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831.
Adeline Renier Philippe Jourand Sylvie Rapior Véréna Poinsot Abdoulaye Sy Bernard Dreyfus Lionel Moulin 《Soil biology & biochemistry》2008,40(6):1404-1412
Some legume species of the Crotalaria genus are specifically nodulated by methylotrophic bacteria belonging to the Methylobacterium nodulans species. The feature of this symbiotic bacterium is its ability to oxidize methanol, a property based on the presence of a methanol dehydrogenase enzyme. Despite a good knowledge of this property and its implication in symbiosis, the molecular dialogue between M. nodulans and crotalaria podocarpa leading to symbiosis is largely unknown, except the presence of a nodA nodulation gene in the genome of M. nodulans ORS 2060. To investigate if M. nodulans ORS 2060 produces Nod factors, molecules considered as the major bacteria-to-plant signals essential for the establishment of rhizobia–legume symbiosis, we identified and sequenced a nodDABCUIJHQ cluster from a genomic library of ORS 2060. Phylogenetic analyses of nod genes revealed that M. nodulans ORS 2060 form a branch together with Burkholderia tuberum STM678 and a strain of Methylobacterium sp. (4-46) isolated from Lotononis, and distinct from all the other rhizobia. To analyse the regulation of ORS 2060 nod genes, we constructed a nodA–LacZ promoter fusion to monitor the nod gene expression with various flavonoids. The flavone apigenin was found to be the strongest inducer of nod gene expression in M. nodulans ORS 2060. This latter flavonoid was used to induce ORS 2060, and Nod factors were purified by high-performance liquid chromatography (HPLC) and further characterized by mass spectrometry. One major Nod factor structure was identified as a pentamer of chitin substituted by C18:1 or C16:0 acyl chains on the non-reducing end and 6-O-sulphated on the other end, suggesting a classic symbiotic dialogue between M. nodulans and C. podocarpa. 相似文献
832.
Philippe Vain 《Journal of Cereal Science》2011,54(1):1-7
The combination of a tractable experimental system, molecular tools, facile genetics and comprehensive genomics resources places Brachypodium distachyon in a unique position to promote and accelerate biological investigations in cereal and grass crops. Brachypodium has a proven track-record as a bridge into Triticeae cereal crops by helping to navigate and assemble their large and complex genomes. Brachypodium’s compact genome already provides a useful reference for map-based cloning and comparative genomics. In this review, I argue that Brachypodium will also fulfill a more generic role as a functional genomics model. In this context, Brachypodium will play a pivotal role in multi-system approaches to underpin tomorrow’s grass research landscape. 相似文献
833.
Ahmed Mohareb Peter Sirmah Lyne Desharnais Stéphane Dumarçay Mathieu Pétrissans Philippe Gérardin 《Annals of Forest Science》2010,67(5):504-504
834.
Raimon Guitart Magda Sachana Francesca Caloni Siska Croubels Virginie Vandenbroucke Philippe Berny 《Veterinary journal (London, England : 1997)》2010,183(3):260-265
This review article is the third in a series on animal poisoning in Europe and represents a collation of published and non-published wildlife poisoning data from Belgium, France, Greece, Italy and Spain over the last 10 years. Birds, particularly waterfowl and raptors, were more commonly reported as victims of poisoning than wild mammals. In addition to specific but important toxicological disasters, deliberate primary or secondary poisonings are of concern to all countries. Metals (particularly lead arising from sporting/hunting activities) and pesticides (mainly anticholinesterases and anticoagulants) are frequent causes of poisoning, and often have fatal consequences. A more unified and consistent approach throughout European countries to improve the reporting and the analytical confirmation of wildlife poisoning would help to reduce the number of cases of malicious or negligent animal poisoning. 相似文献
835.
