The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform
Estelle Levetin - One of the best experts on this subject based on the ideXlab platform.
-
effect of sampling height on the concentration of airborne fungal Spores
Annals of Allergy Asthma & Immunology, 2008Co-Authors: Ahmed Khattab, Estelle LevetinAbstract:Background Spores of many fungal species have been documented as important aeroallergens. Airborne fungal Spores are commonly collected from the outdoor air at the rooftop level of high buildings; however, human exposure usually occurs nearer to the ground. It is necessary to estimate the concentration of airborne fungal Spores at the human breathing level to evaluate the actual human exposure to outdoor aeroallergens. Objective To compare the concentration of airborne fungal Spores at human respiration level (1.5 m above the ground) and at roof level (12 m height). Methods Air samples were collected using 2 Burkard volumetric 7-day recording Spore Traps from July 1 to October 31, 2005. One sampler was located on the roof of a building at the University of Tulsa at 12 m above ground, and the second sampler was placed in the courtyard of the building at 1.5 m. Burkard slides were analyzed for fungal Spores by light microscopy at a magnification of 1,000, and the results were statistically analyzed to compare the concentration of airborne fungal Spores at the 2 levels. Results The ground sampler had significantly higher concentration of basidioSpores, Penicillium/Aspergillus -type Spores, and smut Spores than the roof sampler. By contrast, the rooftop sampler registered significantly higher concentration of Alternaria , ascoSpores, and other Spores. Conclusions Ground level had significantly higher concentration of some important fungal aeroallergens but lower concentrations of others, suggesting that sampling height is one of the many variables that influence bioaerosol levels.
-
Preliminary studies on the effect of the Burkard alternate orifice on airborne fungal Spore concentrations
Aerobiologia, 2008Co-Authors: Ahmed Khattab, Estelle LevetinAbstract:The Burkard 7-day Spore trap with standard orifice is commonly used by researchers in sampling outdoor air. The alternate orifice is reported to have higher efficiency in collecting small airborne fungal Spores; however, no previous studies compared Burkard samplers with different orifices. This study was conducted to study the effect of the alternate orifice on the concentration of airborne fungal Spores. Air samples were collected from July to October 2005 with two Burkard Spore Traps, one had the standard orifice and the second had the alternate orifice. The two Spore Traps were located on the roof of a building (12 m height) at the University of Tulsa, Oklahoma. Burkard daily slides were analyzed for airborne Spores by light microscopy. The data from the two samplers were statistically analyzed using t -tests. The results indicated that the alternate orifice had significantly higher concentrations of Penicillium / Aspergillus -type Spores and basidioSpores than the standard orifice. By contrast, the standard orifice had significantly higher concentrations of Alternaria , ascoSpores, and other Spores than the alternate orifice. The alternate orifice can be used to increase the efficiency of trapping small Spores, which can be underestimated by using the standard orifice. However, additional comparison in other months of the year is recommended.
-
The air spora close to a compost facility in Northeast Oklahoma: Part I—Spore trap sampling
Aerobiologia, 2007Co-Authors: Scott Jefferson Gillum, Estelle LevetinAbstract:A compost facility in northeast Oklahoma is located relatively close to a residential area and is the focus of complaints about smell and concerns about health effects. Several species of Aspergillus have been known to cause health problems, and at least one of these species is dominant in compost. The atmosphere surrounding the compost facility was monitored for 1 year using Burkard Spore Traps to determine if there was a significant difference in Penicillium / Aspergillus type Spores concentration between a test and control site. Samplers were situated 710 m downwind for the test site and 6,085 m upwind at the control site. There was no significant difference in mean concentration of Penicillium / Aspergillus type Spores between the two sites ( t = 0.576 P > 0.05). The mean concentration of total Spores was significantly higher at the upwind control site ( t = −7.64, P
-
Comparison of pollen sampling with a Burkard Spore Trap and a Tauber Trap in a warm temperate climate
Grana, 2000Co-Authors: Estelle Levetin, Christine A Rogers, Stephen A. HallAbstract:Aerobiological data have been widely used by many scientists, including those that study modern flora as well as those wishing to reconstruct past vegetational associations. Burkard (Hirst-type) volumetric Spore Traps are widely used instruments for studying airborne pollen, while Tauber Traps are typically used to analyze pollen deposition. The present study compared the pollen collected by these two methods in Tulsa, Oklahoma a warm temperate area with year-round pollen. There was a strong correlation between the pollen influx from the Tauber Traps and cumulative sum of average daily airborne pollen concentrations recorded with the Burkard Spore trap over the course of 12 months from 1 Feb 1997 through 1 Feb 1998. The correlation coefficient between all taxa over the 12 months was 0.914; while the correlation coefficient for the monthly totals was 0.972. The data showed that both methods reflected local anemophilous vegetation although variations occurred in the prevalence recorded by both samplers.
