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121.
Guénola Pérès Franck Vandenbulcke Muriel Guernion Mickaël Hedde Thierry Beguiristain Francis Douay Sabine Houot Denis Piron Antoine Richard Antonio Bispo Cécile Grand Laurence Galsomies Daniel Cluzeau 《Pedobiologia》2011
Considering the limited number of bioindicators available to assess soil quality, a national research programme was set up in France to develop such indicators (2006–2012), the “Bioindicator” programme. This programme tested 47 biological parameters (i.e. microorganisms, fauna, flora) including earthworms, in several sites differing in terms of land use, contamination type – PAHs or metals – and pollution levels. The present study proposes some study objectives for bioindicator approaches, based on the earthworm results from the programme. Therefore, different earthworm descriptors were tested at the community level (e.g. abundance, biomass, species and functional structures, and ecological traits) as well as the organism level (i.e. measuring the metallothionein coding gene expression level in earthworms). The present results, obtained from the programme's spring 2009 sampling campaign, discriminated among the different descriptors and showed that earthworm and endogeic abundance as well as the individual weight of endogeics seem to be good indicators in non-contaminated (cultivated) sites, while the ecological structure, namely the proportion of anecic vs. endogeic species, and the proportion of non-vulnerable species should be used as indicators of contaminated soils. Furthermore, the first results obtained for Lumbricus terrestris and L. rubellus rubellus are encouraging as they show that metallothionein expression increases in metal-contaminated soils. The relevance of these descriptors, which have to be considered in study objectives, requires the analysis of 2010 results. 相似文献
122.
As a result of the study carried out between 2007 and 2009 in the eastern part of the Black Sea Region of Turkey, 4 genera and 17 species were determined as new records for the Turkish aphid fauna. New recorded species are Aphis arbuti, Aphis cytisorum, Aphis kachkoulii, Cavariella digitata, Chaitophorus kapuri, Chaitophorus longisetosus, Cinara pinivora, Illinoia lambersi, Myzus beybienkoi, Neobetulaphis pusilla, Phyllaphis fagifoliae, Pseudessigella brachychaeta, Schizaphis rotundiventris, Symdobious oblongus, Thecabius lysimachiae, Thelaxes californica and Tinocallis takachihoensis. With these new records, the number of genera increased to 134 and the number of the species in the Turkish aphid fauna amounted to about 480. Since Turkey has a huge range of agricultural crops and a great diversity in its natural flora, research conducted on the Turkish aphid fauna has current and future indications for plant protection. 相似文献
123.
Ömür Baysal Francesco Mercati Hatice İkten Raziye Çetinkaya Yıldız Francesco Carimi Yeşim Aysan Jaime A. Teixeira da Silva 《Physiological and Molecular Plant Pathology》2011,75(3):113-119
There is no available data published related to the dissemination of bacterial canker caused by Clavibacter michiganensis subsp. michiganensis (Cmm) and its genetic diversity in Turkey. It is important to control new introduced inoculum sources by commercial seeds and seedlings. Pathogens were identified by morphological features and the identity was confirmed by PCR amplification using a specific primer PSA-4, PSA-R in addition to microbiological tests. ISSR markers showing high polymorphism ratios were selected and used to characterize Cmm strains. The collected strains were classified into different groups on the basis of ISSR-PCR fingerprints, which showed remarkable genetic specificity and diversity not previously identified in Cmm, suggesting that genetic differences are related to dissemination of the pathogen in the region. This is the first ever study carried out on the characterization of Cmm using ISSR. The selected ISSR primers to characterize Cmm can be used to determine genetic differences in further studies. 相似文献
124.
