As trophic organisms, nematodes play an essential role in the soil environment: they mineralize nutrients into plant-available forms, are a food source for other soil organisms, and feed on ...pathogenic organisms and plant pests, therefore regulating populations of soil microorganisms. The plant-parasitic nematodes are important pests of crops. Nanoparticles (NP) are increasingly used in agriculture and other production sectors. They are present in the soil, not necessarily in trace amounts, and can affect various soil organisms, including nematodes. In this article, the effects of silver (Ag), gold (Au), and platinum (Pt) nanoparticles on the mortality and reproduction activity of selected nematode species from two trophic groups: entomopathogenic nematodes (EPN) (
and
) and plant parasitic nematodes (PPN) (
,
,
) were studied under laboratory conditions. All nanoparticles decreased the nematode population to an extent depending on the nematode species, nanoparticle type, and exposure time. AgNP had the greatest nematicidal effect, except for AuNP, which reduced the population of
the most. The greatest sensitivity to AgNP was observed in
(100% mortality),
(90% mortality), and 37 to 13% mortality in other species. Effect of AuNP and PtNP on entomopathogenic nematodes was comparable to the control, not treated with nanoparticles. AuNP and PtNP similarly influenced nematode mortality. However, the effect of nanoparticles on new generations of entomopathogenic nematodes developing in host larvae
was inconclusive. All nanoparticles decreased the number of larvae of
and increased the number of
migrating outside the cadavers compared to the control.
COLONIZATION OF SELECTED ROSE VARIETIES BY PESTS AND PATHOGENS ADAMSKA, Iwona; DZIĘGIELEWSKA, Magdalena
Folia Pomeranae Universitatis Technologiae Stetinensis. Agricultura, Alimentaria, Piscaria et Zootechnica,
02/2017, Letnik:
330, Številka:
40
Journal Article
The measured rate of release of intercellular protein from yeast cells by ultrasonication was applied for evaluating the effects of sonication reactor geometry on cell disruption rate and for ...validation of the simulation method. Disintegration of two strains of Saccharomyces cerevisiae has been investigated experimentally using a batch sonication reactor equipped with a horn type sonicator and an ultrasonic processor operating at the ultrasound frequency of 20 kHz. The results have shown that the rate of release of protein is directly proportional to the frequency of the emitter surface and the square of the amplitude of oscillations and strongly depends on the sonication reactor geometry. The model based on the Helmholtz equation has been used to predict spatial distribution of acoustic pressure in the sonication reactor. Effects of suspension volume, horn tip position, vessel diameter and amplitude of ultrasound waves on the spatial distribution of pressure amplitude have been simulated. A strong correlation between the rate of protein release and the magnitude of acoustic pressure and its spatial distribution has been observed. This shows that modeling of acoustic pressure is useful for optimization of sonication reactor geometry.
Inspections of 521 small cellars inhabited by bats in Poland revealed the occurrence of 10 species: Myotis myotis, M. nattereri, M, brandtii, M. dasycneme, M. daubentonii, Eptesicus nilssonii, E. ...serotinus, Plecotus auritus, P. austriacus, and Barbastella barbastellus. P. auritus was the most frequent and abundant (410 sites, 54.5% records). M. daubentonii dominated in cellars of the NW and NE regions of the country, while P. austriacus was the most abundant in the SW region. Communities of bats hibernating in small cellars and large underground hibernacula differed significantly. Plecotus spp. clearly preferred small hibernation sites, while M. myotis large ones. Species richness and diversity were highest in NW and NE region where this type of roost had greatest importance to bat hibernation. Despite the fact that only single individuals occurred in 44.7% of cellars, these roosts, common and numerous in Poland, could be in total inhabited by tens of thousands of bats yearly.
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