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Vitellogenin (Vtg) has proven to be a sensitive and simple biomarker in determining sex, sexual maturity, and xenoestrogenic effects in fish. Thus, our investigation has been focused on identification, partial characterization, and quantification of grey mullet (Mugil cephalus) Vtg through the use of a variety of biochemical and immunological analytical techniques. Mullet is considered both a promising aquaculture candidate and an important species for improving sediment quality in polyculture systems. In the first part of this work, grey mullet Vtg was purified from plasma of 17β-estradiol (E2)-induced male fish by a one-step chromatographic protocol, and partially characterized. Specific polyclonal antibodies were then raised against the mullet Vtg, and both an indirect ELISA and an optical immunosensor were set up and validated to quantify plasma Vtg. The indirect ELISA and the optical immunosensor assay developed showed linear measuring in the range 56.8–1047.1 ng mL−1 and 70–739 ng mL−1 Vtg concentrations in standard solutions, respectively. The results obtained suggest that the indirect ELISA allows Vtg detection over a wide dynamic range, thus resulting more suitable for rapid and sensitive sample screening. Therefore, we suggest that the direct immunosensor is a promising tool which needs more investigation to improve the sensitivity.  相似文献   
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Enzyme-derived products obtained from thio-functionalised glucosinolates showed high fungitoxicity, a wide activity spectrum and special physicochemical properties, which suggest their potential as alternatives to commercial fumigants for controlling several soil-borne pathogens. © 1999 Society of Chemical Industry  相似文献   
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The economically most damaging disease to winter rye is brown rust (Puccinia recondita f.sp.secalis Rob.ex Desm.). There are fungicides of different drug groups in order to fight brown rust in agriculture. Usually mixtures of different active ingredients with different modes of action can be used for the treatment of fungal pathogens. In experiments single agents like pyrazole-carboxamides, azoles and strobilurines were compared to drug combination products like azole strobilurin, azole-carboxamide, or azole carboxamide-strobilurin mixture and their fungicide performance was determined. The active ingredients Epoxiconazole, Pyraclostrobin, and Fluxapyroxad were tested. In eight trials from 2012 to 2013 Fluxapyroxad reached the highest levels of efficiency for P. recondita. Pyraclostrobin or the combination of Pyraclostrobin and Epoxiconazole showed higher efficiencies than Epoxiconazole or the combination of Epoxiconazole and Metconazole in all trials. The thousand seed weight and income from the harvest reflect the efficiency against P. recondita. Both azole strobilurin mixtures as well as the azole carboxamide mixtures are suitable for the control of leaf rust in agriculture. In order to minimize the risk of resistance to strobilurin and azole carboxamide mixtures should be used alternately.  相似文献   
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The status of the Potato virus Y (PVY) in Swiss seed potato production was investigated in the years 2003 and 2008 by analysing 385 leaf samples of field-grown, suspicious potato plants collected in four representative seed control fields. Serological investigations by ELISA showed that in c. 84% of the PVY-positive samples in both years, viruses belonging to the PVYN group were found. All 124 serologically positive PVY samples collected in 2003 and a selection of 81 isolates of 2008 were further typified by molecular tests and by biological assays on tobacco and potato plants. These tests largely confirmed the predominance of the PVYN group and, within this group, the prevalence of recombinant PVYNTN, with 81.4% and 70.4% in 2003 and 2008, respectively. The percentage of PVYN-Wilga (PVYN-Wi) increased from c. 6% to 17% between the two years. PVYO was detected only in 10.5% and 4.9% of all molecularly analysed samples in 2003 and 2008, respectively. The persistent predominance of recombinant PVYNTN in Swiss seed potatoes indicates that this strain group is now widespread, representing a considerable threat to Swiss seed potato production.  相似文献   
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Resistance to the fungicide boscalid in laboratory mutants of Botryotinia fuckeliana (Botrytis cinerea) was investigated. The baseline sensitivity to boscalid was evaluated in terms of colony growth (EC50 = 0.3–3 μg ml−1; MIC = 10–30 μg ml−1) and conidial germination (EC50 = 0.03–0.1 μg ml−1; MIC = 1–3 μg ml−1) tests. Mutants were selected in vitro from wild-type strains of the fungus on a fungicide-amended medium containing acetate as a carbon source. Mutants showed two different levels of resistance to boscalid, distinguishable through the conidial germination tests: low (EC50 ∼ 0.3 μg ml−1, ranging from 0.03 to 1 μg ml−1; MIC > 100 μg ml−1) and high (EC50 > 100 μg ml−1) resistance. Analysis of meiotic progeny from crosses between resistant mutants and sensitive reference strains showed that resistant phenotypes were due to mutations in single major gene(s) inherited in a Mendelian fashion, and linked with both the Daf1 and Mbc1 genes, responsible for resistance to dicarboximide and benzimidazole fungicides, respectively. Gene sequence analysis of the four sub-units of the boscalid-target protein, the succinate dehydrogenase enzyme, revealed that single or double point mutations in the highly conserved regions of the iron-sulphur protein (Ip) gene were associated with resistance. Mutations resulted in proline to leucine or phenylalanine replacements at position 225 (P225L or P225F) in high resistant mutants, and in a histidine to tyrosine replacement at position 272 (H272Y) in low resistant mutants. Sequences of the flavoprotein and the two transmembrane sub-units of succinate dehydrogenase were never affected.  相似文献   
