji stanowiła około 78% ogółu oczyszczonych wcześniej nasion. W przypadku nasion pietruszki najbardziej liczną grupę stanowiły nasiona o wymiarach. 1,1 i 1,3 mm, a ich sumaryczny udział w ogólnej masie nasion wyniósł około 84,46.
EN
Preparation of valuable and certified carrot and parsley seed material requires the knowledge of basic physical properties of seeds of the basic species components and of the other components of a mixture (dirt, seeds of other plant species, etc.). Knowledge of the physical charac-teristics of the seeds is also required in the selection and setting of technical and technological pa-rameters of cleaning and separation or other treatments aimed at refining seed. This paper summa-rizes and compares selected group of physical properties and particle size distribution of carrot and parsley seeds obtained in combine harvest. A variation was demonstrated in certain physical charac-teristics of the carrot and parsley seeds, and the characteristics are mainly related to the mass (bulk density and shaken density) and the geometric dimensions of the most numerous and representative dimensional fractions. Particle size distribution analysis of both vegetable seeds, carried out in parallel on a sifter and a vibrating sieve, showed that the largest and the most representative from the viewpoint of sowing value group of seeds were carrot seeds in the sizes of: 1.3, 1.5 and 1.7 mm. The total amount of these three sizes accounted for approximately 78% of pre-treated seeds. In the case of seeds of parsley were most numerous group were seeds of the two sizes of 1.1 and 1.3 mm, and their combined share in the total weight of the seeds was approximately 84,46%..
EN
Milla biflora Cav, is one of six species of this genus reported to be present in Mexico. To determine the present and potential seed production of this plant, the following characteristics were studied: the number of flowers per scape, the frequencies of scape with defined number of flower per scape, the conversion of flowers into capsules, the capsule size, seed numbers, average seed size per capsule. Samplings were taken from the natural stands and evaluation of the respective attributes was done in plants growing in germplasm collection belonging to the University UPAEP. The number of flowers ranged from 1 to 10 per scape, with 90.6% of scapes giving from 1 to 6 flowers. The capsules were formed from flowers in the following proportions: in scapes with one flower - 13.64%, in scapes with 3 flowers - 48.21%, in scapes with four or more flowers - 60%; 67.80 of capsules gave from 60 to 140 seeds; 45% of seeds had the average size from 1.81 to 2.20 mg. The mean weight of 1000 seeds was 1937.2 mg. The seeds germinated during 7 days in water, in 88 to 100%. The plant emergence from soil sown seeds ranged from 41.4 to 1OO %. The seeds have not lost the germination ability after 2 years of storage at room conditions.Milla biflora Cav, is one of six species of this genus reported to be present in Mexico. To determine the present and potential seed production of this plant, the following characteristics were studied: the number of flowers per scape, the frequencies of scape with defined number of flower per scape, the conversion of flowers into capsules, the capsule size, seed numbers, average seed size per capsule. Samplings were taken from the natural stands and evaluation of the respective attributes was done in plants growing in germplasm collection belonging to the University UPAEP. The number of flowers ranged from 1 to 10 per scape, with 90.6% of scapes giving from 1 to 6 flowers. The capsules were formed from flowers in the following proportions: in scapes with one flower - 13.64%, in scapes with 3 flowers - 48.21%, in scapes with four or more flowers - 60%; 67.80 of capsules gave from 60 to 140 seeds; 45% of seeds had the average size from 1.81 to 2.20 mg. The mean weight of 1000 seeds was 1937.2 mg. The seeds germinated during 7 days in water, in 88 to 100%. The plant emergence from soil sown seeds ranged from 41.4 to 1OO %. The seeds have not lost the germination ability after 2 years of storage at room conditions.
PL
Milla biflora Cav. jest jednym z sześciu gatunków z tego rodzaju występujących w Meksyku. W celu określenia aktualnej i potencjalnej produkcji nasion przeprowadzono następujace obserwacje: ilość kwiatów na pędzie, częstotliwość występowania pędów z określoną ilością kwiatów, rozwój torebek nasiennych z kwiatów, ilość nasion w torebce i średnia wielkość nasion w torebce nasiennej. Próbki pobierano ze środowiska naturalnego oraz z kolekcji. Przeprowadzono ocenę wszystkich powyższych cech na roślinach znajdujących się w kolekcji germoplazmy roślin bulwiastych. Ilość kwiatów na pędzie wynosiła od 1 do 10; 90.6% pędów tworzyło 1 do 6 kwiatów. Zamiana kwiatów na torebki nasienne wystąpiła u 13.6% pędów z 1 kwiatem, u 48.2% pędów z 3 kwiatami i u 60% pędów z 4 lub więcej kwiatami. 67.8% torebek nasiennych dało po 60 do 140 nasion. Średnia masa 45% nasion wynosiła od 1.81 do 2.2 mg. Średnia masa 1000 nasion wynosiła 1937.2 mg. Nasiona kiełkowały w wodzie w ciągu 7 dni w 88 do 100%. Kiełkowanie nasion wysianych do gleby wynosiło od 41.4 do 100%. Nasiona mogą być przechowywane w warunkach laboratorium 2 lata bez strat w sile kiełkowania.
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