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Sample records for birch pollen isoallergens

  1. The influence of recombinant production on the immunologic behavior of birch pollen isoallergens.

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    Michael Wallner

    Full Text Available BACKGROUND: Allergic reactions towards the birch major pollen allergen Bet v 1 are among the most common causes of spring pollinosis in the temperate climate zone of the Northern hemisphere. Natural Bet v 1 is composed of a complex mixture of different isoforms. Detailed analysis of recombinant Bet v 1 isoforms revealed striking differences in immunologic as well as allergenic properties of the molecules, leading to a classification of Bet v 1 isoforms into high, medium, and low IgE binding proteins. Especially low IgE binding Bet v 1 isoforms have been described as ideal candidates for desensitizing allergic patients with allergen specific immunotherapy (SIT. Since diagnosis and therapy of allergic diseases are highly dependent on recombinant proteins, continuous improvement of protein production is an absolute necessity. METHODOLOGY: Therefore, two different methods for recombinant production of a low IgE binding Bet v 1 isoform were applied; one based on published protocols, the other by implementing latest innovations in protein production. Both batches of Bet v 1.0401 were extensively characterized by an array of physicochemical as well as immunological methods to compare protein primary structure, purity, quantity, folding, aggregation state, thermal stability, and antibody binding capacity. CONCLUSION: The experiments demonstrated that IgE antibody binding properties of recombinant isoallergens can be significantly influenced by the production method directly affecting possible clinical applications of the molecules.

  2. Efficacy of recombinant birch pollen vaccine for the treatment of birch-allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Pauli, Gabrielle; Larsen, Tina H; Rak, Sabina

    2008-01-01

    BACKGROUND: Recombinant DNA technology has the potential to produce allergen-specific immunotherapy vaccines with defined composition. OBJECTIVE: To evaluate the effectiveness of a new recombinant birch pollen allergen vaccine in patients with birch pollen allergy. METHODS: A multicenter......, randomized, double-blind, placebo-controlled trial was undertaken to compare the following 3 vaccines in 134 adults with birch pollen allergy: recombinant birch pollen allergen vaccine (rBet v 1a), licensed birch pollen extract, natural purified birch pollen allergen (nBet v 1), and placebo. Patients...

  3. Quantitative DNA Analyses for Airborne Birch Pollen.

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    Isabell Müller-Germann

    Full Text Available Birch trees produce large amounts of highly allergenic pollen grains that are distributed by wind and impact human health by causing seasonal hay fever, pollen-related asthma, and other allergic diseases. Traditionally, pollen forecasts are based on conventional microscopic counting techniques that are labor-intensive and limited in the reliable identification of species. Molecular biological techniques provide an alternative approach that is less labor-intensive and enables identification of any species by its genetic fingerprint. A particularly promising method is quantitative Real-Time polymerase chain reaction (qPCR, which can be used to determine the number of DNA copies and thus pollen grains in air filter samples. During the birch pollination season in 2010 in Mainz, Germany, we collected air filter samples of fine (<3 μm and coarse air particulate matter. These were analyzed by qPCR using two different primer pairs: one for a single-copy gene (BP8 and the other for a multi-copy gene (ITS. The BP8 gene was better suitable for reliable qPCR results, and the qPCR results obtained for coarse particulate matter were well correlated with the birch pollen forecasting results of the regional air quality model COSMO-ART. As expected due to the size of birch pollen grains (~23 μm, the concentration of DNA in fine particulate matter was lower than in the coarse particle fraction. For the ITS region the factor was 64, while for the single-copy gene BP8 only 51. The possible presence of so-called sub-pollen particles in the fine particle fraction is, however, interesting even in low concentrations. These particles are known to be highly allergenic, reach deep into airways and cause often severe health problems. In conclusion, the results of this exploratory study open up the possibility of predicting and quantifying the pollen concentration in the atmosphere more precisely in the future.

  4. Quantitative DNA Analyses for Airborne Birch Pollen.

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    Müller-Germann, Isabell; Vogel, Bernhard; Vogel, Heike; Pauling, Andreas; Fröhlich-Nowoisky, Janine; Pöschl, Ulrich; Després, Viviane R

    2015-01-01

    Birch trees produce large amounts of highly allergenic pollen grains that are distributed by wind and impact human health by causing seasonal hay fever, pollen-related asthma, and other allergic diseases. Traditionally, pollen forecasts are based on conventional microscopic counting techniques that are labor-intensive and limited in the reliable identification of species. Molecular biological techniques provide an alternative approach that is less labor-intensive and enables identification of any species by its genetic fingerprint. A particularly promising method is quantitative Real-Time polymerase chain reaction (qPCR), which can be used to determine the number of DNA copies and thus pollen grains in air filter samples. During the birch pollination season in 2010 in Mainz, Germany, we collected air filter samples of fine (<3 μm) and coarse air particulate matter. These were analyzed by qPCR using two different primer pairs: one for a single-copy gene (BP8) and the other for a multi-copy gene (ITS). The BP8 gene was better suitable for reliable qPCR results, and the qPCR results obtained for coarse particulate matter were well correlated with the birch pollen forecasting results of the regional air quality model COSMO-ART. As expected due to the size of birch pollen grains (~23 μm), the concentration of DNA in fine particulate matter was lower than in the coarse particle fraction. For the ITS region the factor was 64, while for the single-copy gene BP8 only 51. The possible presence of so-called sub-pollen particles in the fine particle fraction is, however, interesting even in low concentrations. These particles are known to be highly allergenic, reach deep into airways and cause often severe health problems. In conclusion, the results of this exploratory study open up the possibility of predicting and quantifying the pollen concentration in the atmosphere more precisely in the future.

  5. Quality Control of Biomedicinal Allergen Products - Highly Complex Isoallergen Composition Challenges Standard MS Database Search and Requires Manual Data Analyses.

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    Jelena Spiric

    Full Text Available Allergy against birch pollen is among the most common causes of spring pollinosis in Europe and is diagnosed and treated using extracts from natural sources. Quality control is crucial for safe and effective diagnosis and treatment. However, current methods are very difficult to standardize and do not address individual allergen or isoallergen composition. MS provides information regarding selected proteins or the entire proteome and could overcome the aforementioned limitations. We studied the proteome of birch pollen, focusing on allergens and isoallergens, to clarify which of the 93 published sequence variants of the major allergen, Bet v 1, are expressed as proteins within one source material in parallel. The unexpectedly complex Bet v 1 isoallergen composition required manual data interpretation and a specific design of databases, as current database search engines fail to unambiguously assign spectra to highly homologous, partially identical proteins. We identified 47 non-allergenic proteins and all 5 known birch pollen allergens, and unambiguously proved the existence of 18 Bet v 1 isoallergens and variants by manual data analysis. This highly complex isoallergen composition raises questions whether isoallergens can be ignored or must be included for the quality control of allergen products, and which data analysis strategies are to be applied.

  6. Quality Control of Biomedicinal Allergen Products - Highly Complex Isoallergen Composition Challenges Standard MS Database Search and Requires Manual Data Analyses.

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    Spiric, Jelena; Engin, Anna M; Karas, Michael; Reuter, Andreas

    2015-01-01

    Allergy against birch pollen is among the most common causes of spring pollinosis in Europe and is diagnosed and treated using extracts from natural sources. Quality control is crucial for safe and effective diagnosis and treatment. However, current methods are very difficult to standardize and do not address individual allergen or isoallergen composition. MS provides information regarding selected proteins or the entire proteome and could overcome the aforementioned limitations. We studied the proteome of birch pollen, focusing on allergens and isoallergens, to clarify which of the 93 published sequence variants of the major allergen, Bet v 1, are expressed as proteins within one source material in parallel. The unexpectedly complex Bet v 1 isoallergen composition required manual data interpretation and a specific design of databases, as current database search engines fail to unambiguously assign spectra to highly homologous, partially identical proteins. We identified 47 non-allergenic proteins and all 5 known birch pollen allergens, and unambiguously proved the existence of 18 Bet v 1 isoallergens and variants by manual data analysis. This highly complex isoallergen composition raises questions whether isoallergens can be ignored or must be included for the quality control of allergen products, and which data analysis strategies are to be applied.

  7. Quality Control of Biomedicinal Allergen Products – Highly Complex Isoallergen Composition Challenges Standard MS Database Search and Requires Manual Data Analyses

    Science.gov (United States)

    Spiric, Jelena; Engin, Anna M.; Karas, Michael; Reuter, Andreas

    2015-01-01

    Allergy against birch pollen is among the most common causes of spring pollinosis in Europe and is diagnosed and treated using extracts from natural sources. Quality control is crucial for safe and effective diagnosis and treatment. However, current methods are very difficult to standardize and do not address individual allergen or isoallergen composition. MS provides information regarding selected proteins or the entire proteome and could overcome the aforementioned limitations. We studied the proteome of birch pollen, focusing on allergens and isoallergens, to clarify which of the 93 published sequence variants of the major allergen, Bet v 1, are expressed as proteins within one source material in parallel. The unexpectedly complex Bet v 1 isoallergen composition required manual data interpretation and a specific design of databases, as current database search engines fail to unambiguously assign spectra to highly homologous, partially identical proteins. We identified 47 non-allergenic proteins and all 5 known birch pollen allergens, and unambiguously proved the existence of 18 Bet v 1 isoallergens and variants by manual data analysis. This highly complex isoallergen composition raises questions whether isoallergens can be ignored or must be included for the quality control of allergen products, and which data analysis strategies are to be applied. PMID:26561299

  8. Molecular Ice Nucleation Activity of Birch Pollen

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    Felgitsch, Laura; Bichler, Magdalena; Häusler, Thomas; Weiss, Victor U.; Marchetti-Deschmann, Martina; Allmaier, Günter; Grothe, Hinrich

    2015-04-01

    Heterogeneous ice nucleation plays a major part in ecosystem and climate. Due to the triggering of ice cloud formation it influences the radiation balance of the earth, but also on the ground it can be found to be important in many processes of nature. So far the process of heterogeneous ice nucleation is not fully understood and many questions remain to be answered. Biological ice nucleation is hereby from great interest, because it shows the highest freezing temperatures. Several bacteria and fungi act as ice nuclei. A famous example is Pseudomonas syringae, a bacterium in commercial use (Snomax®), which increases the freezing from homogeneous freezing temperatures of approx. -40° C (for small volumes as in cloud droplets) to temperatures up to -2° C. In 2001 it was found that birch pollen can trigger ice nucleation (Diehl et al. 2001; Diehl et al. 2002). For a long time it was believed that this is due to macroscopic features of the pollen surface. Recent findings of Bernhard Pummer (2012) show a different picture. The ice nuclei are not attached on the pollen surface directly, but on surface material which can be easily washed off. This shows that not only the surface morphology, but also specific molecules or molecular structures are responsible for the ice nucleation activity of birch pollen. With various analytic methods we work on elucidating the structure of these molecules as well as the mechanism with which they trigger ice nucleation. To solve this we use various instrumental analytic techniques like Nuclear Magnetic Resonance spectroscopy (NMR), Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS), and Gas-phase Electrophoretic Mobility Molecular Analysis (GEMMA). Also standard techniques like various chromatographic separation techniques and solvent extraction are in use. We state here that this feature might be due to the aggregation of small molecules, with agglomerates showing a specific surface structure. Our results

  9. Birch pollen allergy: molecular characterization and hypoallergenic products

    NARCIS (Netherlands)

    Schenk, M.F.

    2008-01-01

    Allergic diseases, such as hay fever and food allergy, affect a substantial part of the population in westernized countries. Pollen of the European white birch (Betula pendula) is a considerable cause of hay fever (seasonal allergic rhinitis) in northern and central Europe. The major birch pollen al

  10. Fluctuation of birch (Betula L. pollen seasons in Poland

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    Małgorzata Puc

    2015-12-01

    Full Text Available Birch pollen grains are one of the most important groups of atmospheric biological particles that induce allergic processes. The fluctuation pattern of birch pollen seasons in selected cities of Poland is presented. Measurements were performed by the volumetric method (Burkard and Lanzoni 2000 pollen samplers. The distributions of the data were not normal (Shapiro–Wilk test and statistical error risk was estimated at a significance level of α = 0.05. Pollen season was defined as the period in which 95% of the annual total catch occurred. The linear trend for the selected features of the pollen season, skewness, kurtosis and coefficient of variation (V% were also analyzed. During the 12–14 years of study, the beginnings of birch pollen seasons were observed 7–14 days earlier, the ends were noted 5–10 days earlier, and the days with maximum values occurred 7–14 days earlier compared to the long-term data. The left-skewed distribution of the pollen season starts in most sampling sites confirms the short-lasting occurrence of pollen in the air. The threat of birch pollen allergens was high during the pollen seasons. If vegetation is highly diverse, flowering and pollen release are extended in time, spread over different weeks and occur at different times of the day. Flowering time and pollen release are affected by insolation, convection currents, wind, and turbulence. Therefore, pollen seasons are characterized by great inter-annual variability.

  11. Food allergy to apple and specific immunotherapy with birch pollen

    DEFF Research Database (Denmark)

    Hansen, Kirsten Skamstrup; Khinchi, Marianne Søndergaard; Skov, Per Stahl

    2004-01-01

    Conflicting results concerning the effect of specific pollen immunotherapy (SIT) on allergy to plant foods have been reported. The aim of this study was to investigate the effect of SIT using a birch pollen extract on food allergy with focus on allergy to apple. Seventy-four birch pollen......-allergic patients were included in a double-blind, double-dummy, and placebo-controlled comparison of sublingual-swallow (SLIT) and subcutaneous (SCIT) administration of a birch pollen extract. Sixty-nine percent of these patients reported allergy to apple. The clinical reactivity to apple was evaluated by open....... Therefore, oral allergy syndrome (OAS) to apple should not be considered as a main criterion for selecting patients for birch pollen immunotherapy at present....

  12. Allergens from birch pollen and pollen of the European chestnut share common epitopes.

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    Hirschwehr, R; Jäger, S; Horak, F; Ferreira, F; Valenta, R; Ebner, C; Kraft, D; Scheiner, O

    1993-09-01

    Type I allergy to pollen of the European chestnut (Castanea sativa) represents a major cause of pollinosis in (sub) Mediterranean areas. Using sera from 14 patients with established allergy to pollen of the European chestnut, 13/14 sera (92%) showed IgE-binding to a 22 kD protein, 2/14 (14%) displayed additional binding to a 14 kD protein and 1/14 (7%) bound only to the 14 kD protein of European chestnut pollen extract. Two monoclonal mouse antibodies, BIP 1 and BIP 4, directed against different epitopes of Bet v I (the major birch pollen allergen), and a rabbit antibody to recombinant birch profilin (rBet v II) were used to characterize the proteins of the European chestnut pollen. The recombinant birch pollen allergens, rBet v I and rBet v II (profilin) were employed to show common allergenic structures on proteins from both birch and European chestnut pollen by IgE-inhibition experiments. Despite the fact that the 22 kD protein displayed a higher molecular weight in comparison to the 17 kD major birch pollen allergen, Bet v I, we could demonstrate reactivity of both monoclonal antibodies, BIP 1 and BIP 4, with this protein. A complete inhibiton of IgE-binding to this 22 kD protein was shown by pre-incubating sera with purified recombinant Bet v I. In addition, the 14 kD protein could be identified by IgE-inhibition studies with recombinant Bet v II and by using a rabbit anti-profilin antibody as the profilin from pollen of the European chestnut.

  13. Specific probiotics alleviate allergic rhinitis during the birch pollen season

    Institute of Scientific and Technical Information of China (English)

    Arthur C Ouwehand; Merja Nermes; Maria Carmen Collado; Nina Rautonen; Seppo Salminen; Erika Isolauri

    2009-01-01

    AIM: To investigate whether birch pollen allergy symptoms are linked with gut microbiota changes and whether probiotics have an effect on these. METHODS: Forty seven children with confirmed birch pollen allergy were randomized to receive either a probiotic combination of Lactobacillus acidophilus ( L. acidophi lus) NCFMTM (ATCC 700396) and Bifidobacterium lactis ( B. lactis) Bl-04 (ATCC SD5219) or placebo in a double-blind manner for 4 mo, starting prior to onset of the birch pollen season. Symptoms were recorded in a diary. Blood samples were taken for analysis of cytokines and eosinophils. Fecal samples were analysed for microbiota components, calprotectin and IgA. Nasal swabs were taken for analysis of eosinophils.RESULTS: The pollen season induced a reduction in Bifidobacterium, Clostridium and Bacteroides which could not be prevented by the probiotic intervention. During the intervention, significantly higher numbers 106 bacteria/g feces ( P < 0.0001) were observed in the probiotic group compared to the placebo group. During May, there was a tendency for fewer subjects,(76.2% vs 95.2%, P = 0.078) to report runny nose,while during June, fewer subjects, 11.1% vs 33.3%,reported nasal blocking in the probiotics group ( P = 0.101). Concomitantly, fewer subjects in the probiotic group had infiltration of eosinophils in the nasal mucosa compared to the placebo group, 57.1%vs 95% ( P = 0.013). Eye symptoms tended to be slightly more frequent in the probiotic group, 12.5 d [interquartile range (IQR) 6-18] vs 7.5 d (IQR 0-11.5)( P = 0.066) during May. Fecal IgA was increased in the placebo group during the pollen season; this increase was prevented by the probiotics ( P = 0.028).CONCLUSION: Birch pollen allergy was shown to be associated with changes in fecal microbiota composition. The specific combination of probiotics used was shown to prevent the pollen-induced infiltration of eosinophils into the nasal mucosa, and indicated a trend for reduced nasal symptoms.

  14. Bayesian analysis of climate change effects on observed and projected airborne levels of birch pollen

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    Zhang, Yong; Isukapalli, Sastry S.; Bielory, Leonard; Georgopoulos, Panos G.

    2013-04-01

    A Bayesian framework is presented for modeling effects of climate change on pollen indices such as annual birch pollen count, maximum daily birch pollen count, start date of birch pollen season and the date of maximum daily birch pollen count. Annual mean CO2 concentration, mean spring temperature and the corresponding pollen index of prior year were found to be statistically significant accounting for effects of climate change on four pollen indices. Results suggest that annual productions and peak values from 2020 to 2100 under different scenarios will be 1.3-8.0 and 1.1-7.3 times higher respectively than the mean values for 2000, and start and peak dates will occur around two to four weeks earlier. These results have been partly confirmed by the available historical data. As a demonstration, the emission profiles in future years were generated by incorporating the predicted pollen indices into an existing emission model.

  15. [A relationship between birch pollen counts and meteorological factors in Sapporo].

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    Shirasaki, Hideaki; Yamamoto, Tetsuo; Saikawa, Etsuko; Seki, Nobuhiko; Asakura, Kohji; Kataura, Akikatsu; Himi, Tetsuo

    2014-05-01

    Occurrence of airborne pollen in Sapporo has been studied for 19 years during the period between 1995 and 2013. There are wide year-to-year variations in the quantities of birch pollens. A simple linear regression with the least squares method was used for studying correlations between the annual quantities of birch pollens and the meteorological factors. A significant positive correlation was found between the hours of sunlight in June of the preceding year and the annual birch pollen concentrations with the correlation coefficient, R = 0.667. Also, we found the significant positive correlation between the hours of sunlight in March and the annual birch pollen concentrations with the correlation coefficient, R = 0.684. These results suggest that the atmospheric birch pollen counts can be predicted from meteorological factors.

  16. Impact of urbanization of the proteome of birch pollen and its chemotactic activity on human granulocytes

    NARCIS (Netherlands)

    Bryce, M.; Drews, O.; Schenk, M.F.; Menzel, A.; Estrella, N.; Weichenmeier, I.; Smulders, M.J.M.; Buters, J.; Ring, J.; Gorg, A.; Behrendt, H.; Traidl-Hoffmann, C.

    2010-01-01

    Background: Epidemiologic studies reveal a dramatic increase in allergies in the last decades. Air pollution is considered to be one of the factors responsible for this augmentation. The aim of this study was to analyze the impact of urbanization on birch pollen. The birch pollen proteome was invest

  17. The human eosinophil proteome. Changes induced by birch pollen allergy.

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    Woschnagg, Charlotte; Forsberg, Jens; Engström, Ake; Odreman, Federico; Venge, Per; Garcia, Rodolfo C

    2009-06-01

    Proteins from human eosinophils were separated bidimensionally and identified by mass spectrometry (336 spots/bands, 98 different proteins). Of these, 24.7% belonged to the cytoskeleton/migration group. Highly basic proteins (11.3%) were concentrated in the granule-containing cell fraction. We detected novel hyperacidic forms of cofilin-1, profilin-1 and adenylyl cyclase-associated protein, and hyperbasic forms of eosinophil-derived neurotoxin/eosinophil protein X and major basic protein homologue. We also found evidence of the triglycosylation of the heavy chain of eosinophil peroxidase. In addition, through comparative 2D image analysis, spot quantification and MS, it was found that hsc70, actin-capping protein and hyperacidic forms of eosinophil peroxidase heavy chain are overexpressed in cells from birch pollen allergic subjects, at the peak of a season. The link between these findings and an increased cellular antigen-presenting capacity and motility are discussed.

  18. Proteomic profiling of birch (Betula verrucosa) pollen extracts from different origins.

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    Erler, Anja; Hawranek, Thomas; Krückemeier, Leif; Asam, Claudia; Egger, Matthias; Ferreira, Fátima; Briza, Peter

    2011-04-01

    Pollen of the European white birch is a major source of spring pollinosis in Europe. Pollen-allergy diagnosis and treatment by specific immunotherapy commonly rely on extracts of natural origin. To gain insight into the protein content and its variability, we evaluated the profile of allergenic and non-allergenic proteins in extracts of pollen from different origins by MS-based proteomics. Aqueous extracts prepared from commercially available Swedish birch pollen, pollen collected from Austrian trees and a commercial skin prick extract were analyzed by 1-DE, 2-DE, immunoblotting and mass spectrometry, resulting in a complete inventory of extractable, disease-relevant pollen proteins. A main focus of this study was on the isoform distribution of Bet v 1, the major allergen of birch pollen. Using a combination of intact mass determination and peptide sequencing, five isoforms (a, b, d, f and j) were unequivocally identified in Swedish and Austrian birch pollen extracts, while the skin prick extract contained only isoforms a, b and d. Using the same methods as for Bet v 1, divergencies in the sequence of birch profilin (Bet v 2), a plant panallergen, were solved. The molecular characterization of pollen extracts is relevant for standardization and development of new reagents for specific immunotherapy.

  19. Daily home measurements of exhaled nitric oxide in asthmatic children during natural birch pollen exposure

    DEFF Research Database (Denmark)

    Vahlkvist, Signe; Sinding, Marianne; Skamstrup, Kirsten;

    2006-01-01

    the feasibility, repeatability, accuracy, sensitivity, and biologic plausibility of new handheld equipment for FENO measurements. We studied day-to-day home measurements of FENO during the birch pollen season in children with allergy to birch pollen and a history of mild asthma and rhinoconjunctivitis during......BACKGROUND: Fractional exhaled nitric oxide (FENO) is a sensitive marker of eosinophilic airway inflammation in asthma. Available methods have restricted measurements to the clinic, giving only a snapshot of the disease, which by nature is highly variable. OBJECTIVES: We sought to investigate...... this season, as well as in nonatopic children. METHODS: Eleven children with mild asthma and allergy to birch pollen, performed daily home measurements of FENO for 6 weeks before and during the birch pollen season by using a handheld FENO monitor (NIOX MINO). Additionally, FENO (chemiluminescence equipment...

  20. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States

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    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G.

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6 %-248 %. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  1. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States.

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6%-248%. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  2. A method to derive vegetation distribution maps for pollen dispersion models using birch as an example.

    Science.gov (United States)

    Pauling, A; Rotach, M W; Gehrig, R; Clot, B

    2012-09-01

    Detailed knowledge of the spatial distribution of sources is a crucial prerequisite for the application of pollen dispersion models such as, for example, COSMO-ART (COnsortium for Small-scale MOdeling-Aerosols and Reactive Trace gases). However, this input is not available for the allergy-relevant species such as hazel, alder, birch, grass or ragweed. Hence, plant distribution datasets need to be derived from suitable sources. We present an approach to produce such a dataset from existing sources using birch as an example. The basic idea is to construct a birch dataset using a region with good data coverage for calibration and then to extrapolate this relationship to a larger area by using land use classes. We use the Swiss forest inventory (1 km resolution) in combination with a 74-category land use dataset that covers the non-forested areas of Switzerland as well (resolution 100 m). Then we assign birch density categories of 0%, 0.1%, 0.5% and 2.5% to each of the 74 land use categories. The combination of this derived dataset with the birch distribution from the forest inventory yields a fairly accurate birch distribution encompassing entire Switzerland. The land use categories of the Global Land Cover 2000 (GLC2000; Global Land Cover 2000 database, 2003, European Commission, Joint Research Centre; resolution 1 km) are then calibrated with the Swiss dataset in order to derive a Europe-wide birch distribution dataset and aggregated onto the 7 km COSMO-ART grid. This procedure thus assumes that a certain GLC2000 land use category has the same birch density wherever it may occur in Europe. In order to reduce the strict application of this crucial assumption, the birch density distribution as obtained from the previous steps is weighted using the mean Seasonal Pollen Index (SPI; yearly sums of daily pollen concentrations). For future improvement, region-specific birch densities for the GLC2000 categories could be integrated into the mapping procedure.

  3. Glutathione-S-transferase: a minor allergen in birch pollen due to limited release from hydrated pollen.

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    Stephan Deifl

    Full Text Available Recently, a protein homologous to glutathione-S-transferases (GST was detected in prominent amounts in birch pollen by proteomic profiling. As members of the GST family are relevant allergens in mites, cockroach and fungi we investigated the allergenic relevance of GST from birch (bGST.bGST was expressed in Escherichia coli, purified and characterized by mass spectrometry. Sera from 217 birch pollen-allergic patients were tested for IgE-reactivity to bGST by ELISA. The mediator-releasing activity of bGST was analysed with IgE-loaded rat basophil leukaemia cells (RBL expressing human FcεRI. BALB/c mice were immunized with bGST or Bet v 1. Antibody and T cell responses to either protein were assessed. IgE-cross-reactivity between bGST with GST from house dust mite, Der p 8, was studied with murine and human sera in ELISA. The release kinetics of bGST and Bet v 1 from birch pollen were assessed in water, simulated lung fluid, 0.9% NaCl and PBS. Eluted proteins were quantified by ELISA and analysed by immunoblotting.Only 13% of 217 birch pollen-allergic patients showed IgE-reactivity to bGST. In RBL assays bGST induced mediator release. Immunization of mice with bGST induced specific IgE and a Th2-dominated cellular immune response comparably to immunization with Bet v 1. bGST did not cross-react with Der p 8. In contrast to Bet v 1, only low amounts of bGST were released from pollen grains upon incubation in water and the different physiological solutions.Although bGST is abundant in birch pollen, immunogenic in mice and able to induce mediator release from effector cells passively loaded with specific IgE, it is a minor allergen for birch pollen-allergic patients. We refer this discrepancy to its limited release from hydrated pollen. Hence, bGST is an example demonstrating that allergenicity depends mainly on rapid elution from airborne particles.

  4. High environmental ozone levels lead to enhanced allergenicity of birch pollen.

    Directory of Open Access Journals (Sweden)

    Isabelle Beck

    Full Text Available BACKGROUND: Evidence is compelling for a positive correlation between climate change, urbanisation and prevalence of allergic sensitisation and diseases. The reason for this association is not clear to date. Some data point to a pro-allergenic effect of anthropogenic factors on susceptible individuals. OBJECTIVES: To evaluate the impact of urbanisation and climate change on pollen allergenicity. METHODS: Catkins were sampled from birch trees from different sites across the greater area of Munich, pollen were isolated and an urbanisation index, NO2 and ozone exposure were determined. To estimate pollen allergenicity, allergen content and pollen-associated lipid mediators were measured in aqueous pollen extracts. Immune stimulatory and modulatory capacity of pollen was assessed by neutrophil migration assays and the potential of pollen to inhibit dendritic cell interleukin-12 response. In vivo allergenicity was assessed by skin prick tests. RESULTS: The study revealed ozone as a prominent environmental factor influencing the allergenicity of birch pollen. Enhanced allergenicity, as assessed in skin prick tests, was mirrored by enhanced allergen content. Beyond that, ozone induced changes in lipid composition and chemotactic and immune modulatory potential of the pollen. Higher ozone-exposed pollen was characterised by less immune modulatory but higher immune stimulatory potential. CONCLUSION: It is likely that future climate change along with increasing urbanisation will lead to rising ozone concentrations in the next decades. Our study indicates that ozone is a crucial factor leading to clinically relevant enhanced allergenicity of birch pollen. Thus, with increasing temperatures and increasing ozone levels, also symptoms of pollen allergic patients may increase further.

  5. Release of Bet v 1 from birch pollen from 5 European countries. Results from the HIALINE study

    Science.gov (United States)

    The HIALINE working Group; Buters, Jeroen T. M.; Thibaudon, Michel; Smith, Matt; Kennedy, Roy; Rantio-Lehtimäki, Auli; Albertini, Roberto; Reese, Gerald; Weber, Bernhard; Galan, Carmen; Brandao, Rui; Antunes, Celia M.; Jäger, Siegfried; Berger, Uwe; Celenk, Sevcan; Grewling, Łukasz; Jackowiak, Bogdan; Sauliene, Ingrida; Weichenmeier, Ingrid; Pusch, Gudrun; Sarioglu, Hakan; Ueffing, Marius; Behrendt, Heidrun; Prank, Marje; Sofiev, Mikhail; Cecchi, Lorenzo

    2012-08-01

    Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network).Pollen count was assessed with Hirst type pollen traps at 10 l min-1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min-1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient.Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration.Although Bet v 1 is a mixture of different

  6. Numerical simulation of birch pollen dispersion with an operational weather forecast system.

    Science.gov (United States)

    Vogel, Heike; Pauling, Andreas; Vogel, Bernhard

    2008-11-01

    We included a parameterisation of the emissions of pollen grains into the comprehensive model system COSMO-ART. In addition, a detailed density distribution of birch trees within Switzerland was derived. Based on these new developments, we carried out numerical simulations of the dispersion of pollen grains for an episode that occurred in April 2006 over Switzerland and the adjacent regions. Since COSMO-ART is based on the operational forecast model of the German Weather Service, we are presenting a feasibility study of daily pollen forecast based on methods which have been developed during the last two decades for the treatment of anthropogenic aerosol. A comparison of the model results and very detailed pollen counts documents the current possibilities and the shortcomings of the method and gives hints for necessary improvements.