Anne Legreve - One of the best experts on this subject based on the ideXlab platform.
-
Distribution of airborne inoculum of Gibberella zeae in Belgium
2020Co-Authors: Geraldine Dedeurwaerder, Maxime Duvivier, Marie Eve Renard, Viviane Van Hese, Pierre Hellin, Anne LegreveAbstract:Fusarium head blight (FHB) is a common fungal disease in winter wheat in Belgium causing yield losses and sanitary problems due to the production of mycotoxins by species associated to the disease. Fusarium graminearum (teleomorph Gibberalle zeae) is one of the important species involved in the species complex causing FHB and is able to produce wind dispersed ascoSpores by sexual reproduction. In order to analyse the distribution of airborne inoculum of G. zeae along the year and specially between heading and flowering and to understand the role of this inoculum in the infection of the ears, a network of Burkard Spore Traps was set up in fields in Walloon Region in Belgium during the cultural season 2011-2012. Total DNA from each fragment of Spore trap tape corresponding to 1 day sampling was extracted and the quantity of G. zeae was assessed using a real-time polymerase chain reaction (PCR) assay. First results showed the occurrence of G. zeae airborne inoculum between heading and flowering. The relationship between the distribution of airborne inoculum and the prevalence of G. zeae on infected ears collected in fields was studied in order to evaluate if Spore Traps coupled with real-time PCR can be used to improve the understanding of the epidemiology of FHB, the prediction of this disease and the control strategies.
-
Distribution of airborne Mycosphaerella graminicola inoculum at the field scale
Communications in agricultural and applied biological sciences, 2020Co-Authors: Maxime Duvivier, Geraldine Dedeurwaerder, Marie Eve Renard, Viviane Van Hese, G Marchal, Jean Marc Moreau, Anne LegreveAbstract:A network of 10 Burkard 7-day Spore-recording Traps was set up in the Walloon region in Belgium to monitor the airborne inoculum of wheat pathogens. Three Spore Traps were used to analyse the distribution of Mycosphaerella graminicola inoculum at the field scale, at 1 m above ground level. Two Traps were set up in a wheat field 100 m apart. The third trap was placed 70 m away in a sugar beet field adjacent to the wheat field. Total DNA from each fragment of Spore trap tape corresponding to 1 day sampling was extracted and the quantity of M. graminicola was assessed using real-time polymerase chain reaction (PCR) assay. The experiment was conducted from July to October 2009. Positive detections were obtained for between 33 and 36 days, depending on the Spore Traps. When detected, the daily quantities of cDNA, collected from a volume of 14.4 m3, fluctuated between 4.84E+00 and 6.10E+03. Correlation coefficients higher than 0,82 and no significant differences were observed between the quantities of M. graminicola collected by the three Spore Traps, indicating that, at 1 m above ground level, the distribution of inoculum can be considered as homogenous at the tested field scale. This study confirms that Spore Traps coupled with real-time PCR could be used to assess the airborne inoculum of M. graminicola and to understand the development of the disease at this scale.
