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Cereal straw is used as the most common substrate for Pleurotus ostreatus (Fr.) Kumm. cultivation. However other easily available and cheep materials are being sought. Textile industry wastes, among others, seem to be suitable materials. The effect of the kind of substrate on the mycelium growth, enzymatic activity and yield of Pleurotus ostreatus (Fr.) Kumm. was investigated. The subjects of the studies were the ‘K22’ and ‘P80’ strains of P. ostreatus and four substrates: i.e. alder sawdust, rye straw, hemp and flax shive. The type of substrate was found to affect the examined P. ostreatus parameters. The examined strains responded similarly to the applied substrate type. The best mycelium growth was obtained on the substrate from flax shive. The activity of the laccase enzyme turned out to be the highest on the hemp shive and the same substrate also yielded the highest crop of carpophores. The obtained results corroborated high usefulness of hemp and flax shive for the cultivation of P. ostreatus.
We measured cadmium and lead concentrations in two littoral plants (Phragmites australis Cav. Trin ex. Steudel and Typha angustifolia L.) collected in June and September 2007 from five selected lakes in the Poznan city area, and also in sediment and water samples from the same places. We determined the metal concentrations in rhizomes and leaves, and in sediment and water from the littoral and near the bank zone. Only low levels of the heavy metals were found. Pb and Cd concentrations were higher in water collected from the bank zone than from the littoral zone. Pb and Cd accumulation was noted in sediments. Heavy metal levels were higher in rhizomes than in stems and leaves. The studied aquatic macrophytes may be bioaccumulators and bioindicators of Pb and Cd in freshwater in natural conditions, even when concentrations are low.
One-year-old cuttings of basket willow (Salix purpurea × viminalis) were cultivated hydroponically under increasing Cu concentrations (0, 1, 2 and 3 mM) and at four Ca/Mg ratios (4:1, 1:10, 20:1 and 1:¼). After 14 days, rhizosphere and leaf samples were analysed. Salix plants were able to release relatively high amounts of low molecular weight organic acids (LMWOAs) in a short period of time. The total amount of LMWOAs increased with increasing Cu concentrations. Oxalic and acetic acids were dominant, and act as complexing agents for Cu ions, and therefore, organic exudates should be taken into account in phytoextraction of polluted areas. The Ca/Mg ratio of the medium significantly influenced not only concentration, but also the composition of LMWOAs. Phenolics content in leaves increased with the excess of Ca and Mg and with Cu level in the medium for all Ca/Mg ratios. The accumulation of glucose, fructose and sucrose in leaves was observed for deficiency and excess of Ca and/or Mg and Cu treatment at all Ca/Mg ratios. Excess calcium (Ca/Mg = 20:1) led to strong induction of salicylic acid biosynthesis, probably resulting from enhanced oxidative stress.
The cultivation of fungi is associated with the large production of spent mushroom compost (SCM), that have great ability to degrade lignin-like pollutants. The use of SMC to clean up contaminated soil is a promising alternative to other more expensive methods. A 12-week experiment with spent mushroom composts from Agaricus bisporus (champignon) and Lentinula edodes (shiitake) was carried out to compare their ability to degrade PAHs. The degradation of PAHs by Agaricus bisporus was in the following order: anthracene, pyrene, fluoranthene, and phenanthrene (87, 85, 83 and 79% of the control). The strongest degradation by Lentinula edodes was confirmed for anthracene (86% of the control), then for phenanthrene, fluoranthene and pyrene (78, 70 and 63% of the control, respectively). After a brief reduction of naphthalene content, a rapid increase was noted for both Lentinula edodes and Agaricus bisporus (170 and 149% of the control, respectively, at the end of the experiment).
This work reports a part of hydroponic experiment results concerning changes in Salix viminalis L. cv. ‘Cannabina’ morphology and physiology under stress conditions with different copper concentration levels and verifies our earlier results about the role of different Ca/Mg ratios in trace elements’ accumulation efficiency. In this part, we present the copper accumulation and changes in willow biomass. Concentration of copper in roots, rods, shoots and leaves was analyzed with flame atomic absorption spectrometry. Selected indices characterizing copper accumulation and plant biomass structure were calculated to estimate the potential of willow to remove metal from polluted solution. Our results indicate a general increase of copper accumulation by selected willow organs with increase of copper concentration in modified Knop’s medium. Moreover, significant differences in copper phytoextraction between plants under different Ca/Mg ratios were affirmed (1:10[4:1[20:1[1:1/4).
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