Marie-France Corio-Costet Marie-Cécile Dufour Jérémy Cigna Pierre Abadie Wei-Jen Chen 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(2):315-329
The effectiveness of Quinone outside Inhibitor (QoI) fungicides against grape downy mildew in European vineyards has significantly
decreased in the last decade. One nucleotide polymorphism, G143A in the cytochrome b gene of Plasmopara viticola, is involved in resistance to QoIs. Previous genetic examination on the mitochondrial genomes showed four major haplotypes
(IR, IS, IIR, IIS) coexisting in European vineyards. A resistant allele (G143A) was present in IR and IIR haplotypes. The
purpose of the present study was to estimate the diversity of the different mitochondrial haplotypes and their distribution
in QoI-resistant populations before evaluating the potential cost of the resistant mutation G143A in P. viticola population. From 2000 to 2004, the frequencies of resistant isolates ranged from 0% to 23.25% with an average of 4.64 % among
the populations examined. To evaluate the fitness of sensitive and resistant isolates, a comparison of different biological
parameters including latent period, spore production and infection frequency was performed, enabling a fitness index (FI) to be determined. Resistant isolates exhibited greater infection frequency than sensitive isolates, whereas no significant
difference was found in sporulation ability and latent period between sensitive and resistant isolates. To further investigate
competitiveness among isolates, an assay including two resistant isolates in different proportion with a sensitive isolate
was conducted on eight asexual growing cycles in the absence of a QoI fungicide. The competitiveness of resistant isolates
varied according to their fitness parameters, suggesting that there is no noticeable cost of QoI resistance in controlled
conditions in Plasmopara viticola. 相似文献
125.
Engel E Nicklaus S Garem A Septier C Salles C Le Quéré JL 《Journal of agricultural and food chemistry》2000,48(9):4252-4259
The aim of this study was to evaluate the impact of the components of a goat cheese water-soluble extract (WSE) on its flavor by both physicochemical and sensory techniques with special emphasis on taste. After characterization of the organoleptic properties of the cheese, the WSE was extracted with pure water and submitted to successive tangential ultrafiltrations and nanofiltration. The physicochemical assessment of these fractions led to the constitution of a model mixture (MWSE) compared by sensory evaluation to the crude WSE, using a panel of 16 trained members. The results of both sensory profile and triangular tests indicate no significant difference, therefore proving that the reconstitution of the WSE was correct, thereby showing the sensory neutrality of lipids and peptides smaller than 500 Da, which had not been included in the MWSE. Moreover, the cheese gustatory characteristics are comparable to those of the WSE despite weaker levels of sharpness and astringency in the extract, the respective origins of which are discussed. 相似文献
126.
Schrooyen PM Dijkstra PJ Oberthür RC Bantjes A Feijen J 《Journal of agricultural and food chemistry》2000,48(9):4326-4334
Feather keratins were extracted from chicken feathers with an aqueous solution of urea and 2-mercaptoethanol. The keratin solution obtained was dialyzed to remove the reagents. Upon dialysis, extensive protein aggregation occurred. To obtain stable solutions or dispersions in water, cysteine residues were modified prior to dialysis with iodoacetamide, iodoacetic acid, or bromosuccinic acid, thereby blocking free thiol groups and introducing hydrophilic groups. For the development of biodegradable materials with good mechanical properties from these biopolymers, disulfide bonds between the keratin molecules are needed. Therefore, cysteine residues were only partially modified by using different reagent/cysteine molar ratios. The reaction rate constants of iodoacetate with glutathione and 2-mercaptoethanol were successfully used to predict the degree of modification of keratin cysteine. It was shown that, for carboxymethylated keratin, fewer aggregates were formed for higher degrees of cysteine modification, while more protein was present as oligomers. Aggregates and oligomers were stabilized through intermolecular disulfide bonds. 相似文献
127.
Determination of key odorant compounds in freshly distilled cognac using GC-O, GC-MS, and sensory evaluation 总被引:6,自引:0,他引:6
Ferrari G Lablanquie O Cantagrel R Ledauphin J Payot T Fournier N Guichard E 《Journal of agricultural and food chemistry》2004,52(18):5670-5676
This aim of this work was to identify the odorant compounds responsible for the typical sensory descriptors attributed to freshly distilled Cognac spirits, not matured in barrels. Panelists were first selected and trained for gas chromatography-olfactometry. Among the 150 volatile compounds identified by gas chromatography-mass spectrometry analysis, only 34 are mainly responsible for the odors detected in the spirits. The "butter" descriptor is explained by the presence of diacetyl, the "hay" descriptor by nerolidol, the "grass" descriptor mainly by Z-3-hexen-1-ol, but also by other compounds, the "pear" and "banana" descriptors by 2- and 3-methylbutyl acetates, the "rose" descriptor by 2-phenylethyl acetate, and the "lime tree" descriptor by linalool. This study demonstrated that many odorant molecules are already present in freshly distilled Cognac, thereby giving the spirit its specific aroma. 相似文献
128.