  7. Prediction of the birch pollen season characteristics in Cracow, Poland using an 18-year data series.

    Science.gov (United States)

    Dorota, Myszkowska

    2013-03-01

    The aim of the study was to construct the model forecasting the birch pollen season characteristics in Cracow on the basis of an 18-year data series. The study was performed using the volumetric method (Lanzoni/Burkard trap). The 98/95 % method was used to calculate the pollen season. The Spearman's correlation test was applied to find the relationship between the meteorological parameters and pollen season characteristics. To construct the predictive model, the backward stepwise multiple regression analysis was used including the multi-collinearity of variables. The predictive models best fitted the pollen season start and end, especially models containing two independent variables. The peak concentration value was predicted with the higher prediction error. Also the accuracy of the models predicting the pollen season characteristics in 2009 was higher in comparison with 2010. Both, the multi-variable model and one-variable model for the beginning of the pollen season included air temperature during the last 10 days of February, while the multi-variable model also included humidity at the beginning of April. The models forecasting the end of the pollen season were based on temperature in March-April, while the peak day was predicted using the temperature during the last 10 days of March.

  8. Ara h 8, a Bet v 1-homologous allergen from peanut, is a major allergen in patients with combined birch pollen and peanut allergy

    NARCIS (Netherlands)

    Mittag, D.; Akkerdaas, J.; Ballmer-Weber, B.K.; Vogel, L.; Wensing, M.; Becker, W.M.; Koppelman, S.J.; Knulst, A.C.; Helbling, A.; Hefle, S.L.; Ree, R. van; Vieths, S.

    2004-01-01

    We recently described patients with soybean allergy mainly mediated by cross-reactivity to birch pollen allergens. A majority of those patients were reported to have peanut allergy. We sought to study the occurrence of peanut allergy in patients allergic to birch pollen and characterized the Bet v 1

  9. The safety and efficacy of subcutaneous birch pollen immunotherapy - a one-year, randomised, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Bødtger, U; Poulsen, Lars K.; Jacobi, H H

    2002-01-01

    There is only very limited documentation of the efficacy and safety of high-dose subcutaneous birch pollen immunotherapy (IT) in double-blind, placebo-controlled (DBPC) studies. Birch pollen is a major cause of allergic morbidity in northern Europe and in eastern parts of North America....

  10. An investigation of the possible immunological relationship between allergen extracts from birch pollen, hazelnut, potato and apple

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Løwenstein, H

    1978-01-01

    In a retrospective study on selected group of patients, the coincidence of birch pollen allergy and a clinically relevant positive prick test reaction to apples and potatoes was confirmed. Immunochemical comparison using the crossed line immunoelectrophoresis technique (CLIE) confirmed partial id...

  11. Seven different genes encode a diverse mixture of isoforms of Bet v 1, the major birch pollen allergen

    NARCIS (Netherlands)

    Schenk, M.F.; Gilissen, L.J.W.J.; Esselink, G.D.; Smulders, M.J.M.

    2006-01-01

    Background: Pollen of the European white birch (Betula pendula, syn. B. verrucosa) is an important cause of hay fever. The main allergen is Bet v 1, member of the pathogenesis-related class 10 (PR-10) multigene family. To establish the number of PR-10/Bet v 1 genes and the isoform diversity within a

  12. Purification and characterization of natural Bet v 1 from birch pollen and related allergens from carrot and celery

    NARCIS (Netherlands)

    Bollen, M.A.; Garcia, A.; Cordewener, J.H.G.; Wichers, H.J.; Helsper, J.P.F.G.; Savelkoul, H.F.J.; Boekel, van M.A.J.S.

    2007-01-01

    Birch pollen allergy is predominantly caused by the major allergen Bet v 1 and can lead to crossreactions with homologous proteins in food. Two major cross-reactive food allergens are Dau c 1 from carrot and Api g 1 from celery, which have never been purified from their natural source. Here, we desc

  13. Ligand binding modulates the structural dynamics and compactness of the major birch pollen allergen.

    Science.gov (United States)

    Grutsch, Sarina; Fuchs, Julian E; Freier, Regina; Kofler, Stefan; Bibi, Marium; Asam, Claudia; Wallner, Michael; Ferreira, Fátima; Brandstetter, Hans; Liedl, Klaus R; Tollinger, Martin

    2014-12-16

    Pathogenesis-related plant proteins of class-10 (PR-10) are essential for storage and transport of small molecules. A prominent member of the PR-10 family, the major birch pollen allergen Bet v 1, is the main cause of spring pollinosis in the temperate climate zone of the northern hemisphere. Bet v 1 binds various ligand molecules to its internal cavity, and immunologic effects of the presence of ligand have been discussed. However, the mechanism of binding has remained elusive. In this study, we show that in solution Bet v 1.0101 is conformationally heterogeneous and cannot be represented by a single structure. NMR relaxation data suggest that structural dynamics are fundamental for ligand access to the protein interior. Complex formation then leads to significant rigidification of the protein along with a compaction of its 3D structure. The data presented herein provide a structural basis for understanding the immunogenic and allergenic potential of ligand binding to Bet v 1 allergens.

  14. Prevention of birch pollen-related food allergy by mucosal treatment with multi-allergen-chimers in mice.

    Directory of Open Access Journals (Sweden)

    Elisabeth Hoflehner

    Full Text Available BACKGROUND: Among birch pollen allergic patients up to 70% develop allergic reactions to Bet v 1-homologue food allergens such as Api g 1 (celery or Dau c 1 (carrot, termed as birch pollen-related food allergy. In most cases, specific immunotherapy with birch pollen extracts does not reduce allergic symptoms to the homologue food allergens. We therefore genetically engineered a multi-allergen chimer and tested if mucosal treatment with this construct could represent a novel approach for prevention of birch pollen-related food allergy. METHODOLOGY: BALB/c mice were poly-sensitized with a mixture of Bet v 1, Api g 1 and Dau c 1 followed by a sublingual challenge with carrot, celery and birch pollen extracts. For prevention of allergy sensitization an allergen chimer composed of immunodominant T cell epitopes of Api g 1 and Dau c 1 linked to the whole Bet v 1 allergen, was intranasally applied prior to sensitization. RESULTS: Intranasal pretreatment with the allergen chimer led to significantly decreased antigen-specific IgE-dependent β-hexosaminidase release, but enhanced allergen-specific IgG2a and IgA antibodies. Accordingly, IL-4 levels in spleen cell cultures and IL-5 levels in restimulated spleen and cervical lymph node cell cultures were markedly reduced, while IFN-γ levels were increased. Immunomodulation was associated with increased IL-10, TGF-β and Foxp3 mRNA levels in NALT and Foxp3 in oral mucosal tissues. Treatment with anti-TGF-β, anti-IL10R or anti-CD25 antibodies abrogated the suppression of allergic responses induced by the chimer. CONCLUSION: Our results indicate that mucosal application of the allergen chimer led to decreased Th2 immune responses against Bet v 1 and its homologue food allergens Api g 1 and Dau c 1 by regulatory and Th1-biased immune responses. These data suggest that mucosal treatment with a multi-allergen vaccine could be a promising treatment strategy to prevent birch pollen-related food allergy.

  15. Birch pollen influence the severity of atopic eczema – prospective clinical cohort pilot study and ex vivo penetration study

    Directory of Open Access Journals (Sweden)

    Fölster-Holst R

    2015-10-01

    Full Text Available Regina Fölster-Holst,1 Jagoda Galecka,1 Sigo Weißmantel,1 Ute Dickschat,2 Frank Rippke,3 Kerstin Bohnsack,3 Thomas Werfel,4 Katja Wichmann,4 Matthias Buchner,1 Thomas Schwarz,1 Annika Vogt,5 Jürgen Lademann,5 Martina C Meinke5 1Department of Dermatology, Venerology and Allergy, University of Kiel, 2Wörth, 3Beiersdorf AG, Hamburg, 4Department of Dermatology, Venerology and Allergy, Division of Immunodermatology and Allergy Research, Hannover Medical School, Hannover, 5Department of Dermatology, Venerology and Allergology, Charité – Universitätsmedizin Berlin, Berlin, Germany Abstract: There is little clinical evidence for a correlation between the severity of atopic eczema (AE and pollen exposition. To obtain more data, we performed a clinical cohort pilot study about the influence of pollen on AE between sensitized and nonsensitized subjects and an experimental study addressing the cutaneous penetration of pollen into the skin. Fifty-five patients were monitored during birch pollen season. To study the cutaneous penetration, grass pollen allergens were applied on excised skin and the uptake in CD1c-expressing dendritic cells was investigated. The correlation between environmental pollen load and severity of the Scoring Atopic Dermatitis (SCORAD score and pruritus was observed, regardless of the status of sensitization. The sensitized group recovered significantly worse after the birch pollen season. Remarkably higher amounts of pollen allergens taken up by CD1c cells were detected in epidermal cells derived from skin explants with a disturbed epidermal barrier. These findings suggest an exacerbating role of pollen in AE utilizing the epidermal route. Keywords: aeroallergens, atopic eczema, seasonality, skin antigen-presenting cells, skin barrier penetration

  16. The major birch pollen allergen Bet v 1 induces different responses in dendritic cells of birch pollen allergic and healthy individuals.

    Directory of Open Access Journals (Sweden)

    Ursula Smole

    Full Text Available Dendritic cells play a fundamental role in shaping the immune response to allergens. The events that lead to allergic sensitization or tolerance induction during the interaction of the major birch pollen allergen Bet v 1 and dendritic cells are not very well studied. Here, we analyzed the uptake of Bet v 1 and the cross-reactive celery allergen Api g 1 by immature monocyte-derived dendritic cells (iMoDCs of allergic and normal donors. In addition, we characterized the allergen-triggered intracellular signaling and transcriptional events. Uptake kinetics, competitive binding, and internalization pathways of labeled allergens by iMoDCs were visualized by live-cell imaging. Surface-bound IgE was detected by immunofluorescence microscopy and flow cytometry. Allergen- and IgE-induced gene expression of early growth response genes and Th1 and Th2 related cytokines and chemokines were analyzed by real-time PCR. Phosporylation of signaling kinases was analyzed by Western blot. Internalization of Bet v 1 by iMoDCs of both donor groups, likely by receptor-mediated caveolar endocytosis, followed similar kinetics. Bet v 1 outcompeted Api g 1 in cell surface binding and uptake. MoDCs of allergic and healthy donors displayed surface-bound IgE and showed a pronounced upregulation of Th2 cytokine- and NFκB-dependent genes upon non-specific Fcε receptor cross-linking. In contrast to these IgE-mediated responses, Bet v 1-stimulation increased transcript levels of the Th2 cytokines IL-4 and IL-13 but not of NFκB-related genes in MoDCs of BP allergic donors. Cells of healthy donors were either unresponsive or showed elevated mRNA levels of Th1-promoting chemokines. Moreover, Bet v 1 was able to induce Erk1/2 and p38 MAPK activation in BP allergics but only a slight p38 activation in normal donors. In conclusion, our data indicate that Bet v 1 favors the activation of a Th2 program only in DCs of BP allergic individuals.

  17. Ligand Binding Modulates the Structural Dynamics and Compactness of the Major Birch Pollen Allergen

    Science.gov (United States)

    Grutsch, Sarina; Fuchs, Julian E.; Freier, Regina; Kofler, Stefan; Bibi, Marium; Asam, Claudia; Wallner, Michael; Ferreira, Fátima; Brandstetter, Hans; Liedl, Klaus R.; Tollinger, Martin

    2014-01-01

    Pathogenesis-related plant proteins of class-10 (PR-10) are essential for storage and transport of small molecules. A prominent member of the PR-10 family, the major birch pollen allergen Bet v 1, is the main cause of spring pollinosis in the temperate climate zone of the northern hemisphere. Bet v 1 binds various ligand molecules to its internal cavity, and immunologic effects of the presence of ligand have been discussed. However, the mechanism of binding has remained elusive. In this study, we show that in solution Bet v 1.0101 is conformationally heterogeneous and cannot be represented by a single structure. NMR relaxation data suggest that structural dynamics are fundamental for ligand access to the protein interior. Complex formation then leads to significant rigidification of the protein along with a compaction of its 3D structure. The data presented herein provide a structural basis for understanding the immunogenic and allergenic potential of ligand binding to Bet v 1 allergens. PMID:25517162

  18. Changes in expression of BetV1 allergen of silver birch pollen in urbanized area of Ukraine.

    Science.gov (United States)

    Žiarovská, Jana; Labajová, Mária; Ražná, Katarína; Bežo, Milan; Štefúnová, Veronika; Shevtsova, Tatiana; Garkava, Kateryna; Brindza, Ján

    2013-01-01

    The aim of the study was to determinate the level of expression of silver birch allergen Betv1 in pollen samples from different Ukraine areas by RT-qPCR SYBR Green assay. Protocol for quantifying the expression of Betv1 allergen was developed when testing of three housekeeping genes-cyclophylin, alpha-tubulin and transcription factor CBF1. Samples from urbanized area was analysed by real-time PCR when a sample from forest growth conditions was used as a calibrator. Real-time PCR based quantifying of Betv1 provides a useful method for rapid and sensitive analyses of this silver birch allergen. Our results show higher expression levels in samples from central parts of urbanized area as housing estates when compared to the samples from borders of the urbanized area.

  19. Seven different genes encode a diverse mixture of isoforms of Bet v 1, the major birch pollen allergen

    Directory of Open Access Journals (Sweden)

    Gilissen Ludovicus JWJ

    2006-07-01

    Full Text Available Abstract Background Pollen of the European white birch (Betula pendula, syn. B. verrucosa is an important cause of hay fever. The main allergen is Bet v 1, member of the pathogenesis-related class 10 (PR-10 multigene family. To establish the number of PR-10/Bet v 1 genes and the isoform diversity within a single tree, PCR amplification, cloning and sequencing of PR-10 genes was performed on two diploid B. pendula cultivars and one interspecific tetraploid Betula hybrid. Sequences were attributed to putative genes based on sequence identity and intron length. Information on transcription was derived by comparison with homologous cDNA sequences available in GenBank/EMBL/DDJB. PCR-cloning of multigene families is accompanied by a high risk for the occurrence of PCR recombination artifacts. We screened for and excluded these artifacts, and also detected putative artifact sequences among database sequences. Results Forty-four different PR-10 sequences were recovered from B. pendula and assigned to thirteen putative genes. Sequence homology suggests that three genes were transcribed in somatic tissue and seven genes in pollen. The transcription of three other genes remains unknown. In total, fourteen different Bet v 1-type isoforms were identified in the three cultivars, of which nine isoforms were entirely new. Isoforms with high and low IgE-reactivity are encoded by different genes and one birch pollen grain has the genetic background to produce a mixture of isoforms with varying IgE-reactivity. Allergen diversity is even higher in the interspecific tetraploid hybrid, consistent with the presence of two genomes. Conclusion Isoforms of the major birch allergen Bet v 1 are encoded by multiple genes, and we propose to name them accordingly. The present characterization of the Bet v 1 genes provides a framework for the screening of specific Bet v 1 genes among other B. pendula cultivars or Betula species, and for future breeding for trees with a reduced

  20. A non-allergenic Ole e 1-like protein from birch pollen as a tool to design hypoallergenic vaccine candidates.

    Science.gov (United States)

    Marazuela, Eva G; Hajek, Roswitha; Villalba, Mayte; Barber, Domingo; Breiteneder, Heimo; Rodríguez, Rosalía; Batanero, Eva

    2012-02-01

    Recombinant DNA technology offers several approaches to convert allergens into hypoallergenic derivatives that can represent the basis of novel, safer and more effective forms of allergy vaccines. In this context, we used a new strategy for the design of a hypoallergenic derivative of Ole e 1, the main allergen of olive pollen. By screening a cDNA library from birch pollen, the clone BB18, encoding the birch counterpart of Ole e 1, was identified. In this study, BB18 has been produce in Pichia pastoris as a recombinant protein and immunologically characterized. The well-established non-allergenic properties of BB18 were used to generate a genetic variant of Ole e 1, named OB(55-58), by site-direct mutagenesis of four residues (E(55)V(56)G(57)Y(58)) in an IgE/IgG epitope of Ole e 1 by the corresponding ones in BB18 (SDSE). OB(55-58) was expressed in P. pastoris, purified to homogeneity and analyzed for IgE-reactivity by means of ELISA using sera from olive pollen allergic patients and rat basophil activation assay. T cell reactivity was assayed in a mouse model of Ole e 1 sensitization. The mutant OB(55-58) exhibited an impaired IgE reactivity, but not affected T cell reactivity, compared to wild type rOle e 1. This study emphasizes the usefulness of BB18 as a tool for epitope mapping and for engineering hypoallergenic derivatives of Ole e 1 as vaccine candidates for allergy prevention and treatment.

  1. Protein-lipid composition of silver birch (Betula verrucosa pollen and its antioxidant activity depending on habitat

    Directory of Open Access Journals (Sweden)

    T. Shevtsova

    2013-12-01

    Full Text Available Pollen has various effects on the human body. In order to study and compare the biological activity of the mature pollen grains of Betula verrucosa Ehrh. we investigated the protein-lipid composition and total antioxidant activity (TAA of 10 samples from different habitats in the territory of Ukraine and the Slovak Republic. The collection sites are near highways and apartment blocks, as well as a nature reserve, forest and botanical garden. The protein content was determined by the Kjeldahl method. A chromatographic analysis of fatty acids from lipids was performed using a “Cvet 500” gas chromatograph, equipped with a flame-ionization detector in the isothermal mode. The bioactivity of aqueous, ethanol and methanol extracts of pollen grains was evaluated by the DPPH free radical scavenging method (2,2-diphenyl-1-picrylhydrazyl by means spectrophotometry in vitro. The protein content of the pollen of B. verrucosa ranged from 17.9% to 25.6%, depending on the habitat. Unsaturated fatty acids were found in higher amounts than saturated fatty acids. The profile of fatty acids indicates a higher content of palmitic (33.9%, oleic (29.5% and linoleic (27.8% acids and a low content of arachidonic (0.4% and pentadecanoic (0.8% acids. We also established that silver birch pollen is characterized by high antioxidant activity. The measured value of TAA for aqueous pollen extracts was within 74.8–85.5%. For the ethanol extracts it was quantified within 60.3–95.0% and for the methanol extracts – 46.1–92.6%. The Tukey test was used to determine the differences between the means at a level of P < 0.05. A strong correlation coefficient (0.70 was defined between the protein content and the TAA of aqueous extracts. In general, the Ukrainian and Slovak samples of pollen differ in the fatty acid composition of lipids and aqueous and ethanol TAA extracts. Pollen of B. verrucosa should be used for diagnostic, therapeutic and prophylactic purposes as close

  2. Genetic engineering of trimers of hypoallergenic fragments of the major birch pollen allergen, Bet v 1, for allergy vaccination.

    Science.gov (United States)

    Vrtala, Susanne; Fohr, Monika; Campana, Raffaela; Baumgartner, Christian; Valent, Peter; Valenta, Rudolf

    2011-03-01

    An immunotherapy trial performed in allergic patients with hypoallergenic recombinant fragments, comprising aa 1-74 and 75-160 of the major birch pollen allergen, Bet v 1, has indicated that the induction of allergen-specific IgG responses may be an important mechanism of this treatment. To investigate whether the immunogenicity of the rBet v 1 fragments can be increased, recombinant trimers of the fragments were produced. For this purpose, DNA trimers of rBet v 1 aa 1-74 as well as of rBet v 1 aa 75-160 were subcloned into expression plasmid pET 17b, expressed in Escherichia coli and purified. The fragments as well as the fragment trimers showed a reduced IgE-binding capacity and allergenic activity compared to rBet v 1 wildtype when tested in allergic patients. Both rBet v 1 aa 75-160 monomer and trimer induced high titers of allergen-specific IgG1 Abs in mice. Interestingly, rBet v 1 aa 1-74 trimer induced a much higher IgG(1) response to rBet v 1 than rBet v 1 aa 1-74 monomer. Consequently, IgG Abs induced with the rBet v 1 aa 1-74 trimer inhibited birch pollen allergic patients' IgE-binding 10-fold more efficiently than IgG Abs induced with the monomer. Our data show that the immunogenicity of allergy vaccines can be increased by oligomerization.

  3. The impact of nitration on the structure and immunogenicity of the major birch pollen allergen Bet v 1.0101.

    Science.gov (United States)

    Ackaert, Chloé; Kofler, Stefan; Horejs-Hoeck, Jutta; Zulehner, Nora; Asam, Claudia; von Grafenstein, Susanne; Fuchs, Julian E; Briza, Peter; Liedl, Klaus R; Bohle, Barbara; Ferreira, Fátima; Brandstetter, Hans; Oostingh, Gertie J; Duschl, Albert

    2014-01-01

    Allergy prevalence has increased in industrialized countries. One contributing factor could be pollution, which can cause nitration of allergens exogenously (in the air) or endogenously (in inflamed lung tissue). We investigated the impact of nitration on both the structural and immunological behavior of the major birch pollen allergen Bet v 1.0101 to determine whether nitration might be a factor in the increased incidence of allergy. Bet v 1.0101 was nitrated with tetranitromethane. Immune effects were assessed by measuring the proliferation of specific T-cell lines (TCLs) upon stimulation with different concentrations of nitrated and unmodified allergen, and by measurement of cytokine release of monocyte-derived dendritic cells (moDCs) and primary DCs (primDCs) stimulated with nitrated versus unmodified allergen. HPLC-MS, crystallography, gel electrophoresis, amino acid analysis, size exclusion chromatography and molecular dynamics simulation were performed to characterize structural changes after nitration of the allergen. The proliferation of specific TCLs was higher upon stimulation with the nitrated allergen in comparison to the unmodified allergen. An important structural consequence of nitration was oligomerization. Moreover, analysis of the crystal structure of nitrated Bet v 1.0101 showed that amino acid residue Y83, located in the hydrophobic cavity, was nitrated to 100%. Both moDCs and primDCs showed decreased production of TH1-priming cytokines, thus favoring a TH2 response. These results implicate that nitration of Bet v 1.0101 might be a contributing factor to the observed increase in birch pollen allergy, and emphasize the importance of protein modifications in understanding the molecular basis of allergenicity.

  4. The impact of nitration on the structure and immunogenicity of the major birch pollen allergen Bet v 1.0101.

    Directory of Open Access Journals (Sweden)

    Chloé Ackaert

    Full Text Available Allergy prevalence has increased in industrialized countries. One contributing factor could be pollution, which can cause nitration of allergens exogenously (in the air or endogenously (in inflamed lung tissue. We investigated the impact of nitration on both the structural and immunological behavior of the major birch pollen allergen Bet v 1.0101 to determine whether nitration might be a factor in the increased incidence of allergy. Bet v 1.0101 was nitrated with tetranitromethane. Immune effects were assessed by measuring the proliferation of specific T-cell lines (TCLs upon stimulation with different concentrations of nitrated and unmodified allergen, and by measurement of cytokine release of monocyte-derived dendritic cells (moDCs and primary DCs (primDCs stimulated with nitrated versus unmodified allergen. HPLC-MS, crystallography, gel electrophoresis, amino acid analysis, size exclusion chromatography and molecular dynamics simulation were performed to characterize structural changes after nitration of the allergen. The proliferation of specific TCLs was higher upon stimulation with the nitrated allergen in comparison to the unmodified allergen. An important structural consequence of nitration was oligomerization. Moreover, analysis of the crystal structure of nitrated Bet v 1.0101 showed that amino acid residue Y83, located in the hydrophobic cavity, was nitrated to 100%. Both moDCs and primDCs showed decreased production of TH1-priming cytokines, thus favoring a TH2 response. These results implicate that nitration of Bet v 1.0101 might be a contributing factor to the observed increase in birch pollen allergy, and emphasize the importance of protein modifications in understanding the molecular basis of allergenicity.

  5. Oocyst-Derived Extract of Toxoplasma Gondii Serves as Potent Immunomodulator in a Mouse Model of Birch Pollen Allergy.

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    Angelika Wagner

    Full Text Available Previously, we have shown that oral infection with Toxoplasma gondii oocysts prevented type I allergy in mice. Here we investigated whether the application of a T. gondii oocyst lysate antigen (OLA could also reduce allergy development. BALB/c mice were immunised twice with OLA followed by sensitisation with the major birch pollen (BP allergen Bet v 1 and an aerosol challenge with BP extract.First, we tested OLA in vitro. Stimulation of splenocytes and bone marrow-derived dendritic cells (BMDC with OLA led to the production of pro-inflammatory and regulatory cytokines such as IL-6, IFN-γ and IL-10. Moreover, BMDC exposed to OLA upregulated the maturation markers CD40, CD80, CD86, and MHCII. Furthermore, OLA was recognised by TLR2-transfected human embryonic kidney cells.Immunisation of mice with OLA induced high levels of Toxoplasma-specific IgG antibodies in sera along with increased production of IFN-γ and IL-10 in Toxoplasma-antigen restimulated splenocytes. OLA reduced allergic airway inflammation as manifested by significant reduction of eosinophils in bronchoalveolar fluids, decreased cellular infiltrates and mucus production in the lungs. Accordingly, Bet v 1-specific IgE was decreased in OLA-pretreated mice. The reduced allergic immune responses were accompanied by increased numbers of CD4+CD25highFoxp3+ regulatory T cells in spleens as well as by increased numbers of granulocytic myeloid-derived suppressor cells in lungs when compared to sensitised controls suggesting that these two cell populations might be involved in the suppression of the allergic immune responses.Our data demonstrate that pretreatment with the oocyst extract can exert anti-allergic effects comparable to T. gondii infection. Thus, the immunomodulatory properties of the parasite extract indicate that this extract and in the future defined molecules thereof might serve as immunomodulatory adjuvants in allergy treatment and prophylaxis.

  6. The seasonal symptoms of hyposensitized and untreated hay fever patients in relation to birch pollen counts: correlations with nasal sensitivity, prick tests and RAST.

    Science.gov (United States)

    Viander, M; Koivikko, A

    1978-07-01

    A 2 year prospective study of thirty-eight birch pollen-sensitive hay fever patients under specific immunotherapy and of nineteen untreated control patients showed a significant correlation between the total seasonal symptom scores of the patients and their clinical sensitivities assessed by the RAST and a graded nasal test. The agreement between a positive nasal test and a positive RAST was 74%. In the early season with low pollen counts the onset of symptoms was significantly associated with high sensitivity of the patients, while many patients showed symptoms in the late season irrespective of their nasal and RAST sensitivity. About 90% of both the treated and the untreated patients reported mild symptoms when the pollen count exceeded 80/m(3) in the early season. 80% of them still had symptoms when the count was below 30/m(3) in the late pollen season. Although hyposensitization therapy had no effect on the occurrence of the mild symptoms, the treated patinets had severe symptoms significantly less often than the untreated ones on days with high pollen counts.

  7. A randomized DBPC trial to determine the optimal effective and safe dose of a SLIT-birch pollen extract for the treatment of allergic rhinitis : results of a phase II study

    NARCIS (Netherlands)

    Pfaar, O.; van Twuijver, E.; Boot, J. D.; Opstelten, D. J. E.; Klimek, L.; van Ree, R.; Diamant, Z.; Kuna, P.; Panzner, P.

    2016-01-01

    Background: Sublingual immunotherapy (SLIT) is a potential efficacious and safe treatment option for patients with respiratory, IgE-mediated allergic diseases. A combined tolerability, dose-finding study with a sublingual liquid birch pollen preparation (SB) was conducted. Methods: Two hundred and s

  8. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe;

    2003-01-01

    Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch...

  9. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe;

    2003-01-01

    Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch.......001). These results show that high avidity IgG of low inter-individual difference in Bet v 1 binding quality is the dominant binding factor of Bet v 1 in sera of birch pollen-allergic patients, and that SAV-induced inhibition of binding of Bet v 1 to IgE can be explained mainly or solely by increased amounts of IgG....

  10. Crossed radio-immunoisoelectric focusing as a method of identifying isoallergens: identification of isoallergens in rat urine extracts

    Energy Technology Data Exchange (ETDEWEB)

    Longbottom, J.L. (Cardiothoracic Institute, London (UK). Dept. of Allergy and Clinical Immunology)

    1984-03-30

    A method of 2-dimensional radio-immunoelectrophoresis to detect directly the presence of 'isoallergens' in complex allergenic (skin test) extracts is described. This procedure, in which the components are separated by isoelectric focusing in agarose gel in the first dimension is therefore basically similar to that of crossed radio-immunoelectrophoresis, and hence has been termed crossed radio-immunoisoelectric focusing. The method has been applied to the allergens present in rat urine and has verified the presence of the cross-reacting ..cap alpha../sub 2/-euglobulin and prealbumin components in (at least) 3 and 2 isoallergenic forms respectively.

  11. Crystallographically mapped ligand binding differs in high and low IgE binding isoforms of birch pollen allergen bet v 1.

    Science.gov (United States)

    Kofler, Stefan; Asam, Claudia; Eckhard, Ulrich; Wallner, Michael; Ferreira, Fátima; Brandstetter, Hans

    2012-09-07

    The ability of pathogenesis-related proteins of family 10 to bind a broad spectrum of ligands is considered to play a key role for their physiological and pathological functions. In particular, Bet v 1, an archetypical allergen from birch pollen, is described as a highly promiscuous ligand acceptor. However, the detailed recognition mechanisms, including specificity factors discriminating binding properties of naturally occurring Bet v 1 variants, are poorly understood. Here, we report crystal structures of Bet v 1 variants in complex with an array of ligands at a resolution of up to 1.2 Å. Residue 30 within the hydrophobic pocket not only discriminates in high and low IgE binding Bet v 1 isoforms but also induces a drastic change in the binding mode of the model ligand deoxycholate. Ternary crystal structure complexes of Bet v 1 with several ligands together with the fluorogenic reporter 1-anilino-8-naphthalene sulfonate explain anomalous fluorescence binding curves obtained from 1-anilino-8-naphthalene sulfonate displacement assays. The structures reveal key interaction residues such as Tyr83 and rationalize both the binding specificity and promiscuity of the so-called hydrophobic pocket in Bet v 1. The intermolecular interactions of Bet v 1 reveal an unexpected complexity that will be indispensable to fully understand its roles within the physiological and allergenic context.

