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The aim of the experiment was to determine suitable substrate type and optimal plant size for transfer of plantlets from in vitro to ex vitro under experimental outdoor conditions. Tests focused on the effect of substrate type (muddy and sandy) and starting size of plantlets gained through in vitro seed germination (0-3, 3.1-5,5.1-6, 6.1-10 cm) on plant growth. Three parameters (fresh weight, length, and the number of leaves) were compared to evaluate growth. Basic water parameters in experimental water tanks were regularly measured (pH, temperature, electrical conductivity, shadow intensity) and controlled to reach similar conditions to those in the natural habitat of this species. Overwintering was studied in a cellar with newly defined size categories (<6, 6.1-8, 8.1-10, 10.1-12, 12.1-15 cm). Both substrate type and starting size of plantlets significantly impacted growth. Plantlets grew better in the muddy substrate while a 100% success rate of rooting was gained with a starting size of 6.1-10 cm in both substrates. The biggest increase in fresh weight was observed with a starting size of 3.1-5 cm and 5.1-6 cm in both substrates. The greatest increase in fresh weight was observed in plants with a starting size of 3.1-5 cm in the muddy substrate (more than 95% increase). The best overwintering results were gained in the 6.1-8 cm size category.
Shoot tips of Tibouchina urvilleana Cogn. were cultured 4 weeks in vitro in modified Murashige and Skoog (MS) [1962] medium supplemented with growth retardants: paclobutrazol – 0.1, 0.5, 1.0, 5.0 mg·dm⁻³, flurprimidol – 0.1, 1.0, 5.0 mg·dm⁻³, chlorocholine chloride (CCC) – 5.0, 50.0, 250.0 mg·dm⁻³. Explants cultured on the medium without growth substances were used as a control. Rooted microcuttings were transferred to the greenhouse and transplanted into a mixture of 1 peat : 1 perlite, where they were grown for 5 weeks. Plants were then cultivated in a peat substrate during another 5 weeks. Acclimatization of rooted shoots in the greenhouse was affective in 92.5–100%. The survival of plants was lowest when microcuttings were previously cultured on medium with flurprimidol at 5.0 mg·dm⁻³. Cultivation of Tibouchina urvilleana shoots in vitro on media with various growth retardants had a significant effect on the further growth of plants ex vitro. Paclobutrazol and flurprimidol at 5.0 mg·dm⁻³ inhibited very strong growth of plants after 10 weeks of growth ex vitro.
Dirofilariosis caused by the Dirofilaria repens nematodes is widely dispersed in southern Europe, Asia and Africa among dogs, cats, other carnivores and occasionally, humans. The first case of D. repens infection, found in Poland in 2007, concerned humans. In 2009, dirofilariosis was first registered in dogs in 3 focuses in central Poland, Warsaw, Pruszków and Żyrardów, whose range grew considerably with the subsequent identification of D. repens microfilariae in 119 dogs in Warsaw and 18 districts of the Mazowieckie Province. The microfilariae of D. repens were found in blood samples taken from 1588 dogs from all 16 provinces of Poland. D. repens was also recently detected in a mixture of Culex pipiens and Aedes vexans mosquitoes collected in Mazowieckie Province using Real Time PCR. The results of this study confirms the acclimatisation of D. repens on the territory of Poland and a possibility for it to close its life cycle in domestic species of mosquito.
Eucomis species is a valuable plant with both medicinal and horticultural potential. The current study evaluated the role of plant growth regulator (PGR) on growth, phytochemicals, and antioxidant activity in Eucomis autumnalis subspecies autumnalis. Five cytokinins including topolins and benzyladenine (BA) at 2 µM in combination with varying (0–15 µM) concentrations of naphthalene acetic acid (NAA) were tested. In vitro regenerants were acclimatized in the greenhouse for 4 months. Highest number of shoots (9 shoots/explant) was observed with 15 µM NAA alone or when combined with BA. Acclimatized plants derived from the 15 µM NAA treatment had the highest number of roots, largest leaf area and biggest bulbs. While applied PGRs increased the iridoids and condensed tannins in the in vitro regenerants, total phenolics and flavonoids were higher in the PGR-free treatment. Among the in vitro regenerants, 5 µM NAA and 2 µM BA treatments produced the best antioxidant activity in the DPPH (55 %) and beta-carotene (88 %) test systems, respectively. A remarkable carry-over effect of the PGR was conspicuous in the phytochemical levels and antioxidant activity of the 4-month-old plants. In addition to the optimized micropropagation protocols, the current findings present a promising potential for manipulating the type and concentration of applied PGRs to improve phytochemical production and hence medicinal value in E. autumnalis subspecies autumnalis.
The article presents the results of observations in the years from 1998-2002/2003 concerning the adaptation of some plants that come from warmer climatic regions to the weather conditions that are found in Szczecin. A list of species and varieties of trees and shrubs among which no frost damages were observed is presented in table 1.
A rapid clonal propagation method was developed for Centaurea ragusina L. (Asteraceae), a rare Croatian endemic species. Shoots originated from aseptically germinated seeds were used for culture initiation. The highest multiplication rate, 4.6 shoots per explant, was achieved in a 4-week culture period on half-strength Murashige and Skoog medium supplemented with 1.0 µM 6-benzylaminopurine and 2.9 µM gibberellic acid. Excised shoots were rooted on the same basal medium with 2.5 µM indole-3-butyric acid added. Rooted plantlets were successfully transferred to potting soil and acclimatized to outdoor conditions.
The present study reports a high frequency in vitro propagation protocol through apical bud sprouting and basal organogenic nodule formation in shoot tip explants of Decalepis hamiltonii, an endemic and endangered medicinal liana. Among different combinations of plant growth regulators (PGRs) and growth additives, maximum of 8.20 shoots per explant with mean shoot length of 6.54 cm were induced on Murashige and Skoog’s medium (MS) supplemented with 5.0 µM 6-benzyladenine (BA) + 0.5 µM indole-3-acetic acid (IAA) + 30.0 µM adenine sulphate (ADS) through apical bud sprouting. On single cytokinin treatment explants did not exhibit good multiplication but showed nodulation (N₁) from the basal cut end similar to cytokinin–auxin combination (N₂). Between two types of nodular tissues, N₂ was proved to be better for maximum shoot regeneration (15.40 shoots per explant) and shoot length (4.56 cm) when cultured on MS medium supplemented with 5.0 µM BA, 0.5 µM IAA, 30.0 µM ADS and 1.0 µM gibberellic acid (GA₃). Microshoots were efficiently rooted on half-strength MS medium supplemented with 2.5 µM α-naphthalene acetic acid (NAA). After successful acclimatization in Soilrite, 95.10 % plantlets were survived in field conditions. Histological investigation proved useful in ascertaining the callogenic nature of the regenerating nodular tissue formed at the basal cut end of shoot tip explant. Acclimatized plantlets were studied for the estimation of chlorophyll and carotenoid content as well as the net photosynthetic rate (PN) during subsequent days of transfer to ex vitro condition. Moreover, acclimatization had a significant effect on biomass production and the synthesis of 2-hydroxy-4-methoxy benzaldehyde (2HMB). Maximum fresh weight (3.78 gm/plant), dry weight (0.39 gm/plant) of roots and 2HMB content (15.94 µg/ml of extract) were noticed after 8 weeks of acclimatization.
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