-
Real-time PCR quantification and spatio-temporal distribution of airborne inoculum of Puccinia triticina in Belgium
European Journal of Plant Pathology, 2016Co-Authors: Maxime Duvivier, Geraldine Dedeurwaerder, Charlotte Bataille, Michel Proft, Anne LegreveAbstract:In order to better understand the epidemiology of Puccinia triticina and the relationship between airborne inoculum and disease severity, a method for quantifying airborne inoculum was developed using volumetric Burkard 7-day Spore Traps and real-time PCR. The method was applied using a Spore trap network from 1 March to 30 June over a 5-year period. At one site, the inoculum was quantified continuously over 3 years, during which it showed a seasonal distribution, with the highest quantities and detection frequencies occurring between May and June. High mean daily quantities (65.8–121.2 Spores/day) and detection frequencies (±20 % of days) were also reported after harvest from September to December. In the coldest months of the year, almost no detection was recorded (1–6 % of days). The study results indicate that the absence of inoculum in the air when upper leaves are emerging could be a limiting factor for the risk of epidemics. Mean daily quantities of airborne inoculum (0–131.4 Spores/day) were measured from the beginning of stem elongation (GS30) to the flag leaf stage (GS39). These values were well correlated with the disease severity levels measured during grain development. A multiple regression analysis showed that total rainfall in late summer and autumn and mean minimum temperature in winter positively influence Spore density between GS30 and GS39 in the following spring (R^2 = 0.73). This relationship and the patterns of airborne inoculum observed in fields strongly suggest the existence of a ‘green bridge’ phenomenon in Belgium. Our study also showed that the quantification of airborne inoculum or its estimation using a weather-based predictive model could be useful for interpreting disease severity models and avoiding over-estimates of disease risk.
-
Spore Traps network a new tool for predicting epidemics of wheat yellow rust
Communications in agricultural and applied biological sciences, 2011Co-Authors: Geraldine Dedeurwaerder, Maxime Duvivier, S M Mvuyenkure, Marie Eve Renard, Viviane Van Hese, G Marchal, Jean Marc Moreau, Anne LegreveAbstract:A network of Burkard 7-day Spore - recording Traps was set up in the Walloon Region in Belgium to monitor the airborne inoculum of wheat pathogens. The relationship between the airborne inoculum of Puccinia striiformis f.sp. tritici, the causal agent of stripe rust, and the disese incidence on plants in untreated plots locaed near each Spore Traps was studied during the 2008-2009 season. The presence of airborne inoculum was tested in four locations on tapes collected from the Burkard Spore Traps from 1 April to 14 June 2009. Total DNA from each fragment of Spore trap tape corresponding to 1 day sampling was extracted. P. striiformis f. sp. tritici was quantified by real-time polymerase chain reaction(PCR) assay using specific primers and SYBRGreen. The airborne inoculum of P.striiformis was frist detected between 7 and 13 April 2009, depending on the location in the Walloon Region. The first syptoms of sripe rust were observed in the fields between 15 May and 2 June 2009. The onset of the disease symptoms was always preceded by a higher peak of airborne inoculum about 15 days earlier. When P. striiformis f.sp. tritici was detected, the daily quantities of Spores, collected from a volume of air of 14.4m3, fluctuated between O.23 and 154.66. This study shows that Spore Traps coupled with realtime PCR could be used to assess the airborne inoculum of P. Striiformis in order to understand and predict stripe rust outbreaks?
C Calderon - One of the best experts on this subject based on the ideXlab platform.
-
Detection of airborne inoculum of Leptosphaeria maculans and Pyrenopeziza brassicae in oilseed rape crops by polymerase chain reaction (PCR) assays
Plant Pathology, 2002Co-Authors: C Calderon, S. J. Foster, Jackie Freeman, Elaine Ward, H. A. MccartneyAbstract:The potential use of DNA-based methods for detecting airborne inoculum of Leptosphaeria maculans and Pyrenopeziza brassicae, both damaging pathogens of oilseed rape, was investigated. A method for purifying DNA from Spores collected using Hirst-type Spore samplers and detecting it using polymerase chain reaction (PCR) assays is described. For both pathogens, the sensitivities of the DNA assays were similar for Spore-trap samples and pure Spore suspensions. As few as 10 Spores of L. maculans or P. brassicae could be detected by PCR and Spores of both species could be detected against a background of Spores of six other species. The method successfully detected Spores of P. brassicae collected using Spore Traps in oilseed rape crops that were infected with P. brassicae. Leptosphaeria maculans Spores were detected using Spore Traps on open ground close to L. maculans-infected oilseed rape stems. The potential use of PCR detection of airborne inoculum in forecasting the diseases caused by these pathogens is discussed.
