Models with only two predictor variables can accurately predict seed yield in diploid and tetraploid red clover     

Tim Vleugels  Bob Ceuppens  Gerda Cnops  Peter Lootens  Frederik R. D. van Parijs  Guy Smagghe  Isabel Roldán-Ruiz 《Euphytica》2016,209(2):507-523

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Interactive effects of organic acids in the rhizosphere     

Eva Oburger  Guy J.D. Kirk  Markus Puschenreiter 《Soil biology & biochemistry》2009,41(3):449-679

Organic acids released into the rhizosphere may perform many beneficial functions to the plant including metal detoxification and enhancement of nutrient acquisition. Typically, these organic acids are studied in isolation; however, roots simultaneously exude a cocktail of organic acids and other substances, and their combined impact on rhizosphere processes may be quite different. It has been hypothesized that some exudates may play secondary roles (e.g. inhibitors of microbial activity, blockage of sorption sites), which might enhance the longevity and nutrient-mobilization capacity of others. Here we investigated how the decomposition, sorption and P-solubilizing effects of citrate, malate and oxalate are affected by the presence of malonate and shikimate. We found that in a range of agricultural soils the decomposition of citrate, malate and oxalate was rapid, but not influenced by the presence of large quantities of shikimate or malonate. This suggests that the individual organic acids are taken up by different transport mechanisms or components of the microbial community. At large concentrations, malonate decreased sorption of citrate, malate and oxalate on the soil, whilst shikimate had little effect. The capacity of citrate, malate and oxalate to desorb P was significantly greater in cocktails containing malonate compared with the single organic acid; no effect was seen with shikimate. We conclude that neither malonate nor shikimate at realistic concentrations will significantly affect the biodegradation of citrate, malate or oxalate in the rhizosphere, and while malonate did enhance P desorption, this effect is additive rather than synergistic. Overall, we found little evidence that malonate and shikimate act as secondary regulators of citrate, malate and oxalate behavior in soil.  相似文献   

Amphoteric Surfactants for PAH and Lead Polluted-Soil Treatment Using Flotation     

Mouton  Julia  Mercier  Guy  Blais  Jean-François 《Water, air, and soil pollution》2009,199(1-4):381-387

Water, Air, & Soil Pollution - Nineteen soil samples (SE Spain) with very different chemical physical properties and developed over different parent materials were contaminated by adding...  相似文献   

Collaborative development of the Arrowsmith two node search interface designed for laboratory investigators     

Neil R Smalheiser  Vetle I Torvik  Amanda Bischoff-Grethe  Lauren B Burhans  Michael Gabriel  Ramin Homayouni  Alireza Kashef  Maryann E Martone  Guy A Perkins  Diana L Price  Andrew C Talk  Ruth West 《Journal of Biomedical Discovery and Collaboration》2006,1(1):8

Arrowsmith is a unique computer-assisted strategy designed to assist investigators in detecting biologically-relevant connections between two disparate sets of articles in Medline. This paper describes how an inter-institutional consortium of neuroscientists used the UIC Arrowsmith web interface http://arrowsmith.psych.uic.edu in their daily work and guided the development, refinement and expansion of the system into a suite of tools intended for use by the wider scientific community.  相似文献   

Ginkgo biloba Does—and Does Not—Prevent Acute Mountain Sickness     

Guy Leadbetter  Linda E. Keyes  Kirsten M. Maakestad  Sheryl Olson  Martha C. Tissot van Patot  Peter H. Hackett 《The Forestry Chronicle》2009,20(1):66-71

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Baseline demographics of a non‐native lake trout population and inferences for suppression from sensitivity‐elasticity analyses     

B. S. Cox  C. S. Guy  W. A. Fredenberg  L. R. Rosenthal 《Fisheries Management and Ecology》2013,20(5):390-400

Management agencies in several western states of the United States are implementing suppression programmes to control non‐native lake trout, Salvelinus namaycush (Walbaum), for the conservation of native species. This study was implemented to ascertain the population demographics of an expanding lake trout population and use those data to construct an age‐structured model to inform suppression efforts. Population projection matrices were used to model population growth and identify age or stage classes with the greatest influence on population growth. The size and age structure of lake trout sampled was skewed towards juveniles, indicating strong recruitment and a growing population. Matrix‐model simulations corroborated the observed size and age structure, as the lake trout population was predicted to grow exponentially (λ = 1.35, 95% CL: 1.25–1.43) with no suppression efforts. Elasticity analysis of matrix models indicated the relative contribution of survival rates to population growth among immature age classes was equal from age 0 to age at first maturity, but immature survival rates contributed more than adult survival and fertility rates. These results emphasise the importance of targeting juvenile lake trout for suppression efforts during exponential growth in recently established populations.  相似文献   

