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A collection of 241 isolates of Rhizoctonia solani obtained from potato plants grown in different areas in France was characterized for anastomosis grouping, symptomatology on tubers of different cultivars and sensitivity to three fungicides. Most isolates collected belonged to (anastomosis groups (AGs)) AG 3, but 2% and 4% of the isolates were AG 5 and AG 2-1. AG 3 and AG 2-1 isolates were mostly obtained from sclerotia on tubers, but all AG 5, some AG 3 and some AG 2-1 isolates were recovered from superficial tuber alterations, like deformations, corky or scabby lesions. Sclerotia were formed on tubers produced by healthy stem cuttings grown in soil artificially infested with AG 3, but not on tubers grown in soil infested with either AG 5 or AG 2-1. No variation in susceptibility to sclerotial formation was observed among five potato cultivars. In all cases, a large proportion of tubers showed superficial corky lesions, often associated with deformations. The proportion of tubers with lesions and deformations was highest in soil infested with AG 2-1 and significantly lower on cv. Samba in all treatments. All isolates were highly sensitive to flutolanil, iprodione and pencycuron, except the AG 5 isolates, moderately sensitive to pencycuron. These results show that, although AG 3 is the most common R. solani group on potato in France, AG 5 and AG 2-1 may be present. Isolates differed for pathogenicity. In vitro sensitivity to fungicides varied among AGs.  相似文献   
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Different methods have been developed to estimate evapotranspiration from remote sensing data, from empirical approaches such as the simplified relationship to complex methods based on remote sensing data assimilation along with SVAT models. The simplified relationship has been applied from small spatial scale using airborne TIR images to continental scale with NOAA data. Assimilation procedures often require remote sensing data over different spectral domains to retrieve input parameters which characterize surface properties such as albedo, emissivity or Leaf Area Index. A brief review of these different approaches is presented, with a discussion about the main physical bases and assumptions of various models. The paper reports also some examples and results obtained over the experimental area of the Alpilles Reseda project, where various types of models have been applied to estimate surface fluxes from remote sensing data.  相似文献   
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Nineteen phenolic compounds including hydroxybenzoic acids, hydroxycinnamic acids, flavonoids, phenolic alcohols, and phenolic aldehydes have been identified and quantified in two monovarietal champagnes, Chardonnay and Pinot Noir, by using a reverse-phase high-performance liquid chromatography (HPLC) system coupled with diode array detection. The identification of four hydroxycinnamic tartaric esters (caftaric, coutaric, fertaric, and 2-S-glutathionylcaftaric acids), two flavanonols (astilbin and engeletin), and some other compounds was confirmed by HPLC coupled with mass spectrometry. Caftaric acid and tyrosol were the major phenols. Hydroxybenzoic acids and flavonoids were present at low concentrations. The phenolic compositions of 2000 and 2001 Chardonnay and Pinot Noir vary quantitatively according to the year and the variety, but the chemical natures of the molecules are the same. The total phenolic content determined by colorimetric measurement ranges from 176 to 195 mg/L of gallic acid equivalent and is similar to that described in white wines.  相似文献   
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The aim of this study was to evaluate the effects of diets containing rice distillers’ by‐product (RDP) on growth performance, carcass characteristics, meat quality, and gut microbiota of fattening pigs. Twenty‐four crossbred finishing pigs (Duroc × Landrace × Yorkshire), 56.9 ± 3.1 kg initial body weight, were randomly allocated to three groups. For 56 days, pigs were fed one of three diets including RDP0 (control), RDP15 (15% RDP in DM), and RDP30 (30% RDP in DM). With RDP level in diet, average daily gain and backfat thickness linearly increased (p < 0.05), and drip loss tended to increase (p ≤ 0.08). In addition, 16S ribosomal RNA gene amplicon profiling showed that RDP was associated with modulation of colonic microbiota composition, especially at family and genus levels. Relative abundance of Porphyromonadaceae and Erysipelotrichaceae families in colonic digesta increased with inclusion of RDP, while that of Enterobacteriaceae decreased. The proportion of genera unclassified Erysipelotrichaceae, and Butyrivibrio increased as inclusion of RDP. These results indicate that up to 30% inclusion in diet of finishing pigs, RDP can modulate colonic microbiota composition, and induces an improvement of animal growth and fat deposition.  相似文献   
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Musa sp. peels are widely used by smallholders as complementary feeds for cattle in the tropics. A study of the influence of the variety and the maturation stage of the fruit on fermentability and metabolisable energy (ME) content of the peels was performed using banana (Yangambi Km5) and plantain (Big Ebanga) peels at three stages of maturation in an in vitro model of the rumen. Peel samples were analysed for starch, free sugars and fibre composition. Samples were incubated in the presence of rumen fluid. Kinetics of gas production were modelled, ME content was calculated using prediction equation and short-chain fatty acids production and molar ratio were measured after 72 h of fermentation. Final gas production was higher in plantain (269–339 ml g−1) compared to banana (237–328 ml g−1) and plantain exhibited higher ME contents (8.9–9.7 MJ/kg of dry matter, DM) compared to banana (7.7–8.8 MJ/kg of DM). Butyrate molar ratio decreased with maturity of the peels. The main influence of the variety and the stage of maturation on all fermentation parameters as well as ME contents of the peels was correlated to changes in the carbohydrate fraction of the peels, including starch and fibre.  相似文献   
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