-
detection of airborne fungal Spores sampled by rotating arm and hirst type Spore Traps using polymerase chain reaction assays
Journal of Aerosol Science, 2002Co-Authors: C Calderon, Jackie Freeman, Elaine Ward, Alastair MccartneyAbstract:AbstractConventional methods for detectingairborne fungal Spores rely on either optical identication orculturingand can be time consumingor unreliable. A method for purifyingDNA from conventionalSporesamplersanddetectingitusingpolymerasechainreaction(PCR)assaysisdescribed.Experimentswere done using Penicillium roqueforti. As few as 10 Spores could be detected in the PCR andP.roquefortiSporesweredetectedinabackgroundofSporesofsixotherunrelatedspecies.Themethodsuccessfully detected P. roqueforti Spores collected by rotatingarm and Hirst-type Spore Traps in windtunnel tests. The tests suggested that the detection limit was about 10 Spores or less in the PCR. FungalSpores were also detected in air samples collected in Mexico City usingfungal consensus primers, witha detection limit of about 200 Spores in the PCR. The potential for usingPCR-assays in conjunctionwith impactor samplers is discussed. c 2001 Elsevier Science Ltd. All rights reserved. 1. IntroductionBioaerosolsmaycausearangeofhealtheectsinhumansandanimals,dependingonthepre-dominant components present and their concentrations. Such eects include mucous membraneirritation, chronic bronchitis, allergic rhinitis and asthma, extrinsic allergic alveolitis (hyper-sensitivity pneumonitis), inhalation fever, humidier fever or organic dust toxic syndrome and
-
Seasonal and Diurnal Variation of Airborne Basidiomycete Spore Concentrations in Mexico City
Grana, 1995Co-Authors: C Calderon, H. A. Mccartney, John Lacey, Irma RosasAbstract:Abstract Seasonal and diurnal changes in concentrations of airborne basidiomycete Spores (basidioSpores, rusts, smuts) were studied, using Burkard volumetric Spore Traps, in two areas of Mexico City with different degrees of urbanization and related to changes in climatic variables through 1991. Basidiomycete Spores formed a large component of the total airborne fungal Spore load in the atmosphere of Mexico City. They were the second most abundant Spore type after Deuteromycotina (Hyphomycetes), forming 32% of the total fungal Spores trapped in an urban-residential area and 28% in an urban-commercial area. The most abundant basidiomycete Spores were basidioSpores although smut-type Spores were trapped on more days than basidioSpores and rusts on fewer. BasidioSpores occurred in concentrations up to 2,000 Spores m-3 in the urban-residential area. BasidioSpores showed a marked seasonal distribution, especially in the southern area, with their greatest abundance during the wet season. The correlation coeffic...
Alastair Mccartney - One of the best experts on this subject based on the ideXlab platform.
-
The collection and retention of a range of common airborne Spore types trapped directly into microtiter wells for enzyme-linked immunosorbent analysis
Journal of Aerosol Science, 2004Co-Authors: Alison Wakeham, Roy Kennedy, Alastair MccartneyAbstract:The collection and retention of a range of fungal Spores for a novel Spore trap (Microtiter immunoSpore trap (MTIST)), designed for use with immunoassays, was investigated in wind tunnel experiments. Concentrations of Spores of Botrytis cinerea, Cladosporium cladosporioides, Lycopodium clavatum, Erysiphe cruciferarum and Penicillium roqueforti, were measured usingthe MTIST and miniature suction Traps (same characteristics as a Burkard 7 day volumetric Spore trap). A clear relationship was observed between the Spore concentrations measure by the MTIST and those measured by the mini-suction Traps. No signi7cant (Fprob?0:4) effect of windspeed was observed for any Spore type in samples collected in the MTIST trap. There was some effect on windspeed in the collection of the larger Spore types (Lycopodium) as measured by the mini-suction Traps. Pre-coating microtiter wells of the MTIST Spore trap with a mixture of paraffin wax and petroleum jelly significantly increased the collection of the two largest Spore types. There were significant differences between the MTIST and the mini-suction Spore Traps in their ability to trap the smaller Spore types (Cladosporium and Penicillium). Employinga Botrytis-specific antiserum, a high level of correlation was observed between the numbers of Botrytis conidia trapped by the MTIST Spore trap and, corresponding absorbance values of an ELISA when, wells were pre-coated with either distilled water, poly-L-lysine or a petroleum jelly and paraffin wax mixture.
