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B. Wrzesińska A. Czerwoniec P. Wieczorek P. Węgorek J. Zamojska A. Obrępalska‐Stęplowska 《Insect molecular biology》2014,23(5):682-693
The pollen beetle (Meligethes aeneus F.) is the most devastating pest of oilseed rape (Brassica napus) and is controlled by pyrethroid insecticides. However, resistance to pyrethroids in Europe is becoming widespread and predominant. Pyrethroids target the voltage‐sensitive sodium channel (VSSC), and mutations in VSSC may be responsible for pyrethroid insensitivity. Here, we analysed individual beetles that were resistant to esfenvalerate, a pyrethroid, from 14 populations that were collected from oilseed rape fields in Poland. We screened the VSSC domains that were presumed to directly interact with pyrethroids. We identified 18 heterozygous nucleic acid substitutions, amongst which six caused an amino acid change: N912S, G926S, I936V, R957G, F1538L and E1553G. Our analysis of the three‐dimensional structure of these domains in VSSC revealed that some of these changes may slightly influence the protein structure and hence the docking efficiency of esfenvalerate. Therefore, these mutations may impact the susceptibility of the sodium channel to the action of this insecticide. 相似文献
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Wind-borne insects mediate directional pollen transfer between desert fig trees 160 kilometers apart
Sophia Ahmed Stephen G. Compton Roger K. Butlin Philip M. Gilmartin 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(48):20342-20347
The question of how far pollen can move between plants has implications for topics as diverse as habitat fragmentation, conservation management, and the containment of genetically modified crops. The monoecious African fig tree Ficus sycomorus L. relies on the small, short-lived, night-flying, host-specific fig wasp Ceratosolen arabicus Mayr for pollination. We used microsatellite markers to characterize a geographically isolated riparian population of F. sycomorus growing along the Ugab River in the Namib Desert, Namibia, together with paternity analysis of seedlings from known mothers, to map pollen movement within this population. In this way we tracked insect movements between individually recognizable trees by means of their pollen cargo and documented the movement of C. arabicus between known trees separated by more than 160 km, with a mean distance for confirmed successful pollination events of 88.6 km. The predominant observed movement of pollinators was in a westerly direction, toward the sea, reflecting seasonal nighttime wind direction and the wind-borne dispersal of fig wasps. Our results suggest the existence of an extensive panmictic population of trees that are well suited to overcome the effects of geographical isolation. 相似文献
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Jarmila Čelakovská Květuše Ettlerová Karel Ettler Josef Bukač 《Food and Agricultural Immunology》2015,26(5):671-681
The objective of this study is to evaluate if there is a difference in the occurrence of asthma bronchiale, rhinitis, pollen allergy, food allergy and sensitization to basic food allergens, onset of atopic dermatitis (AD), family history about atopy, and duration of eczematic lesions in AD patients with the level of total immunoglobulin E (IgE) under or above 200 IU/ml. Complete allergological and dermatological examination was performed and the statistical evaluation of the relations among the patients with the level of IgE under 200 IU/ml and above 200 IU/ml was performed. Out of 277 patients suffering from AD, we included 87 men and 190 women; the average age was 25.9 years. From 277 patients, 92 patients (33%) have IgE under 200 IU/ml; in these patients, the occurrence of tested parameters is significantly lower in comparison to patients with IgE above 200 IU/ml. 相似文献
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