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The plastome sequence of the European cultivated potato, Solanum tuberosum subsp. tuberosum (tbr, GenBank accession no. DQ386163), was compared with that of S. bulbocastanum, a wild potato relative (blb, GenBank accession no. DQ347958), in order to characterize the degree and type of variability in different genomic regions, and develop molecular markers relevant to genetics, breeding and biotechnology of potato. One hundred forty-two and 251 PICs (Potentially Informative Characters) were found in coding and non-coding sequences (NCSs), respectively. Further, while variation in coding regions was almost exclusively due to nucleotide substitutions, 25% of PICs in NCSs of tbr and blb were due to indels, most of them mononucleotide or longer tandem repeats (micro and minisatellites). Four intergenic regions were selected for further analyses in other 16 tuber-bearing Solanum species. The rps16-trnQ UUG gene spacer was found to be the most variable, forty-six PICs in this region distinguishing 18 haplotypes. Analysis of haplotype relationships, based on variability in the four intergenic regions, confirmed that the most primitive species from Central America were the most distant to S. tuberosum. Finally, polymorphic sites in the same regions were used to develop a set of CAPS (Cleaved Amplified Polymorphic Sequences) markers for species/cytoplasm identification in Solanum spp.  相似文献   
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Résumé On présente des données sur la persistence du DDT sur tomates, poivrons, et aubergines en plein champ, et sur tomates en serre, à la suite de l'application des traitements par concentrés émulsifiables. Dans le cas des tomates on a constaté que le dépôt résiduel est audessous de 1 ppm apres un intervalle de 11 jours depuis l'application du traitement en champ. En serre, et pour la même quantité de substance toxique, la persistence se maintient jusqu'à 36 jours.Le dépôt initial sur aubergines est plus élevé que dans le cas des tomates, atteignant jusqu'à 1 ppm. après environ 22 à 29 jours. Chez les poivrons, le résidu initial est très grand par rapport aux deux premières légumes et atteint 19 ppm. 22 Jours après le traitement celui-ci varie entre 0,8–1,3 ppm.Ensuite, on a étudié la dynamique de la répartition dans le temps de la substance toxique par unité de surface. Les résultats obtenus démontrent l'uniformité des traitements; la diminution de la quantité de substance toxique dans le temps est due autant au facteur croissance qu'aux conditions de climat.
Summary The paper deals with data on the persistence of DDT on tomatoes, sweet peppers and eggplants in the field, and on tomatoes in the greenhouse, following the application of emulsions. It is shown that in tomatoes, residual deposits are below 1 ppm 11 days after treatments in the field. In the greenhouse, the persistence is long-lasting, attaining up to 36 days when the same amount of toxicant is applied.In eggplants, the initial deposit is higher than in tomatoes attaining about 1 ppm after 22–29 days. In sweet peppers, the initial amount of residue is very large as compared to the first two vegetables and attains 19 ppm; 22 days after the treatement it ranges between 0.8–1.3 ppm.Besides, the dynamics of toxicant distribution with time, per area unit was studied. The data obtained demonstrate the uniformity of the treatments, and that the diminution of the amount of toxicant with time is due to both the growth factor and the climate conditions.

Zusammenfassung In diesem Beitrag werden Daten betreffs der Karenzzeit der DDT-Rückstände auf Tomaten, Paprika und Eierfrüchten nach Behandlung des Feldbestandes und auf Tomaten, die im Treibhaus mit DDT-Emulsionen behandelt wurden, wiedergegeben. Aus unseren Untersuchungen geht hervor, daß der Rückstandswert auf Tomaten 11 Tage nach der Behandlung des Feldbestandes weniger als 1 ppm beträgt. Im Treibhaus hingegen erstreckt sich die Karenzzeit (Verweildauer) bis auf 36 Tage unter Anwendung derselben Wirkstoffmenge.Auf den Eierfrüchten ist der anfängliche Rückstandswert größer als auf den Tomaten und erreicht nach ungefähr 22–29 Tagen Werte unter 1 ppm. Im Falle der Paprikaschoten sind die Rückstandswerte anfangs sehr hoch im Gegensatz zu den vorher genannten Gemüsesorten und zwar erreichen sie 19 ppm. Nach 22 Tagen verzeichnen wir hier Werte von 0,8–1,3 ppm.Anschließend verfolgten wir die Dynamik der Wirkstoffverbreitung im Verhältnis der Zeit zur Oberflächeneinheit.Die erzielten Ergebnisse deuten sowohl auf eine uniform durchgeführte Behandlungsweise hin als auch auf die Tatsache, daß der zeitliche Rückgang der Rückstandsmenge von Wachstum und Klimabedingungen abhängig ist.


avec 4 figs.  相似文献   
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