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Observations on the aphid number were carried out in the years 2001–2003, simultaneously in four different sites. In each of these three shrubs were marked: of park rose ‘Grandhotel’, rugosa rose, multiflorous rose and five shrubs of border roses of various cultivars. The purpose of these study was to conduct a quantitative analysis of the aphid fauna colonizing roses growing in various types of city green areas. As a result of studies conducted the occurrence of 10 aphid species was found out on the analyzed shrubs. No significant differences were observed in the species composition of aphids colonizing roses growing in various types of city green areas. The studies showed significant differences in the aphid number between the analyzed sites. The road and street sites on the one hand and the road and housing estate ones on the other were most similar regarding the number of aphids.
Extensive studies have been carried out to identify plant phenolics with insecticidal properties towards insects. The subject of the study were comparison of control and infested by Acyrthosiphon pisum (Harris) vegetative parts of pea plants. In the pea plants six flavonol aglycones were identified: quercetin, kaempferol+RCO-, kaempferol, tricin, apigenin+RCO-, and apigenin. In infested plants relatively high concentration of total phenols, o-dihydroxyphenols and total flavonoids in comparison with control were observed. It suggests that phenolics have negative effect on insects and they are good for control of the insect pests.
Rapessed and mustard are important oilseed crops in India. The vulnerability of the crop to mustard aphid, Lipaphis erysimi Kaltenbach is the main bottleneck in successful cultivation of this crop. In order to use insecticides at a minimum level, effectiveness of different Integrated Pest Management (IPM) modules were tested under field conditions. The module (NSKE + Chrysoperla carnea) proved most effective in reducing the aphid population in terms of socio-economic and environmental values.
The effect of heavy metal ions (Cd, Cr³⁺, Cu², Ni, Pb²⁺ and Zn) on the growth and germination of conidia of the aphid pathogenic fungus Pandora neoaphidis was studied. The metal ions were added into the culture medium in three concentrations: A – concentration corresponding to the mean content of that metal in Polish soils, B – concentration 10-times higher and C – 100-times higher than the mean ones. The investigated heavy metal ions, except for Ni, added to the media at the concentrations corresponding to the mean content of these metals in Polish soils, did not affect the growth of aphid-pathogenic fungus Pandora neoaphidis. Ni, Cu, Zn and Cr, added to the media at a concentration 100-times higher than in Polish soils, prevented the growth of the pathogen. All the tested metal ions, except for Cu, added to the media at the mean soil concentration, did not affect conidial germination of the fungus. The conidia of P. neoaphidis were unable to germinate in the presence of the Cr, Cu, Pb and Zn ions in the medium at a concentration that was 100-times higher than the mean one. Cu and Zn caused a significant reduction of conidial germination even at a concentration that was 10-times higher than the mean content of these metals in Polish soils. This work suggest that strong pollution of soil by some heavy metals could be a restrictive factor of development and pathogenicty of entomophthoralean fungi in the environment.
Observations were conducted in the years 1999-2001 on the shrubs Pinus mugo Turra growing in the green areas of Lublin in two sites (street and park). The purpose of the studies was to establish the domination and frequency of aphids, their effect on the decorative character of shrubs and the occurrence of the aphidophagous arthropods in the aphid colonies inhabiting mountain pine. It was found out that Schizolachnus pineti F. was the dominating species in the street site (A), while Ci tiara pini L. dominated in the park site (B). The decorative character of shrubs was clearly lowered only by aphids S. pineti. Predatory arthropods occurred in aphid colonies inhabiting the shrubs P. mugo. Their population in both sites was low, that is why they probably had little influence on limiting the aphid population. Parasitic Hymenoptera of I and II degrees obtained from a culture of aphid mummies were more numerous in the street site.
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