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Gentiana asclepiadea L. is a montane flowering plant species that has a very limited lowland distribution in Poland. The only existing lowland station that is known occurs in the Katowice-Muchowiec (Silesian Upland). In this paper a second station from the Silesian Upland in the Mikołów-Jamna area is described. A single cluster of rare albiflora form was observed within the newly discovered population. Information about the status and distribution of the Willow Gentian in Poland is also given.
We studied the phylogeography of Swertia tetraptera Maxim, which is an annual herbaceous plant endemic to the Qinghai-Tibetan Plateau (QTP), by sequencing one intergenic chloroplast spacer, trnL-trnF (773 bp). The sampling design included 35 populations and 399 individuals, and spanned the entire distribution of the species. Forty-four haplotypes were characterized, and one of them was widely distributed in all of the populations. The level of differentiation among the populations studied was relatively low (GST = 0.128). Estimates of NST -GST for populations of S. tetraptera indicated that no phylogeographical structure exists, which was supported by the distribution of haplotypes. The neutrality test, mismatch distribution and a ‘star-like’ genealogy all suggested that this species experienced population expansion. According to the number of rare haplotype and geological evidence, this study suggested that two potential refugia existed during the last glaciation: the first refugium was identified in a restricted semi-continuous area around the eastern margin of the plateau; the second refugium was located in the central of QTP. In fact, the findings of our study are somewhat similar as the third phylogeographical structure occurring in the QTP, that is, alpine plants have refugia not only in the edge area but also in the Plateau platform. However, the location of plateau edge and plateau platform refugia is very different among them due to the difference of species-specific characteristic such as distributional range and life history traits.
Various explants from 30-day-old seedlings of Centaurium erythraea Rafn were evaluated for their morphogenetic capacity under in vitro culture conditions. Shoot formation from shoot tip explants was achieved mainly through adventitious bud differentiation. The highest number of shoots (up to 43.3 ± 2.2 from a single shoot tip) was obtained on Murashige and Skoog medium (MS) supplemented with indole-3-acetic acid (IAA) (0.57 μM) and 6-benzylaminopurine (BAP) (4.4 μM). Adventitious shoot regeneration was also achieved through organogenesis from calluses obtained from hypocotyls, cotyledons, roots and leaves on MS medium containing IAA (2.85 μM) and BAP (0.88 μM). Significant differences were noted between explant types in their effects on shoot regeneration. In the primary culture, the best response was obtained either from calluses derived from roots or leaves (44.4 ± 4.5 and 40.2 ± 6.0 shoots per callus, respectively). The number of subcultures of inoculated calluses affected both the multiplication rate (the number of shoots/explant) and shoot morphology (the frequency of shoot hyperhydricity). Shoots rooted with the frequency of 94-100% after culture on MS medium without growth regulators. Plantlets were successfully acclimatized (97%) under high relative humidity and then moved to the greenhouse.
A study of Gentiana cruciata L. (Gentianaceae), Gymnadenia conopsea (L.) R.Br. (Orchidaceae) and Luzula pedemontana Boiss. et Reut. (Juncaceae) showed differences in the number and characteristics of critical stages in ovule and seed development. The shared critical stages explain the general direction of the formation of reproductive structures and surrounding tissues. The taxon-specific critical stages may have different implications in a given species: they may (1) verify that the ovule belongs to a specific type, (2) indicate their lability in different taxa with the same ovule type, or (3) coincide in species with various ovule types.
A protocol was developed for high frequency and low cost of in vitro shoot proliferation and ex vitro rooting of Eustoma grandiflorum (Gentianaceae) on solid medium. Shoot tips as explants were cultured on Murashige and Skoog (MS) medium enriched with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) (0.00, 0.01, 0.10 and 1.00 mg l–1) and 6-benzylaminopurine (BAP) (0.00, 0.50, 2.00 and 5.00 mg l–1). Three culture media systems (solid, liquid and double-phase) were applied. None of the explants cultured on liquid and double-phase media resulted in live plant production. Maximum axillary shoot number (54.45) was recorded in the plantlets treated with 0.10 mg l–1 2,4-D in combination with 5.00 mg l–1 BAP. Treatment of 0.01 mg l–1 2,4-D along with 0.50 mg l–1 BAP produced maximum node number and internode length. Some shoots produced on medium containing plant growth regulators (PGRs) were rooted in soil. The largest number (5.50/plantlet) and longest length of root (7.75 cm/plantlet) were obtained in ex vitro condition on the base of shoots produced in culture medium enriched with 0.10 mg l–1 2,4-D along with 0.50 mg l–1 BAP. The combination of 1.00 mg l–1 2,4-D and 0.50 mg l–1 BAP was found to be the most suitable PGRs for obtaining the highest callus weight. The most fresh weight was calculated from plantlets grown on the medium containing 0.10 mg l–1 2,4-D along with 5.00 mg l–1 BAP. Maximum dry weight was obtained in free-PGRs medium. About 90% of the rooted plantlets were established successfully in cultivation beds. Acclimatized plants were morphologically similar to the mother plants.
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Bukiety
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2002
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nr 2
44-45
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