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Emaga Thomas Happi Bindelle Jérôme Agneesens Richard Buldgen André Wathelet Bernard Paquot Michel 《Tropical animal health and production》2011,43(1):171-177
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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Anne Moussart Caroline Onfroy Angelique Lesne Magali Esquibet Eric Grenier Bernard Tivoli 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(1):57-69
Ditylenchus dipsaci, the stem nematode of alfalfa (Medicago sativa), Mycosphaerella pinodes, cause of Ascochyta blight in pea (Pisum sativum) and Aphanomyces euteiches, cause of pea root rot, result in major yield losses in French alfalfa and pea crops. These diseases are difficult to control
and the partial resistances currently available are not effective enough. Medicago truncatula, the barrel medic, is the legume model for genetic studies, which should lead to the identification and characterization
of new resistance genes for pathogens. We evaluated a collection of 34 accessions of M. truncatula and nine accessions from three other species (two from M. italica, six from M. littoralis and one from M. polymorpha) for resistance to these three major diseases. We developed screening tests, including standard host references, for each
pathogen. Most of the accessions tested were resistant to D. dipsaci, with only three accessions classified as susceptible. A very high level of resistance to M. pinodes was observed among the accessions, none of which was susceptible to this pathogen. Conversely, a high level of variation,
from resistant to susceptible accessions, was identified in response to infection by A. euteiches. 相似文献
16.
Talaat El Sebaı Marion Devers Bernard Lagacherie Nadine Rouard Guy Soulas Fabrice Martin‐Laurent 《Pest management science》2010,66(9):988-995
BACKGROUND: The diuron‐mineralising ability of the microbiota of a Mediterranean vineyard soil exposed each year to this herbicide was measured. The impact of soil moisture and temperature on this microbial activity was assessed. RESULTS: The soil microbiota was shown to mineralise diuron. This mineralising activity was positively correlated with soil moisture content, being negligible at 5% and more than 30% at 20% soil moisture content. According to a double Gaussian model applied to fit the dataset, the optimum temperature/soil moisture conditions were 27.9 °C/19.3% for maximum mineralisation rate and 21.9 °C/18.3% for maximum percentage mineralisation. The impact of temperature and soil moisture content variations on diuron mineralisation was estimated. A simulated drought period had a suppressive effect on subsequent diuron mineralisation. This drought effect was more marked when higher temperatures were used to dry (40 °C versus 28 °C) or incubate (28 °C versus 20 °C) the soil. The diuron kinetic parameters measured after drought conditions were no longer in accordance with those estimated by the Gaussian model. CONCLUSION: Although soil microbiota can adapt to diuron mineralisation, its activity is strongly dependent on climatic conditions. It suggests that diuron is not rapidly degraded under Mediterranean climate, and that arable Mediterranean soils are likely to accumulate diuron residues. Copyright © 2010 Society of Chemical Industry 相似文献
17.
Bréard E Sailleau C Coupier H Mure-Ravaud K Hammoumi S Gicquel B Hamblin C Dubourget P Zientara S 《Veterinary research》2003,34(6):777-789
Bluetongue (BT) virus serotype 2 (BTV 2) was first confirmed in Tunisia in February 2000 and has since spread northward and westward, infecting several other countries and islands, including Corsica, where clinical disease was reported in October 2000. BT was again reported on the Island in July 2001, some six months after a vaccination campaign against BTV 2. The molecular relationship between isolates of the BTV 2 Corsican wild-type viruses from 2000 and 2001, and the attenuated BTV 2 vaccine were determined by comparing corresponding sequences of genome segments 2, 7 and 10 with each other and with already published sequences available in the genome database. Complete genetic stability was observed between the isolates of the Corsican BTV 2. There was some divergence between the nucleotide sequences of segment 10 obtained from the wild-type and vaccine virus strains. Based on these differences, primers were selected that could be used in RT-PCR to differentiate between the wild-type and the vaccine viruses. 相似文献
18.
Michael W. Mullowney Eoghainín ó hAinmhire Anam Shaikh Xiaomei Wei Urszula Tanouye Bernard D. Santarsiero Joanna E. Burdette Brian T. Murphy 《Marine drugs》2014,12(6):3574-3586
As part of our program to identify novel secondary metabolites that target drug-resistant ovarian cancers, a screening of our aquatic-derived actinomycete fraction library against a cisplatin-resistant ovarian cancer cell line (OVCAR5) led to the isolation of novel diaza-anthracene antibiotic diazaquinomycin E (DAQE; 1), the isomeric mixture of diazaquinomycin F (DAQF; 2) and diazaquinomycin G (DAQG; 3), and known analog diazaquinomycin A (DAQA; 4). The structures of DAQF and DAQG were solved through deconvolution of X-Ray diffraction data of their corresponding co-crystal. DAQE and DAQA exhibited moderate LC50 values against OVCAR5 of 9.0 and 8.8 μM, respectively. At lethal concentrations of DAQA, evidence of DNA damage was observed via induction of apoptosis through cleaved-PARP. Herein, we will discuss the isolation, structure elucidation, and biological activity of these secondary metabolites. 相似文献
19.
Magali Geay Véronique Marchetti André Clément Bernard Loubinoux Philippe Gérardin 《Journal of Wood Science》2000,46(4):331-333
New materials containing carboxylate groups have been synthesized by grafting polyacrylic acid onto sawdust. These new adsorbents were subjected to continuous extraction of different metal ions using packed columns to determine their maximum binding capacities. They exhibit binding capacities 15–40 times higher than unmodified sawdusts for removal of Cu2+, Ni2+, and Cd2+ chosen as representative heavy metal ions. Cation desorption and adsorbent regeneration could be effected by elution with a diluted HCl solution; water as an eluent has no effect on metal desorption. 相似文献
20.
Julien Ruelle Jacques Beauchene Anne Thibaut Bernard Thibaut 《Annals of Forest Science》2007,64(5):503-510
On 10 trees from 10 species of French Guyana tropical rainforest in a clear active process of restoring verticality growth strains were measured in situ in order to determine the occurrence of tension wood within samples. Wood specimens were cut in the vicinity of the growth strains measurements in order to measure some mechanical and physical properties. As suspected, tensile growth strains was very much higher in tension wood zone, because longitudinal modulus of elasticity was slightly higher. Longitudinal shrinkage was also much higher in tension wood than in opposite wood. 相似文献