Diversity of the Insect Visitors on Calluna vulgaris (Ericaceae) in Southern France Heathlands

As part of an ongoing research project on the pollination networks in European heathlands, the objective of this study was to assess the insect visitor guild on Calluna vulgaris (L.) Hull (Ericaceae). We focused the study on a region renowned for its largely well-preserved heathlands, the Cévennes National Park, Southern France. In 2013, flower visitors were observed over 3 d per site, in four heathland sites at mont Lozère. Honeybees (Apis mellifera L.) were the main visitors (62–88% of total visitors). Besides honeybees, a high diversity of visitors was detected with 57 different species identified (42 Diptera and 15 Hymenoptera). Hoverflies (Syrphidae, Diptera) visitors were abundant and diverse, especially individuals belonging to the genera Eristalis and Episyrphus. The reported diversity of visitors was probably due to the preservation of large heathland areas at mont Lozère and to the generalist pollination system of C. vulgaris.RESUME. Cette étude fait partie d’un projet de recherche en cours sur les réseaux de pollinisation dans les landes européennes. Son objectif est d’évaluer la guilde des insectes visiteurs de Calluna vulgaris (L.) Hull (Ericaceae). Cette étude se déroule dans une région réputée pour ses landes globalement bien préservées: le Parc natinal des Cévennes, situé dans le sud de la France. En 2013, les insectes visiteurs ont été observés durant trois jours par site, dans quatre sites au mont Lozère. Les abeilles domestiques (A. mellifera L.) sont les visiteurs principaux (62–88% du nombre total de visiteurs). Outre les abeilles domestiques, une diversité importante de visiteurs est constatée: 57 espèces ont été identifiées (42 appartenant à l''ordre des Diptères et 15 à l''ordre des Hyménoptères). Les syrphes (Syrphidae, Diptera) sont abondants et diversifiés, en particulier les genres Eristalis et Episyrphus. La diversité de visiteurs observée peut certainement s’expliquer par la préservation de grandes étendues de landes au mont Lozère et par le caractère généraliste de la pollinisation de la callune.     

Epipolythiodiketopiperazines from the Marine Derived Fungus Dichotomomyces cejpii with NF-κB Inhibitory Potential

The Ascomycota Dichotomomyces cejpii was isolated from the marine sponge Callyspongia cf. C. flammea. A new gliotoxin derivative, 6-acetylmonodethiogliotoxin (1) was obtained from fungal extracts. Compounds 2 and 3, methylthio-gliotoxin derivatives were formerly only known as semi-synthetic compounds and are here described as natural products. Additionally the polyketide heveadride (4) was isolated. Compounds 1, 2 and 4 dose-dependently down-regulated TNFα-induced NF-κB activity in human chronic myeloid leukemia cells with IC_50s of 38.5 ± 1.2 µM, 65.7 ± 2.0 µM and 82.7 ± 11.3 µM, respectively. The molecular mechanism was studied with the most potent compound 1 and results indicate downstream inhibitory effects targeting binding of NF-κB to DNA. Compound 1 thus demonstrates potential of epimonothiodiketopiperazine-derived compounds for the development of NF-κB inhibitors.     

A high virulence and pathotype diversity of Puccinia striiformis f.sp. tritici at its centre of diversity,the Himalayan region of Pakistan

Information on the pathogen virulence profile and diversity across locations is crucial for host germplasm improvement and deployment. The rapid acquisition of virulence to host resistance by the wheat yellow/stripe rust pathogen (Puccinia striiformis f.sp. tritici: PST), makes it crucial to know about its virulence and pathotype diversity. Recent studies have shown the plausible centre of origin of the pathogen in the Himalayan region, with Pakistan being the most ancestral to all other worldwide populations. To assess the status of virulence and pathotype diversity in the Himalayan region of Pakistan, a set of 127 PST infected wheat samples from eight locations were collected, multiplied and pathotyped using a set of 36 differential lines from the world set, European and Chinese sets, and 9 Avocet Yr isolines. Virulence (Vr) was recorded to 18 out of 24 tested yellow rust resistance (Yr) genes, while a total of 53 pathotypes were detected out of 127 isolates tested. Virulence was found to the resistance genes rarely deployed in Pakistan (Vr8) or even worldwide level (Vr5), while virulence to Vilmorin 23 (Yr3+) was absent in Pakistan, which is common in Europe. None of the pathotypes was dominant across all locations, however, no clear spatial structuring was observed for the studied locations. Our results suggested a high virulence and pathotype diversity in line with the previously proposed potential role of sexual recombination in the temporal maintenance of PST in the Himalayan region of Pakistan. This information should be useful in host resistance gene improvement and deployment.     