-
detection of airborne fungal Spores sampled by rotating arm and hirst type Spore Traps using polymerase chain reaction assays
Journal of Aerosol Science, 2002Co-Authors: C Calderon, Jackie Freeman, Elaine Ward, Alastair MccartneyAbstract:AbstractConventional methods for detectingairborne fungal Spores rely on either optical identication orculturingand can be time consumingor unreliable. A method for purifyingDNA from conventionalSporesamplersanddetectingitusingpolymerasechainreaction(PCR)assaysisdescribed.Experimentswere done using Penicillium roqueforti. As few as 10 Spores could be detected in the PCR andP.roquefortiSporesweredetectedinabackgroundofSporesofsixotherunrelatedspecies.Themethodsuccessfully detected P. roqueforti Spores collected by rotatingarm and Hirst-type Spore Traps in windtunnel tests. The tests suggested that the detection limit was about 10 Spores or less in the PCR. FungalSpores were also detected in air samples collected in Mexico City usingfungal consensus primers, witha detection limit of about 200 Spores in the PCR. The potential for usingPCR-assays in conjunctionwith impactor samplers is discussed. c 2001 Elsevier Science Ltd. All rights reserved. 1. IntroductionBioaerosolsmaycausearangeofhealtheectsinhumansandanimals,dependingonthepre-dominant components present and their concentrations. Such eects include mucous membraneirritation, chronic bronchitis, allergic rhinitis and asthma, extrinsic allergic alveolitis (hyper-sensitivity pneumonitis), inhalation fever, humidier fever or organic dust toxic syndrome and
Sylwester Masny - One of the best experts on this subject based on the ideXlab platform.
-
Influence of moisture on maturation rate of the Venturia inaequalis (Cooke) Wint. ascoSpores in central Poland
Journal of Plant Diseases and Protection, 2019Co-Authors: Paweł Jankowski, Sylwester MasnyAbstract:Influence of moisture on maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascoSpores was numerically examined using field data collected from Spore Traps in Skierniewice, Poland, during 2005–2008 and 2010–2014. In order to avoid a bias resulting from different abundance of airborne ascoSpores in different seasons, the cumulative proportions of mature ascoSpores observed in the season were analyzed. The maturation rate was expressed with the probit of cumulative proportion which linearized its sigmoidal shape and made the effect of the weather during the entire season of the same importance. The significant, positive association between the probit slope and the moisture indicators related to precipitation, leaf wetness, and high relative humidity were observed. Additionally, the significant, negative relationships with the average and maximal air temperature were found. The results suggested that rain should be treated as the major factor driving the ascoSpore development and leaf wetness as the second factor. In conclusion, the main sources of moisture should be taken into account in statistical models of ascoSpore development, but it seems reasonable to take into account different strength of their association with the development rate.
-
Comparison of mathematical models of maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascoSpores in central Poland
Journal of Plant Diseases and Protection, 2019Co-Authors: Paweł Jankowski, Sylwester MasnyAbstract:Models of maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascoSpores were compared using field data collected from Spore Traps in Skierniewice, Poland, during 2005–2008 and 2010–2014. Two sets of models describing ascoSpores maturation rate as a function of cumulative temperature were compared. The first set consisted of the “Stensvand” model with degrees summed during and 147 h after the rainfall, and the “Only” type models accumulating temperature only during hours with observed high moisture level indicated by rain, leaf wetness or high humidity. The second set consisted of more complex “All” type models proposed in the study, with degrees summed each hour, but differently weighted for periods with various sources of moisture such as rain, leaf wetness (LW) and relative air humidity (RH). The “All” type models proved to be superior over the “Only” type models. The “All Rain + LW + RH,” “All Rain + LW,” “All LW” and the “Stensvand” models gave the best match with the data. The final and most important result of the study is such that all of the examined models had high and unsatisfactory range of models’ uncertainty for the data from central Poland. Therefore, further improvements in modeling of ascoSpore maturation rate are necessary. Low accuracy of the models limits their practical application at the current stage of development.