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The number and the weight of seeds per capsule were assessed along with the individual seed mass in cowslip plants of various origin, grown in plots with differing plant spacing. The potential seed productivity (the number of ovules per ovary) and the real seed yield (the number of seeds per capsule) were determined for the cultivated plants and the effect of seed origin and gibberellic acid (GAj) on germination capacity was evaluated under field conditions. The mean seed number per cap­sule for plants growing at the 40 x 30 spacing ranged from 31.2 to 64.4, whereas for the 30x15 spacing it ranged from 37.2 to 60.6 seeds per capsule, depending on the year of study and the flo­wer morph type. The seed number per capsule and the individual seed mass turned out to be traits dependent in a statistically significant way on the origin of seeds used to start the cultivated po­pulations. Plants from populations 2 and 3 produced the heaviest seeds (mean = 1.10 mg and 1.14 mg). The differentiation in the number of seeds per capsule and in the individual seed mass in fruits coming from the same scape was statistically significant. The mean number of ovules per ovary ranged from 64.8 to 71.0 and the mean seed number per capsule ranged from 46.2 to 51.7. The number and percentage of germinated .seeds ranged from 6 (4.0%) to 48 (32.0%), depending on the seed origin. Seeds treated with GA3 germinated in 36.0 to 813%.
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.
Given the finite resources of seed production, a trade-off between seed weight and number was expected. However, it still remains unclear how the seed weight-number trade-off changes if there are some mechanisms to enhance resource acquirements during the fruit developments. Sinopodophyllum hexandrum presents furled leaves in flowering time but unfurled leaves in fruiting time, which is considered to enhance the photosynthates to fruit development. To determine the relationship between seed weight and number of S. hexandrum, we examined the altitudinal variations and the relationship between seed weight and number in the fruits from 27 populations of in 2009 and 2010. Our results showed that, along the altitudinal gradient, seed weight decreased significantly but seed number increased insignificantly, indicating that the selective pressure on seed production might come from seed dispersal in high altitude populations. There was no significant relationship between seed weight and number in most populations, but an inverse relationship was found between seed weight and number when the data from all populations were pooled, indicating the seed weight-number trade-off and resource limitation of seed production in S. hexandrum on species level. We suggested that the two unfurled leaves of S. hexandrum might contribute to the resources allocated to the fruit development via enhancing photosynthates, which might mask the seed weight-number trade-off on population level to some degree.
Badano zależności między morfologią kwiatów marchwi męskosterylnych i męskopłodnych linii hodowlanych i zdolnością do wytwarzania nasion. W badanej populacji męskosterylnych roślin marchwi kwiaty charakteryzowały się przekształceniem pręcików w dodatkowe struktury płatkopodobne o różnych kształtach. W niektórych pylnikopodobnych strukturach kwiatu stwierdzono obecność degenerującej tkanki sporogennej. Wyniki obserwacji i analiz mikroskopowych pozwalają twierdzić, że na obniżenie produktywności nasion linii hodowlanych marchwi mogły mieć wpływ defekty i nieprawidłowości morfologiczno-funkcjonalne kwiatów roślin ojcowskich oraz matecznych. Degeneracja pyłku, brak warstwy endotecjum, decydującej o otwieraniu się pylnika, wzrost łagiewek pyłkowych po zewnętrznej powierzchni szyjki słupka należały do najczęściej występujących ograniczeń w ilości pyłku aktywnego w zapłodnieniu. Cechy męskosterylnych roślin matecznych utrudniające proces zawiązywaniu nasion to: zielona barwa płatków, redukcja miodników, deformacje słupków, brak zalążni, degeneracja zalążków lub zarodków. Najmniej nasion wytworzyły rośliny z licznymi deformacjami morfologicznymi znamion słupka i miodników. Kwiaty roślin męskosterylnych o białych płatkach, dużych miodnikach i wysokich, podwójnych słupkach wydały najwięcej nasion, gdyż były prawdopodobnie najbardziej atrakcyjne dla zapylających owadów.
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.
Results of statistical analysis of 112,136 seeds extracted from 376 fir Abies alba Mill. cones are given. The cones were collected in the Babia Góra National Park and its surroundings, and in the Gorce N.P. The analysis concerns a total number of seeds in a cone, number of viable and infertile seeds, and also seeds damaged by Resseliella piceae Seitn. The Kоlmogorov-Smirnov's test for general characteristics of variables was used. This test has shown that number distributions of mentioned seed groups were symmetrical. Also, coefficients of linear and partial correlation, as well as equations of multiple regression line were calculated for distinguished seed groups. Values of coefficients of the equations of multiple regression line in all studied areas were statistically significant at 0.001 level. It was stated that there exists a positive correlation between the total number of seeds in a cone and their damage by R. piceae.
Badania prowadzono na kępach kosaćców rosnących w otwartym polu: kosaćca trawiastego (I. graminea L.), kosaćca żółtego (I. pseudacorus L.) i na dwóch formach A i B kosaćca syberyjskiego (Iris sibirica L.). Uzyskane owoce i nasiona były efektem zapylenia swobodnego. Biometryczne pomiary torebek nasiennych, liczby nasion i masy 1000 nasion pokazały, że największe torebki i najcięższe nasiona ma kosaciec żółty. Odnotowano istnienie wyraźnej zależności pomiędzy wielkością torebek a liczbą nasion. Stała korelacja pomiędzy obiema cechami we wszystkich latach, bez względu na pogodę, występowała u kosaćca trawiastego. Ilość opadów wpływała różnie na wykształcenie nasion u badanych gatunków kosaćców.
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