  12. Allergic asthmatics show divergent lipid mediator profiles from healthy controls both at baseline and following birch pollen provocation.

    Directory of Open Access Journals (Sweden)

    Susanna L Lundström

    Full Text Available BACKGROUND: Asthma is a respiratory tract disorder characterized by airway hyper-reactivity and chronic inflammation. Allergic asthma is associated with the production of allergen-specific IgE and expansion of allergen-specific T-cell populations. Progression of allergic inflammation is driven by T-helper type 2 (Th2 mediators and is associated with alterations in the levels of lipid mediators. OBJECTIVES: Responses of the respiratory system to birch allergen provocation in allergic asthmatics were investigated. Eicosanoids and other oxylipins were quantified in the bronchoalveolar lumen to provide a measure of shifts in lipid mediators associated with allergen challenge in allergic asthmatics. METHODS: Eighty-seven lipid mediators representing the cyclooxygenase (COX, lipoxygenase (LOX and cytochrome P450 (CYP metabolic pathways were screened via LC-MS/MS following off-line extraction of bronchoalveolar lavage fluid (BALF. Multivariate statistics using OPLS were employed to interrogate acquired oxylipin data in combination with immunological markers. RESULTS: Thirty-two oxylipins were quantified, with baseline asthmatics possessing a different oxylipin profile relative to healthy individuals that became more distinct following allergen provocation. The most prominent differences included 15-LOX-derived ω-3 and ω-6 oxylipins. Shared-and-Unique-Structures (SUS-plot modeling showed a correlation (R(2 = 0.7 between OPLS models for baseline asthmatics (R(2Y[cum] = 0.87, Q(2[cum] = 0.51 and allergen-provoked asthmatics (R(2Y[cum] = 0.95, Q(2[cum] = 0.73, with the majority of quantified lipid mediators and cytokines contributing equally to both groups. Unique structures for allergen provocation included leukotrienes (LTB(4 and 6-trans-LTB(4, CYP-derivatives of linoleic acid (epoxides/diols, and IL-10. CONCLUSIONS: Differences in asthmatic relative to healthy profiles suggest a role for 15-LOX products of both ω-6 and ω-3 origin in allergic

  13. [Oral allergy syndrome among patients with birch pollinosis in Sapporo].

    Science.gov (United States)

    Yamamoto, Tetsuo; Asakura, Kohji; Shirasaki, Hideaki; Himi, Tetsuo; Ogasawara, Hideki; Narita, Shin-Ichirou; Kataura, Akikatsu

    2004-04-01

    We evaluated the relationships between oral and pharyngeal hypersensitivity to fruits and vegetables (oral allergy syndrome) and birch pollinosis in 2003 in Sapporo. 1. Of 153 patients with birch pollinosis (seasonal nasal or ocular symptom and CAP positive [birch pollen CAP score 2 or more]), 65 patients (42%) have episode of oral allergy syndrome (OAS). And that rate in 2003 was higher than in 1992 and was equal to in 1998. 2. Among birch pollinosis patients, the higher the CAP score of birch pollen, the higher the prevalences of OAS were found to be. 3. Among birch pollinosis patients, female have OAS much more than male. 4. Among birch pollinosis patients in 1998, patients who visited to ENT clinic for medical consultation of birch pollinosis in March and April have OAS much more than patients who visited in May and June.

  14. Pollen

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past vegetation and climate derived from pollen found in lake and ocean sediments. Parameter keywords describe what was measured in this data set....

  15. Vaccination for birch pollen allergy

    DEFF Research Database (Denmark)

    Jakobsen, C G; Bodtger, U; Poulsen, Lars K.

    2005-01-01

    Allergen-specific immunotherapy (SIT) is associated with increased levels of allergen-specific IgG in serum. However, it is not clear to what extent qualitative changes in the allergen binding capacity of IgG may be induced as well....

  16. 桦树花粉、大豆和苹果过敏原之间高免疫球蛋白E 相关性表明中国北方地区桦树花粉过敏患者很可能同时患有花粉-食物综合征%High correlation of specific IgE sensitization between birch pollen, soy and apple allergens indicates pollen-food allergy syndrome among birch pollen allergic patients in northern China

    Institute of Scientific and Technical Information of China (English)

    Guo-dong HAO; Yi-wu ZHENG; Zhi-xiang WANG; Xing-ai KONG; Zhi-jing SONG; Xu-xin LAI; Michael D SPANGFORT

    2016-01-01

    目的:研究中国北方地区桦树花粉过敏及花粉–食物过敏综合征。  创新点:国内首次研究花粉–食物过敏综合征,为中国北方地区此类患者的诊断和治疗提出了新思路。  方法:采集临床中过敏患者血清,检测桦树花粉及其主要过敏原特异性免疫球蛋白 E(IgE),同时检测大豆和苹果过敏原的特异性IgE,并评价其相关性。  结论:中国北方地区桦树花粉季节对此花粉过敏的患者有16.7%以上,主要是对桦树花粉第一组过敏原致敏。这些患者大多数同时对大豆和苹果的主要过敏原过敏,这种特异性IgE高相关性说明临床上存在花粉–食物过敏综合征。%Background: Birch pollen sensitization and associated pol en-food syndrome among Chinese al ergic patients have not been investigated. Methods: Sera from 203 al ergic patients from the northern part of China and col ected during February to July 2014 were investigated. Specific immunoglobulin E (IgE) against birch pol en extract Bet v and major birch pollen allergen Bet v 1 were measured using the ADVIA Centaur. The presence of major apple al ergen Mal d 1 and soy bean al ergen Gly m 4 specific IgE was measured by ImmunoCAP 100. Results:Among the 203 sera, 34 sera (16.7%) had specific IgE to Bet v and of these, 28 sera (82.4%) contained Bet v 1-specific IgE. Among the 28 sera with Bet v 1-specific IgE, 27 sera (96.4%) contained Mal d 1-specific IgE and 22 sera (78.6%) contained Gly m 4-specific IgE. Of the 34 Bet v-positive sera, 6 sera (17.6%) contained no specific IgE for Bet v 1, Mal d 1, or Gly m 4. Almost al Bet v-positive sera were donated during the birch pollen season. Conclusions:The prevalence of birch al ergy among patients visiting health care during pol en season can be as high as 16.7%in Tangshan City. The majority of Chinese birch al ergic patients are IgE-sensitized to the major birch pol en al ergen Bet v 1 as wel as to the

  17. Footprint areas of pollen from alder (Alnus and birch (Betula in the UK (Worcester and Poland (Wrocław during 2005–2014

    Directory of Open Access Journals (Sweden)

    Carsten Ambelas Skjøth

    2015-12-01

    Full Text Available In this study we analyzed daily pollen concentrations of Alnus spp. and Betula spp. from Worcester, UK and Wrocław, Poland. We analyzed seasonality, annual pollen index and footprint areas for the observed pollen concentrations by using the trajectory model hybrid single particle Lagrangian integrated trajectory (HYSPLIT. We examined 10 years of data during the period 2005–2014 and found substantial differences in the seasonality, pollen indices and footprint areas. For both genera, concentrations in Wrocław are in general much higher, the seasons are shorter and therefore more intense than in Worcester. The reasons appear to be related to the differences in overall climate between the two sites and more abundant sources in Poland than in England. The footprint areas suggest that the source of the pollen grains are mainly local trees but appear to be augmented by remote sources, in particular for Betula spp. but only to a small degree for Alnus spp. For Betula spp., both sites appear to get contributions from areas in Germany, the Netherlands and Belgium, while known Betula spp. rich regions in Russia, Belarus and Scandinavia had a very limited impact on the pollen concentrations in Worcester and Wrocław. Substantial and systematic variations in pollen indices are seen for Betula spp. in Wrocław with high values every second year while a similar pattern is not observed for Worcester. This pattern was not reproduced for Alnus spp.

  18. A case of birch pollen-related food allergy syndrome%桦树花粉相关的食物过敏综合征一例

    Institute of Scientific and Technical Information of China (English)

    邵洁; 罗海燕; A Purohit; G Pauli

    2005-01-01

    70%以上桦树花粉过敏患者同时存在对某些植物源性食物过敏,即所谓的花粉相关的食物过敏(pollen related food allergy)。我们报道1例典型的桦树花粉过敏,随后发展成为对一些植物性食物过敏,并产生显著的临床症状,籍此阐明桦树花粉相关的食物过敏的临床和免疫学特征。

  19. The importance of the stationary and individual pollen monitoring for the diagnostic of pollen allergy

    Directory of Open Access Journals (Sweden)

    Dorota Myszkowska

    2012-12-01

    Full Text Available The aim of the study was to evaluate pollen seasons of selected taxa with particular reference to allergic taxa such as birch (Betula sp., grasses (Poaceae, mugwort (Artemisia sp. in Cracow in 2003 and 2004 (project number 3 PO5D 034 24 funded by the State Committee for Scientific Research. Pollen concentrations obtained using the stationary Burkard trap and personal Partrap FA 52 were compared. The volumetric method was used in the study. Average daily concentrations (pollen grains × m-3 were obtained by counting pollen grains every hour along 4 longitudinal transects and applying an appropriate conversion factor. Duration of the pollen season was determined using the 95% method. Variations in annual totals of pollen grains (birch and mugwort, in start dates (especially for grasses and in the season duration (birch and grasses were found. The comparison of pollen concentrations obtained using the stationary and personal traps at the same place showed non statistically significant correlation for all the studied taxa and statistically significant correlations for birch, mugwort and grasses (Spearman rank correlation. However, the statistically significant differences between the concentrations obtained using Burkard and Partrap carried by patients (Wilcoxon's test were noted. Very low concentrations of pollen grains measured indoor (work, flats and the influence of the local plants growing in separate place (courtyard of the Allergology Department on the pollen concentration were found.

  20. Lipid transfer protein-linked hazelnut allergy in children from a non-Mediterranean birch-endemic area

    NARCIS (Netherlands)

    Flinterman, Annebeth E.; Akkerdaas, Jaap H.; Jager, Constance F. den Hartog; Rigby, Neil M.; Fernandez-Rivas, Montserrat; Hoekstra, Maarten O.; Bruijnzeel-Koomen, Carla A.; Knuist, Andr C.; van Ree, Ronald; Pasmans, Suzanne G.

    2008-01-01

    Background: Hazelnut allergy in birch pollen-exposed areas is usually due to cross-reactivity (Cor a 1 and 2) and is usually mild in nature (oral allergy). In areas without birches, severe reactions are more prevalent and linked to sensitization to the lipid transfer protein (LTP) Cor a 8. Objective

  1. Properties of tree and grass pollen allergens: reinvestigation of the linkage between solubility and allergenicity.

    Science.gov (United States)

    Vrtala, S; Grote, M; Duchêne, M; van Ree, R; Kraft, D; Scheiner, O; Valenta, R

    1993-01-01

    In this study we reinvestigated the kinetics of allergen release from birch pollen (Betula verrucosa) and timothy grass pollen (Phleum pratense) using different protein extraction procedures, immunoblotting with specific antibodies and immune electron microscopy. Pollen allergens such as the major birch pollen allergen, Bet v I, the major timothy grass pollen allergens, Phl p I and Phl p V, group-II/III allergens from timothy grass and profilins were released rapidly and in large amounts from hydrated pollen. Within a few minutes pollen allergens could be detected in aqueous supernatants prepared from birch and grass pollen with serum IgE or specific antibodies. In parallel the allergen content in the pollen pellet fractions decreased. A nonallergenic protein such as heat shock protein 70 can be extracted in sufficient amounts only with harsh extraction procedures. Immune electron microscopy of dry and rehydrated birch pollens showed that after short hydration, the major birch pollen allergen, Bet v I, migrated into the exine and to the surface of intact pollen grains, whereas profilin, against which a lower percentage of patients is sensitized, was retained in the pollen grain. Comparing the amino acid composition and hydrophilicity of the tested allergens with a nonallergenic protein such as heat shock protein 70, no significant difference was noted. In agreement with earlier observations we conclude that the allergenic properties of proteins are rather linked to the amount and speed of solubility from airborne particles than to intrinsic properties.

  2. Winter Birch Trees

    Science.gov (United States)

    Sweeney, Debra; Rounds, Judy

    2011-01-01

    Trees are great inspiration for artists. Many art teachers find themselves inspired and maybe somewhat obsessed with the natural beauty and elegance of the lofty tree, and how it changes through the seasons. One such tree that grows in several regions and always looks magnificent, regardless of the time of year, is the birch. In this article, the…

  3. [Pollen as the cause of allergies].

    Science.gov (United States)

    Schmid-Grendelmeier, P

    2001-05-01

    Pollinosis or hay fever is the most common allergic disease in Switzerland. For symptoms during spring pollens of birch and related trees (alder, hazel) and also ash tree are responsible, while hay fever during summer is mainly caused by pollens of grasses, rye and mugwort. These main plant pollen allergens, relevant cross-reactivities with other pollen and food allergens are reviewed in this article. The well-established methods of pollen-counting in Switzerland allow to define the varying amounts of measurable pollen depending on geographic and climatic conditions. Similarly clinical symptoms, the diagnostic work-up of pollen allergies and therapeutic aspects including preventive measures, symptomatic therapy and specific immunotherapy are presented. Finally, occupational and travelling aspects of pollinosis are briefly discussed.

  4. Ash pollen allergy: reliable detection of sensitization on the basis of IgE to Ole e 1.

    Science.gov (United States)

    Imhof, Konrad; Probst, Elisabeth; Seifert, Burkhardt; Regenass, Stephan; Schmid-Grendelmeier, Peter

    Background: Alongside hazel, alder and birch pollen allergies, ash pollen allergy is a relevant cause of hay fever during spring in the European region. For some considerable time, ash pollen allergy was not routinely investigated and its clinical relevance may well have been underestimated, particularly since ash and birch tree pollination times are largely the same. Ash pollen extracts are not yet well standardized and diagnosis is therefore sometimes unreliable. Olive pollen, on the other hand, is strongly cross-reactive with ash pollen and is apparently better standardized. Therefore, the main allergen of olive pollen, Ole e 1, has been postulated as a reliable alternative for the detection of ash pollen sensitization. Methods: To determine to what extent specific IgE against Ole e 1 in patients with ash pollen allergy is relevant, we included 183 subjects with ash pollen allergy displaying typical symptoms in March/April and positive skin prick test specific IgE against Ole e 1 (t224) and ash pollen (t25) and various birch allergens (Bet v 1, Bet v 2/v 4) in a retrospective study. Results: A significant correlation was seen between specific IgE against Ole e 1 and ash pollen, but also to a slightly lesser extent between IgE against Ole e 1 and skin prick test with ash pollen, the latter being even higher than IgE and skin prick test both with ash pollen. No relevant correlation was found with birch pollen allergens, demonstrating the very limited cross-reactivity between ash and birch pollen. Conclusion: It appears appropriate to determine specific IgE against Ole e 1 instead of IgE against ash pollen to detect persons with ash pollen allergy. Our findings may also support the idea of using possibly better standardized or more widely available olive pollen extracts instead of ash pollen extract for allergen-specific immunotherapy.

  5. The effect of meteorological factors on airborne Betula pollen concentrations in Lublin (Poland).

    Science.gov (United States)

    Piotrowska, Krystyna; Kubik-Komar, Agnieszka

    2012-12-01

    The present study investigated the pattern of the birch atmospheric pollen seasons in Lublin in the period 2001-2010. Pollen monitoring was conducted using a Lanzoni VPPS 2000 sampler. The atmospheric pollen seasons were determined with the 98% method. Regression analysis was used to determine correlations between meteorological conditions and the pattern of the birch pollen season. On average, the birch pollen season started on 12 April, ended on 13 May, and lasted 32 days. The peak value and the Seasonal Pollen Index showed the greatest variation in particular years. All the seasons were right-skewed. During the study years, a trend was found towards earlier occurrence of the seasonal peak. Regression equations were developed for the following parameters of the atmospheric pollen season: start, duration, peak value and average pollen concentration during the season. The obtained model fit was at a level of 64-81%. Statistical analysis shows that minimum temperature of February and March and total rainfall in June in the year preceding pollen release have the greatest effect on the birch atmospheric pollen season in Lublin. Low temperatures in February promote the occurrence of high pollen concentrations.

  6. 16 Pollen Allergens Differ From Nonallergenic Pollen Proteins by Their Lower Extent of Evolutionary Conservation

    OpenAIRE

    Radauer, Christian; Guhslc, Eva; Bublin, Merima; Breiteneder, Heimo

    2012-01-01

    Background Pollen contains hundreds of different proteins. However, only a small fraction of them have been identified to be allergenic. We aimed to test the hypothesis that most pollen proteins are non-allergenic due to their high extent of sequence conservation among non-related species. Methods Data on the composition of pollen proteomes of birch (Betula pendula), pellitory (Parientaria judaica) and timothy grass (Phleum pratense) were obtained from the literature. Sequences were downloade...

  7. Recent pollen spectra and zonal vegetation in the western USSR

    Science.gov (United States)

    Peterson, G. M.

    The relationship of modern pollen spectra to present-day vegetation is critical to the reconstruction of vegetation and climate from fossil pollen spectra. This study uses isopoll maps to illustrate the pollen-vegetation relationships in the Soviet Union west of 100°E and presents descriptive statistics for 544 modern samples of arboreal pollen and for 370 samples of herb pollen obtained from the Soviet palynological literature. Data are assembled from this large geographic region and presented in a standardized form on a scale which can be used to relate quantitative pollen data to zonal vegetation and climatic variables and to make comparisons with other regions. In order to show the relationship between pollen types and major ecotones in forested and non-forested areas, the pollen data are presented as percentages of a sum including both arboreal and non-arboreal pollen. Major pollen types which attain values of 10% or more in at least one vegetation zone include Betula (birch), Cyperaceae (sedges), Picea (spruce), Pinus (total pine), Pinus sibirica, Ericaceae (heath family), Gramineae (grasses), Artemisia (sage), and Chenopodiaceae (i.e., saltbush, Russian thistle, pigweed family). Samples from the tundra and forest-tundra have high values of Ericaceae (heath family), birch, alder, and sedge pollen. In the boreal forest, pine, spruce, and birch pollen predominate. In the mixed and deciduous forests, Tilia (linden), Quercus (oak), Ulmus (elm), and Corylus (hazel) pollen attain maximum values. In the forest-steppe and steppe zones, arboreal pollen decreases in importance and is replaced by non-arboreal pollen types. Pollen of Artemisia and Chenopodiaceae predominates in the semi-desert zones. In spite of variation in the pollen spectra arising from the use of different sediment types (soil, peat, and river sediments), and human disturbance of vegetation, the pollen spectra are clearly related to zonal vegetation. Pollen spectra from the western USSR show

  8. Are there changes in Germany regarding the start of the pollen season, the season length and the pollen concentration of the most important allergenic pollens?

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Uwe [Centre for Human Biometeorological Research, Freiburg (Germany). German Meteorological Service; Glod, Tom [Univ. of Trier (Germany). FB Physical Geography

    2011-10-15

    For the regions Northwest, Northeast and Southern Germany we examined the main allergic pollen (Hazel, Alder, Birch, grasses and Mugwort) for trends on the basis of the pollen counts of the Pollen Information Service (PID) reference-stations. From these stations information about changes on the start of the pollen season, the season length and the total amount as well as the peak-concentration of pollen during the last years (1988-2009 for Northwest and Southern Germany and 1994-2009 for Northeast Germany) are examined. Possible trends are analysed by means of the Mann-Kendall test for their significance. The results demonstrate that the changes, regarding the start of the pollen season and the total pollen amount, are strongest in Southern and Northeast Germany. Data show for all regions that tree pollen becomes the significant allergen. (orig.)

  9. T cell epitopes of the major fraction of rye grass Lolium perenne (Lol p I) defined using overlapping peptides in vitro and in vivo. I. Isoallergen clone1A.

    Science.gov (United States)

    Bungy Poor Fard, G A; Latchman, Y; Rodda, S; Geysen, M; Roitt, I; Brostoff, J

    1993-10-01

    One hundred and fifteen overlapping synthetic peptides spanning the entire sequence of the iso-allergen clone1A of Lol p I from rye grass Lolium perenne were synthesized by the multi-pin technique. The peptides were overlapping 12mers, offset by two residues and overlapping by 10 residues. Sets of six adjacent overlapping peptides (except pool-1, 15, 20) were pooled and were used in vitro and in vivo to map the T cell epitopes on Lol p I. Six atopics who were skin test and RAST positive to rye grass showed T cell responses to L. perenne extract (LPE) and its major fraction (Lol p I). Five out of six showed T cell responses in vitro to peptide pool-17, while five non-atopics did not respond to any of the peptide pools. By testing the individual peptides of pool-17, we have located the T cell epitope on Lol p I. Interestingly, when we tested pool-17 and its single peptides in vivo by intradermal skin testing we found in one patient a typical DTH after 24-48 h to pool-17 and its peptides (peptides 3 and 4) which exactly matched the in vitro responses. By defining the T cell epitopes in this way a greater understanding of the allergic response to pollen will be obtained, and a more effective and less dangerous vaccine may be possible for treating patients with hay fever.

  10. Quantitative relationship between pollen and vegetation in northern China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    205 surface pollen samples from different communities in Northern China were analyzed to understand the quantitative relationship between pollen and its original vegetation. Pollen analysis and vegetation investigation show that the pollen assemblages differ a lot in different vegetation regions. Arboreal pollen account for more than 30% in temperate broad-deciduous forests region. In temperate steppe regions, herb pollen percentages are more than 90%, where Artemisia and Chenopodiaceae are domi- nant pollen types with Artemisia percentages more than 30%. In temperate desert, Chenopodiaceae pollen percentages are more than Artemisia, where ferns are rare. Cyperaceae pollen percentages are more than 20% in sub-alpine or cold meadows. The relations between pollen percentages and vegeta- tion cover indicate that most arboreal pollen shows a close relationship with parent plant covers, most shrubby pollen types have more or less correlations, but most herbs do not show clear correlations. For arboreal pollen types, Picea pollen shows the closest correlation with spruce trees coverage, then is Quercus and Carpinus. Betula, Larix and Juglans have also high correlation coefficients with their plants coverage, but Betula pollen is of overrepresented pollen type and more than 40% in birch forest, while Larix and Juglans pollen is underrepresented and pollen percentages are more than 10% in Larix or Juglans pure forests. Pinus is of overrepresented pollen type, and pollen percentages have some relations with plants cover. Pine forest might present when Pinus pollen percentages are more than 30%. The relations between Ulmus and Populus pollen percentages and vegetation cover are not close, where they are mixed with other arbors, they cannot be recorded easily, but if their pollen percentages are more than 1%, Ulmus or Populus trees should exist. For shrubby pollen types, the correlation be- tween Vitex pollen percentages and vegetation cover is the highest, then is Corylus

  11. Quantitative relationship between pollen and vegetation in northern China

    Institute of Scientific and Technical Information of China (English)

    XU QingHai; LI YueCong; YANG XiaoLan; ZHENG ZhenHua

    2007-01-01

    205 surface pollen samples from different communities in Northern China were analyzed to understand the quantitative relationship between pollen and its original vegetation. Pollen analysis and vegetation investigation show that the pollen assemblages differ a lot in different vegetation regions. Arboreal pollen account for more than 30%in temperate broad-deciduous forests region. In temperate steppe regions, herb pollen percentages are more than 90%,where Artemisia and Chenopodiaceae are dominant pollen types with Artemisia percentages more than 30%.In temperate desert, Chenopodiaceae pollen percentages are more than Artemisia, where ferns are rare. Cyperaceae pollen percentages are more than 20% in sub-alpine or cold meadows. The relations between pollen percentages and vegetation cover indicate that most arboreal pollen shows a close relationship with parent plant covers, most shrubby pollen types have more or less correlations, but most herbs do not show clear correlations. For arboreal pollen types, Picea pollen shows the closest correlation with spruce trees coverage, then is Quercus and Carpinus. Betula, Larix and Juglans have also high correlation coefficients with their plants coverage, but Betula pollen is of overrepresented pollen type and more than 40% in birch forest, while Larix and Juglans pollen is underrepresented and pollen percentages are more than 10%in Larix or Juglans pure forests. Pinus is of overrepresented pollen type, and pollen percentages have some relations with plants cover. Pine forest might present when Pinus pollen percentages are more than 30%.The relations between Ulmus and Populus pollen percentages and vegetation cover are not close, where they are mixed with other arbors. They cannot be recorded easily, but if their pollen percentages are more than 1%,Uimus or Populus trees should exist. For shrubby pollen types, the correlation between Vitex pollen percentages and vegetation cover is the highest, then is Corylus, Tamariaceae

  12. Bee Pollen

    Science.gov (United States)

    ... It can also include some nectar and bee saliva. Pollens come from many plants, so the contents ... rash. You may hear claims that bee pollen enzymes (chemical compounds that assist in chemical reactions) provide ...

  13. Asymptomatic skin sensitization to birch predicts later development of birch pollen allergy in adults

    DEFF Research Database (Denmark)

    Bodtger, Uffe; Poulsen, Lars K.; Malling, Hans-Jørgen

    2003-01-01

    The skin prick test is the allergologic test of choice, but asymptomatic skin sensitization to aeroallergens is common. However, no data in the literature describe the clinical phenotype of asymptomatic sensitized adults....

  14. Immunoproteomic characterization of Ambrosia artemisiifolia pollen allergens in canine atopic dermatitis.

    Science.gov (United States)

    Ognjenovic, Jana; Milcic-Matic, Natalija; Smiljanic, Katarina; Vuckovic, Olga; Burazer, Lidija; Popovic, Nikola; Stanic-Vucinic, Dragana; Velickovic, Tanja Cirkovic

    2013-09-01

    Canine atopic dermatitis (CAD) is an immune system disorder that affects 10-15% of the canine population. Short ragweed (Ambrosia artemisiifolia) pollen represents one of the major seasonal sources of allergenic pollen proteins in Europe, particularly in the Pannonian valley of the Balkan region. In Serbia, about 66% of atopic dogs showed a positive intradermal skin test with its pollen extract, which is second to house dust mites. Therefore, characterization of Ambrosia artemisiifolia pollen components, in terms of defining major and minor allergens that induce clinically manifested allergic reaction in dogs, is important for valid diagnosis and efficient therapy. This study has, for the first time, characterized and identified major Ambrosia artemisiifolia allergens in CAD, using an immunoproteomic approach. To assess the prevalence of specific IgE in electrophoretically separated ragweed pollen proteins, individual reactivity of sera from dogs with CAD was analyzed and compared to the reactivity of sera from healthy dogs in the non-reducing conditions, which were found optimal for specific canine IgE detection. A specific IgE band (38 kDa) was recognized as the most dominant allergen in CAD, occurring in 81% of positive dog's sera. 2-D immunoblotting followed by a mass spectrometry peptide fingerprint analyses with pooled canine and human atopic sera, revealed that 38 kDa major Ambrosia atremisiifolia allergens in CAD were all five isoallergens of the Amb a 1 group (antigen E), including the previously named Amb a 2 (antigen K). In contrast to canine sera, human atopic sera also recognized lower mass allergens such as the β fragment of Amb a 1 and profilins (Amb a 8 variants). The most prominent ragweed proteins in CAD, represent, as in humans, variants of all five isoallergens of the Amb a 1 group (pectate lyase): Amb a 1.0101 and its natural variant E1XUL2, Amb a 1.0202, 1.0304, 1.0402 and the natural variant of Amb a 1.0501, E1XUM0, as well as the

  15. Effects of acidity on tree pollen germination and tube growth

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, J.S.; Van Rye, D.M.; Lassoie, J.P.

    1985-01-01

    Several studies have indicated that pollen germination and tube growth are adversely affected by air pollutants. Pollutants may inhibit the function of pollen by reducing the number of pollen grains which germinate, by reducing the maximum length to which the pollen tubes grow, or by interfering with the formation of the generative cell. The paper reports on studies that are attempting to determine the effects acid rain may have on these crucial stages in the life histories of northeastern tree species. The first stage of this work assessed the effects of acidity in the growth medium on in vitro pollen germination for four deciduous forest species common to central New York State, Betula lutea (yellow birch), B. lenta (black birch), Acer saccharum (sugar maple), and Cornus florida (flowering dogwood). Measurements were taken at the end of the growth period to determine the percentage of grains which had germinated, and to estimate the average tube length. To determine the effects of pollen on the growth medium, the pH of the germination drop was measured at the end of the growth period.

  16. Allergies, asthma, and pollen

    Science.gov (United States)

    Reactive airway - pollen; Bronchial asthma - pollen; Triggers - pollen; Allergic rhinitis - pollen ... Things that make allergies or asthma worse are called triggers. It is important to know your triggers because avoiding them is your first step toward feeling better. ...

  17. [The study of profile of hypersensitivity to pollen and fungal allergens in the Moscow region].

    Science.gov (United States)

    Akhapkina, I G; Krakhanenkova, S N; Dobronravova, E V; Shushpanova, E N

    2014-05-01

    The profile of hypersensitivity to pollen and fungal allergens is an important element of common pattern of immune diseases needed for development of effective pharmaceuticals. The purpose of the study was to analyze the rate of detection of combined forms of hypersensitivity to pollen and fungal allergens (pollen of birch, hazel, cocksfoot, wormwood, fungi A. alternata, C. herbarum, R. nigricans, P. notatum, C. albicans, A. fumigatus) in the Moscow region on the basis of data of scarification skin samples. The mono-sensibilization was established in 23.36% of all cases of hypersensitivity. At that, among leading allergens turned out A. alternata and cocksfoot pollen (6.54% and 4.67%), followed by allergens of wormwood pollen, P. notatum, R. nigricans, birch pollen and C. albicans (3.74%, 3.74%, 1.87%, 1.87% and 0.93% correspondingly). The polysensibilization was established in 51.40% of cases. Besides, the combined hypersensitivity to pollen allergens of plants (20.26%) and to pollen and fungal allergens (20.56%) occurred more frequently In the group of patients with polysensibilization predominated combined allergic reactions to pollen allergens and A. alternata allergens (36.36%). On the whole, most frequently occurred sensitization to allergens of birch, hazel, cocksfoot, wormwood and A. alternata allergen (76.14%, 69.32%, 57.95%, 55.68%, 39.77% and 56.82% correspondingly). In the Moscow region predominate combined forms of hypersensitivity to two and more pollen and fungal allergens. The polysensitization to pollen allergens and A. alternata allergen occurs more frequently.

