An evolutionary ecology perspective to address forest pathology challenges of today and tomorrow     

Marie-Laure Desprez-Loustau  Jaime Aguayo  Cyril Dutech  Katherine J. Hayden  Claude Husson  Boris Jakushkin  Benoît Marçais  Dominique Piou  Cécile Robin  Corinne Vacher 《Annals of Forest Science》2016,73(1):45-67

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Optimal management of molds in stored corn     

Yigezu A. Yigezu  Corinne E. Alexander  Paul V. Preckel  D.E. Maier  C.P. Woloshuk  L.J. Mason  J. Lawrence  D.J. Moog 《Agricultural Systems》2008

Long term storage of corn is becoming more common due to the recent increase in the demand for corn by ethanol plants. Infection of maize kernels by toxigenic fungi remains a challenging storage problem despite decades of research. Experts in storage management propose the use of a combination of preventive and monitoring-based responsive strategies in response to mold risks. In this paper, a stochastic dynamic programming model is solved to determine the expected profitability and optimal combination, timing, and intensity of the proposed mold management strategies using farmers’ existing infrastructure. The results show that even with relatively high monitoring costs, maintaining high quality grain using a monitoring-based optimal mold management strategy costs less than the benefit it fetches. The current typical practice by Indiana farmers of aerating the grain until the end of December and doing nothing thereafter bears a high risk of economic losses if grain is to be stored until later during the summer. Generally, the optimal mold management strategy depends on monitoring the biophysical conditions of the grain and the time period under consideration. If the in-bin temperature is high and less than 5% of kernels are mold damaged, then aerating when the outside temperature is at least 3 °C less than the in-bin temperature and continuing to store the grain is the optimal strategy.  相似文献   

Variation in aggressiveness is detected among Puccinia triticina isolates of the same pathotype and clonal lineage in the adult plant stage     

Bénédicte Pariaud  Henriette Goyeau  Fabien Halkett  Corinne Robert  Christian Lannou 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(4):733-743

Puccinia triticina reproduces asexually in France and thus individual genotype is the unit of selection. A strong link has been observed between genotype identities (as assessed by microsatellite markers) and pathotypes (pools of individuals with the same combination of qualitative virulence factors). Here, we tested whether differences in quantitative traits of aggressiveness could be detected within those clonal lineages by comparing isolates of identical pathotype and microsatellite profile. Pairs of isolates belonging to different pathotypes were compared for their latent period, lesion size and spore production capacity on adult plants under greenhouse conditions, with a high number of replicates. Isolates of the same pathotype showed remarkably similar values for the measured traits, except in three situations: differences were obtained within two pathotypes for latent period and within one pathotype for sporulation capacity. One of these differences was tested again and confirmed. This indicates that the average aggressiveness level of a leaf rust pathotype may increase without any change in its virulence factors or microsatellite profile.  相似文献   

Epidemiological study on Mycoplasma synoviae infection in layers     

Dufour-Gesbert F  Dheilly A  Marois C  Kempf I 《Veterinary microbiology》2006,114(1-2):148-154

Mycoplasma synoviae infection occurs worldwide in commercial poultry flocks and may result in severe economic losses. The prevalence of this mycoplasma in standard layers older than 60 weeks was studied in a French department and the characteristics of infected or free flocks were compared. The genomic profiles of isolates from 36 infected flocks were studied by pulsed-field gel electrophoresis and random amplified polymorphic DNA methods in order to investigate possible routes of transmission. The minimum inhibitory concentrations of antibiotics were determined. Results showed that infection was more frequent in multi-age farms. Egg production and mortality of infected flocks were respectively lower and higher than in non-infected flocks but the differences were not statistically significant. The genomic profiles of isolates were quite homogeneous, a feature which does not facilitate the understanding of routes of transmission. All isolates were susceptible to tetracyclines, macrolides (except erythromycin), spectinomycin and fluoroquinolones.  相似文献   

Application of stable carbon isotope analysis to the detection of testosterone administration to cattle     

Hebestreit M  Flenker U  Buisson C  Andre F  Le Bizec B  Fry H  Lang M  Weigert AP  Heinrich K  Hird S  Schänzer W 《Journal of agricultural and food chemistry》2006,54(8):2850-2858

The use of anabolic substances is prohibited in food-producing animals throughout the European Union. No method is available to reliably detect the misuse of natural hormones in cattle. A method was developed to detect the abuse of testosterone in cattle fattening. Synthesized testosterone is rather depleted in the (13)C/(12)C ratio. Hence, the method is based on gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analysis of urine. To select testosterone metabolites and endogenous reference compounds (ERC), the concentration of urinary steroids of cattle was investigated. Dehydroepiandrosterone and androst-5ene-3beta,17alpha-diol were chosen as ERCs to show endogenous (13)C/(12)C ratios. Etiocholanolone and 5alpha-androstane-3beta,17alpha-diol were chosen as the most important testosterone metabolites. Other metabolites known from literature like epitestosterone were less promising. In principle, GC/C/IRMS is a nonspecific method because finally carbon dioxide is analyzed. Therefore, a dedicated cleanup procedure for the selected steroids was developed. By means of proposed confidence intervals in the isotopic composition of ERCs and metabolites, the administration of testosterone to cattle could be detected reliably. Differences of up to 11 per thousand on the delta-scale between ERC and testosterone metabolites were found after testosterone administration, whereas endogenous differences did not exceed 2 per thousand.  相似文献   

Tocopherol and ascorbate have contrasting effects on the viability of microencapsulated Lactobacillus rhamnosus GG     

Ying D  Sanguansri L  Weerakkody R  Singh TK  Leischtfeld SF  Gantenbein-Demarchi C  Augustin MA 《Journal of agricultural and food chemistry》2011,59(19):10556-10563

