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In 1973–2011 in Poznań, aphid catches were carried out using Johnson’s suction trap. Since then the suction trap located at the Institute of Plant Protection – National Research Institute in Poznań has continuously recorded the daily and seasonal dynamics of aphid flights. The collected results has been used to establish one of the largest databases of this type in Europe. The data also allow tracking changes in aphid biodiversity under the changing climatic conditions. Three aphid species of Diuraphis spp. were identified: D. muehlei (Börner, 1950) – in 1974, D. bromicola (Hille Ris Lambers, 1959) – in 1988, D. noxia (Kurdjumov, 1913) – in 2003 as a result of systematic and long-term aphid collections. The occurrence of D. noxia presents a particular risk to cereal crops in Poland. This expansive aphid species that originates from Asia and the Mediterranean is a vector of Barley yellow dwarf viruses (BYDV), and has become one of the most important pest of wheat and barley in the world. Changes in climatic conditions that have been observed in recent years in Poland such as hot summer, long and warm autumn, mild winter seem to be optimal for occurrence and development of aphid species from warmer parts of Europe.
Results of two-year studies on the aphids number in different uncultivated habitats (field boundaries, roadsides, field shrubs and forest margins) are presented. The analysis of data permitted to distinguish two basic types of change in the aphids number in a vegetation season.
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Aphid infestation of decorative perennials

75%
The many years’ study on species composition and harmfulness of aphids infesting perennials in the decorative plant collection Agricultural University in Poznań permited to ascertain occurrence of 23 aphid species on 66 species of decoratice perennials, representing 20 botanical families. The species that occurred in all the four study seasons in 2000, 2002, 2003 and 2005 included: Aphis fabae Scop., Brachycaudus cardui (L.) and Aphis sedi Kalt.. Very often Aphis newtoni Theob., Acyrthosiphon malvae (Mosl.), Brachycaudus helichrysi Kalt. and Longicaudus trirhodus (Walk.) were found. Spring and early summer was the period of numerous occurrence of aphids on decorative perennials. The high degree of plant infestation was resulted in decreasing the plant’ decorative value. The aphid infestation may be especially dangerous for numerous cultivars of Dahlia x cultorum, Eryngium planum, Echinops ritro, Leucanthemum maximum, Papaver orientale, Sedum aizoon, Iris sibirica, Yucca filamentosa, Achillea ptarnica, Dicentra eximia, Doronicum orientale i Geum coccineum.
The studies were carried out on the maize crops grown in monoculture in 2004-2005 on two experimental fields at Łosiów and Wronów in Opole region, Poland. From the aphid mummies collected at both sites secondary parasitoids of the families Pteromalidae, Cynipidae, Megaspilidae, and Encyrtidae were reared. In spring and early summer of 2004, the most abundant were the species of Pteromalidae, with the eudominating species Asaphes suspensus NEES. At the same time of the next year the dominant species were Dendrocerus carpenteri (CURTIS) (Megaspilidae) and Phaenoglyphis villosa (HARTIG) (Charipidae: Alloxistinae). In autumn, the secondary parasitoids occurred only in the second year of the study, 2005. The dominant species at both sites was Phaenoglyphis xanthochroa (FÖRSTER) (Charipidae: Alloxistinae). In the literature available so far there are no data on secondary parasitoids incidence on maize crop in autumn.
The cowpea aphid, Aphis craccivora management relies mainly on chemical control. As a result extensive and repeated treatment of insecticides has led to the development of aphid resistance to commonly used insecticides. To investigate chlorpyrifos-methyl resistance in A. craccivora, a field strain was selected for 24-generations to achieve a resistance factor of 82.3 fold compared with a susceptible strain. In the resistant strain, malathion and lambda-cyhalothrin exhibited obvious cross-resistance; while fenvalerate and dinotefuran showed moderate cross-resistance. In contrast, slight or no cross-resistance was obtained with the other tested insecticides. To investigate metabolic resistance mechanisms, integration of biochemical and synergism assays was conducted. Results showed the key role of esterase (EST) and mixed function oxidases (MFO); however, glutathione-s-transferase (GST) contributed less to resistance. Cross-resistance studies showed the need for rotation with non-cross resistant insecticides as a resistance management tactic.
Epicuticular components from the surface of flag leaves and ears of the triticale cultivars were identified by combined gas chromatography/mass spectrometry. After separating dichloromethane extracts of flag leaves and ears, the major chemicals of the LAD 898 cultivar were 14,16- hentriacontanedione (39.01 V40.21%) and lauric acid 2-(hexadecyloxy)-3-(octadecyloxy) propyl ester (15.22%-23.02%), while waxes of flag leaves and ears of MSx366 contained a high percentage of octacosane and triacontane. The results presented here suggest that 14,16-hentriacontanedione and lauric acid 2-(hexadecyloxy)-3-(octadecyloxy) propyl ester might be responsible for resistance of waxy triticale to the grain aphid.
Studies on the population dynamics of aphids Cinara juniperi De Geer on the shrubs of Juniperus communis L. in the urban conditions of Lublin were conducted in the years 2002–2004 in two types of sites: a street one and a park one. The first individuals of this species were most frequently observed at the turn of April and May, while the maximum population was found in the first half of May. The course of the weather conditions affected the population dynamics of aphids. Those insects were observed in much bigger numbers on the shrubs growing in the street site. The preying of C. juniperi caused browning and drying out of the needles and inhibition of the stem growth, which had an influence on lower decorative character of the examined plants.
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