  18. Interspecific variation in resistance of Asian, European, and North American birches (Betula spp.) to bronze birch borer (Coleoptera: Buprestidae).

    Science.gov (United States)

    Nielsen, David G; Muilenburg, Vanessa L; Herms, Daniel A

    2011-06-01

    Bronze birch borer (Agrilus anxius Gory) is the key pest of birches (Betula spp.) in North America, several of which have been recommended for ornamental landscapes based on anecdotal reports of borer resistance that had not been confirmed experimentally. In a 20-yr common garden experiment initiated in 1979 in Ohio, North American birch species, including paper birch (Betula papyrifera Marshall), 'Whitespire' gray birch (Betula populifolia Marshall), and river birch (Betula nigra L.), were much more resistant to bronze birch borer than species indigenous to Europe and Asia, including European white birch (Betula pendula Roth), downy birch (Betula pubescens Ehrh.), monarch birch (Betula maximowicziana Regel), and Szechuan white birch (Betula szechuanica Jansson). Within 8 yr of planting, every European white, downy, and Szechuan birch had been colonized and killed, although 100% of monarch birch had been colonized and 88% of these plants were killed after nine years. Conversely, 97% of river birch, 76% of paper birch, and 73% Whitespire gray birch were alive 20 yr after planting, and river birch showed no evidence of colonization. This pattern is consistent with biogeographic theory of plant defense: North American birch species that share a coevolutionary history with bronze birch borer were much more resistant than naïve hosts endemic to Europe and Asia, possibly by virtue of evolution of targeted defenses. This information suggests that if bronze birch borer were introduced to Europe or Asia, it could threaten its hosts there on a continental scale. This study also exposed limitations of anecdotal observation as evidence of host plant resistance.

  19. Quantifying pollen-vegetation relationships to reconstruct ancient forests using 19th-century forest composition and pollen data

    Science.gov (United States)

    Dawson, Andria; Paciorek, Christopher J.; McLachlan, Jason S.; Goring, Simon; Williams, John W.; Jackson, Stephen T.

    2016-04-01

    Mitigation of climate change and adaptation to its effects relies partly on how effectively land-atmosphere interactions can be quantified. Quantifying composition of past forest ecosystems can help understand processes governing forest dynamics in a changing world. Fossil pollen data provide information about past forest composition, but rigorous interpretation requires development of pollen-vegetation models (PVMs) that account for interspecific differences in pollen production and dispersal. Widespread and intensified land-use over the 19th and 20th centuries may have altered pollen-vegetation relationships. Here we use STEPPS, a Bayesian hierarchical spatial PVM, to estimate key process parameters and associated uncertainties in the pollen-vegetation relationship. We apply alternate dispersal kernels, and calibrate STEPPS using a newly developed Euro-American settlement-era calibration data set constructed from Public Land Survey data and fossil pollen samples matched to the settlement-era using expert elicitation. Models based on the inverse power-law dispersal kernel outperformed those based on the Gaussian dispersal kernel, indicating that pollen dispersal kernels are fat tailed. Pine and birch have the highest pollen productivities. Pollen productivity and dispersal estimates are generally consistent with previous understanding from modern data sets, although source area estimates are larger. Tests of model predictions demonstrate the ability of STEPPS to predict regional compositional patterns.

  20. Quantifying pollen-vegetation relationships to reconstruct forests using 19th-century forest composition and pollen data

    Science.gov (United States)

    Dawson, Andria; Paciorek, Christopher J.; McLachlan, Jason S.; Goring, Simon; Williams, John W.; Jackson, Stephen T.

    2016-01-01

    Mitigation of climate change and adaptation to its effects relies partly on how effectively land-atmosphere interactions can be quantified. Quantifying composition of past forest ecosystems can help understand processes governing forest dynamics in a changing world. Fossil pollen data provide information about past forest composition, but rigorous interpretation requires development of pollen-vegetation models (PVMs) that account for interspecific differences in pollen production and dispersal. Widespread and intensified land-use over the 19th and 20th centuries may have altered pollen-vegetation relationships. Here we use STEPPS, a Bayesian hierarchical spatial PVM, to estimate key process parameters and associated uncertainties in the pollen-vegetation relationship. We apply alternate dispersal kernels, and calibrate STEPPS using a newly developed Euro-American settlement-era calibration data set constructed from Public Land Survey data and fossil pollen samples matched to the settlement-era using expert elicitation. Models based on the inverse power-law dispersal kernel outperformed those based on the Gaussian dispersal kernel, indicating that pollen dispersal kernels are fat tailed. Pine and birch have the highest pollen productivities. Pollen productivity and dispersal estimates are generally consistent with previous understanding from modern data sets, although source area estimates are larger. Tests of model predictions demonstrate the ability of STEPPS to predict regional compositional patterns.

  1. Birch Stands Growth Increase in Western Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Kuzmichev, Valeriy V.; Im, Sergey T.; Ranson, Kenneth J.

    2014-01-01

    Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897-2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40-60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from approx. 63 to approx. 220 cu m/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (r(sub s) = 0.71 to 0.74), atmospheric CO2 concentration (r(sub s) = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, r(sub s) = -0.33 to -0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.

  2. A mechanistic modeling system for estimating large-scale emissions and transport of pollen and co-allergens

    Science.gov (United States)

    Efstathiou, Christos; Isukapalli, Sastry; Georgopoulos, Panos

    2011-04-01

    Allergic airway diseases represent a complex health problem which can be exacerbated by the synergistic action of pollen particles and air pollutants such as ozone. Understanding human exposures to aeroallergens requires accurate estimates of the spatial distribution of airborne pollen levels as well as of various air pollutants at different times. However, currently there are no established methods for estimating allergenic pollen emissions and concentrations over large geographic areas such as the United States. A mechanistic modeling system for describing pollen emissions and transport over extensive domains has been developed by adapting components of existing regional scale air quality models and vegetation databases. First, components of the Biogenic Emissions Inventory System (BEIS) were adapted to predict pollen emission patterns. Subsequently, the transport module of the Community Multiscale Air Quality (CMAQ) modeling system was modified to incorporate description of pollen transport. The combined model, CMAQ-pollen, allows for simultaneous prediction of multiple air pollutants and pollen levels in a single model simulation, and uses consistent assumptions related to the transport of multiple chemicals and pollen species. Application case studies for evaluating the combined modeling system included the simulation of birch and ragweed pollen levels for the year 2002, during their corresponding peak pollination periods (April for birch and September for ragweed). The model simulations were driven by previously evaluated meteorological model outputs and emissions inventories for the eastern United States for the simulation period. A semi-quantitative evaluation of CMAQ-pollen was performed using tree and ragweed pollen counts in Newark, NJ for the same time periods. The peak birch pollen concentrations were predicted to occur within two days of the peak measurements, while the temporal patterns closely followed the measured profiles of overall tree pollen

  3. Posttranslational modification of Birch and Ragweed allergen proteins by common gas phase pollutants, NO2 and O3

    Science.gov (United States)

    Mahmood, M. A.; Pope, F.; Bloss, W.

    2015-12-01

    The global incidence of hay fever has been rising for decades, however, the underlying reasons behind this rise remain unclear. It is hypothesized that exposure of pollen to common gas phase pollutants, such as nitrogen dioxide (NO2) and ozone (O3), increases the allergenicity of the pollen and thus increases hay fever incidence. Since atmospheric pollutants tend to have greater concentrations within urban areas (in particular NO2) the hypothesis suggests that greater allergenicity should occur in urban areas. Indeed, several studies do suggest higher hay fever incidence within urban areas compared to rural areas. Previous published work suggests a link between increased allergies with changes in the chemical composition of the pollen protein via posttranslational modification of the protein. This study investigates the posttranslational modification of two highly allergenic pollen species (Birch and Ragweed) that are common in Europe. Within the laboratory, we expose pollen grains to atmospherically relevant exposures of gas phase NO2, O3 and other common gas phase oxidants under a range of environmentally relevant conditions. The effects of the environmentally relevant exposures on the biochemistry of the pollen grains were probed using a proteomic approach (liquid chromatography coupled ultra-high resolution spectrometer). Our findings indicate the interaction between gas phase pollutants and pollen cause protein specific modifications; in particular, nitration occurs upon tyrosine residues and nitrosylation on cysteine residues. Possibly, these modifications may affect the immune response of the pollen protein, which may suggest a possible reason for increased allergies in reaction to such biologically altered protein. The laboratory-derived results will be supported with a time series analysis of asthma incidence rates for the London area, which take into account the pollen count, and pollutant concentrations. The implications of the results will be discussed

  4. Hypersensitivity to Parietaria officinalis pollen in newcomers to the area with the plant.

    Science.gov (United States)

    Cvitanović, S; Marusić, M; Juricić, M; Vrdoljak, E; Petrovecki, M; Rozga, A; Stavljenić-Rukavina, A

    1993-11-01

    Hypersensitivity to Parietaria officinalis (wall pellitory) pollen and other environmental allergens was studied in pollinosis patients allergic to P. officinalis pollen who were born in areas without P. officinalis and later moved to the city of Split, where P. officinalis is responsible for some 65% of pollinosis cases. Highly significant positive correlations were found for both the intensity of skin test reaction and concentration of specific serum IgE with the length of residence in the area. In contrast, the respective data on subjects hypersensitive to P. officinalis pollen allergen, but born and living in the area of Split, revealed a tendency to negative correlation between age and intensity of hypersensitivity to P. officinalis. A number of patients from both groups were tested for presence of serum IgE antibodies specific for 14 common environmental allergens. Hypersensitivity to P. officinalis pollen was associated with hypersensitivity to olive, mugwort, and birch pollen in newcomers; hypersensitivity to birch and, to some extent, olive pollen was significantly more frequent in newcomers than in autochthonous patients who were allergic to P. officinalis pollen. Regardless of whether the patients were autochthons or newcomers to the area with P. officinalis, hypersensitivity to P. officinalis mostly excluded hypersensitivity to Dermatophagoides farinae and D. pteronyssinus, and vice versa.

  5. Fraxinus pollen and allergen concentrations in Ourense (South-western Europe).

    Science.gov (United States)

    Vara, A; Fernández-González, M; Aira, M J; Rodríguez-Rajo, F J

    2016-05-01

    In temperate zones of North-Central Europe the sensitization to ash pollen is a recognized problem, also extended to the Northern areas of the Mediterranean basin. Some observations in Switzerland suggest that ash pollen season could be as important as birch pollen period. The allergenic significance of this pollen has been poorly studied in Southern Europe as the amounts of ash pollen are low. Due to the high degree of family relationship with the olive pollen major allergen (backed by a sequence identity of 88%), the Fraxinus pollen could be a significant cause of early respiratory allergy in sensitized people to olive pollen as consequence of cross-reactivity processes. Ash tree flowers in the Northwestern Spain during the winter months. The atmospheric presence of Ole e 1-like proteins (which could be related with the Fra a 1 presence) can be accurately detected using Ole e 1 antibodies. The correlation analysis showed high Spearman correlation coefficients between pollen content and rainfall (R(2)=-0.333, ppollen in the air, facilitating the wind speed its submicronic allergen proteins dispersion. In order to forecast the Fraxinus allergy risk periods, two regression equations were developed with Adjusted R(2) values around 0.48-0.49. The t-test for dependent samples shows no significant differences between the observed data and the estimated by the equations. The combination of the airborne pollen content and the allergen quantification must be assessed in the epidemiologic study of allergic respiratory diseases.

  6. EMPOL 1.0: a new parameterization of pollen emission in numerical weather prediction models

    Directory of Open Access Journals (Sweden)

    K. Zink

    2013-05-01

    Full Text Available Simulating pollen concentrations with numerical weather prediction (NWP systems requires a parameterization for pollen emission. We have developed a parameterization that is adaptable for different plant species. Both biological and physical processes of pollen emission are taken into account by parameterizing emission as a~two-step process: (1 the release of the pollen from the flowers, and (2 their entrainment into the atmosphere. Key factors influencing emission are: temperature, relative humidity, the turbulent kinetic energy and precipitation. We have simulated the birch pollen season of 2012 using the NWP system COSMO-ART, both with a parameterization already present in the model and our new parameterization EMPOL. The statistical results show that the performance of the model can be enhanced using EMPOL.

  7. Pollen evidence for late pleistocene bering land bridge environments from Norton Sound, Northeastern Bering Sea, Alaska

    Science.gov (United States)

    Ager, T.A.; Phillips, R.L.

    2008-01-01

    After more than half a century of paleoenvironmental investigations, disagreements persist as to the nature of vegetation type and climate of the Bering land bridge (BLB) during the late Wisconsin (Sartan) glacial interval. Few data exist from sites on the former land bridge, now submerged under the Bering and Chukchi Seas. Two hypotheses have emerged during the past decade. The first, based on pollen data from Bering Sea islands and adjacent mainlands of western Alaska and Northeast Siberia, represents the likely predominant vegetation on the Bering land bridge during full-glacial conditions: graminoid-herb-willow tundra vegetation associated with cold, dry winters and cool, dry summer climate. The second hypothesis suggests that dwarf birch-shrub-herb tundra formed a broad belt across the BLB, and that mesic vegetation was associated with cold, snowier winters and moist, cool summers. As a step towards resolving this controversy, a sediment core from Norton Sound, northeastern Bering Sea was radiocarbon dated and analyzed for pollen content. Two pollen zones were identified. The older, bracketed by radiocarbon ages of 29,500 and 11,515 14C yr BP, contains pollen assemblages composed of grass, sedge, wormwood, willow, and a variety of herb (forb) taxa. These assemblages are interpreted to represent graminoid-herb-willow tundra vegetation that developed under an arid, cool climate regime. The younger pollen zone sediments were deposited about 11,515 14C yr BP, when rising sea level had begun to flood the BLB. This younger pollen zone contains pollen of birch, willow, heaths, aquatic plants, and spores of sphagnum moss. This is interpreted to represent a Lateglacial dwarf birch-heath-willow-herb tundra vegetation, likely associated with a wetter climate with deeper winter snows, and moist, cool summers. This record supports the first hypothesis, that graminoid-herb-willow tundra vegetation extended into the lowlands of the BLB during full glacial conditions of the

  8. Clustering of foodstuffs in food hypersensitivity. An inquiry study in pollen allergic patients.

    Science.gov (United States)

    Eriksson, N E

    1984-01-01

    600 pollen allergic patients were questioned about hypersensitivity symptoms from various foodstuffs. The answers regarding one foodstuff were compared with those of other foodstuffs making 780 tables, from which the Spearmen 's correlation coefficients were calculated. Most of the combinations of foodstuffs showed statistically significant correlations. The highest value of the correlation coefficient was found for certain combinations: Various nuts reciprocally as well as nuts combined with apple and stone fruits. Stone fruits reciprocally and even stone fruits combined with apple and pear. Apple and pear. Kiwi fruit and avocado. Potato and carrot. Swede , parsnip and celery reciprocally. Strawberry and wild strawberry. Fish and bread, fish and cheese. Beer and wine. Several of the foodstuffs showing high degrees of correlation are known to be associated with birch pollen allergies. It is probable that at least some of these correlations are due to true IgE-mediated cross-reactivity with common allergens in birch pollen and foodstuffs. Other, hitherto less well understood mechanisms, might be at work as well. It is concluded that clustering of foodstuffs is common in food hypersensitivity and that in Sweden this phenomenon mostly is due to the association between birch pollen and some foodstuffs.

  9. Folding of Pollen Grains

    Science.gov (United States)

    Katifori, Eleni; Alben, Silas; Cerda, Enrique; Nelson, David; Dumais, Jacques

    2008-03-01

    At dehiscence, which occurs when the anther reaches maturity and opens, pollen grains dehydrate and their volume is reduced. The pollen wall deforms to accommodate the volume loss, and the deformation pathway depends on the initial turgid pollen grain geometry and the mechanical properties of the pollen wall. We demonstrate, using both experimental and theoretical approaches, that the design of the apertures (areas on the pollen wall where the stretching and the bending modulus are reduced) is critical for controlling the folding pattern, and ensures the pollen grain viability. An excellent fit to the experiments is obtained using a discretized version of the theory of thin elastic shells.

  10. The Banyan and the Birch Tree

    DEFF Research Database (Denmark)

    Lorenzen, Mark; Taeube, Florian A.

    Theoretical and empirical research on entrepreneurial networks is largely outcome-oriented and little integrated with family firm research. In this paper, we draw on social network and entrepreneurship literatures in order to investigate how family businesses build and make use of a variety...... is higher than predictions in the theoretical literature and empirical findings in cross-country studies suggest. Moreover, we show that the ‘Indian' family is an institution that dominates embedded ties. The Banyan tree symbolizes this interconnectedness of the different branches of an Indian family...... compared to the plain structure of a birch tree describing Hollywood, where embedded ties can be different from familial ties....

  11. Mapping of T cell epitopes of the major fraction of rye grass using peripheral blood mononuclear cells from atopics and non-atopics. II. Isoallergen clone 5A of Lolium perenne group I (Lol p I).

    Science.gov (United States)

    Bungy, G A; Rodda, S; Roitt, I; Brostoff, J

    1994-09-01

    Rye grass is the major cause of hay fever which currently affects 20% of the population. Lolium perenne group I (Lol p I) is a glycoprotein of 240 amino acid residues, representing the main allergen of rye grass. We have used peripheral blood mononuclear cells (PBMC) from controls and subjects allergic to rye grass and cultured them with L. perenne extract (LPE) and Lol p I and measured lymphocyte activation using thymidine incorporation. Patients were further studied against the 115 overlapping peptides of the iso-allergen clone 5A of Lol p I to see whether the 4 amino acid residue differences between clone 1A and clone 5A affect the T cell epitope and thus, lymphocyte activation. There are 24 peptide differences between isoallergen clone 1A and clone 5A occurring in pools 4, 13, 16 and 19 each one of which could be an immunodominant epitope. The PBMC from all allergic patients studied showed a strong proliferative response to LPE and Lol p I. Five immunogenic peptide pools, pool 6, 15, 16, 17 and 19 of the isoallergen clone 5A were also identified. Most of these pools are in the C-terminal region of Lol p I. Out of 20 pools tested in vitro 1 pool (pool-17) induced PBMC proliferation in five out of six patients who were not restricted to an HLA class II DR gene product. However, three out of the six subjects responded to various other peptide pools in addition to the immunodominant pool. In spite of the amino acid differences between the two clones, pool 17 still remains the immunodominant T cell epitope. Control subjects showed only weak responses to LPE and no detectable response to either Lol p I or peptide pools. From within the most active pool we have defined two peptides of the isoallergen clone 5A (identical in sequence with clone 1A) which stimulate lymphocytes from rye grass-sensitive patients in vitro. Previous studies with the two continuous sequences (193WGAVWRIDTPDK204 and 195AVWRIDTPDKLT206) tested in vivo by intradermal skin testing have shown

  12. BIRCH: A user-oriented, locally-customizable, bioinformatics system

    Directory of Open Access Journals (Sweden)

    Fristensky Brian

    2007-02-01

    Full Text Available Abstract Background Molecular biologists need sophisticated analytical tools which often demand extensive computational resources. While finding, installing, and using these tools can be challenging, pipelining data from one program to the next is particularly awkward, especially when using web-based programs. At the same time, system administrators tasked with maintaining these tools do not always appreciate the needs of research biologists. Results BIRCH (Biological Research Computing Hierarchy is an organizational framework for delivering bioinformatics resources to a user group, scaling from a single lab to a large institution. The BIRCH core distribution includes many popular bioinformatics programs, unified within the GDE (Genetic Data Environment graphic interface. Of equal importance, BIRCH provides the system administrator with tools that simplify the job of managing a multiuser bioinformatics system across different platforms and operating systems. These include tools for integrating locally-installed programs and databases into BIRCH, and for customizing the local BIRCH system to meet the needs of the user base. BIRCH can also act as a front end to provide a unified view of already-existing collections of bioinformatics software. Documentation for the BIRCH and locally-added programs is merged in a hierarchical set of web pages. In addition to manual pages for individual programs, BIRCH tutorials employ step by step examples, with screen shots and sample files, to illustrate both the important theoretical and practical considerations behind complex analytical tasks. Conclusion BIRCH provides a versatile organizational framework for managing software and databases, and making these accessible to a user base. Because of its network-centric design, BIRCH makes it possible for any user to do any task from anywhere.

  13. 75 FR 51987 - Birch Power Company and Sorenson Engineering; Birch Power Company and Sorenson Leasing L.L.C...

    Science.gov (United States)

    2010-08-24

    ... Sorenson Leasing L.L.C.; Notice of Application for Transfer of License, and Soliciting Comments and Motions... (transferors) and Birch Power Company and Sorenson Leasing, L.L.C. (transferees) filed an application for..., Birch Power Company, Sorenson Engineering, and Sorenson Leasing L.L.C., 5203 South 11th East,...

  14. Clinical relevance of [i]Corylus[/i] pollen in Poznań, western Poland

    Directory of Open Access Journals (Sweden)

    Łukasz Grewling

    2014-03-01

    Full Text Available Background. In Central Europe, hazel ([i]Corylus[/i] sp. pollen is considered to be an important aeroallergen in early spring. Objective. This study examines hazel pollen levels in Poznań, western Poland, and the clinical relevance of this aeroallergen in the city. Methods. [i]Corylus[/i] pollen data (1996–2010 were obtained by volumetric spore trap located near the centre of Poznań. Clinical data (2006–2010, i.e. skin prick test (SPT and allergen-specific IgE measurements (asIgE, were supplied by the Allergy Diseases Diagnostic Centre in Poznań. Results. Mean diurnal hazel pollen concentrations peaked around 14:00–16:00 when mean bi-hourly pollen concentrations were ~60 P m-3. Onset of the hazel pollen season varied up to 87 days annually, and was significantly (r=–0.647; p<0.01 related to mean maximum temperature during late December. SPT data revealed that ~11% of allergy patients had positive skin reactions to [i]Corylus[/i] pollen allergens, and most of these (94.4% reacted to pollen allergens from other members of the Betulaceae family – alder or birch. Of those sensitized, 53% suffered from atopic dermatitis. Of patients examined for serum asIgE, 26.0% had asIgE measurements in classes 5 and 6. Conclusions. Hazel pollen has a detrimental effect on the allergic population of Poznań, with more than half of those sensitised to hazel pollen allergens showing symptoms of atopic dermatitis. Hazel pollen concentrations reach levels recognized as being able to induce allergy symptoms, especially in the afternoon and early evening when many people are returning home from work. The cross-reactivity with other members of the Fagales order also increases the allergenic potential of hazel pollen.

  15. On impact of transport conditions on variability of the seasonal pollen index.

    Science.gov (United States)

    Sofiev, M

    2017-01-01

    This discussion paper reveals the contribution of pollen transport conditions to the inter-annual variability of the seasonal pollen index (SPI). This contribution is quantified as a sensitivity of the pollen model predictions to meteorological variability and is shown to be a noticeable addition to the SPI variability caused by plant reproduction cycles. A specially designed SILAM model re-analysis of pollen seasons 1980-2014 was performed, resulting in the 35 years of the SPI predictions over Europe, which was used to compute the SPI inter-annual variability. The current paper presents the results for birch and grass. Throughout the re-analysis, the source term formulations and habitation maps were kept constant, which allowed attributing the obtained variability exclusively to the pollen release and transport conditions during the flowering seasons. It is shown that the effect is substantial: it amounts to 10-20% (grass) and 20-40% (birch) of the observed SPI year-to-year changes reported in the literature. The phenomenon has well-pronounced spatial- and species-specific patterns. The findings were compared with observation-based statistical models for the SPI prediction, showing that such models highlight the same processes as the analysis with the SILAM model.

  16. Inter- and intra-specific variation in stem phloem phenolics of paper birch (Betula papyrifera) and European white birch (Betula pendula).

    Science.gov (United States)

    Muilenburg, V L; Phelan, P L; Bonello, P; Herms, D A

    2011-11-01

    Outbreaks of bronze birch borer (BBB) (Agrilus anxius), a wood-boring beetle endemic to North America, have been associated with widespread mortality of birch (Betula spp.). There is substantial inter- and intra-specific variation in birch resistance to BBB. Species endemic to North America, such as paper birch (B. papyrifera), have coevolved with BBB and are more resistant than European and Asian birch species, such as European white birch (B. pendula), which lack an evolutionary history with BBB. Borer larvae feed on stem phloem tissue. Therefore, in search of potential resistance mechanisms against BBB, we compared the constitutive phenolic profile of stem phloem tissue of paper birch with that of European white birch. We also analyzed intraspecific variation in phenolic composition among clones and/or half-siblings of both species. Three phenolics (coumaroylquinic acid, betuloside pentoside A, and a diarylheptanoid hexoside) were detected only in paper birch, and concentrations of six other phenolics were significantly higher in paper birch. These differences may contribute to the high resistance of paper birch to BBB relative to European white birch. There was significant intraspecific variation in four of 17 phenolics found in paper birch and in five of 14 found in European white birch, but clones and half-siblings within each species could not be distinguished by phenolic composition using multivariate analysis.

  17. Induction of Eosinophilic Esophagitis by Sublingual Pollen Immunotherapy

    Directory of Open Access Journals (Sweden)

    Stephan Miehlke

    2013-09-01

    Full Text Available Sublingual immunotherapy (SLIT is increasingly investigated and utilized for the treatment of food and pollen allergies. Previous case reports suggested that eosinophilic esophagitis (EoE might develop as a long-term complication in children after completion of oral immunotherapy. Here, we describe a 44-year-old female with a medical history of pollinosis who for the first time in her life developed complete manifestation of EoE (peak eosinophils 164/high power field 4 weeks after initiation of SLIT using specific soluble allergens (hazelnut, birch, alder according to previous specific serum IgE testing. After discontinuation of SLIT, EoE resolved completely within 4 weeks without any other medical intervention. During a follow-up of 12 months the patient remained free of any esophageal symptoms. This is the first case report demonstrating a close and therefore likely causative association between pollen SLIT and EoE in an adult patient.

  18. Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2013-03-01

    Full Text Available Exposure to bioaerosol allergens such as pollen can cause exacerbations of allergenic airway disease (AAD in sensitive populations, and thus cause serious public health problems. Assessing these health impacts by linking the airborne pollen levels, concentrations of respirable allergenic material, and human allergenic response under current and future climate conditions is a key step toward developing preventive and adaptive actions. To that end, a regional-scale pollen emission and transport modeling framework was developed that treats allergenic pollens as non-reactive tracers within the WRF/CMAQ air-quality modeling system. The Simulator of the Timing and Magnitude of Pollen Season (STaMPS model was used to generate a daily pollen pool that can then be emitted into the atmosphere by wind. The STaMPS is driven by species-specific meteorological (temperature and/or precipitation threshold conditions and is designed to be flexible with respect to its representation vegetation species and plant functional types (PFTs. The hourly pollen emission flux was parameterized by considering the pollen pool, friction velocity, and wind threshold values. The dry deposition velocity of each species of pollen was estimated based on pollen grain size and density. An evaluation of the pollen modeling framework was conducted for southern California for the period from March to June 2010. This period coincided with observations by the University of Southern California's Children's Health Study (CHS, which included O3, PM2.5, and pollen count, as well as measurements of exhaled nitric oxide in study participants. Two nesting domains with horizontal resolutions of 12 km and 4 km were constructed, and six representative allergenic pollen genera were included: birch tree, walnut tree, mulberry tree, olive tree, oak tree, and brome grasses. Under the current parameterization scheme, the modeling framework tends to underestimate walnut and peak oak pollen

  19. Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease

    Science.gov (United States)

    Zhang, R.; Duhl, T.; Salam, M. T.; House, J. M.; Flagan, R. C.; Avol, E. L.; Gilliland, F. D.; Guenther, A.; Chung, S. H.; Lamb, B. K.; VanReken, T. M.

    2014-03-01

    Exposure to bioaerosol allergens such as pollen can cause exacerbations of allergenic airway disease (AAD) in sensitive populations, and thus cause serious public health problems. Assessing these health impacts by linking the airborne pollen levels, concentrations of respirable allergenic material, and human allergenic response under current and future climate conditions is a key step toward developing preventive and adaptive actions. To that end, a regional-scale pollen emission and transport modeling framework was developed that treats allergenic pollens as non-reactive tracers within the coupled Weather Research and Forecasting Community Multiscale Air Quality (WRF/CMAQ) modeling system. The Simulator of the Timing and Magnitude of Pollen Season (STaMPS) model was used to generate a daily pollen pool that can then be emitted into the atmosphere by wind. The STaMPS is driven by species-specific meteorological (temperature and/or precipitation) threshold conditions and is designed to be flexible with respect to its representation of vegetation species and plant functional types (PFTs). The hourly pollen emission flux was parameterized by considering the pollen pool, friction velocity, and wind threshold values. The dry deposition velocity of each species of pollen was estimated based on pollen grain size and density. An evaluation of the pollen modeling framework was conducted for southern California (USA) for the period from March to June 2010. This period coincided with observations by the University of Southern California's Children's Health Study (CHS), which included O3, PM2.5, and pollen count, as well as measurements of exhaled nitric oxide in study participants. Two nesting domains with horizontal resolutions of 12 and 4 km were constructed, and six representative allergenic pollen genera were included: birch tree, walnut tree, mulberry tree, olive tree, oak tree, and brome grasses. Under the current parameterization scheme, the modeling framework tends to

  20. Development of a regional-scale pollen emission and transport modeling framework for investigating the impact of climate change on allergic airway disease.