Raimon Guitart Siska Croubels Francesca Caloni Magda Sachana Franca Davanzo Virginie Vandenbroucke Philippe Berny 《Veterinary journal (London, England : 1997)》2010,183(3):249-254
The lack of a reference Veterinary Poison Control Centre for the European Union (EU) means that clinicians find it difficult to obtain information on poisoning episodes. This three-part review collates published and unpublished data obtained from Belgium, France, Greece, Italy and Spain over the last decade in order to provide a broader toxicoepidemiological perspective. The first article critically evaluates the national situation in the five European countries and concludes that information for livestock and poultry is limited and fragmentary compared to other animal groups. The analysis has revealed that clinical cases of poisoning are only occasionally studied in depth and that cattle are the species most frequently reported. Several plants and mycotoxins, a few pesticides and metals, together with contaminants of industrial origin, such as dioxins, are responsible for most of the recorded cases. 相似文献
836.
Mitzi K. Zarfoss Carrie B. Breaux† Herbert E. Whiteley Ralph E. Hamor Jodi A. Flaws‡ Philippe Labelle§ Richard R. Dubielzig¶ 《Veterinary ophthalmology》2010,13(1):4-13
Objective Pathologic intraocular neovascularization is a key component of many canine ophthalmic diseases such as uveitis, retinal detachment, intraocular neoplasms, and corneal perforation. The purpose of this study was to evaluate the structure of pre-iridal fibrovascular membranes (PIFMs) associated with several different disease processes and to identify specific factors associated with their development in the canine eye.
Procedure This study examined 36 enucleated canine eyes with the diagnosis of PIFM and one of the following: lens-induced uveitis, retinal detachment, iridociliary adenoma, corneal perforation, severe hyphema, or vitreal gliovascular membranes (canine ocular gliovascular syndrome, COGS). Three histologic stains and six immunohistochemical stains were performed in all 36 PIFM eyes and four histologically normal eyes, including: hematoxylin and eosin, alcian blue periodic acid schiff (PAS), Masson's trichrome, platelet endothelial cell adhesion molecule-1 (CD31), smooth muscle actin, vimentin, laminin, vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2).
Results Pre-iridal fibrovascular membrane extracellular matrix staining was consistent with collagen and mucins in all cases and positive for laminin in most cases. All PIFMs contained CD31-positive vessels and predominantly lymphoplasmacytic inflammation. Both PIFM vessels and spindle cells were positive for laminin, vimentin, smooth muscle actin, VEGF, and COX-2. Secondary intraocular pathology and immunohistochemical staining of other intraocular structures are also reported.
Conclusions Pre-iridal fibrovascular membrane morphology and immunohistochemical characteristics were similar across six canine disease processes, suggesting analogous pathophysiologic mechanisms. COX-2 and VEGF were identified using immunohistochemistry and may play a role in PIFM development. 相似文献
Procedure This study examined 36 enucleated canine eyes with the diagnosis of PIFM and one of the following: lens-induced uveitis, retinal detachment, iridociliary adenoma, corneal perforation, severe hyphema, or vitreal gliovascular membranes (canine ocular gliovascular syndrome, COGS). Three histologic stains and six immunohistochemical stains were performed in all 36 PIFM eyes and four histologically normal eyes, including: hematoxylin and eosin, alcian blue periodic acid schiff (PAS), Masson's trichrome, platelet endothelial cell adhesion molecule-1 (CD31), smooth muscle actin, vimentin, laminin, vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2).
Results Pre-iridal fibrovascular membrane extracellular matrix staining was consistent with collagen and mucins in all cases and positive for laminin in most cases. All PIFMs contained CD31-positive vessels and predominantly lymphoplasmacytic inflammation. Both PIFM vessels and spindle cells were positive for laminin, vimentin, smooth muscle actin, VEGF, and COX-2. Secondary intraocular pathology and immunohistochemical staining of other intraocular structures are also reported.
Conclusions Pre-iridal fibrovascular membrane morphology and immunohistochemical characteristics were similar across six canine disease processes, suggesting analogous pathophysiologic mechanisms. COX-2 and VEGF were identified using immunohistochemistry and may play a role in PIFM development. 相似文献
837.