Polycyclic Aromatic Hydrocarbon Oxidation from Concentrates Issued from an Attrition Process of Polluted Soil Using the Fenton Reagent and Permanganate     

Malika Bendouz  Justine Dionne  Lan Huong Tran  Lucie Coudert  Guy Mercier  Jean-François Blais 《Water, air, and soil pollution》2017,228(3):115

This study was conducted to determine the optimal conditions for PAH degradation from highly contaminated attrition sludge (PAC) using a Fenton process or successive permanganate (KMnO₄) oxidation and Fenton processes. The following parameters were studied to optimize the Fenton oxidation process: the amounts of reactants based on the stoichiometric oxidant demand (SOD), the reactant addition protocol and number of doses, and the solid/liquid ratio (S/L). The results showed that the following conditions were optimum: TS?=?30%, 7.5 times SOD, H₂O₂/Fe²⁺ ratio?=?10, and added five times during 60 min, which allowed the degradation of 43% of total 27 PAHs from the PAC. Successive Fenton and KMnO₄ oxidation processes were also tested. PAH degradation using a sequential Fenton process followed by KMnO₄ oxidation (or KMnO₄ followed by Fenton) was higher than for the use of Fenton or KMnO₄ treatment alone. Up to 71% of the total 27 PAHs were degraded when using a combination of both processes. It appeared that the sequential treatment is a viable method for the significant degradation of 27 PAHs from PAC (t value?>?2.77).  相似文献   

Impact of Bacillus thuringiensis strains on survival,reproduction and foraging behaviour in bumblebees (Bombus terrestris)     

Veerle Mommaerts  Kris Jans  Guy Smagghe 《Pest management science》2010,66(5):520-525

BACKGROUND: Bacillus thuringiensis (Bt) and its protein crystals are used worldwide, either as a spray or when expressed in transgenic crops, for the control of pest insects. However, owing to their intensive use, there exists a debate regarding the involvement of this microbial insecticide in bee colony losses. In this study, in a tiered approach using laboratory microcolonies, an evaluation was made of the potential lethal and sublethal hazards on colony reproduction and foraging behaviour of workers of the bumblebee Bombus terrestris (L.) of two commercial Bt strains: kurstaki (Dipel^®) and aizawai (Xentari^®). Bumblebees, like honey bees, are intensively used in modern agriculture for pollination and fulfil a crucial role in the natural ecosystem. RESULTS: Exposure of bumblebees dermally or via treated pollen to either of the two Bt formulations at their field recommended rates (0.1%) caused no reduction in survival. However, when applied in the feeding sugar water, aizawai killed all workers at a concentration of 0.1%, but this lethal effect was lost at 0.01%. With respect to reproductive effects, kurstaki was harmless, while aizawai at 0.1% delivered in the feeding sugar water and pollen reduced reproduction by 100 and 31% respectively. Lower doses of 0.01% aizawai in the sugar water showed no more effect. In addition, kurstaki at 0.1% and aizawai at 0.01% in the feeding sugar water did not impair the foraging behaviour, resulting in normal nest colony performance. CONCLUSION: The results with kurstaki and aizawai demonstrated that, in general, the Bt strains are safe to B. terrestris bumblebees, although in some cases there were detrimental effects that depended on strain and route of exposure. In addition, the authors believe that to draw firm conclusions regarding the hazards of Bt to bumblebees would require more information on relevant concentrations of Bt products in the environment. Hence, routine testing for lethal and sublethal effects is recommended to ascertain combined use of Bt products and bumblebees in modern agriculture. Copyright © 2009 Society of Chemical Industry  相似文献   

Diuron mineralisation in a Mediterranean vineyard soil: impact of moisture content and temperature     

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   

Fusarium miscanthi and other Fusarium species as causal agents of Miscanthus × giganteus rhizome rot     

Jonathan Scauflaire  Mélanie Gourgue  Guy Foucart  Fabien Renard  Frédéric Vandeputte  Françoise Munaut 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(1):1-3

In 2010, Miscanthus × giganteus rhizomes were collected from Belgian fields showing emergence reduction and were analyzed for detection and identification of fungal species. All rhizomes were infected by at least one Fusarium species, of which F. culmorum, F. miscanthi, F. crookwellense and F. graminearum were the most abundant. Results of the pathogenicity tests by soil inoculation demonstrate the ability of F. miscanthi, F. culmorum and F. avenaceum to cause rhizome rot disease under greenhouse conditions. This is the first report of F. miscanthi and other Fusarium species isolated from M. × giganteus rhizomes in Belgium.  相似文献