    Science.gov (United States)

    Zhang, Rui; Duhl, Tiffany; Salam, Muhammad T; House, James M; Flagan, Richard C; Avol, Edward L; Gilliland, Frank D; Guenther, Alex; Chung, Serena H; Lamb, Brian K; VanReken, Timothy M

    2013-03-01

    Exposure to bioaerosol allergens such as pollen can cause exacerbations of allergenic airway disease (AAD) in sensitive populations, and thus cause serious public health problems. Assessing these health impacts by linking the airborne pollen levels, concentrations of respirable allergenic material, and human allergenic response under current and future climate conditions is a key step toward developing preventive and adaptive actions. To that end, a regional-scale pollen emission and transport modeling framework was developed that treats allergenic pollens as non-reactive tracers within the WRF/CMAQ air-quality modeling system. The Simulator of the Timing and Magnitude of Pollen Season (STaMPS) model was used to generate a daily pollen pool that can then be emitted into the atmosphere by wind. The STaMPS is driven by species-specific meteorological (temperature and/or precipitation) threshold conditions and is designed to be flexible with respect to its representation of vegetation species and plant functional types (PFTs). The hourly pollen emission flux was parameterized by considering the pollen pool, friction velocity, and wind threshold values. The dry deposition velocity of each species of pollen was estimated based on pollen grain size and density. An evaluation of the pollen modeling framework was conducted for southern California for the period from March to June 2010. This period coincided with observations by the University of Southern California's Children's Health Study (CHS), which included O3, PM2.5, and pollen count, as well as measurements of exhaled nitric oxide in study participants. Two nesting domains with horizontal resolutions of 12 km and 4 km were constructed, and six representative allergenic pollen genera were included: birch tree, walnut tree, mulberry tree, olive tree, oak tree, and brome grasses. Under the current parameterization scheme, the modeling framework tends to underestimate walnut and peak oak pollen concentrations, and tends

  1. The influence of hybridization on epidermal properties of birch species and the consequences for palaeoclimatic interpretations

    NARCIS (Netherlands)

    Wagner, F.; Kürschner, W.M.; Neuvonen, S.; Visscher, H.

    2000-01-01

    The Fennoscandian birch population primarily consists of Betula nana, B. pendula and B. pubescens ssp. czerepanovii, the Mountain birch. Frequent hybridization between the Mountain birch and B. nana generates a wide range of genotypic and phenotypic plasticity in the subarctic birch zone of Fennosca

  2. Aerobiological study of pollen and mold in Seoul, Korea

    Directory of Open Access Journals (Sweden)

    Jae-Won Oh

    1998-01-01

    Full Text Available In a large number of allergic individuals, inhalant allergens are important causative and triggering agents in respiratory allergies. It is essential to survey the pollen and mold around the patient’s environment for the diagnosis and treatment of airborne allergy. Rotorod samplers were installed at well-ventilated places in seven collecting stations in Seoul, the capital of Korea, which has a population of 12 million. Airborne particles carrying allergens were collected daily from each station for 2 years (1 October 1995 to 30 September 1997. After being stained with Calberla’s fuchsin, they were identified, counted and recorded. The weather in Seoul was also recorded. Pollen was found from the middle of February through to the end of December. The peak date for pollen was 12 May (peak mean daily count: 701 grains/m3/day and for mold it was 23 June (peak mean daily count: 936 spores/m3/day. Alder, birch, pine, oak, maple, elm, juniper, willow, and gingko trees were prevalent during the tree season, lasting from the middle of February to late July. Then sagebrush, ragweed, Japanese hop, and pigweed followed during the weed season, which lasts from the middle of July to the end of December. In skin prick test results, house dust mite was the most common positive allergen in Seoul, followed by cockroach. Among the pollens, mugwort was the most common positive, followed by ragweed mix, alder, birch, and grasses mix. Among the molds, there were high counts of Cladosporium and Alternaria during the year, excluding January. Ascospore of Lepto-spheria was highest during the monsoon season.

  3. Methods for estimating production and utilization of paper birch saplings

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Development of technique to estimate browse production and utilization. Developed a set of methods for estimating annual production and utilization of paper birch...

  4. Grass pollen symptoms interfere with the recollection of birch pollen symptoms - a prospective study of suspected, asymptomatic skin sensitization

    DEFF Research Database (Denmark)

    Assing, K; Bodtger, U; Poulsen, Lars K.

    2007-01-01

    Asymptomatic skin sensitization (AS) is a risk factor for the development of allergic symptoms. A meticulous definition of this condition requires a systematic assessment of clinical symptoms before inclusion.......Asymptomatic skin sensitization (AS) is a risk factor for the development of allergic symptoms. A meticulous definition of this condition requires a systematic assessment of clinical symptoms before inclusion....

  5. Boreal pollen contain ice-nucleating as well as ice-binding ‘antifreeze’ polysaccharides

    Science.gov (United States)

    Dreischmeier, Katharina; Budke, Carsten; Wiehemeier, Lars; Kottke, Tilman; Koop, Thomas

    2017-01-01

    Ice nucleation and growth is an important and widespread environmental process. Accordingly, nature has developed means to either promote or inhibit ice crystal formation, for example ice-nucleating proteins in bacteria or ice-binding antifreeze proteins in polar fish. Recently, it was found that birch pollen release ice-nucleating macromolecules when suspended in water. Here we show that birch pollen washing water exhibits also ice-binding properties such as ice shaping and ice recrystallization inhibition, similar to antifreeze proteins. We present spectroscopic evidence that both the ice-nucleating as well as the ice-binding molecules are polysaccharides bearing carboxylate groups. The spectra suggest that both polysaccharides consist of very similar chemical moieties, but centrifugal filtration indicates differences in molecular size: ice nucleation occurs only in the supernatant of a 100 kDa filter, while ice shaping is strongly enhanced in the filtrate. This finding may suggest that the larger ice-nucleating polysaccharides consist of clusters of the smaller ice-binding polysaccharides, or that the latter are fragments of the ice-nucleating polysaccharides. Finally, similar polysaccharides released from pine and alder pollen also display both ice-nucleating as well as ice-binding ability, suggesting a common mechanism of interaction with ice among several boreal pollen with implications for atmospheric processes and antifreeze protection. PMID:28157236

  6. Boreal pollen contain ice-nucleating as well as ice-binding ‘antifreeze’ polysaccharides

    Science.gov (United States)

    Dreischmeier, Katharina; Budke, Carsten; Wiehemeier, Lars; Kottke, Tilman; Koop, Thomas

    2017-02-01

    Ice nucleation and growth is an important and widespread environmental process. Accordingly, nature has developed means to either promote or inhibit ice crystal formation, for example ice-nucleating proteins in bacteria or ice-binding antifreeze proteins in polar fish. Recently, it was found that birch pollen release ice-nucleating macromolecules when suspended in water. Here we show that birch pollen washing water exhibits also ice-binding properties such as ice shaping and ice recrystallization inhibition, similar to antifreeze proteins. We present spectroscopic evidence that both the ice-nucleating as well as the ice-binding molecules are polysaccharides bearing carboxylate groups. The spectra suggest that both polysaccharides consist of very similar chemical moieties, but centrifugal filtration indicates differences in molecular size: ice nucleation occurs only in the supernatant of a 100 kDa filter, while ice shaping is strongly enhanced in the filtrate. This finding may suggest that the larger ice-nucleating polysaccharides consist of clusters of the smaller ice-binding polysaccharides, or that the latter are fragments of the ice-nucleating polysaccharides. Finally, similar polysaccharides released from pine and alder pollen also display both ice-nucleating as well as ice-binding ability, suggesting a common mechanism of interaction with ice among several boreal pollen with implications for atmospheric processes and antifreeze protection.

  7. Stabilization of the dimeric birch pollen allergen Bet v 1 impacts its immunological properties.

    Science.gov (United States)

    Kofler, Stefan; Ackaert, Chloé; Samonig, Martin; Asam, Claudia; Briza, Peter; Horejs-Hoeck, Jutta; Cabrele, Chiara; Ferreira, Fatima; Duschl, Albert; Huber, Christian; Brandstetter, Hans

    2014-01-03

    Many allergens share several biophysical characteristics, including the capability to undergo oligomerization. The dimerization mechanism in Bet v 1 and its allergenic properties are so far poorly understood. Here, we report crystal structures of dimeric Bet v 1, revealing a noncanonical incorporation of cysteine at position 5 instead of genetically encoded tyrosine. Cysteine polysulfide bridging stabilized different dimeric assemblies, depending on the polysulfide linker length. These dimers represent quaternary arrangements that are frequently observed in related proteins, reflecting their prevalence in unmodified Bet v 1. These conclusions were corroborated by characteristic immunologic properties of monomeric and dimeric allergen variants. Hereby, residue 5 could be identified as an allergenic hot spot in Bet v 1. The presented results refine fundamental principles in protein chemistry and emphasize the importance of protein modifications in understanding the molecular basis of allergenicity.

  8. Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

    Directory of Open Access Journals (Sweden)

    Chiang Vincent L

    2009-09-01

    Full Text Available Abstract Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth. would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch lines expressing quaking aspen (Populus tremuloides L. caffeate/5-hydroxyferulate O-methyltransferase (PtCOMT under the 35S cauliflower mosaic virus (CaMV promoter showed a reduction in the relative expression of a putative silver birch COMT (BpCOMT gene and, consequently, a decrease in the lignin syringyl/guaiacyl composition ratio. Alterations were also detected in concentrations of certain phenolic compounds. All PtCOMT silver birch lines produced normal ectomycorrhizas with the ectomycorrhizal fungus Paxillus involutus (Batsch: Fr., and the formation of symbiosis enhanced the growth of the transgenic plants. Conclusion The down-regulation of BpCOMT in the 35S-PtCOMT lines caused a reduction in the syringyl/guaiacyl ratio of lignin, but no significant effect was seen in the composition or quantity of phenolic compounds that would have been caused by the expression of PtCOMT under the 35S or UbB1 promoter. Moreover, the detected alterations in the composition of lignin and secondary phenolic compounds had no effect on the interaction between silver birch and P. involutus.

  9. Birch Creek, Alaska, a wild and scenic river analysis: Preliminary draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Upper Birch Creek, Alaska possessed values which qualify it for inclusion in the National Wild and Scenic Rivers System. The upper Birch Creek and its immediate...

  10. The growth process of natural poplar-birch forests

    Institute of Scientific and Technical Information of China (English)

    LAN Shibo; LUO Xu; LUO Yuliang

    2006-01-01

    With a combination of permanent and temporary sample plots,we investigated the growth conditions of natural poplar-birch forests.The forests were divided into four site classes,using statistical and analytical techniques in a quantitative model,in descending order where site class I was the best.On this basis,the growth of natural poplar-birch forests in the different site classes was studied.The growth processes of height and diameter at breast height were divided into three stages:a fast growing period,a stable growing period and a slow growing period.Results of this study provide a theoretical basis for the directive cultivation of natural poplar-birch forests.

  11. Purification, characterization and N-terminal amino acid sequence of a new major allergen from European chestnut pollen--Cas s 1.

    Science.gov (United States)

    Kos, T; Hoffmann-Sommergruber, K; Ferreira, F; Hirschwehr, R; Ahorn, H; Horak, F; Jager, S; Sperr, W; Kraft, D; Scheiner, O

    1993-11-15

    Pollens from trees of the order Fagales (e.g. birch, alder, hazel, and hornbeam) all contain one major allergen--the main cause for tree pollen allergy. So far the major allergens from birch (Bet v 1), alder (Aln g 1), hazel (Cor a 1), and hornbeam (Car b 1) have been characterized, showing high sequence similarity with each other (1-4). We present the molecular and immunologic characterization of Cas s 1, the major allergen from the European chestnut (Castanea sativa). From aqueous pollen extracts from European chestnut a protein was purified to homogeneity and was subjected to further investigation. The protein revealed a Mr of 22 kDa and was shown to represent the major allergen of the European chestnut (immunoblotting, histamine release) and designated Cas s 1. Despite a marked difference in Mr, Cas s 1 shows significant amino acid sequence similarity at the N-terminus and is antigenically closely related to the major birch pollen allergen Bet v 1 (17 kDa), as shown by binding to the anti-Bet v 1 monoclonal antibody BIP-1 and by IgE-inhibition tests using recombinant Bet v 1.

  12. A review of bronze birch borer (Coleoptera: Buprestidae) life history, ecology, and management.

    Science.gov (United States)

    Muilenburg, Vanessa L; Herms, Daniel A

    2012-12-01

    Bronze birch borer (Agrilus anxius Gory) (Coleoptera: Buprestidae), a specialist wood-borer endemic to North America, is prone to periodic outbreaks that have caused widespread mortality of birch (Betula spp.) in boreal and north temperate forests. It is also the key pest of birch in ornamental landscapes. Amenity plantings have extended the distribution of birch in North America, for which we report an updated map. Life history and phenology also are summarized. Larvae feed primarily on phloem tissue of stems and branches, which can girdle and kill trees. Stressors such as drought, elevated temperature, and defoliation predispose trees to bronze birch borer colonization and trigger outbreaks, which implicates the availability of suitable host material in the bottom-up regulation of populations. Stress imposed by climate change may increase the frequency of outbreaks and alter the distribution of birch. Bronze birch borer has a diverse array of natural enemies, but their role in top-down population regulation has not been studied. There is substantial interspecific variation in resistance to this insect. North American species share a coevolutionary history with bronze birch borer and are much more resistant than Eurasian species, which are evolutionarily naïve. Potential resistance mechanisms are reviewed. The high susceptibility of Eurasian birch species and climatic similarities of North America and Eurasia create high risk of widespread birch mortality in Eurasia if the borer was inadvertently introduced. Bronze birch borer can be managed in amenity plantings through selection of resistant birch species, plant health care practices, and insecticides.

  13. Cytoskeleton in Pollen and Pollen Tubes of Ginkgo biloba L.

    Institute of Scientific and Technical Information of China (English)

    Jun-Mei LIU; Hong ZHANG; Yan LI

    2005-01-01

    The distribution of F-actin and microtubules was investigated in pollen and pollen tubes of Ginkgo biloba L. using a confocal laser scanning microscope after fluorescence and immunofluorescence labeling. A dense F-actin network was found in hydrated Ginkgo pollen. When Ginkgo pollen was germinating,F-actin mesh was found under the plasma membrane from which the pollen tube would emerge. After pollen germination, F-actin bundles were distributed axially in long pollen tubes of G. biloba. Thick F-actin bundles and network were found in the tip of the Ginkgo pollen tube, which is opposite to the results reported for the pollen tubes of some angiosperms and conifers. In addition, a few circular F-actin bundles were found in Ginkgo pollen tubes. Using immunofluorescence labeling, a dense microtubule network was found in hydrated Ginkgo pollen under confocal microscope. In the Ginkgo pollen tube, the microtubules were distributed along the longitudinal axis and extended to the tip. These results suggest that the cytoskeleton may have an essential role in the germination of Ginkgo pollen and tube growth.

  14. Pollen Viability and Pollen Tube Attrition in Cranberry (Vaccinium macrocarpon)

    Science.gov (United States)

    The content of mature seed in a cranberry fruit increases with stigmatic pollen load. On average, however, only two seeds result for every tetrad of pollen deposited. What then is the fate of the two remaining pollen grains fused in each tetrad? Germination in vitro revealed that most of the grains ...

  15. Pollen morphology of the Stemonaceae

    NARCIS (Netherlands)

    Ham, van der R.W.J.M.

    1991-01-01

    A pollen-morphological survey of all four genera of the Stemonaceae at the light and electron microscope level is presented. Stemonaceae is a eurypalynous family. Stichoneuron pollen, up to now described as monosulcate, appears to be inaperturate. Pentastemona pollen is most deviating in Stemonaceae

  16. Characteristics of T-cell and B-cell immune respoonses to pollen allergens in Bulgarian patients with pollinosis

    Directory of Open Access Journals (Sweden)

    ZHIVKA KOSTOVA

    2015-12-01

    Full Text Available Characterization of the pollen allergens and identification of the main T-cell and B-cell epitopes is of crucial importance, since the clarification of the cellular and molecular mechanisms will allow long-term control of this type allergic diseases and development of safe immunotherapeutic medication. The objective of this study was to identify which pollen allergens are responsible for the T-cell activation in atopic patients with pollinosis and to determine whether the same allergens are responsible for the IgE-mediated reactions. Thirty-seven patients with pollinosis and thirteen non-allergic subjects were recruited. Peripheral blood samples were collected out of the pollen season. T-cell responses (IFN-γ production towards different pollen allergens and levels of pollen specific IgE and IgG in the sera were measured by ELISA. The T-cell reactivity in most patients was directed towards the grass pollen B1, tree pollen I and autumn pollen B5. 70% of the allergic individuals responded to allergens from Lolium perenne, 84% to Dactylis glomerata, 11% to Phleum pratense, 65% to Betula pendula and 70% to Taxus baccata. Elevated serum levels of specific IgE in the allergic patients (p<0.01 were measured against the tree pollen I and autumn pollen, which include widespread deciduous trees (birch, willow, poplar and yew and Artemisia absinthium, respectively. Our results show that the T-cell reactivity and antibody responses may be directed towards different or the same allergens. In addition, we propose that short synthetic peptides, which contain overlapping T- and B-cell epitopes can be used for specific immunotherapy treatment if they lack antibody recognition domains.

  17. Central and Eastern European Spring Pollen Allergens and Their Expression Analysis—State of the Art

    Directory of Open Access Journals (Sweden)

    Jana Žiarovská

    2016-10-01

    Full Text Available Spring pollinosis has become a part of life for many people throughout the world. A wide range of knowledge about the allergenic potential of individual pollen allergen types is documented well, but the starting point of the pollen allergens expression regulation in plants itself is still not fully answered. Expression analysis of pollen allergens does not yet have any specific protocols or methods developed, despite a very good sequence background available in public bioinformatics databases. However, research in this area of interest has a great application potential for breeding and biotechnology of allergenic plants that may benefit from the knowledge of the expression of allergen coding genes in individual varieties or genotypes. Here, a brief review of up-to-date knowledge about the coding sequences of central and eastern European spring pollen allergens is introduced together with real-time based analysis of the expression of two of the main pollen allergens–PR protein type and profilin type of birch and hazelnut.

  18. Predicting onset and duration of airborne allergenic pollen season in the United States

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Cai, Ting; Mi, Zhongyuan; Georgopoulos, Panos

    2015-02-01

    Allergenic pollen is one of the main triggers of Allergic Airway Disease (AAD) affecting 5%-30% of the population in industrialized countries. A modeling framework has been developed using correlation and collinearity analyses, simulated annealing, and stepwise regression based on nationwide observations of airborne pollen counts and climatic factors to predict the onsets and durations of allergenic pollen seasons of representative trees, weeds and grass in the contiguous United States. Main factors considered are monthly, seasonal and annual mean temperatures and accumulative precipitations, latitude, elevation, Growing Degree Day (GDD), Frost Free Day (FFD), Start Date (SD) and Season Length (SL) in the previous year. The estimated mean SD and SL for birch (Betula), oak (Quercus), ragweed (Ambrosia), mugwort (Artemisia) and grass (Poaceae) pollen season in 1994-2010 are mostly within 0-6 days of the corresponding observations for the majority of the National Allergy Bureau (NAB) monitoring stations across the contiguous US. The simulated spatially resolved maps for onset and duration of allergenic pollen season in the contiguous US are consistent with the long term observations.

  19. Aeroallergen analyses and their clinical relevance. II. Sampling by high-volume airsampler with immunochemical quantification versus Burkard pollen trap sampling with morphologic quantification

    DEFF Research Database (Denmark)

    Johnsen, C R; Weeke, E R; Nielsen, J

    1992-01-01

    , was analysed, and close correlations between the 2 sampling techniques were found (rs 0.5-0.8, p .... Pollen counts and immunochemical estimation were compared with the symptom score recordings of allergic persons for birch season 1989 and for grass seasons 1986, 1988, and 1989. A close correlation was found for both sampling techniques for the grass seasons in 1986 and 1989 (rs 0.51-0.61, p

  20. Comparative Proteomic Analysis of Arabidopsis Mature Pollen and Germinated Pollen

    Institute of Scientific and Technical Information of China (English)

    Junjie Zou; Lianfen Song; Wenzheng Zhang; Yi Wang; Songlin Ruan; Wei-Hua Wu

    2009-01-01

    Proteomic analysis was applied to generating the map of Arabidopsis mature pollen proteins and analyzing the differentially expressed proteins that are potentially involved in the regulation of Arabidopsis pollen germination. By applying 2-D electrophoresis and silver staining, we resolved 499 and 494 protein spots from protein samples extracted from pollen grains and pollen tubes, respectively. Using the matrix-assisted laser desorption ionization time-of-flight mass spectrometry method, we identified 189 distinct proteins from 213 protein spots expressed in mature pollen or pollen tubes, and 75 new identified proteins that had not been reported before in research into the Arabidopsis pollen proteome. Comparative analysis revealed that 40 protein spots exhibit reproducible significant changes between mature pollen and pollen tubes. And 21 proteins from 17 downregulated and six upregulated protein spots were identified. Functional category analysis indicated that these differentially expressed proteins mainly involved in signaling, cellular structure, transport, defense/stress responses, transcription, metabolism, and energy production. The patterns of changes at protein level suggested the important roles for energy metabolism-related proteins in pollen tube growth, accompanied by the activation of the stress response pathway and modifications to the cell wall.

  1. Evaluation of sewage sludge impact on pine and birch development

    OpenAIRE

    Vaitkutė, Dovilė

    2009-01-01

    Sewage sludge could be used in forestry as enrichment of soil properties. It is also expected that sewage sludge which is rich in phosphorus, nitrogen and organic material can enhance the growth of tree seedlings in poor soils. Our study was performed in Taruskos experimental forest site in Panevezys region. The experimental site amended with industrial sewage sludge ten years ago was afforestated with birch and pine seedlings. The aim of our thesis is to evaluate the influence of sewage ...

  2. Pollen indicators of human activity

    Institute of Scientific and Technical Information of China (English)

    LI YiYin; ZHOU LiPing; CUI HaiTing

    2008-01-01

    The study of past human activities and their environmental effect is high in the agenda of global change research. A record of pollen assemblages is one of the most common proxies employed for detecting the impact of human activities on the landscape. In this review, we provide a summary and discussion on the recent progress on the use of pollen as indicators of human activity. For most of the studies related to human impact, the following features have been focused on: (1) decline of certain tree pollen; (2) flourishing of pioneer plant pollen; (3) concomitant occurrence of cereal-type pollen and cropland weed pollen; (4) abrupt changes in pollen concentration and richness; and (5) occurrence of nitrophilous plants and pastoral weed. Pollen of anthropogenic plants (weeds and cereal-type plants) is ideal indicators of human activities. Different types of human activities will result in different pollen assem-blages. Patterns of human-impacted pollen spectra would vary between forested areas and grassland. In the study of human impact with pollen data, high resolution in both time and space must be consid-ered. High resolution in space will help to inform the complexity of the landscape. More importantly, it can help to reveal the interference of human activities on the landscape, hence avoiding the bias cre-ated by the limited data points. Fine resolution in time will make accurate recording of short-lived events possible, hence avoiding the exclusion of events related to human activities. The combination of palynology with other proxies will help to decipher more accurately landscape changes through time. Charcoal is a particularly useful proxy for recording the disturbance of humans on vegetation. Its peak values usually occur with pronounced drop of tree pollen and significant rise of anthropogenic pollen.

  3. Allergy to cypress pollen.

    Science.gov (United States)

    Charpin, D; Calleja, M; Lahoz, C; Pichot, C; Waisel, Y

    2005-03-01

    Although Cupressus sempervirens has been spread over southern Europe since antiquity, cypress pollen allergy has not been reported until 1945. In France, the very first case reports were published in 1962. Since then, the prevalence of cypress pollinosis seems to demonstrate an upward trend, concomitantly with the increased use of cypress trees as ornamental plants, as wind breaks and as hedges. Hyposensitization, using improved pollen extracts, is increasingly prescribed. Besides, prevention measures begin to be implemented. Such measures include avoidance of planting new cypress trees, especially near human populations' centres, trimming of cypress hedges before the pollination season and agronomical research for hypoallergenic trees. Altogether, such new developments in cypress allergy deserve an update review.

  4. Survival and growth for pubescent birch, pendula birch and common alder growing on farmland areas; Oeverlevnad och tillvaext hos glasbjoerk, vaartbjoerk och klibbal planterade paa aakermark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Tord

    2000-07-01

    Pendula birches (Betula pendula Roth) and pubescent birches (Betula pubescens Ehrh.) were planted on former farmland. Before planting, the ground was harrowed or the ground was sprayed with terbuthylazine. Tree shelters were used as protection against weeds, voles and wild habitat. Birches treated with terbuthylazine showed the lowest survival. Birches growing in tree shelters were tallest and those growing on spots treated with terbuthylazine were smallest. The diameter at 0.1 m did not differ in a statistically significant way between the treatments. In another experiment with different herbicides, common alder (Alnus glutinosa (L.) Gaertn.) and pendula birch (Betula pendula Roth) were planted on former farmland that had been treated with glyphosate, terbuthylazine and propyzamide or after ground had been harrowed or not treated. In the study on herbicide-treated plants, birch had the highest plant survival. Mostly, species treated with glyphosate were thicker than species treated in other ways. Both species appeared sensitive to terbuthylazine, but not to glyphosate. Birch was not sensitive for propyzamide in opposite to alder. Some practical recommendations concerning afforestation of former farmland, especially weeding, are given.

  5. ANTIBIOTIC RESISTANCE OF ESCHERICHIA COLI ISOLATED FROM UKRAINIAN BETULA VERRUCOSA EHRH. POLLEN AFTER MICROBIOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Tetiana Shevtsova

    2013-08-01

    Full Text Available Seven samples of silver birch pollen from different habitat of Ukraine were investigated in order to estimate their contamination with the Enterobacteriaceae family, anaerobic bacteria and fungi. Also resistance of 108 strains of Escherichia coli isolated from seven samples of Ukrainian Betula verrucosa Ehrh. pollen against 5 antibiotics: ampicillin, chloramphenicol, meropenem, ceftriaxone and ofloxacin were determined. Disc diffusion method was used for antibiotic suceptibility testing according to EUCAST 2012. It is established the concentrations of enterobacteria ranged from 0.00 to 4.16 log cfu/g, of anaerobic bacteria – 2.48 to 4.90 log cfu/g and concentration of fungi ranged from 2.48 to 4.14 log cfu/g. Degree of pollen contamination is different depending on the habitats. The resistance of E. coli isolates was determined against ampicillin, chloramphenicol, meropenem and ofloxacin. But intermediate resistance in the 33.3% of E. coli isolates and susceptibility in the 8.3% to ceftriaxone was found out. Antibiotic resistance was evaluated for all samples of pollen in whole.

  6. [Cypress pollen allergy].

    Science.gov (United States)

    Charpin, D; Calleja, M; Pichot, C; Penel, V; Hugues, B; Poncet, P

    2013-12-01

    Cypress belongs to the Cupressaceae family, which includes 140 species with non-deciduous foliage. The most important genera in allergic diseases are Cupressus sempervirens or Green cypress, Cupressus arizonica or Blue cypress, Juniperus oxycedrus, Juniperus communis and Thuya. Because J. oxycedrus pollinates in October, C. sempervirens in January and February, C. arizonica in February and March, J. communis in April, the symptomatic period is long-lasting. Because of global warming, the pollination period is tending to last longer and Cupressaceae species are becoming established further the north. In Mediterranean countries, cypress is by far the most important pollinating species, accounting for half of the total pollination. The major allergens belong to group 1. The other allergens from cypress and Juniper share 75 to 97 % structural homology with group 1 major allergens. The prevalence of cypress allergy in the general population ranges from 5 % to 13 %, according to exposure to the pollen. Among outpatients consulting an allergist, between 9 and 35 %, according to different studies, are sensitized to cypress pollen. Repeated cross-sectional studies performed at different time intervals have demonstrated a threefold increase in the percentage of cypress allergy. Risk factors include a genetic predisposition and/or a strong exposure to pollen, but air pollutants could play a synergistic role. The study of the natural history of cypress allergy allows the identification of a subgroup of patients who have no personal or family history of atopy, whose disease began later in life, with low total IgE and often monosensitization to cypress pollen. In these patients, the disease is allergic than rather atopic. In the clinical picture, rhinitis is the most prevalent symptom but conjunctivitis the most disabling. A cross-reactivity between cypress and peach allergy has been demonstrated. The pharmacological treatment of cypress allergy is not different from

  7. Holocene rapid climatic changes in the Okhotsk Sea and Amur watershed based on pollen analysis

    Science.gov (United States)

    Kokfelt, U.; Tiedemann, R.; Nuernberg, D.; Biebow, N.; Kozdon, R.; Lembke, L.; Kaiser, A.

    2003-04-01

    Recent investigations in the Sea of Okhotsk reveal high resolution records of rapid past climatic and vegetation pattern changes within this marginal sea and the adjacent Amur river drainage basin. The watershed of the Amur undergoes exteme seasonal as well as longer term climatic changes. A humid SE-Asia monsoon regime in summer is contrasted by cold, dry continental climate of Siberia in wintertime. Thus this region is crucial for our understanding of complex changes and shifts of athmospheric systems in the subarctic Far East and western North Pacific region. Gravity core LV28-4-4 was recovered from the continental margin off NE Sakhalin. Our age model consists of 16 AMS radiocarbon control points from planktic foraminifera and benthic shell fragments fit together by ninth order polynomial regressions. According to this, sedimentation rates exceed 100cm/kyr. Thus to date our investigations gain a temporal resolution of 200-600 years between discrete samples. We use analysis of terrestrial pollen and freshwater algae as proxies for vegetation changes in the Amur catchment area and the adjacent Siberian hinterland. Within this 930 cm long sequence, four pollen zones were distinguished: Pollen zone I (12,600-11,800 years BP), which comprises the Younger Dryas event, was dominated by non-arboreale taxa such as grasses (gramineae) and sedges (cyperaceae). The following pollen zone II (11,800-8,500 years BP) was in general dominated by birch (Betula) and elder (Alnus). The rise of spruce-dominated taiga (Picea jezoensis and P. glehnii) is clearly seen to the end of this zone and shows the preboreal warming. The oldest part of the pollen zone II has distinctly high values of birch and spruce and very low values of gramineae and cyperaceae suggesting a period of intense warming. Pollenzone III (8,500-3,600 years BP) is dominated by darkneedled taiga components and increased oak (Quercus) values and reflects the Holocene climatic optimum. The latest pollen zone IV

  8. Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily

    Directory of Open Access Journals (Sweden)

    Bagnato S

    2014-04-01

    Full Text Available Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily. The aim of this paper is to evaluate the dynamics of Etna birch stands (Betula aetnensis Rafin following the cessation of silvicultural activities in the Etna Regional Park (Sicily. We investigated forest structure, natural regeneration, vegetation and deadwood in different forest types. Our findings highlighted three different dynamics for birch populations: stable birch stands in the high mountain area which might represent an edapho-climax forest; progressive dynamic birch stands in the intermediate mountain area, showing a gradual depletion of birch and a concomitant replacement with monospecific stands (calabrian pine, beech, oaks or mixed ones (with birch; pure birch stands (typical that tend to be regressive - especially under stressful conditions - and to be replaced by xerophilous grasslands. Following the cessation of coppicing and with stand ageing, the stumps transformation into more homogeneous stand structures have been increasing. Within the context of protected areas the restoration of coppice selection system (with appropriate adaptations could help to maintain the traditional forest landscape, acting as a silvicultural technique with low environmental and landscape impact.