The aphids Macrosiphum euphorbiae (Thomas) and Myzus persicae (Sulzer) (Hemiptera: Aphididae) are responsible for yield reduction in potato (Solanum tuberosum) production by direct phloem feeding and by spreading viruses. Breeding resistant traits from Solanum chomatophilum into the potato germplasm provides alternative means to control aphid infestations. Integrated pest management strategy, using plant resistance, benefits from the characterization of the resistance and of its impact on aphid biology. Our objective was to characterize the resistance of S. chomatophilum by assessing the effects of accessions, plant parts on aphid performance, and by assessing the impact of the resistance factors on different aphid developmental stages and on alate morph production. Detailed aphid performance was obtained by measuring fecundity, survival, percentage of nymphs that reached adult moult, and population growth using whole plant and clip cage experimental designs. Accession and plant physiological age, but not aphid developmental stage, influenced all life-history parameters, except for alate morph production which was not induced on the resistant accessions. Plant part influence was independent of plant species and accession. Both experimental designs resulted in congruent resistance levels at the accession level for each of the two aphid species, supporting the use of any of them in S. chomatophilum resistance screening. PI243340 was resistant to both aphid species, while PI365324 and PI310990 were also resistant to M. euphorbiae and M. persicae, respectively. 相似文献
838.
839.
Josselin Montarry Philippe Cartolaro Sylvie Richard-Cervera François Delmotte 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(1):61-70
The discovery of genetically distinct Erysiphe necator groups (A or B), with high phenotypic similarities, raises important questions about their coexistence. For plant pathogens,
niche partitioning, allowing the coexistence on the same host (i.e. the same resource), might result from separation in space and/or time. We used a landscape genetic approach to study the
geographic distribution of genetic groups of E. necator (distinguished by a SNP in the β-tubulin gene) at the spatial scale of the Languedoc-Roussillon region (southern France)
and to assess the temporal succession of groups along the course of the 2007 epidemic. Spatial distribution revealed a high
heterogeneity between vineyards: from 100% B to 100% A, with 62% and 38% of vineyards showing a majority of A and B isolates,
respectively. Temporal isolation seems to be the major mechanism in the coexistence of the two genetic groups: all isolates
collected towards the end of the epidemic belonged to group B, whatever the initial frequency of genetic groups. Our results
confirm that both A or B isolates can lead to flag-shoot symptoms, and showed that group A isolates tend to disappear during
the course of the epidemic, whereas group B isolates may be active during the entire epidemic and involved in further production
of cleistothecia, when recombination takes place. For the first time, the relationship between the frequency of genetic groups
and disease levels on leaves and clusters at the end of the epidemic was evaluated. We showed a strong relationship between
the disease severity and the genetic composition of E. necator populations: the damage was more important when the epidemic was initiated by B isolates. 相似文献
840.
Gwenaelle Comont Marie-France Corio-Costet Philippe Larignon François Delmotte 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(4):451-464
Phaeomoniella chlamydospora, (Chaetothyriales, Herpotrichiellaceae) is one of the main causal agents of Petri disease and esca on grapevines. We have
used AFLP markers to study the population genetic structure of 74 isolates collected at different spatial scales: 56 isolates
originated from vines with esca disease sampled from four French vineyards (Poitou-Charentes, Aquitaine, Languedoc-Roussillon,
Alsace); 18 isolates were collected from a single plot (Aquitaine vineyard). Significant linkage disequilibrium indicated
that P. chlamydospora populations are not panmictic, whereas the level of haplotypic diversity observed, 72 single multilocus haplotypes identified
in total among the 74 isolates analysed, suggest that reproduction in this species may not be strictly clonal. Clustering
analyses suggests the presence of two genetically differentiated but sympatric clusters of isolates. The level of differentiation
between the two clusters is high (F
ST = 0.23) and significant at 13 out of the 21 loci analyzed. The most plausible explanation for this pattern of admixture is
the coexistence in P. chlamydospora French populations of two predominant clonal lineages. Finally, the low level of spatial genetic differentiation in this
study is consistent with the spread of this fungus through the transport of infected plant material by human activities. 相似文献