The antioxidants, sodium ascorbate and tocopherol, have contrasting effects on the viability of microencapsulated Lactobacillus rhamnosus GG (LGG) spray-dried powders during storage (4 and 25 °C; 32, 57, and 70% relative humidity). The addition of tocopherol improved probiotic viability during storage, while the incorporation of Na-ascorbate alone or in combination with tocopherol had detrimental effects on probiotic survival. The beneficial effect of tocopherol is a consequence of its chemical antioxidative action. The reduced viability in Na-ascorbate containing microcapsule formulations is hypothesized to be due primarily to the production of acetic acids arising from chemical degradation reactions and the catabolism of ascorbate by LGG. This study highlights the importance of considering the detrimental consequences of degradative chemical reactions and the metabolic fate of additives on the viability of probiotics when designing probiotic encapsulant formulations.  相似文献   

Quantification of five isoflavones and coumestrol in various solid agroenvironmental matrices using ¹³c₃-labeled internal standards     

Hoerger CC  Praplan AP  Becker L  Wettstein FE  Hungerbühler K  Bucheli TD 《Journal of agricultural and food chemistry》2011,59(3):847-856

We developed and validated three different sample preparation and extraction methods followed by HPLC-MS/MS (negative electrospray ionization) analysis for the quantification of estrogenic isoflavones (formononetin, daidzein, equol, biochanin A, and genistein) and coumestrol in red clover, soil, and manure. Plant and manure samples were solid-liquid extracted, whereas soil was extracted with accelerated solvent extraction. Absolute recoveries were between 80 and 93%, 20 and 30%, and 14 and 91% for plant, soil, and manure samples, respectively. Relative recoveries ranged from 75 to 105% for all matrices, indicating that isotope-labeled internal standards (13C?-formononetin, 13C?-daidzein, 13C?-equol, 13C?-biochanin A, and 13C?-genistein) were capable to compensate for losses during analysis. The limits of detection in red clover, soil, and manure were 3-9 μg/g(dryweight(dw)), 0.6-8.2 ng/g(dw), and 34.2 ng/g(dw) to 17.0 μg/g(dw), respectively. Formononetin was the most dominant compound in red clover plants (up to 12.5 mg/g(dw)) and soil (up to 3.3 μg/g(dw)), whereas equol prevailed in manure (up to 387 μg/g(dw)).  相似文献   

A 24-Year Retrospective Study of Equine Abortion in Normandy (France)     

Claire Laugier  Nathalie Foucher  Corinne Sevin  Albertine Leon  Jackie Tapprest 《Journal of Equine Veterinary Science》2011,31(3):116-123

The main causes of abortion in mares in France were studied from 1,822 cases submitted for necropsy. The cause of abortion was established in 74.9% of cases (n = 1,365). Fetoplacental infections (n = 869) represented 63.7% of diagnosed abortions. A noninfectious cause was found in 27.2% of cases (n = 496). Of the infectious causes of abortion, the vast majority were caused by bacteria (n = 695; 79.9%), followed by viruses (15.1%), and then fungi (1.8%). In 27 cases (3.1%), no specific pathogenic agent could be identified despite the presence of lesions. Of the noninfectious causes of abortion, umbilical cord abnormalities were the most frequent (n = 300; 60.5%). Placental villous hypoplasia represented the second most frequent cause (17.3%). This was followed by lethal congenital malformations (6.9%). The causes of placental insufficiency other than placental villous hypoplasia—twins, placental edema, placental premature separation, and body pregnancy—were less frequent. The diagnosis of equine abortion cases examined in Normandy seemed to be somewhat in agreement with the findings reported in Kentucky and the United Kingdom. In this study, about 60% of the cases were associated with a condition involving the allantochorion or the umbilical cord. Thus, to enhance diagnostic success, it is of prime importance to submit the fetal membranes along with the fetus for necropsy.  相似文献   

Association of fecal calprotectin concentrations with disease severity,response to treatment,and other biomarkers in dogs with chronic inflammatory enteropathies          下载免费PDF全文

Romy M. Heilmann  Nora Berghoff  Joanne Mansell  Niels Grützner  Nolie K. Parnell  Corinne Gurtner  Jan S. Suchodolski  Jörg M. Steiner 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(2):679-692

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Mineral nutrition of Gypsophila in vitro root culture     

Philippe Morard  Corinne Fulcheri  Max Henry 《Journal of plant nutrition》2013,36(4-5):717-730

Mineral nutrition of panicled gypsophila roots (Gypsophila paniculata L.) (Caryophyllaceae) cultivated in vitro in two media with different mineral composition, a classical Gamborg's B5 medium and a modified MH3 medium, was studied over a growth cycle of 28 days, by continuous measurement of mineral element consumption, without opening the culture flasks. The comparison between the total mineral element quantities consumed from media and those absorbed by roots at harvesting showed a good correspondence, proving the validity of the technique used and the absence of insolubilized mineral forms in the in vitro culture media. The mineral element composition of the MH3 medium was found to be better suited to Gypsophila paniculata root culture since all mineral nutrient elements are supplied in adequate quantities which are non‐limiting and non‐excessive. Culture on B5 medium showed that phosphorus (P) and copper (Cu) are probably the factors limiting growth and revealed an ammonium (NH₄ ⁺)/potassium (K⁺) ion antagonism. The in vitro roots, although uncoupled from the aerial part, behave like the roots of whole plants in several ways: the evolution of the medium pH corresponds to the form of the mineral nitrogen (N) consumed by the roots; sodium (Na) and chloride (Cl) are barely consumed and may be considered as non‐essential elements. Lastly, this in vitro root culturemodel makes itpossible to explain that the absorption of Na and Cl by the roots of whole plants is probably dependent on the transpiratory flow of the aerial part.  相似文献