  9. 78 FR 15681 - Beaverhead-Deerlodge National Forest, Dillon Ranger District; Montana; Birch, Willow, Lost Project

    Science.gov (United States)

    2013-03-12

    ... Forest Service Beaverhead-Deerlodge National Forest, Dillon Ranger District; Montana; Birch, Willow, Lost... statement. SUMMARY: The Birch, Willow, Lost Project proposes to treat vegetation communities in the four sub.... FR 7476 (Lower Willow Creek) would have 1.7 miles Spot Reconstructed. FR 8200 (Willow Creek)...

  10. Field performance of chitinase transgenic silver birches (Betula pendula): resistance to fungal diseases.

    Science.gov (United States)

    Pasonen, H-L; Seppänen, S-K; Degefu, Y; Rytkönen, A; von Weissenberg, K; Pappinen, A

    2004-08-01

    A field trial of 15 transgenic birch lines expressing a sugar beet chitinase IV gene and the corresponding controls was established in southern Finland to study the effects of the level of sugar beet chitinase IV expression on birch resistance to fungal diseases. The symptoms caused by natural infections of two fungal pathogens, Pyrenopeziza betulicola (leaf spot disease) and Melampsoridium betulinum (birch rust), were analysed in the field during a period of 3 years. The lines that had shown a high level of sugar beet chitinase IV mRNA accumulation in the greenhouse also showed high sugar beet chitinase IV expression after 3 years in the field. The level of sugar beet chitinase IV expression did not significantly improve the resistance of transgenic birches to leaf spot disease. Instead, some transgenic lines were significantly more susceptible to leaf spot than the controls. The level of sugar beet chitinase IV expression did have an improving effect on most parameters of birch rust; the groups of lines showing high or intermediate transgene expression were more resistant to birch rust than those showing low expression. This result indicates that the tested transformation may provide a tool for increasing the resistance of silver birch to birch rust.

  11. Pollen rain and pollen representation across a forest-páramo ecotone in northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.; Duivenvoorden, J.F.; Hooghiemstra, H.

    2009-01-01

    Modern pollen spectra were studied in forest and páramo vegetation from the Guandera area, northern Ecuador. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with the pollen spectra in moss polsters and pollen traps. In total, 73 pollen taxa

  12. A Simple Method for Collecting Airborne Pollen

    Science.gov (United States)

    Kevan, Peter G.; DiGiovanni, Franco; Ho, Rong H.; Taki, Hisatomo; Ferguson, Kristyn A.; Pawlowski, Agata K.

    2006-01-01

    Pollination is a broad area of study within biology. For many plants, pollen carried by wind is required for successful seed set. Airborne pollen also affects human health. To foster studies of airborne pollen, we introduce a simple device--the "megastigma"--for collecting pollen from the air. This device is flexible, yielding easily obtained data…

  13. CHARACTERIZATION OF THE MAIZE POLLEN TRANSCRIPTOME

    Science.gov (United States)

    Pollen is a primary vehicle for transgene flow from engineered plants to their non-transgenic, native or weedy relatives. Hence, gene flow will be affected by pollen fitness (e.g., how well a particular pollen grain can outcompete other pollen present on the stigma and complete ...

  14. Pollen dimorphism and androgenesis in Hordeum vulgare

    Directory of Open Access Journals (Sweden)

    Krystyna Idzikowska

    2014-01-01

    Full Text Available Dimorphism of binucleate pollen grains of Hordeum vulgare has been confirmed. It is considered, however, in contrast to the accepted opinions, that some of the large pollen grains with dense cytoplasm lying close to the tapetum are the outset forms for embryoids, and not the small pollen grains with scarce cytoplasm lying in the pollen sac centre.

  15. Geochemistry of the Birch Creek Drainage Basin, Idaho

    Science.gov (United States)

    Swanson, Shawn A.; Rosentreter, Jeffrey J.; Bartholomay, Roy C.; Knobel, LeRoy L.

    2003-01-01

    The U.S. Survey and Idaho State University, in cooperation with the U.S. Department of Energy, are conducting studies to describe the chemical character of ground water that moves as underflow from drainage basins into the eastern Snake River Plain aquifer (ESRPA) system at and near the Idaho National Engineering and Environmental Laboratory (INEEL) and the effects of these recharge waters on the geochemistry of the ESRPA system. Each of these recharge waters has a hydrochemical character related to geochemical processes, especially water-rock interactions, that occur during migration to the ESRPA. Results of these studies will benefit ongoing and planned geochemical modeling of the ESRPA at the INEEL by providing model input on the hydrochemical character of water from each drainage basin. During 2000, water samples were collected from five wells and one surface-water site in the Birch Creek drainage basin and analyzed for selected inorganic constituents, nutrients, dissolved organic carbon, tritium, measurements of gross alpha and beta radioactivity, and stable isotopes. Four duplicate samples also were collected for quality assurance. Results, which include analyses of samples previously collected from four other sites, in the basin, show that most water from the Birch Creek drainage basin has a calcium-magnesium bicarbonate character. The Birch Creek Valley can be divided roughly into three hydrologic areas. In the northern part, ground water is forced to the surface by a basalt barrier and the sampling sites were either surface water or shallow wells. Water chemistry in this area was characterized by simple evaporation models, simple calcite-carbon dioxide models, or complex models involving carbonate and silicate minerals. The central part of the valley is filled by sedimentary material and the sampling sites were wells that are deeper than those in the northern part. Water chemistry in this area was characterized by simple calcite-dolomite-carbon dioxide

  16. Reproductive Biology of ViciaL. I. Pollen morphology, Pollen Germination ( in situ) and Pollen Tube Growth.

    OpenAIRE

    Dane, Feruzan; MERİÇ, Çiler

    1999-01-01

    This paper is a study of the pollen germination of V. hirsuta (L.) S.F. Gray, V. pannonica Crantz., V. hybrida L., V, grandiflora Scop., V. sativa L, V. nrbonnensis L. in the anther loculi ( in situ). The morphological properties and fertilities of the pollen were had been investigated. In addition, cytological and cytochemical properties and fertilities of the pollen were had been investigated. In addition, cytological and cytochemical properites of the pollen tubes during in situ pollen...

  17. City scale pollen concentration variability

    Science.gov (United States)

    van der Molen, Michiel; van Vliet, Arnold; Krol, Maarten

    2016-04-01

    Pollen are emitted in the atmosphere both in the country-side and in cities. Yet the majority of the population is exposed to pollen in cities. Allergic reactions may be induced by short-term exposure to pollen. This raises the question how variable pollen concentration in cities are in temporally and spatially, and how much of the pollen in cities are actually produced in the urban region itself. We built a high resolution (1 × 1 km) pollen dispersion model based on WRF-Chem to study a city's pollen budget and the spatial and temporal variability in concentration. It shows that the concentrations are highly variable, as a result of source distribution, wind direction and boundary layer mixing, as well as the release rate as a function of temperature, turbulence intensity and humidity. Hay Fever Forecasts based on such high resolution emission and physical dispersion modelling surpass traditional hay fever warning methods based on temperature sum methods. The model gives new insights in concentration variability, personal and community level exposure and prevention. The model will be developped into a new forecast tool to serve allergic people to minimize their exposure and reduce nuisance, coast of medication and sick leave. This is an innovative approach in hay fever warning systems.

  18. Main: POLLEN1LELAT52 [PLACE

    Lifescience Database Archive (English)

    Full Text Available POLLEN1LELAT52 S000245 26-October-2005 (last modified) kehi One of two co-dependent regulatory ele... -68 region; See S000246 (POLLEN2LELAT52); AGAAA and TCCACCATA (S000246) are required for pollen specific ex...ments responsible for pollen specific activation of tomato (L.e.) lat52 gene; Found at -72 to...gene (Filichkin et al. 2004); pollen; lat52; endo-beta-mannnanase; MAN; Lycopersicon esculentum (tomato) AGAAA ...

  19. Main: POLLEN2LELAT52 [PLACE

    Lifescience Database Archive (English)

    Full Text Available POLLEN2LELAT52 S000246 11-Oct-1999 (last modified) kehi One of two co-dependent regulatory ele... region; See S000245 (POLLEN1LELAT52); AGAAA (S000245) and TCCACCATA are required for pollen specific expression; pollen; lat52; tomato (Lycopersicon esculentum) TCCACCATA ... ...ments responsible for pollen specific activation of tomato (L.e.) lat52 gene; Found at -60 to -52

  20. Pollen germination and pollen tube growth in ZP maize lines

    Directory of Open Access Journals (Sweden)

    Cerović Radosav

    2014-01-01

    Full Text Available The study was conducted on the in vitro pollen germination at 26°, 28°, 32° and 35°C for 24h of male parental lines, pollen tube growth in vivo in cross pollination of female and male parental lines that make couples in four hybrids: ZP 504 su (♀ ZPPL 51 × ♂ ZPPL 67; ZP 677 (♀ ZPPL 17 × ♂ ZPPL 201; ZP 704 (♀ ZPPL 109 × ♂ ZPPL 79, ZP 611 k (♀ ZPPL 126 × ♂ ZPPL 105, and the open pollination of female parental lines of the above mentioned hybrids. Pollen germination in vitro and pollen tube growth dynamics in vivo showed different genotypic specificities with the tests applied. The obtained results were discussed in the context of reproductive biology of ZP maize lines and aimed to create the preconditions for successful management and direction of the process in practice - seed production in certain environmental conditions.

  1. Sensitization rates of airborne pollen and mold in children

    Directory of Open Access Journals (Sweden)

    So Hyun Park

    2012-09-01

    Full Text Available &lt;B&gt;Purpose:&lt;/b&gt; Aeroallergens are important causative factors of allergic diseases. Previous studies on aeroallergen sensitization rates investigated patients groups that had visited pediatric allergy clinics. In contrast, we investigated sensitization rates in a general population group of elementary school to teenage students in Incheon, Jeju, and Ulsan. &lt;b&gt;Methods:&lt;/B&gt; After obtaining parental consent, skin-prick tests were performed on 5,094 students between March and June 2010. Elementary school students were tested for 18 common aeroallergens, whereas middle and high school students were tested for 25 allergens. The 25 allergens included &lt;I&gt;Dermatophagoides pteronyssinus, Dermatophagoides farinae&lt;/I&gt;, pollen (birch, alder, oak, Japanese cedar, pine, willow, elm, maple, Bermuda grass, timothy grass, rye grass, orchard grass, meadow grass, vernal grass, mugwort, Japanese hop, fat hen, ragweed, and plantain, and mold (&lt;I&gt;Penicillatum, Aspergillus, Cladosporium, and Alternaria&lt;/I&gt;. &lt;b&gt;Results:&lt;/b&gt; The sensitization rates in descending order were 25.79% (&lt;I&gt;D. pteronyssinus&lt;/I&gt; , 18.66% (&lt;I&gt;D. farinae&lt;/I&gt; , 6.20% (mugwort, and 4.07% (willow in Incheon; 33.35% (&lt;I&gt;D. pteronyssinus&lt;/I&gt; , 24.78% (&lt;I&gt;D. farinae&lt;/I&gt;, 15.36% (Japanese cedar, and 7.33% (Alternaria in Jeju; and 32.79% (D. pteronyssinus, 30.27% (D. farinae, 10.13% (alder, and 8.68% (birch in Ulsan. The dust mite allergen showed the highest sensitization rate among the 3 regions. The sensitization rate of tree pollen was the highest in Ulsan, whereas that of Alternaria was the highest in Jeju. The ragweed sensitization rates were 0.99% in Incheon, 1.07% in Jeju, and 0.81% in Ulsan. &lt;b&gt;Conclusion:&lt;/b&gt; The

  2. ALKALINE PRETREATMENT OF SPRUCE AND BIRCH TO IMPROVE BIOETHANOL AND BIOGAS PRODUCTION

    Directory of Open Access Journals (Sweden)

    Azam Jeihanipour

    2010-05-01

    Full Text Available Alkaline pretreatment with NaOH under mild operating conditions was used to improve ethanol and biogas production from softwood spruce and hardwood birch. The pretreatments were carried out at different temperatures between minus 15 and 100ºC with 7.0% w/w NaOH solution for 2 h. The pretreated materials were then enzymatically hydrolyzed and subsequently fermented to ethanol or anaerobically digested to biogas. In general, the pretreatment was more successful for both ethanol and biogas production from the hardwood birch than the softwood spruce. The pretreatment resulted in significant reduction of hemicellulose and the crystallinity of cellulose, which might be responsible for improved enzymatic hydrolyses of birch from 6.9% to 82.3% and spruce from 14.1% to 35.7%. These results were obtained with pretreatment at 100°C for birch and 5°C for spruce. Subsequently, the best ethanol yield obtained was 0.08 g/g of the spruce while pretreated at 100°C, and 0.17 g/g of the birch treated at 100°C. On the other hand, digestion of untreated birch and spruce resulted in methane yields of 250 and 30 l/kg VS of the wood species, respectively. The pretreatment of the wood species at the best conditions for enzymatic hydrolysis resulted in 83% and 74% improvement in methane production from birch and spruce.

  3. Direct Emission of Methyvinylketone from Birch (\\textit{betula pendula})

    Science.gov (United States)

    Folkers, A.; Koppmann, R.; Wildt, J.

    2002-12-01

    Volatile organic compounds (VOCs) are of central importance for the chemistry of the troposphere. They have a significant impact on photochemical processes that lead to the formation of ozone and other photooxidants in the planetary boundary layer. With estimated global emission rates of 520 Tg yr {-1} [Guenther \\textit{et al.} 1995], biogenic emissions of short chained oxygenated VOCs (SOVOCs) like methanol, ethanol, acetaldehyde, and acetone cannot be neglected for atmospheric chemistry. In addition to the direct emission by plants SOVOCs are produced by chemical reactions of VOCs in the atmosphere. For some SOVOCs such as methanol, acetone, or leaf alcohols it is known that they have a large biogenic source strength. Other SOVOCs are believed to be only produced by atmospheric processes. For example methacrolein, and methylvinylketone (MVK) are believed to be exclusively produced during atmospheric isoprene oxidation. Thus, up to now the only known source of MVK in the atmosphere is the oxidation of VOCs like isoprene. We analysed SOVOC emissions from different plant species under well defined conditions in our plant chambers and determined the temperature- and light intensity dependence of their emission rates. During these measurements we also observed a direct MVK emission from birch. The emission rates exhibit a temperature and light intensity dependence. Artificial MVK formation was excluded by a series of experiments. Due to the direct emission of MVK probably also from other plant species than birch, measurements of ambient concentrations of this compound have to be carefully investigated. The fact that there may be a primary source for MVK has to be considered in model calculations concerning the photochemistry and the concentrations of OH radicals in the lower troposphere. \\begin{thebibliography}{} \\bibitem[Guenther \\textit{et al.} 1995]{Guenther1995} Guenther, A., Hewitt, C. N., Erickson, D., Fall, R., Geron, C., Graedel, T., Harley, P., Klinger, L

  4. Wavelet Based Fractal Analysis of Airborne Pollen

    CERN Document Server

    Degaudenzi, M E

    1999-01-01

    The most abundant biological particles in the atmosphere are pollen grains and spores. Self protection of pollen allergy is possible through the information of future pollen contents in the air. In spite of the importance of airborne pol len concentration forecasting, it has not been possible to predict the pollen concentrations with great accuracy, and about 25% of the daily pollen forecasts have resulted in failures. Previous analysis of the dynamic characteristics of atmospheric pollen time series indicate that the system can be described by a low dimensional chaotic map. We apply the wavelet transform to study the multifractal characteristics of an a irborne pollen time series. We find the persistence behaviour associated to low pollen concentration values and to the most rare events of highest pollen co ncentration values. The information and the correlation dimensions correspond to a chaotic system showing loss of information with time evolution.

  5. Atmospheric pollen count in Monterrey, Mexico.

    Science.gov (United States)

    González-Díaz, Sandra N; Rodríguez-Ortiz, Pablo G; Arias-Cruz, Alfredo; Macías-Weinmann, Alejandra; Cid-Guerrero, Dagoberto; Sedo-Mejia, Giovanni A

    2010-01-01

    There are few reports of pollen count and identification in Mexico; therefore, it is important to generate more information on the subject. This study was designed to describe the prevalence of pollen in the city of Monterrey, Mexico, during the year 2004. Atmospheric pollen was collected with a Hirst air sampler, with an airflow of 10 L/minute during 2004. Pollen was identified with light microscopy; the average monthly pollen count as well as total was calculated from January 2004 to January 2005. The months with the highest concentration of pollen were February and March (289 and 142 grains/m(3) per day, respectively), and July and November had the lowest concentration (20 and 11 grains/m(3) per day, respectively). Most of the pollen recollected corresponded to tree pollen (72%). Fraxinus spp had the highest concentration during the year (19 grains/m(3) per day; 27.5% of the total concentration of pollen). Tree pollen predominated from January through March; with Fraxinus spp, Morus spp, Celtis spp, Cupressus spp, and Pinus spp as the most important. Weed pollen predominated in May, June, and December and the most frequently identified, were Amaranthaceae/Chenopodiaceae, Ambrosia spp, and Parietaria spp. The highest concentration of grass pollen was reported during the months of May, June, September, October, and December with Gramineae/Poaceae predominating. Tree pollen was the most abundant during the year, with the ash tree having the highest concentration. Weed and grass pollen were perennial with peaks during the year.

  6. Effect of birch (Betula spp.) and associated rhizoidal bacteria on the degradation of soil polyaromatic hydrocarbons, PAH-induced changes in birch proteome and bacterial community

    Energy Technology Data Exchange (ETDEWEB)

    Tervahauta, Arja I. [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland)], E-mail: arja.tervahauta@uku.fi; Fortelius, Carola [EVTEK University of Applied Sciences, Vantaa (Finland); Tuomainen, Marjo [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Akerman, Marja-Leena [EVTEK University of Applied Sciences, Vantaa (Finland); Rantalainen, Kimmo [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Sipilae, Timo [Department of Biological and Environmental Sciences, University of Helsinki (Finland); Lehesranta, Satu J.; Koistinen, Kaisa M.; Kaerenlampi, Sirpa [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Yrjaelae, Kim [Department of Biological and Environmental Sciences, University of Helsinki (Finland)

    2009-01-15

    Two birch clones originating from metal-contaminated sites were exposed for 3 months to soils (sand-peat ratio 1:1 or 4:1) spiked with a mixture of polyaromatic hydrocarbons (PAHs; anthracene, fluoranthene, phenanthrene, pyrene). PAH degradation differed between the two birch clones and also by the soil type. The statistically most significant elimination (p {<=} 0.01), i.e. 88% of total PAHs, was observed in the more sandy soil planted with birch, the clearest positive effect being found with Betula pubescens clone on phenanthrene. PAHs and soil composition had rather small effects on birch protein complement. Three proteins with clonal differences were identified: ferritin-like protein, auxin-induced protein and peroxidase. Differences in planted and non-planted soils were detected in bacterial communities by 16S rRNA T-RFLP, and the overall bacterial community structures were diverse. Even though both represent complex systems, trees and rhizoidal microbes in combination can provide interesting possibilities for bioremediation of PAH-polluted soils. - Birch can enhance degradation of PAH compounds in the rhizosphere.

  7. Changes in flowering of birch in the Czech Republic in recent 25 years (1991–2015 in connection with meteorological variables

    Directory of Open Access Journals (Sweden)

    Lenka Hajkova

    2015-12-01

    Full Text Available The paper presents the results of long-term phenological observations of silver birch (Betula pendula during the years 1991–2015 across the phenological network of the Czech Hydrometeorological Institute (CHMI – Český hydrometeorologický ústav. The data assembled over this period were used for identification of timing of generative phenophases associated with pollen release into the air: inflorescence emergence 10%, beginning of flowering 10%, beginning of flowering 50%, beginning of flowering 100%, and end of flowering. The stations are situated at altitudes from 155 m (Doksany to 1102 m (Modrava. The average timing of beginning of flowering 10% was 8th April (Lednice = lowland station and 14th May (Modrava = mountain station; the average timing of beginning of flowering 50% was 12th April (Lednice and 20th May (Modrava; the average timing of beginning of flowering 100% was 18th April (Lednice and 22nd May (Modrava, and the average timing of end of flowering was 26th April (Lednice and 28th May (Modrava. The totals of effective temperatures above 5°C (TS5 and sums of daily precipitation were used as a bio-climatological criterion for assessment of the dependence of phenological phases on meteorological variables. The average sums of TS5 and the average sums of daily precipitation total were as follows: 61.0–80.8°C, 82.8–327.4 mm (inflorescence emergence; 105.2–106.4°C, 85.9–365.2 mm (beginning of flowering 10%; 124.8–130.8°C, 89.8–385.9 mm (beginning of flowering 50%; 144.7–158.6°C, 95.2–390.7 mm (beginning of flowering 100%; and 181.6–223.8°C, 104.7–427.4 mm (end of flowering. Synoptic situations occurring during interphase intervals were obtained – the most often found synoptic situations were B (stationary trough over Central Europe, Bp (east travelling trough, NEa (northeast anticyclonic situation, Sa (south anticyclonic situation and SWc2 (southwest cyclonic situation moving northeast to eastwards. The

  8. Pollen Forecast and Dispersion Modelling

    Science.gov (United States)

    Costantini, Monica; Di Giuseppe, Fabio; Medaglia, Carlo Maria; Travaglini, Alessandro; Tocci, Raffaella; Brighetti, M. Antonia; Petitta, Marcello

    2014-05-01

    The aim of this study is monitoring, mapping and forecast of pollen distribution for the city of Rome using in-situ measurements of 10 species of common allergenic pollens and measurements of PM10. The production of daily concentration maps, associated to a mobile phone app, are innovative compared to existing dedicated services to people who suffer from respiratory allergies. The dispersal pollen is one of the most well-known causes of allergic disease that is manifested by disorders of the respiratory functions. Allergies are the third leading cause of chronic disease and it is estimated that tens millions of people in Italy suffer from it. Recent works reveal that during the last few years there was a progressive increase of affected subjects, especially in urban areas. This situation may depend: on the ability to transport of pollutants, on the ability to react between pollutants and pollen and from a combination of other irritants, existing in densely populated and polluted urban areas. The methodology used to produce maps is based on in-situ measurements time series relative to 2012, obtained from networks of air quality and pollen stations in the metropolitan area of Rome. The monitoring station aerobiological of University of Rome "Tor Vergata" is located at the Department of Biology. The instrument used to pollen monitoring is a volumetric sampler type Hirst (Hirst 1952), Model 2000 VPPS Lanzoni; the data acquisition is carried out as reported in Standard UNI 11008:2004 - "Qualità dell'aria - Metodo di campionamento e conteggio dei granuli pollinici e delle spore fungine aerodisperse" - the protocol that describes the procedure for measuring of the concentration of pollen grains and fungal spores dispersed into the atmosphere, and reported in the "Manuale di gestione e qualità della R.I.M.A" (Travaglini et. al. 2009). All 10 allergenic pollen are monitored since 1996. At Tor Vergata university is also operating a meteorological station (SP2000, CAE

  9. [A case of anaphylaxis due to rose-flavored soft-serve ice cream with pollen food allergy syndrome].

    Science.gov (United States)

    Kitabayashi, Taeru; Sato, Sayuri; Adachi, Mitsuru

    2013-05-01

    We experienced a 10-year-old boy who had anaphylaxis after eating rose-flavored soft-serve ice cream. The patient felt a sense of discomfort in his throat when eating apple, peach, loquat, Japanese pear, and kiwi fruit. Therefore, we measured specific IgE antibodies to allergen components by ImmunoCAP ISAC. Consequently, the patient gave positive results for all PR-10 proteins from birch, alder, hazel, apple, peach, peanut, hazelnut, and soybean, so we diagnosed him with Pollen Food Allergy Syndrome (PFAS) induced by cross reactivity with pollens of birch family and fruits of rose family. When we conducted the skin prick test as is for red rose syrup because of the belief that anaphylaxis was caused by the rose ingredient contained in rose-flavored soft-serve ice cream, the patient gave a strong positive result. However, the results were negative for rose essence and Food Red No. 2 contained. Subsequently, it was found that red rose syrup contained apple juice. Therefore, we conducted the prick-prick test for apple, and the patient was confirmed to be strongly positive to apple. We thus identified apple as the cause of anaphylaxis. Since there is no legal obligation of labeling specific raw materials when directly selling manufactured and processed food products to general consumers, it is possible for general consumers to mistakenly take them in without knowing the containment of allergic substances. It is believed that the labeling method should be improved in the future.

  10. Quantification of C uptake in subarctic birch forest after setback by an extreme insect outbreak

    DEFF Research Database (Denmark)

    Heliasz, Michal; Johansson, Torbjörn; Lindroth, Anders

    2011-01-01

    The carbon dynamics of northern natural ecosystems contribute significantly to the global carbon balance. Periodic disturbances to these dynamics include insect herbivory. Larvae of autumn and winter moths (Epirrita autumnata and Operophtera brumata) defoliate mountain birch (Betula pubescens) fo...

  11. THE INFLUENCE OF CATIONIZED BIRCH XYLAN ON WET AND DRY STRENGTH OF FINE PAPER

    Directory of Open Access Journals (Sweden)

    Janne Kataja-aho,

    2012-02-01

    Full Text Available Cationized birch xylan was prepared and its use as a papermaking chemical was evaluated. The focus was on studying the effects of cationized birch xylan on the wet and dry strength of fine paper. The results of the laboratory experiments show that the addition of 3 percent of cationized birch xylan to birch kraft pulp improved the initial wet strength of the web by 30 percent compared to base stock at a solids content of 55%. Furthermore, the tensile stiffness of the wet web increased by approximately a third and the dry tensile strength improved by 26%, while the dry elastic modulus was not changed. The improvements in the strength properties were clear when compared to the base stock, but not as high as achieved with conventionally used cationized starch. The difference between the xylan and starch is most likely due to the shorter polymer chain length of the cationized xylan.

  12. Local variation in mountain birch spring phenology along an altitudinal gradient in northern coastal Fennoscandia

    OpenAIRE

    Sjöskog, Maja Sofia

    2011-01-01

    Currently there is a lack of spring phenology studies covering small-scale altitudinal gradients of mountain birch in coastal northern Fennoscandia, a region characterized by exceptionally high precipitation of snow, which gives reason to investigate the influence of snow cover on birch budburst in this area. Furthermore, ground phenology studies are today increasingly replaced by satellite data studies, but only too rarely is the latter approach properly validated. In order to provide a bett...

  13. Pollen Aquaporins: The Solute Factor

    Science.gov (United States)

    Pérez Di Giorgio, Juliana A.; Soto, Gabriela C.; Muschietti, Jorge P.; Amodeo, Gabriela

    2016-01-01

    In the recent years, the biophysical properties and presumed physiological role of aquaporins (AQPs) have been expanded to specialized cells where water and solute exchange are crucial traits. Complex but unique processes such as stomatal movement or pollen hydration and germination have been addressed not only by identifying the specific AQP involved but also by studying how these proteins integrate and coordinate cellular activities and functions. In this review, we referred specifically to pollen-specific AQPs and analyzed what has been assumed in terms of transport properties and what has been found in terms of their physiological role. Unlike that in many other cells, the AQP machinery in mature pollen lacks plasma membrane intrinsic proteins, which are extensively studied for their high water capacity exchange. Instead, a variety of TIPs and NIPs are expressed in pollen. These findings have altered the initial understanding of AQPs and water exchange to consider specific and diverse solutes that might be critical to sustaining pollen’s success. The spatial and temporal distribution of the pollen AQPs also reflects a regulatory mechanism that allowing a properly adjusting water and solute exchange. PMID:27881985

  14. National Allergy Bureau Pollen and Mold Report

    Science.gov (United States)

    ... the Expert Search Search AAAAI National Allergy Bureau Pollen and Mold Report Date: April 11, 2017 Location: ... 11, 2017 Click Here to View Most Recent Pollen and Spore Levels (04/10/2017) If you ...

  15. Differential IgE sensitization to cypress pollen associated to a basic allergen of 14 kDa.

    Science.gov (United States)

    Shahali, Youcef; Sutra, Jean-Pierre; Charpin, Denis; Mari, Adriano; Guilloux, Laurence; Sénéchal, Hélène; Poncet, Pascal

    2012-04-01

    The common cypress (Cupressus sempervirens) (Cups) pollen represents the first cause of respiratory allergies in the Mediterranean basin. The aim of this study was to characterize a novel 14-kDa cypress pollen allergen (BP14) allowing a clear dissociation of IgE sensitization patterns among allergic patients. The biochemical and immunochemical characterization of BP14 included determination of its isoelectric point, molecular mass, extraction kinetics, IgE binding prevalence, the presence of bromelain-type cross-reactive carbohydrate determinant and its IgE reactivity under reducing conditions. The presence of potential cross-reactive homologues in closely related cypress species, i.e. Cupressus arizonica (Cupa) and Cryptomeria japonica (Cryj), as well as in several taxonomically unrelated species was also investigated. According to our results, BP14 is easily and quickly solubilized in phosphate-buffered saline and exhibits several allergenic isoforms covering a broad range of pI (6.5-10.5). This allergen displays heat-stable conformational epitopes and does not include cross-reactive carbohydrate determinants, in contrast to high molecular weight cypress allergens. BP14 is expressed at higher levels in Cups than in Cupa and Cryj. No IgE cross-reactivity was found between the 14-kDa Cups pollen protein and proteins from some other non-Cupressaceae pollen allergenic sources such as orchard, timothy, wheat, maize, birch, ash and pine. Thus, IgE reactivity to BP14 is specific to Cupressaceae and discriminates two groups of patients allergic to cypress pollen. It might correspond to a relevant marker in relation to the sensitization process and/or the symptoms observed in some cypress-pollen-allergic patients. Furthermore, the description of BP14 should improve the diagnosis of cypress pollinosis.