Development and characterization of a new set of 164 polymorphic EST‐SSR markers for diversity and breeding studies in rubber tree (Hevea brasiliensis Müll. Arg.)

Despite its economic importance and recent genome release, the need for molecular tools for Hevea brasiliensis is high. In the frame of a disease resistance study, EST sequences were retrieved from public database or generated by sequencing SSH libraries. Sequences were trimmed and microsatellite motifs searched using an ad hoc bioinformatic pipeline, and pairs of primers for the amplification of candidate markers were generated. We found a total of 10 499 unigenes from both sources of sequences, and 673 microsatellites motifs were detected using the default parameters of the pipeline. Two hundred sixty‐four primer pairs were tested and 226 (85.6%) successfully amplified. Out of the amplified candidate markers, 164 exhibited polymorphism. Relationships based on dendrograms using simple matching index and diversity statistics based on EST‐SSRs were compared with Genomic SSRs, showing the potentialities of EST‐derived microsatellites for resistance studies but also for population genetics approaches.     

Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO2

Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u_*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u_*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F_C) and change in storage (F_S) of CO₂ in the few hours after sundown. The sum of F_C and F_S reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R_Rmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F_c + F_s extrapolated to zero light, R_LRC, and (3) with a detailed process-based forest ecosystem model, R_cast. At most sites respiration rates estimated using the u_*-filter, R_ust, were smaller than R_Rmax and R_LRC. Agreement of our approach with independent measurements indicates that R_Rmax provides an excellent estimate of nighttime ecosystem respiration.     

多年生黑麦草叶片长度数量性状位点(QTLs)研究

选择固定有益等位基因,研究多年生黑麦草叶片长度数量性状位点,结果表明:与叶长最为相关的3个标记所表达的变异占表型总变异的50.9%(r2);在选择中如能将这3个标记最优化地组合在一起,其综合共同作用有望使叶片长度延长和缩短26 mm;鉴于供试材料在最初3个世代的群体选择中所估测到叶片长度的遗传力为0.32,这样在今后的选择工作中,即使只使用现有的两个标记,其效果亦优于传统的表型选择法.     

Characteristics and outcomes in surgical management of severe acute pancreatitis: 37 dogs (2001–2007)

Objective – Describe clinical characteristics and outcomes associated with canine patients undergoing surgical intervention for treatment of acute pancreatitis.
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis.     

Identification of risk factors for the prevalence and persistence of Salmonella in Belgian broiler chicken flocks

According to the European Food Safety Authority, salmonellosis is still one of the main causes of infectious foodborne gastroenteritis in humans. Broilers are an important source of salmonellosis after eggs and pork. Between 1987 and 1999 the trend of human salmonellosis incidence in Belgium increased constantly. However, from 2000 until 2005 a decrease in human cases was observed, probably following the sanitary measures implemented in the poultry breeder and laying sector. In order to decrease human infections it is essential to tackle the problem at the farm level to minimize cross-contamination from farm to fork. This paper seeks to answer two questions: (i) given the Salmonella status of the farm at a certain occasion (equal to the sampling time of the flock), what are the risk factors that the farm will be Salmonella positive at a following occasion? And (ii) what are the risk factors for a farm to be persistently positive for two consecutive flocks? We used surveillance data on 6824 broiler flocks studied for Salmonella infectivity from 2005 to 2006 in Belgium. The farms were tested regularly (3 weeks before slaughter of each broiler flock) for the presence of Salmonella based on multiple faecal samples per flock on a farm yielding clustered data. Generalized estimating equations, alternating logistic regression models, and random-intercept logistic regression models were employed to analyse these correlated binary data. Our results indicated that there are many factors that influence Salmonella risk in broiler flocks, and that they interact. Accounting for interactions between risk factors leads to an improved determination of those risk factors that increase infection with Salmonella. For the conditional analysis, the risk factors found to increase the risk of Salmonella infection on a farm at a current occasion given the previous Salmonella status included: Salmonella infection of day-old chicks (of the current flock); a previously infected flock even though the farm was equipped with a hygiene place to change clothes prior to entering the broiler house; having temporary workmen when there was a separation between birds of different species; and separating birds of different species in the Walloon region relative to the Flanders region. Sanitary measures such as a cleaning and disinfecting procedure conducted by an external cleaning firm, applying the all-in all-out procedure, and hand washing decreased the risk despite their interaction with other factors. From the joint analysis, the most important factors identified for increased risk for persistent Salmonella on a farm involved the interaction between having temporary workmen when there were poultry or farmers in contact with foreign poultry or persons, and the interaction between having temporary workmen when there were poultry or farmers in contact with external poultry or persons.