Csomós E Héberger K Simon-Sarkadi L 《Journal of agricultural and food chemistry》2002,50(13):3768-3774
Biogenic amines, polyphenols, and resveratrol were analyzed quantitatively in 25 different Hungarian wines from the same wine-making region, harvest of 1998. Polyphenols were determined according to a spectrophotometric method, whereas other substrates were analyzed using overpressured-layer chromatography (OPLC). Principal component analyses (PCA) were performed on data matrices consisting of substrates (columns) and different sorts of wines (rows) from the region of Pécs (southern Hungary). It was found that four (unrotated) principal components account for >80% of the total variance in the data. The plots of component loadings showed significant groupings for concentrations of biogenic amines (and polyphenols). Similarly, the component scores grouped according to the different sorts of wines. The loading plots reveal that there is no need to measure all of the variables to achieve the same characterization. It is enough to measure one variable per group. Naturally, this conclusion is valid only within the limits of the present study; wines from other regions may behave differently. 相似文献
129.
Regina Célia Faria Simão Canesin Salatiér Buzetti Juliana Aparecida de Souza 《Journal of plant nutrition》2015,38(4):639-646
Boron (B) is transported mainly in the xylem, but by using isotopic tracers it was possible to verify that B has significant mobility in the phloem of polyols-producing species. Thus, the objective of this study was to evaluate the mobility of 10B applied to cashew plants. The experiment was conducted from 05/10 to 07/10/2010 in a greenhouse of University of São Paulo State-UNESP, Ilha Solteira Campus, State of São Paulo, Brazil. 0.5 mg of B L?1 of soil was used in the substrate. A solution of 255 mg of B L?1 was used in recently mature and fully developed leaves. The total content of B and and percentage of boron in the plant derived from fertilizer (Bppf%) were evaluated in the old and new leaves stemming at 30 and 60 days after the application of 10B. As evidenced, B applied to leaves had restricted mobility in cashew tree. However, B applied in the substrate was absorbed and translocated to young leaves. 相似文献
130.
The objective of this study was to compare the concentrations of 17 beta-estradiol, progesterone, cAMP and cGMP in the follicular fluid of the largest cow follicle from the follicular phase of physiological sexual cycle and of follicles after synchronization of fut by cloprostenol (PGF2 alpha) and superovulation treatment with serum gonadotrophin (PMSG), in dependence on steroidal dominance of follicles. 2 x 25 cows, Slovak Pied x Lowland Black-Pied crossbreds with active corpus luteum, were subjected to superovulation treatment on the basis of rectal examination. Rut synchronization was achieved by cloprostenol of Czechoslovak provenience (Oestrophan Spofa), administered at the amount of 500 micrograms per dose. Serum gonadotrophin (Bioveta Concern, Ivanovice na Hané) at the amount of 2500 I. U. was administered forty-eight hours before the second dose of closprostenol. The animals were killed in slaughterhouses 48 hours later, or 72 hours later, since administration of the second dose of cloprostenol. The phase of the sexual cycle of control animals was determined by the method after Ireland et al. (1980) on the basis of morphological appearance of corpus luteum, presence of large preovulation follicle and by means of average concentrations of progesterone in blood serum. Aspirated follicular fluid was centrifuged using a cooling centrifuge at 3000 G. After separation, the supernatant was stored in a freezer at -18 degrees C until further treatment. 17 beta-estradiol and progesterone in the follicular fluid were determined by means of kits under the brand-names RIA-test-ESTRA (SI-125-9), or RIA-test-Prog (SI-125-6). Concentrations of cyclic nucleotides were determined by the RIA kits from the Institute vor Radioisotope Research, Production and Use (Prague), cAMP by 125J RIA kit (RIO12) and cGMP by 125J RIA (RIO42).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献