  16. Pollen dispersal analysis using DNA markers

    OpenAIRE

    Wei Zhou; Hong Wang

    2014-01-01

    Modes of pollen dispersal are important for plant ecology, conservation, and evolutionary biology as pollen-mediated gene flow connects one generation of sexually-reproducing plants to the next. With the development of DNA molecular techniques, molecular markers (especially microsatellite markers) have replaced traditional physical markers for pollen flow analysis. Methods of paternity assignment with maximum likelihood and Bayesian inference have greatly improved the estimation of pollen flo...

  17. Stigma-pollen recognition: a new look

    Directory of Open Access Journals (Sweden)

    C. Dumas

    2014-01-01

    Full Text Available During the last two decades, there have been several conceptual developments in our understanding of pollen-stigma recognition and molecular mechanisms involved. The main models proposed are compared. Based on additional data a hypothesis to complete these models especially for pollen hydration and adhesion is proposed. After attachment of the pollen to the stigma surface a close interaction exists involving lipoproteic membrane-like compounds (pollenkitt and stigma pellicle and pollen agglutinating ability.

  18. Pollen Allergens for Molecular Diagnosis.

    Science.gov (United States)

    Pablos, Isabel; Wildner, Sabrina; Asam, Claudia; Wallner, Michael; Gadermaier, Gabriele

    2016-04-01

    Pollen allergens are one of the main causes of type I allergies affecting up to 30% of the population in industrialized countries. Climatic changes affect the duration and intensity of pollen seasons and may together with pollution contribute to increased incidences of respiratory allergy and asthma. Allergenic grasses, trees, and weeds often present similar habitats and flowering periods compromising clinical anamnesis. Molecule-based approaches enable distinction between genuine sensitization and clinically mostly irrelevant IgE cross-reactivity due to, e. g., panallergens or carbohydrate determinants. In addition, sensitivity as well as specificity can be improved and lead to identification of the primary sensitizing source which is particularly beneficial regarding polysensitized patients. This review gives an overview on relevant pollen allergens and their usefulness in daily practice. Appropriate allergy diagnosis is directly influencing decisions for therapeutic interventions, and thus, reliable biomarkers are pivotal when considering allergen immunotherapy in the context of precision medicine.

  19. METAL ION SORPTION TO BIRCH AND SPRUCE WOOD

    Directory of Open Access Journals (Sweden)

    Pingping Su,

    2012-02-01

    Full Text Available Sorption of metal ions from aqueous solutions to birch wood and spruce heartwood and sapwood has been studied. Functional groups in wood were determined by acid-base titrations. The sorption of metal ions to wood of the different tree species was investigated by a column chromatographic technique. The mechanism of sorption is mainly ion exchange by complexation of metal ions to the functional groups, e.g. carboxyl groups and phenolic hydroxyl groups, in the wood phase. By combination of the sorption experiments with four different metal ion mixtures, the following affinity order was established for spruce sapwood particles: Fe3+>>Pb2+>>Cu2+>>Fe2+>Cd2+>Zn2+>Ni2+>Mn2+≥Ca2+≥Sr2+≥Ba2+>>Mg2+>>K+>Na+≈Li+. For all three types of stemwood studied, the affinity orders were almost the same. The ion exchange properties of wood were comparable to those of a weakly acid cation exchanger. The affinity order obtained for the synthetic resin was quite similar to the order given above for wood. The metal sorption properties of wood materials imply that they could be a potential material for removal of metal ions from aqueous solutions.

  20. BIRCH XYLAN GRAFTED WITH PLA BRANCHES OF PREDICTABLE LENGTH

    Directory of Open Access Journals (Sweden)

    Johanna Persson,

    2012-06-01

    Full Text Available Birch xylan (4-O-methylglucuronoxylan isolated from a kraft cooking liquor was delignified and grafted with polylactide of predictable branch length. This graft copolymerization resulted in very high total yields, greater than 90%, and with less than 10% polylactide homopolymer byproducts. Mild reaction conditions (40°C, 5 to 120 minutes were used, which was believed to limit transesterification reactions and thus make it possible to reach good predictability of the polylactide branch length. The thermal properties of the polylactide-grafted xylan depended on the branch length. Short branches resulted in fully amorphous materials with a glass transition temperature of about 48 to 55°C, whereas long polylactide branches resulted in semi-crystalline materials with melting points of about 130°C. Using mixtures of L-lactide and D/L-lactide in the monomer feed further altered the thermal properties. The degradation temperatures of the polylactide-grafted xylans were higher than that of the unmodified xylan, with degradation temperatures of about 300°C and 250°C, respectively. Tensile testing showed increased elongation at break with increasing branch length. The proposed method thus enables tailor-making of copolymers with specific thermal and mechanical properties.

  1. BURSTING POLLEN is required to organize the pollen germination plaque and pollen tube tip in Arabidopsis thaliana.

    Science.gov (United States)

    Hoedemaekers, Karin; Derksen, Jan; Hoogstrate, Suzanne W; Wolters-Arts, Mieke; Oh, Sung-Aeong; Twell, David; Mariani, Celestina; Rieu, Ivo

    2015-04-01

    Pollen germination may occur via the so-called germination pores or directly through the pollen wall at the site of contact with the stigma. In this study, we addressed what processes take place during pollen hydration (i.e. before tube emergence), in a species with extra-poral pollen germination, Arabidopsis thaliana. A T-DNA mutant population was screened by segregation distortion analysis. Histological and electron microscopy techniques were applied to examine the wild-type and mutant phenotypes. Within 1 h of the start of pollen hydration, an intine-like structure consisting of cellulose, callose and at least partly de-esterified pectin was formed at the pollen wall. Subsequently, this 'germination plaque' gradually extended and opened up to provide passage for the cytoplasm into the emerging pollen tube. BURSTING POLLEN (BUP) was identified as a gene essential for the correct organization of this plaque and the tip of the pollen tube. BUP encodes a novel Golgi-located glycosyltransferase related to the glycosyltransferase 4 (GT4) subfamily which is conserved throughout the plant kingdom. Extra-poral pollen germination involves the development of a germination plaque and BUP defines the correct plastic-elastic properties of this plaque and the pollen tube tip by affecting pectin synthesis or delivery.

  2. Seasonal variations of airborne pollen in Allahabad, India.

    Science.gov (United States)

    Sahney, Manju; Chaurasia, Swati

    2008-01-01

    Using a Burkard 7-day volumetric sampler a survey of airborne pollen grains in Allahabad was carried out from December 2004--November 2005 to assess the qualitative and quantitative occurrence of pollen grains during different months of the year, and to characterize the pollen seasons of dominant pollen types in the atmosphere of Allahabad. 80 pollen types were identified out of the total pollen catch of 3,416.34 pollen grains/m(3). Bulk of the pollen originated from anemophilous trees and grasses. Thirteen pollen types recorded more than 1 % of the annual total pollen catch. Holoptelea integrifolia formed the major component of the pollen spectrum constituting 46.21 % of the total pollen catch followed by Poaceae, Azadirachta indica, Ailanthus excelsa, Putranjiva roxburghii, Parthenium hysterophorus, Ricinus communis, Brassica compestris, Amaranthaceae/Chenopodiaceae, Madhuca longifolia, Syzygium cumini, other Asteraceae and Aegle marmelos. Highest pollen counts were obtained in the month of March and lowest in July. The pollen types recorded marked the seasonal pattern of occurrence in the atmosphere. February-May was the principal pollen season with maximum number of pollen counts and pollen types. Chief sources of pollen during this period were arboreal taxa. September-October was the second pollen season with grasses being the main source of pollen. Airborne pollen spectrum reflected the vegetation of Allahabad, except for Alnus sp., which grows in the Himalayan region. A significant negative correlation was found of daily pollen counts with minimum temperature, relative humidity and rainfall.

  3. Airborne Pollen Grains Of Afyon, Turkey

    Institute of Scientific and Technical Information of China (English)

    Adem BICAKCI; Süheyla ERGUN; Sevcan TATLIDIL; Hulusi MALYER; Sabri OZYURT; Ahmet AKKAYA; Nihat SAPAN

    2002-01-01

    The airborne pollen grains of Afyon have been studied for a two-year period (1999-2000) with a Durham sampler. A total of 14 367 pollen grains belonging to 40 taxa have been identified and recorded with some unidentified ones. Of them, 6 732 were identified in 1999 and 7 635 in 2000. Of the total pollen grains, 69.67% were arboreal, 26.64% non-arboreal and 3.68 % unidentified. The majority of the investigated pollen grains were from Pinus, Gramineae, Cupressaceae, Platanus, Chenopodiaceae/Amaranthaceae, Quercus, Ailanthus, Moraceae, Juglans, Salix, Cedrus and Rosaceae. The highest level of pollen grains was in May.

  4. Ecological and phytopathological status of birch stands on the territory of Krasnoyarsk group of districts

    Directory of Open Access Journals (Sweden)

    A. I. Tatarintsev

    2015-04-01

    Full Text Available According to inspection data, the health and vital status of birch (Betula pendula Roth. stands in Krasnoyarsk group of lands (southern part of Central Siberia were estimated (established as satisfactory in general; about half of birch stands near urbanized areas were weakened. The condition of stands decreased significantly with increased recreation use, the effect of technogenic pollution was negligible. The most valuable (important representatives of pathogenic biota identified on birch trees were infestations of necrotic cancer and rot diseases. In birch stands the bacterial dropsy was found to be widespread (agent of infection – Erwinia multivora Scz.-Parf, occurrence of the disease ranged from a single ill tree up to 10–38 % of the stands. The birch stands in taiga areas were affected to a greater extent than in forest-steppe; there were high yield class stands on moist soils. Prevalence of bacteriosis rose with increasing stand age and density and not dependent on recreation use level. Trees with dropsy are dead in fact or potentially. In taiga birch forests the infection and rot of roots was caused by honey agaric (Armillaria mellea sensu lato, that lead to single or, rarely, group tree drying and the fungus usually eliminated already weakened trees. Wood biomass was destroyed by complex of aphyllophorous Hymenomycetes, their hemiparasitic species caused stem rots that decreased stand marketability and also resulted in rot-realated wind-break accumulation. Occurrence of rot was significantly higher in second growth birch stands, possibly above 20 %; the relationship between rot prevalence and forest assessment was not revealed.

  5. Taraxacum officinale pollen depresses seed set of montane wildflowers through pollen allelopathy

    Directory of Open Access Journals (Sweden)

    Deirdre Loughnan

    2014-08-01

    Full Text Available Plant species that share pollinators can suffer from interspecific pollen deposition. Male reproductive success is inevitably reduced by the loss of pollen to flowers of another species. Female reproductive success can be affected by reduced stigmatic area or, more strongly, through allelopathic effects by which the admixture of some foreign pollen reduces seed or fruit set. We tested for allelopathic effects of Taraxacum officinale (Asteracaeae pollen on the seed set of montane wildflowers Erythronium grandiflorum (Liliaceae and Erysimum capitatum (Brassicaceae, by hand-pollinating plants with pollen mixtures. Taraxacum is a common invasive species, which produces allelopathic chemicals in its root and vegetative tissue, making it a likely candidate for pollen allelopathy. Flowers of both species produced fewer well-developed seeds when pollinated with pollen mixtures containing Taraxacum pollen. The pollen-allelopathic potential of weedy dandelion may add to its ability to disrupt communities that it invades.

  6. Pollen resistance to water in 80 angiosperm species: flower structures protect rain-susceptible pollen.

    Science.gov (United States)

    Mao, Yun-Yun; Huang, Shuang-Quan

    2009-08-01

    Flowers exhibit adaptive responses to biotic and abiotic factors. It remains unclear whether pollen susceptibility to rain damage plays a role in the evolution of floral form. We investigated flower performance in rain and compared pollen longevity in dry conditions, pure water and solutions with different sucrose concentrations in 80 flowering species from 46 families with diverse floral shapes and pollination modes. A pollen viability test showed that pollen longevity in all studied species was greatly reduced by wetting. We found that pollen of species with complete protection by flower structures was susceptible to water damage and a high proportion of resistant pollen occurred in unprotected species. Flowers whose structures expose pollen to rain may also reduce rain damage through temporal patterns of pollen presentation. This prediction was supported by our direct measurement of pollen presentation duration on rainy days. Our observations showed that variation in pollen performance in water was associated with differences in floral forms. Water-resistant pollen and extended pollen presentation duration were favored by selection via rain contact in species in which pollen was not protected from rain. These findings support the functional hypothesis that flower structures protect susceptible pollen from rain, demonstrating that rain acts as a force shaping floral form.

  7. Structural analysis of heat-treated birch (Betule papyrifera) surface during artificial weathering

    Energy Technology Data Exchange (ETDEWEB)

    Huang Xianai [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Kocaefe, Duygu, E-mail: dkocaefe@uqac.ca [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Kocaefe, Yasar [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Boluk, Yaman [University of Alberta, 3-142 Markin/CNRL Natural Resources Engineering Facility, Edmonton, Alberta, T6G 2W2 (Canada); Krause, Cornelia [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Investigate detailed structural changes of heat-treated wood due to weathering. Black-Right-Pointing-Pointer Identify connection between physical structural changes and chemical degradation. Black-Right-Pointing-Pointer Study effect of heat treatment conditions on weathering degradation process. - Abstract: Effect of artificial weathering on the surface structural changes of birch (Betule papyrifera) wood, heat-treated to different temperatures, was studied using the fluorescence microscopy and the scanning electron microscopy (SEM). Changes in the chemical structure of wood components were analyzed by FTIR in order to understand the mechanism of degradation taking place due to heat treatment and artificial weathering. The results are compared with those of the untreated (kiln-dried) birch. The SEM analysis results show that the effect of weathering on the cell wall of the untreated birch surface is more than that of heat-treated samples. The FTIR spectroscopy results indicate that lignin is the most sensitive component of heat-treated birch to the weathering degradation process. Elimination of the amorphous and highly crystallised cellulose is observed for both heat-treated and untreated wood during weathering. It is also observed that heat treatment increases the lignin and crystallised cellulose contents, which to some extent protects heat-treated birch against degradation due to weathering.

  8. Differential response of aspen and birch trees to heat stress under elevated carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Darbah, Joseph N.T., E-mail: darbah@ohio.ed [School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931 (United States); Department of Environmental and Plant Biology, Ohio University, 315 Porter Hall, Athens, OH 45701 (United States); Sharkey, Thomas D. [Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824 (United States); Calfapietra, Carlo [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR), Via Salaria km 29300, 00016 Monterotondo Scalo, Roma (Italy); Karnosky, David F. [School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931 (United States)

    2010-04-15

    The effect of high temperature on photosynthesis of isoprene-emitting (aspen) and non-isoprene-emitting (birch) trees were measured under elevated CO{sub 2} and ambient conditions. Aspen trees tolerated heat better than birch trees and elevated CO{sub 2} protected photosynthesis of both species against moderate heat stress. Elevated CO{sub 2} increased carboxylation capacity, photosynthetic electron transport capacity, and triose phosphate use in both birch and aspen trees. High temperature (36-39 deg. C) decreased all of these parameters in birch regardless of CO{sub 2} treatment, but only photosynthetic electron transport and triose phosphate use at ambient CO{sub 2} were reduced in aspen. Among the two aspen clones tested, 271 showed higher thermotolerance than 42E possibly because of the higher isoprene-emission, especially under elevated CO{sub 2}. Our results indicate that isoprene-emitting trees may have a competitive advantage over non-isoprene emitting ones as temperatures rise, indicating that biological diversity may be affected in some ecosystems because of heat tolerance mechanisms. - We report that elevated CO{sub 2} confers increased thermotolerance on both aspen and birch trees while isoprene production in aspen confers further thermotolerance in aspen.

  9. Structural analysis of heat-treated birch (Betule papyrifera) surface during artificial weathering

    Science.gov (United States)

    Huang, Xianai; Kocaefe, Duygu; Kocaefe, Yasar; Boluk, Yaman; Krause, Cornélia

    2013-01-01

    Effect of artificial weathering on the surface structural changes of birch (Betule papyrifera) wood, heat-treated to different temperatures, was studied using the fluorescence microscopy and the scanning electron microscopy (SEM). Changes in the chemical structure of wood components were analyzed by FTIR in order to understand the mechanism of degradation taking place due to heat treatment and artificial weathering. The results are compared with those of the untreated (kiln-dried) birch. The SEM analysis results show that the effect of weathering on the cell wall of the untreated birch surface is more than that of heat-treated samples. The FTIR spectroscopy results indicate that lignin is the most sensitive component of heat-treated birch to the weathering degradation process. Elimination of the amorphous and highly crystallised cellulose is observed for both heat-treated and untreated wood during weathering. It is also observed that heat treatment increases the lignin and crystallised cellulose contents, which to some extent protects heat-treated birch against degradation due to weathering.

  10. Effect of different steam explosion conditions on methane potential and enzymatic saccharification of birch.

    Science.gov (United States)

    Vivekanand, Vivekanand; Olsen, Elisabeth F; Eijsink, Vincent G H; Horn, Svein J

    2013-01-01

    Birch (Betula pubescens) was steam exploded at 13 different conditions with temperatures ranging from 170 to 230 °C and residence times ranging from 5 to 15 min. Increasing severity in the pretreatment led to degradation of xylan and formation of pseudo-lignin. The effect of the pretreatments was evaluated by running enzymatic saccharification and anaerobic digestion followed by analysis of sugar and methane yields, respectively. Enzymatically released glucose increased with pretreatment severity up to 220 °C for 10 min and levels of solubilized glucose reached 97% of the theoretical maximum. The highest methane yield (369 mL gVS(-1)) was obtained at a severity factor of 4.5 and this yield was 1.8 times higher than the yield from untreated birch. Enzymatic glucose yields and methane yields were generally correlated. The results indicate that steam-exploded birch can be effectively converted to either glucose or methane.

  11. DNA extraction of birch leaves by improved CTAB method and optimization of its ISSR system

    Institute of Scientific and Technical Information of China (English)

    PAN hua; YANG Chuan-ping; WEI Zhi-gang; JIANG Jing

    2006-01-01

    The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitable not only for genomic DNA extraction of birch but also for that of other plants. The purity of genomic DNA extracted by the multi-times STE-CTAB extraction method is higher than that by one time STE-CTAB method, and it does not need the process of RNase. The factors of influencing ISSR system were explored based on the genomic DNA of birch extracted by the two methods. The optimal conditions for ISSR system were determined as follows: cycles of denaturation for 30 s at 94℃, annealing for 30 s at 51 ℃, extension for 30 s at 72℃, and a final 7 min extension at 72 ℃.

  12. Simultaneous determination of betulin and betulinic acid in white birch bark using RP-HPLC.

    Science.gov (United States)

    Zhao, Guoling; Yan, Weidong; Cao, Dan

    2007-02-19

    A simple procedure is described for the simultaneous extraction and determination of betulin and betulinic acid in white birch bark. The extraction was checked using different solvents: dichloromethane, ethyl acetate, acetone, chloroform, methanol and 95% ethanol (aqueous solution, v/v). It was found 95% ethanol was a good extraction solvent that allowed extraction of triterpenoid with a highest content. Separation was achieved on a reversed phase C(18) column with acetonitrile-water 86:14 (v/v). Detection was accomplished with UV detection at lambda=210 nm. Using this method, the bioactive triterpenoid in white birch bark were simultaneously determined. Significant variations in the content of betulin and betulinic acid in white birch bark growing in different locations of China were also observed.

  13. Analysis of aspen-and-birch separated small woods’ vegetation in North Steppe of Ukraine

    Directory of Open Access Journals (Sweden)

    N. M. Nazarenko

    2010-09-01

    Full Text Available Conducted analysis of forest vegetation has allowed selecting and specifying classification and typological units of the aspen-and-birch separated small woods, which have statistically significant difference of ecotopic and coenotic parameters. Those parameters of studied forest ecosystems are characterised. Existence of the lines of hygrogenic and edaphogenic substitution, and succession rows are described. Phytoindication description of ecological factors’ pivotal conditions is presented. Driving factors determining parameters, structure and composition of the aspen-and-birch forest ecosystems are diminishing soil moisture, increasing annual temperatures amplitude and soil acidity.

  14. Pollen transport in the Shiyang River drainage, arid China

    Institute of Scientific and Technical Information of China (English)

    ZHU Yan; XIE Yaowen; CHENG Bo; CHEN Fahu; ZHANG Jiawu

    2003-01-01

    In order to assess the contribution of the pollen transported by wind and fluvial flows to the pollen spectra in Shiyang River drainage, a typical small endorheic drainage in arid lands of northwest China, preliminary studies on modern pollen rain along two transects with 91 surface soil samples, 8 atmospheric samples, 30 modern fluvial flow samples and 50 riverbed mud samples, were carried out. Results show that dispersal agents (air, flowing water) have dissimilareffects on transport of pollen and the structure of pollen spectra. Fluvial flow has a stronger capacity than wind to transport large quantities of pollen overlong distances. Pollen transported by fluvial flow makes a large contribution to the pollen spectra of riverbed alluvial sediments. Paleoenvironmental reconstructions undertaken using pollen spectra from fluvial sediments in arid lands arestrongly influenced by pollen transport. Therefore, the sources, the transportation agents and the depositional condition of pollen should be systematically investigated before pollen assemblages are used to derive the environmental significance in such settings.

  15. Seed set, pollen morphology and pollen surface composition response to heat stress in field pea.

    Science.gov (United States)

    Jiang, Yunfei; Lahlali, Rachid; Karunakaran, Chithra; Kumar, Saroj; Davis, Arthur R; Bueckert, Rosalind A

    2015-11-01

    Pea (Pisum sativum L.) is a major legume crop grown in a semi-arid climate in Western Canada, where heat stress affects pollination, seed set and yield. Seed set and pod growth characteristics, along with in vitro percentage pollen germination, pollen tube growth and pollen surface composition, were measured in two pea cultivars (CDC Golden and CDC Sage) subjected to five maximum temperature regimes ranging from 24 to 36 °C. Heat stress reduced percentage pollen germination, pollen tube length, pod length, seed number per pod, and the seed-ovule ratio. Percentage pollen germination of CDC Sage was greater than CDC Golden at 36 °C. No visible morphological differences in pollen grains or the pollen surface were observed between the heat and control-treated pea. However, pollen wall (intine) thickness increased due to heat stress. Mid-infrared attenuated total reflectance (MIR-ATR) spectra revealed that the chemical composition (lipid, proteins and carbohydrates) of each cultivar's pollen grains responded differently to heat stress. The lipid region of the pollen coat and exine of CDC Sage was more stable compared with CDC Golden at 36 °C. Secondary derivatives of ATR spectra indicated the presence of two lipid types, with different amounts present in pollen grains from each cultivar.

  16. In Vitro Pollen Viability and Pollen Germination in Cherry Laurel (Prunus laurocerasus L.

    Directory of Open Access Journals (Sweden)

    Melekber Sulusoglu

    2014-01-01

    Full Text Available Pollen quality is important for growers and breeders. This study was carried out to determine in vitro pollen viability and pollen germination in seven genotypes of cherry laurel (Prunus laurocerasus L.. Two pollen viability tests, TTC (2,3,5-triphenyl tetrazolium chloride and IKI (iodine potassium iodide, were used. Pollen traits of genotypes were studied using an in vitro medium containing 0%, 5%, 10%, 15%, and 20% sucrose to determine the best sucrose concentrations for germination. In the second step, the germinated pollen was counted 1, 4, 6, 10, 12, 24, and 48 hours later until there was no further germination. The viability rates were different according to genotypes and tests used. The IKI and TTC staining tests and pollen germination had low correlation (r2 = 0.0614 and r2 = 0.0015, resp.. Painted pollen rate was higher and pollen was well-stained with IKI test and pollen viability estimated with TTC staining test was better than that estimated with the IKI staining test. 15% sucrose gave the best germination rates in most of the genotypes. Pollen germination rates were recorded periodically from one hour to 48 hours in 15% sucrose and the results showed that pollen germination rates increased after 6 hours of being placed in culture media.

  17. Pollen and pollen antigen as triggers of asthma—what to measure?

    Science.gov (United States)

    Beggs, Paul J.

    Although it has been recognised for many years that biological particulate matter in the atmospheric environment can trigger symptoms of allergic respiratory diseases such as asthma, the results of studies examining the relationships between pollen counts and the occurrence of such diseases have been inconsistent. In addition to the size of pollen grains as an explanation for such disagreement between studies, their is now a body of literature which has demonstrated that airborne pollen allergen can exist in sub-pollen sizes and out of the "pollen season", and that little correlation can occur between allergen levels and pollen counts. These findings not only explain disagreement between epidemiological studies using pollen counts but may raise doubts over the plausibility of any results from such studies. The paper reviews the results of a selection of epidemiological studies of pollen counts and asthma as well as studies which have documented the existence of pollen-free airborne allergen. It is concluded that future epidemiological studies should measure allergen rather than pollen grain counts, using methods that have been developed specifically for this purpose. Further research is required to determine if the presence of airborne pollen-free allergen is a universal phenomenon in pollens and perhaps in moulds as well.

  18. In vitro pollen viability and pollen germination in cherry laurel (Prunus laurocerasus L.).

    Science.gov (United States)

    Sulusoglu, Melekber; Cavusoglu, Aysun

    2014-01-01

    Pollen quality is important for growers and breeders. This study was carried out to determine in vitro pollen viability and pollen germination in seven genotypes of cherry laurel (Prunus laurocerasus L.). Two pollen viability tests, TTC (2,3,5-triphenyl tetrazolium chloride) and IKI (iodine potassium iodide), were used. Pollen traits of genotypes were studied using an in vitro medium containing 0%, 5%, 10%, 15%, and 20% sucrose to determine the best sucrose concentrations for germination. In the second step, the germinated pollen was counted 1, 4, 6, 10, 12, 24, and 48 hours later until there was no further germination. The viability rates were different according to genotypes and tests used. The IKI and TTC staining tests and pollen germination had low correlation (r(2) = 0.0614 and r(2) = 0.0015, resp.). Painted pollen rate was higher and pollen was well-stained with IKI test and pollen viability estimated with TTC staining test was better than that estimated with the IKI staining test. 15% sucrose gave the best germination rates in most of the genotypes. Pollen germination rates were recorded periodically from one hour to 48 hours in 15% sucrose and the results showed that pollen germination rates increased after 6 hours of being placed in culture media.

  19. Polyamines in Pollen: From Microsporogenesis to Fertilization.

    Science.gov (United States)

    Aloisi, Iris; Cai, Giampiero; Serafini-Fracassini, Donatella; Del Duca, Stefano

    2016-01-01

    The entire pollen life span is driven by polyamine (PA) homeostasis, achieved through fine regulation of their biosynthesis, oxidation, conjugation, compartmentalization, uptake, and release. The critical role of PAs, from microsporogenesis to pollen-pistil interaction during fertilization, is suggested by high and dynamic transcript levels of PA biosynthetic genes, as well as by the activities of the corresponding enzymes. Moreover, exogenous supply of PAs strongly affects pollen maturation and pollen tube elongation. A reduction of endogenous free PAs impacts pollen viability both in the early stages of pollen development and during fertilization. A number of studies have demonstrated that PAs largely function by modulating transcription, by structuring pollen cell wall, by modulating protein (mainly cytoskeletal) assembly as well as by modulating the level of reactive oxygen species. Both free low-molecular weight aliphatic PAs, and PAs conjugated to proteins and hydroxyl-cinnamic acids take part in these complex processes. Here, we review both historical and recent evidence regarding molecular events underlying the role of PAs during pollen development. In the concluding remarks, the outstanding issues and directions for future research that will further clarify our understanding of PA involvement during pollen life are outlined.

  20. Pollen types of the Egyptian species of tribe Lactuceae (subfamily Cichorioideae-Compositae)

    OpenAIRE

    Osman, A.K.E.

    2006-01-01

    Pollen morphology of forty six Egyptian species representing twenty three genera of the tribe Lactuceae was investigated using light and scanning electron microscopy. Seven pollen types were recognized: Geropogon pollen type, Koelpinia pollen type, Lactuca pollen type, Launaea pollen type, Rhagadiolus pollen type, Scolymus pollen type and Scorzonera pollen type. Descriptions, a key, light microscope (LM) and scaning electron microscope (SEM) micrographs of each pollen type are provided.

  1. Carbon and Nitrogen Transformations in Surface Soils Under Ermans Birch and Dark Coniferous Forests

    Institute of Scientific and Technical Information of China (English)

    DENG Xiao-Wen; HAN Shi-Jie; HU Yan-Ling; ZHOU Yu-Mei

    2009-01-01

    Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slopc of Changbai Mountains of Northeast China,to compare soil carbon (C) and nitrogen (N) transformations in the two forests.The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy.Soil samples were incubated aerobically at 20 ℃ and field capacity of 700 g kg-1 over a period of 27 weeks.The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest (P<0.05),whereas the cumulative C mineralization (as CO2 emission) in the dark coniferous forest exceeded that in the Ermans birch (P<0.05).Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest (P<0.05).The results suggested that differences of forest types could result in considerable change in soil C and N transformations.

  2. Study of the betulin enriched birch bark extracts effects on human carcinoma cells and ear inflammation

    Directory of Open Access Journals (Sweden)

    Dehelean Cristina A

    2012-11-01

    Full Text Available Abstract Background Pentacyclic triterpenes, mainly betulin and betulinic acid, are valuable anticancer agents found in the bark of birch tree. This study evaluates birch bark extracts for the active principles composition. Results New improved extraction methods were applied on the bark of Betula pendula in order to reach the maximum content in active principles. Extracts were analyzed by HPLC-MS, Raman, SERS and 13C NMR spectroscopy which revealed a very high yield of betulin (over 90%. Growth inhibiting effects were measured in vitro on four malignant human cell lines: A431 (skin epidermoid carcinoma, A2780 (ovarian carcinoma, HeLa (cervix adenocarcinoma and MCF7 (breast adenocarcinoma, by means of MTT assay. All of the prepared bark extracts exerted a pronounced antiproliferative effect against human cancer cell lines. In vivo studies involved the anti-inflammatory effect of birch extracts on TPA-induced model of inflammation in mice. Conclusions The research revealed the efficacy of the extraction procedures as well as the antiproliferative and anti-inflammatory effects of birch extracts.

  3. Synthesis and characterization of birch wood xylan succinoylated in 1-n-butyl-3-methylimidazolium chloride

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Plackett, David

    2011-01-01

    The chemical modification of birch wood xylan was undertaken in the ionic liquid 1-n-butyl-3-methylimidazolium chloride (C4mimCl) using three different long-chain succinic anhydrides: n-octenyl succinic anhydride (n-OSA), n-dodecenyl succinic anhydride (n-DDSA) and n-octadecenyl succinic anhydrid...

