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Na podstawie piśmiennictwa omówiono zagadnienia związane z właściwościami fizykochemicznymi i toksykologicznymi wielopierścieniowych węglowodorów aromatycznych (WWA). Szczególną uwagę zwrócono na procesy prowadzące do powstawania WWA, dystrybucję w środowisku, przemiany metaboliczne oraz potencjalne efekty szkodliwe wynikające z oddziaływania reaktywnych metabolitów z makrocząsteczkami komórkowymi.
The aim of investigation was to work out the analytical method of determination of mycotoxins such as: deoxynivalenol, nivalenol and zearlenon in maize grain samples. The analytical procedure consisted of three elementary processes: extraction of analyzed substances from matrix, cleaning of extract using SPE (Solid Phase Extraction) column with C18 active solid and final determination using high performance liquid chromatography with UV detection. The detection limit (LOD) of all tested mycotoxins was 0.002 mg/kg. The range of fortified recoveries of the method was 92–95%.
Reduced tillage systems in cereals may lead both to increasing weed infestation and a strong weed competition for living space and nutrients in the soil. As a consequence, this may favour the development of pathogenic fungi such as Fusarium spp. and generate a second contamination of grain with the fungies toxic metabolites. The aim of performed research was to determine the effect of weed infestation level in ploughless crop on the occurrence of diseases caused by Fusarium spp. on two winter rye cultivars, as well as laboratory analyses for mycotoxin detection in grain: deoxynivalenol and nivaleniol. As the result of poar efficacy of the herbicide Glean 75 WG (applied in the autumm) in controlling the weed species Apera spica-venti and Centaurea cyanus, and the infection winter rye grain cv. Dańkowskie Złote by Fusarium spp. an increased level of deoxynivalenol (0.08) was detected as compared both to the control object and herbicide protected object with Atlantis 040 WG + Actirob 842 EC.
Observed in last few years changes in climate conditions, especially changes in rainfalls, caused a difference in residues level determined in surface and groundwater. Intensive rainfalls caused an increase of herbicides leaching into surface and groundwater, but determined residues did not increase because the large quantity of water from the rainfalls had an influence on dispersion and dilution of residues in water.
Susceptibility of newly emerged seedlings of Norway spruce [Picea abies (L.) H. Karst.] to selected herbicides was examined under greenhouse conditions. The following active substances were investigated: propaquizafop (50 g/ha), mesotrione (100 g/ha), nicosulfuron (40 g/ha), pendimethalin (990 g/ha), fluroxypyr 125 (g/ha), clopyralid (90 g/ha), iodosulfuron-methyl-sodium (7.5 g/ha), MCPA (562.5 g/ha), clopyralid (100 g/ha) + fluroxypyr (150 g/ha) + triclopyr (200 g/ha), bentazone (1440 g/ha). Only after the application of propaquizafop no damages were observed. A low level of phytotoxicity (needle growth was slightly inhibited) occurred after pendimethalin and clopyralid application. The other herbicides caused major damages of seedlings. Following the visual assessment, the plants were cut and fresh shoot biomass was determined. Only propaquizafop did not affect biomass production, while the other herbicides significantly reduced the fresh biomass of seedlings.
The influence of different concentrations of Goltix 700 SC (a.s. metamitron) on Lemna minor L. is described in this article. The research was conducted under controlled environment conditions (climatic chamber) in Petri dishes. Metamitron at 70 mg/dm3 reduced fresh weight by 91% (dry weight 98%) in comparison with control, but when it was used at 0.7 mg/dm3, fresh weight of L. minor was reduced only by 10% (dry weight 37%). The observation showed that metamitron at 70, 35 and 7 mg/dm3 caused strong injuries, as the plant bleaching and roots reduction.
This paper presents the results of studies on the content of polychlorinated biphenyls (PCB's) in the fat of wild-boars shot in 10 selected areas of north-eastern Poland. All examined fat samples contained polychlorinated biphenyls. The mean level of PCB's in fat samples collected from wild-boars was 5.1 µg/kg. The highest mean levels of PCB's were noted in wild-boars from the Supraśl and Miłomłyn area. The presented data reveal that the levels of polychlorinated biphenyls were much lower than tolerated values for nutritive products, and at present there are no hygienic and toxicologic reservations. These studies illustrate the exposure of selected animal species and indirectly humans to these xenobiotics in north-eastern Poland.
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