  4. Differential response of aspen and birch trees to heat stress under elevated carbon dioxide.

    Science.gov (United States)

    Darbah, Joseph N T; Sharkey, Thomas D; Calfapietra, Carlo; Karnosky, David F

    2010-04-01

    The effect of high temperature on photosynthesis of isoprene-emitting (aspen) and non-isoprene-emitting (birch) trees were measured under elevated CO(2) and ambient conditions. Aspen trees tolerated heat better than birch trees and elevated CO(2) protected photosynthesis of both species against moderate heat stress. Elevated CO(2) increased carboxylation capacity, photosynthetic electron transport capacity, and triose phosphate use in both birch and aspen trees. High temperature (36-39 degrees C) decreased all of these parameters in birch regardless of CO(2) treatment, but only photosynthetic electron transport and triose phosphate use at ambient CO(2) were reduced in aspen. Among the two aspen clones tested, 271 showed higher thermotolerance than 42E possibly because of the higher isoprene-emission, especially under elevated CO(2). Our results indicate that isoprene-emitting trees may have a competitive advantage over non-isoprene emitting ones as temperatures rise, indicating that biological diversity may be affected in some ecosystems because of heat tolerance mechanisms.

  5. Antioxidants from slow pyrolysis bio-oil of birch wood: Application for biodiesel and biobased lubricants

    Science.gov (United States)

    Birch wood was slowly pyrolyzed to produce bio-oil and biochar. Slow pyrolysis conditions including reaction temperature, residence time, and particle size of the feed were optimized to maximize bio-oil yield. Particle size had an insignificant effect, whereas yields of up to 56% were achieved using...

  6. A Review of the Effects of Major Atmospheric Pollutants on Pollen Grains, Pollen Content, and Allergenicity

    Directory of Open Access Journals (Sweden)

    Hélène Sénéchal

    2015-01-01

    Full Text Available This review summarizes the available data related to the effects of air pollution on pollen grains from different plant species. Several studies carried out either on in situ harvested pollen or on pollen exposed in different places more or less polluted are presented and discussed. The different experimental procedures used to monitor the impact of pollution on pollen grains and on various produced external or internal subparticles are listed. Physicochemical and biological effects of artificial pollution (gaseous and particulate on pollen from different plants, in different laboratory conditions, are considered. The effects of polluted pollen grains, subparticles, and derived aeroallergens in animal models, in in vitro cell culture, on healthy human and allergic patients are described. Combined effects of atmospheric pollutants and pollen grains-derived biological material on allergic population are specifically discussed. Within the notion of “polluen,” some methodological biases are underlined and research tracks in this field are proposed.

  7. A Review of the Effects of Major Atmospheric Pollutants on Pollen Grains, Pollen Content, and Allergenicity

    Science.gov (United States)

    Sénéchal, Hélène; Visez, Nicolas; Charpin, Denis; Shahali, Youcef; Peltre, Gabriel; Biolley, Jean-Philippe; Lhuissier, Franck; Couderc, Rémy; Yamada, Ohri; Malrat-Domenge, Audrey; Pham-Thi, Nhân; Poncet, Pascal; Sutra, Jean-Pierre

    2015-01-01

    This review summarizes the available data related to the effects of air pollution on pollen grains from different plant species. Several studies carried out either on in situ harvested pollen or on pollen exposed in different places more or less polluted are presented and discussed. The different experimental procedures used to monitor the impact of pollution on pollen grains and on various produced external or internal subparticles are listed. Physicochemical and biological effects of artificial pollution (gaseous and particulate) on pollen from different plants, in different laboratory conditions, are considered. The effects of polluted pollen grains, subparticles, and derived aeroallergens in animal models, in in vitro cell culture, on healthy human and allergic patients are described. Combined effects of atmospheric pollutants and pollen grains-derived biological material on allergic population are specifically discussed. Within the notion of “polluen,” some methodological biases are underlined and research tracks in this field are proposed. PMID:26819967

  8. Impacts of Elevated Atmospheric CO2 and O3 on Paper Birch (Betula papyrifera: Reproductive Fitness

    Directory of Open Access Journals (Sweden)

    Joseph N. T. Darbah

    2007-01-01

    Full Text Available Atmospheric CO2 and tropospheric O3 are rising in many regions of the world. Little is known about how these two commonly co-occurring gases will affect reproductive fitness of important forest tree species. Here, we report on the long-term effects of CO3 and O3 for paper birch seedlings exposed for nearly their entire life history at the Aspen FACE (Free Air Carbon Dioxide Enrichment site in Rhinelander, WI. Elevated CO2 increased both male and female flower production, while elevated O3 increased female flower production compared to trees in control rings. Interestingly, very little flowering has yet occurred in combined treatment. Elevated CO2 had significant positive effect on birch catkin size, weight, and germination success rate (elevated CO2 increased germination rate of birch by 110% compared to ambient CO2 concentrations, decreased seedling mortality by 73%, increased seed weight by 17%, increased root length by 59%, and root-to-shoot ratio was significantly decreased, all at 3 weeks after germination, while the opposite was true of elevated O3 (elevated O3 decreased the germination rate of birch by 62%, decreased seed weight by 25%, and increased root length by 15%. Under elevated CO2, plant dry mass increased by 9 and 78% at the end of 3 and 14 weeks, respectively. Also, the root and shoot lengths, as well as the biomass of the seedlings, were increased for seeds produced under elevated CO2, while the reverse was true for seedlings from seeds produced under the elevated O3. Similar trends in treatment differences were observed in seed characteristics, germination, and seedling development for seeds collected in both 2004 and 2005. Our results suggest that elevated CO2 and O3 can dramatically affect flowering, seed production, and seed quality of paper birch, affecting reproductive fitness of this species.

  9. Reference: POLLEN1LELAT52 [PLACE

    Lifescience Database Archive (English)

    Full Text Available POLLEN1LELAT52 Bate N, Twell D Functional architecture of a late pollen promoter: polle...n-specific transcription is developmentally regulated by multiple stage-specific and co-dependent activator elements Plant Mol Biol 37:859-869 (1998) PubMed: 9678581; ...

  10. Reference: POLLEN1LELAT52 [PLACE

    Lifescience Database Archive (English)

    Full Text Available POLLEN1LELAT52 Filichkin SA, Leonard JM, Monteros A, Liu PP, Nonogaki H. A novel en...do-beta-mannanase gene in tomato LeMAN5 is associated with anther and pollen development. Plant Physiol. 134 1080-1087 (2004) PubMed: 14976239 ...

  11. Reference: POLLEN2LELAT52 [PLACE

    Lifescience Database Archive (English)

    Full Text Available POLLEN2LELAT52 Bate N, Twell D Functional architecture of a late pollen promoter: polle...n-specific transcription is developmentally regulated by multiple stage-specific and co-dependent activator elements Plant Mol Biol 37:859-869 (1998) PubMed: 9678581; ...

  12. Polyamines in Pollen: From Microsporogenesis to Fertilization

    Science.gov (United States)

    Aloisi, Iris; Cai, Giampiero; Serafini-Fracassini, Donatella; Del Duca, Stefano

    2016-01-01

    The entire pollen life span is driven by polyamine (PA) homeostasis, achieved through fine regulation of their biosynthesis, oxidation, conjugation, compartmentalization, uptake, and release. The critical role of PAs, from microsporogenesis to pollen–pistil interaction during fertilization, is suggested by high and dynamic transcript levels of PA biosynthetic genes, as well as by the activities of the corresponding enzymes. Moreover, exogenous supply of PAs strongly affects pollen maturation and pollen tube elongation. A reduction of endogenous free PAs impacts pollen viability both in the early stages of pollen development and during fertilization. A number of studies have demonstrated that PAs largely function by modulating transcription, by structuring pollen cell wall, by modulating protein (mainly cytoskeletal) assembly as well as by modulating the level of reactive oxygen species. Both free low-molecular weight aliphatic PAs, and PAs conjugated to proteins and hydroxyl-cinnamic acids take part in these complex processes. Here, we review both historical and recent evidence regarding molecular events underlying the role of PAs during pollen development. In the concluding remarks, the outstanding issues and directions for future research that will further clarify our understanding of PA involvement during pollen life are outlined. PMID:26925074

  13. Storage and Viability of Hedychium Pollen

    Science.gov (United States)

    Hedychium species generally flower in the summer and fall, but some bloom in winter and spring times. The different flowering times of the species implies that there is a need to find a way for storing and conserving viable pollen. The maintenance of pollen viability depends on several factors, incl...

  14. Pollen viability and membrane lipid composition.

    NARCIS (Netherlands)

    Bilsen, van D.G.J.L.

    1993-01-01

    In this thesis membrane lipid composition is studied in relation to pollen viability during storage. Chapter 1 reviews pollen viability, membranes in the dry state and membrane changes associated with cellular aging. This chapter is followed by a study of age-related changes in phospholipid composit

  15. Preservation of cycad and Ginkgo pollen

    Science.gov (United States)

    Frederiksen, N.O.

    1978-01-01

    Pollen grains of Ginkgo, Cycas, and Encephalartos were chemically treated together with pollen of Quercus, Alnus, and Pinus, the latter three genera being used as standards. The experiments showed that: (1) boiling the pollen for 8-10 hours in 10% KOH had little if any effect on any of the grains; (2) lengthy acetolysis treatment produced some degradation or corrosion, particularly in Ginkgo and Cycas, but the grains of even these genera remained easily recognizable; (3) oxidation with KMnO4 followed by H2O2 showed that pollen of Ginkgo, Cycas, and Encephalartos remains better preserved than that of Quercus and Alnus, and although Ginkgo and Encephalartos probably are slightly less resistant to oxidation than Pinus, no great differences exists between these monosulcate types and Pinus. Thus the experiments show that, at least for sediments low in bacteria, cycad and Ginkgo pollen should be well represented in the fossil record as far as their preservational capabilities are concerned. ?? 1978.

  16. New insights into ragweed pollen allergens.

    Science.gov (United States)

    Bordas-Le Floch, Véronique; Groeme, Rachel; Chabre, Henri; Baron-Bodo, Véronique; Nony, Emmanuel; Mascarell, Laurent; Moingeon, Philippe

    2015-11-01

    Pollen allergens from short ragweed (Ambrosia artemisiifolia) cause severe respiratory allergies in North America and Europe. To date, ten short ragweed pollen allergens belonging to eight protein families, including the recently discovered novel major allergen Amb a 11, have been recorded in the International Union of Immunological Societies (IUIS) allergen database. With evidence that other components may further contribute to short ragweed pollen allergenicity, a better understanding of the allergen repertoire is a requisite for the design of proper diagnostic tools and efficient immunotherapies. This review provides an update on both known as well as novel candidate allergens from short ragweed pollen, identified through a comprehensive characterization of the ragweed pollen transcriptome and proteome.

  17. Immunoproteomic tools are used to identify masked allergens: Ole e 12, an allergenic isoflavone reductase from olive (Olea europaea) pollen.

    Science.gov (United States)

    Castro, Lourdes; Crespo, Jesús F; Rodríguez, Julia; Rodríguez, Rosalía; Villalba, Mayte

    2015-12-01

    Proteins performing important biochemical activities in the olive tree (Olea europaea) pollen have been identified as allergens. One novel 37-kDa protein seems to be associated to the IgE-binding profile of a group of patients suffering allergy to peach and olive pollen. Three previously described olive pollen allergens exhibit very similar molecular mass. Our objective was to identify this allergen by using immunoproteomic approaches. After 2D-electrophoresis and mass spectrometry, peptide sequences from several IgE-binding spots, allowed identifying this new allergen, as well as cloning and DNA sequencing of the corresponding gene. The allergen, named Ole e 12, is a polymorphic isoflavone reductase-like protein of 308 amino acids showing 80% and 74% identity with birch and pear allergens, Bet v 6 and Pyr c 5, respectively. A prevalence of 33% in the selected population is in contrast to 4%-10% in groups of subjects suffering from pollinosis. Recombinant allergen was produced in Escherichia coli, and deeply characterised. Immunoblotting and ELISA detection as well as inhibition experiments were performed with polyclonal antisera and allergic patients' sera. The recombinant allergen retains the IgE reactivity of its natural counterpart. Close structural and immunological relationships between members of this protein family were supported by their IgG recognition in vegetable species. In summary, Ole e 12 is a minor olive pollen allergen, which gains relevance in patients allergic to peach with olive pollinosis. Proteomic approaches used to analyse this allergen provide useful tools to identify hidden allergens, relevant for several allergic populations and thus complete allergenic panels.

  18. Pollen competition between two sympatric Orchis species (Orchidaceae): the overtaking of conspecific of heterospecific pollen as a reproductive barrier.

    Science.gov (United States)

    Luca, A; Palermo, A M; Bellusci, F; Pellegrino, G

    2015-01-01

    The frequency of hybrid formation in angiosperms depends on how and when heterospecific pollen is transferred to the stigma, and on the success of that heterospecific pollen at fertilising ovules. We applied pollen mixtures to stigmas to determine how pollen interactions affect siring success and the frequency of hybrid formation between two species of Mediterranean deceptive orchid. Plants of Orchis italica and O. anthropophora were pollinated with conspecific and heterospecific pollen (first conspecific pollen then heterospecific pollen and vice versa) and molecular analysis was used to check the paternity of the seeds produced. In this pair of Mediterranean orchids, competition between conspecific and heterospecific pollen functions as a post-pollination pre-zygotic barrier limiting the frequency of the formation of hybrids in nature. Flowers pollinated with heterospecific pollen can remain receptive for the arrival of conspecific pollen for a long time. There is always an advantage of conspecific pollen for fruit formation, whether it comes before or after heterospecific pollen, because it overtakes the heterospecific pollen. The conspecific pollen advantage exhibited in O. italica and O. anthropophora is likely to result from the reduced germination of heterospecific pollen or retarded growth of heterospecific pollen tubes in the stigma and ovary. Overall, the results indicate that our hybrid zone represents a phenomenon of little evolutionary consequence, and the conspecific pollen advantage maintains the genetic integrity of the parental species.

  19. Symmetric pollen mitosis I and suppression of pollen mitosis II prevent pollen development in Brachiaria jubata (Gramineae

    Directory of Open Access Journals (Sweden)

    C. Risso-Pascotto

    2005-11-01

    Full Text Available Microsporogenesis and pollen development were analyzed in a tetraploid (2n = 4x = 36 accession of the forage grass Brachiaria jubata (BRA 007820 from the Embrapa Beef Cattle Brachiaria collection that showed partial male sterility. Microsporocytes and pollen grains were prepared by squashing and staining with 0.5% propionic carmine. The meiotic process was typical of polyploids, with precocious chromosome migration to the poles and laggards in both meiosis I and II, resulting in tetrads with micronuclei in some microspores. After callose dissolution, microspores were released into the anther locule and appeared to be normal. Although each microspore initiated its differentiation into a pollen grain, in 11.1% of them nucleus polarization was not observed, i.e., pollen mitosis I was symmetric and the typical hemispherical cell plate was not detected. After a central cytokinesis, two equal-sized cells showing equal chromatin condensation and the same nuclear shape and size were formed. Generative cells and vegetative cells could not be distinguished. These cells did not undergo the second pollen mitosis and after completion of pollen wall synthesis each gave rise to a sterile and uninucleate pollen grain. The frequency of abnormal pollen mitosis varied among flowers and also among inflorescences. All plants were equally affected. The absence of fertile sperm cells in a considerable amount of pollen grains in this accession of B. jubata may compromise its use in breeding and could explain, at least in part, why seed production is low when compared with the amount of flowers per raceme.

  20. Pollen dispersal in sugar beet production fields.

    Science.gov (United States)

    Darmency, Henri; Klein, Etienne K; De Garanbé, Thierry Gestat; Gouyon, Pierre-Henri; Richard-Molard, Marc; Muchembled, Claude

    2009-04-01

    Pollen-mediated gene flow has important implications for biodiversity conservation and for breeders and farmers' activities. In sugar beet production fields, a few sugar beet bolters can produce pollen as well as be fertilized by wild and weed beet. Since the crop, the wild beets, and the weed beets are the same species and intercross freely, the question of pollen flow is an important issue to determine the potential dispersal of transgenes from field to field and to wild habitats. We report here an experiment to describe pollen dispersal from a small herbicide-resistant sugar beet source towards male sterile target plants located along radiating lines up to 1,200 m away. Individual dispersal functions were inferred from statistical analyses and compared. Pollen limitation, as expected in root-production fields, was confirmed at all the distances from the pollen source. The number of resistant seeds produced by bait plants best fitted a fat-tailed probability distribution curve of pollen grains (power-law) dependent on the distance from the pollen source. A literature survey confirmed that power-law function could fit in most cases. The b coefficient was lower than 2. The number of fertilized flowers by background (herbicide-susceptible) pollen grains was uniform across the whole field. Airborne pollen had a fertilization impact equivalent to that of one adjacent bolter. The individual dispersal function from different pollen sources can be integrated to provide the pollen cloud composition for a given target plant, thus allowing modeling of gene flow in a field, inter-fields in a small region, and also in seed-production area. Long-distance pollen flow is not negligible and could play an important role in rapid transgene dispersal from crop to wild and weed beets in the landscape. The removing of any bolting, herbicide-resistant sugar beet should be compulsory to prevent the occurrence of herbicide-resistant weed beet, thus preventing gene flow to wild

  1. Alnus as a disturbing factor in pollen diagrams

    NARCIS (Netherlands)

    Janssen, C.R.

    1959-01-01

    It is commonly accepted that percentages of pollen in a pollen diagram do not express the exact composition of forests in earlier times. This inaccuracy is due to several factors, for instance the different quantities of pollen produced by plants, the distance of transport etc. A pollen diagram tell

  2. Development of SSR Markers and Genetic Diversity in White Birch (Betula platyphylla.

    Directory of Open Access Journals (Sweden)

    Wei Hao

    Full Text Available In order to study genetic diversity of white birch (Betula platyphylla, 544 primer pairs were designed based on the genome-wide Solexa sequences. Among them, 215 primer pairs showed polymorphism between five genotypes and 111 primer pairs that presented clear visible bands in genotyping 41 white birch plants that were collected from 6 different geographical regions. A total of 717 alleles were obtained at 111 loci with a range of 2 to 12 alleles per locus. The results of statistic analysis showed that polymorphic frequency of the alleles ranged from 17% to 100% with a mean of 55.85%; polymorphism information content (PIC of the loci was from 0.09 to 0.58 with a mean of 0.30; and gene diversity between the tested genotypes was from 0.01 to 0.66 with a mean of 0.36. The results also indicated that major allele frequency ranged from 0.39 to 1.00 with an mean of 0.75; expected heterozygosity from 0.22 to 0.54 with a mean of 0.46; observed heterozygosity from 0.02 to 0.95 with a mean of 0.26; Nei's index from 0.21 to 0.54 with a mean of 0.46; and Shannon's Information from 0.26 to 0.87 with a mean of 0.66. The 41 white birch genotypes at the 111 selected SSR loci showed low to moderate similarity (0.025-0.610, indicating complicated genetic diversity among the white birch collections. The UPGMA-based clustering analysis of the allelic constitution of 41 white birch genotypes at 111 SSR loci suggested that the six different geographical regions can be further separated into four clusters at a similarity coefficient of 0.22. Genotypes from Huanren and Liangshui provenances were grouped into Cluster I, genotypes from Xiaobeihu and Qingyuan provenances into Cluster II, genotypes from Finland provenance into Cluster III, and genotypes from Maoershan into Cluster IV. The information provided in this study could help for genetic improvement and germplasm conservation, evaluation and utilization in white birch tree breeding program.

  3. A combinatorial morphospace for angiosperm pollen

    Science.gov (United States)

    Mander, Luke

    2016-04-01

    The morphology of angiosperm (flowering plant) pollen is extraordinarily diverse. This diversity results from variations in the morphology of discrete anatomical components. These components include the overall shape of a pollen grain, the stratification of the exine, the number and form of any apertures, the type of dispersal unit, and the nature of any surface ornamentation. Different angiosperm pollen morphotypes reflect different combinations of these discrete components. In this talk, I ask the following question: given the anatomical components of angiosperm pollen that are known to exist in the plant kingdom, how many unique biologically plausible combinations of these components are there? I explore this question from the perspective of enumerative combinatorics using an algorithm I have written in the Python programming language. This algorithm (1) calculates the number of combinations of these components; (2) enumerates those combinations; and (3) graphically displays those combinations. The result is a combinatorial morphospace that reflects an underlying notion that the process of morphogenesis in angiosperm pollen can be thought of as an n choose k counting problem. I compare the morphology of extant and fossil angiosperm pollen grains to this morphospace, and suggest that from a combinatorial point of view angiosperm pollen is not as diverse as it could be, which may be a result of developmental constraints.

  4. Pollen

    Science.gov (United States)

    ... most common grasses that can cause allergies are: Bermuda grass Johnson grass Kentucky bluegrass Orchard grass Sweet ... Health Sciences 111 T.W. Alexander Drive Research Triangle Park, N.C. 27709 NIEHS Staff: Request an ...

  5. Variation in Pollen-Donor Composition among Pollinators in an Entomophilous Tree Species, Castanea crenata, Revealed by Single-Pollen Genotyping

    OpenAIRE

    Yoichi Hasegawa; Yoshihisa Suyama; Kenji Seiwa

    2015-01-01

    Background In plants, reproductive success is largely determined by the composition of pollen (i.e., self-pollen and outcross-pollen from near and distant pollen-donors) transported as a result of pollinator foraging behavior (e.g., pollen carryover). However, little evidence is available on how and to what extent the pollen carryover affects the pollen-donor composition and on which insect taxa are effective outcross-pollen transporters under field conditions. In this study, we explored role...

  6. Deep-sea pollen research in China

    Institute of Scientific and Technical Information of China (English)

    SUN Xiangjun; LUO Yunli; CHEN Huaicheng

    2003-01-01

    This paper briefly presents the progress of deep-sea pollen research in China since the beginning ofninetieths of the last Century. All the deep-sea pollen contri-butions mainly come from the South China Sea (SCS) andthe East China Sea (ECS). The German-Chinese joint cruise(Sonne 95) and ODP 184 cruise initiated by Chinese scientistsin the SCS provided excellent material for the deep-sea pol-len research. So far a number of pollen results of 20-30 kaand million years from the SCS have been published. A couple of deep-sea pollen records from Okinawa Through of the ECS also came out. The high resolution pollen records obtained from the continuous deposits with high sedimentation rates and reliable age control of the deep-sea sediments provided a high time resolution history (hundred to millennial scales) of vegetation, environment and monsoon evolution of the pollen source areas (southern China and Japan). Spectral analysis of deep-sea pollen records from the SCS discovered orbital (100, 41, 23, 10 ka) and suborbital cyclicities (Heinrich and Dansgaard/Oscheger-O/D events) in the vege-tation changes. Moreover, cross spectral analysis showed that the trend of vegetation changes in northern SCS was regulated mainly by changes of the ice volume in the Northern Hemisphere. The pollen record of the last 20 ka from the Okinawa Through of the ECS indicates that the marine environmental change lagged that on the terrestrail by about 1000 year. The asynchronous environmental changes between land and sea were probably caused by the time difference in thermohaline circulation. This study underscored the role of the deep-sea plant fossils as a bridge across the land and sea.

  7. Pectic arabinan side chains are essential for pollen cell wall integrity during pollen development

    DEFF Research Database (Denmark)

    Cankar, Katarina; Kortstee, Anne; Toonen, Marcel A.J.

    2014-01-01

    transgenes were not transmitted to the next generation when these lines were used as a pollen donor, suggesting male sterility. Viability of mature pollen was severely decreased in potato lines with reduced pectic arabinan, but not in lines with altered galactan side chains. Anthers and pollen of different...... developmental stages were microscopically examined to study the phenotype in more detail. Scanning electron microscopy of flowers showed collapsed pollen grains in mature anthers and in earlier stages cytoplasmic protrusions at the site of the of kin pore, eventually leading to bursting of the pollen grain...... and leaking of the cytoplasm. This phenomenon is only observed after the microspores are released and the tapetum starts to degenerate. Timing of the phenotype indicates a role for pectic arabinan side chains during remodelling of the cell wall when the pollen grain is maturing and dehydrating....

  8. Genomic expression profiling of mature soybean (Glycine max) pollen

    OpenAIRE

    Singh Mohan B; Gresshoff Peter M; Wong Chui E; Bhalla Prem L; Haerizadeh Farzad

    2009-01-01

    Abstract Background Pollen, the male partner in the reproduction of flowering plants, comprises either two or three cells at maturity. The current knowledge of the pollen transcriptome is limited to the model plant systems Arabidopsis thaliana and Oryza sativa which have tri-cellular pollen grains at maturity. Comparative studies on pollen of other genera, particularly crop plants, are needed to understand the pollen gene networks that are subject to functional and evolutionary conservation. ...

  9. Proteomic analyses of apoplastic proteins from germinating Arabidopsis thaliana pollen

    OpenAIRE

    Ge, Weina; Song, Yun; Zhang, Cuijun; Zhang, Yafang; Burlingame, Alma L; Guo, Yi

    2011-01-01

    Pollen grains play important roles in the reproductive processes of flowering plants. The roles of apoplastic proteins in pollen germination and in pollen tube growth are comparatively less well understood. To investigate the functions of apoplastic proteins in pollen germination, the global apoplastic proteins of mature and germinated Arabidopsis thaliana pollen grains were prepared for differential analyses by using 2-dimensional fluorescence difference gel electrophoresis (2-D DIGE) satura...

  10. Effect of Different Pretreatment Methods on Birch Outer Bark: New Biorefinery Routes

    Directory of Open Access Journals (Sweden)

    Anthi Karnaouri

    2016-03-01

    Full Text Available A comparative study among different pretreatment methods used for the fractionation of the birch outer bark components, including steam explosion, hydrothermal and organosolv treatments based on the use of ethanol/water media, is reported. The residual solid fractions have been characterized by ATR-FTIR, 13C-solid-state NMR and morphological alterations after pretreatment were detected by scanning electron microscopy. The general chemical composition of the untreated and treated bark including determination of extractives, suberin, lignin and monosaccharides was also studied. Composition of the residual solid fraction and relative proportions of different components, as a function of the processing conditions, could be established. Organosolv treatment produces a suberin-rich solid fraction, while during hydrothermal and steam explosion treatment cleavage of polysaccharide bonds occurs. This work will provide a deeper fundamental knowledge of the bark chemical composition, thus increasing the utilization efficiency of birch outer bark and may create possibilities to up-scale the fractionation processes.

  11. Proteomic Analysis of Responsive Proteins Induced in Japanese Birch Plantlet Treated with Salicylic Acid

    Science.gov (United States)

    Suzuki, Hiromu; Takashima, Yuya; Ishiguri, Futoshi; Yoshizawa, Nobuo; Yokota, Shinso

    2014-01-01

    The present study was performed to unravel the mechanisms of systemic acquired resistance (SAR) establishment and resistance signaling pathways against the canker-rot fungus (Inonotus obliquus strain IO-U1) infection in Japanese birch plantlet No.8. Modulation of protein-profile induced by salicylic acid (SA)-administration was analyzed, and SA-responsive proteins were identified. In total, 5 specifically expressed, 3 significantly increased, and 3 significantly decreased protein spots were identified using liquid chromatography/tandem mass spectrometry (LC/MS/MS) and the sequence tag method. These proteins were malate dehydrogenase, succinate dehydrogenase, phosphoglycerate kinase, diaminopimalate decarboxylase, arginase, chorismate mutase, cyclophilin, aminopeptidase, and unknown function proteins. These proteins are considered to be involved in SAR-establishment mechanisms in the Japanese birch plantlet No 8.

  12. Properties of plasticized composite films prepared from nanofibrillated cellulose and birch wood xylan

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Blomfeldt, Thomas O. J.; Hedenqvist, Mikael S.

    2012-01-01

    Xylans, an important sub-class of hemicelluloses, represent a largely untapped resource for new renewable materials derived from biomass. As with other carbohydrates, nanocellulose reinforcement of xylans is interesting as a route to new bio-materials. With this in mind, birch wood xylan was comb......Xylans, an important sub-class of hemicelluloses, represent a largely untapped resource for new renewable materials derived from biomass. As with other carbohydrates, nanocellulose reinforcement of xylans is interesting as a route to new bio-materials. With this in mind, birch wood xylan...... was combined with nanofibrillated cellulose (NFC) and films were cast with and without glycerol, sorbitol or methoxypolyethylene glycol (MPEG) as plasticizers. Microscopy revealed some NFC agglomeration in the composite films as well as a layered nanocellulose structure. Equilibrium moisture content...

  13. Proteomic Analysis of Responsive Proteins Induced in Japanese Birch Plantlet Treated with Salicylic Acid

    Directory of Open Access Journals (Sweden)

    Hiromu Suzuki

    2014-07-01

    Full Text Available The present study was performed to unravel the mechanisms of systemic acquired resistance (SAR establishment and resistance signaling pathways against the canker-rot fungus (Inonotus obliquus strain IO-U1 infection in Japanese birch plantlet No.8. Modulation of protein-profile induced by salicylic acid (SA-administration was analyzed, and SA-responsive proteins were identified. In total, 5 specifically expressed, 3 significantly increased, and 3 significantly decreased protein spots were identified using liquid chromatography/tandem mass spectrometry (LC/MS/MS and the sequence tag method. These proteins were malate dehydrogenase, succinate dehydrogenase, phosphoglycerate kinase, diaminopimalate decarboxylase, arginase, chorismate mutase, cyclophilin, aminopeptidase, and unknown function proteins. These proteins are considered to be involved in SAR-establishment mechanisms in the Japanese birch plantlet No 8.

  14. Analysis and identification of SCAR molecular markers associated with birch fiber length trait

    Institute of Scientific and Technical Information of China (English)

    WANG Dan; WEI Zhi-gang; YANG Chuan-ping; LIU Guan-jun

    2008-01-01

    The fiber length trait (FLT) of 538 individuals from nature birch population in Maorshan region,Heilongjang,China were measured,of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA (RAPD) technique.In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors,and a correlative segment BFLR-16 was obtained.The correlation coefficient between BFLI-16 and FLT was 0.6144,with the significant level of 1%.BFLI-16 was then cloned,sequenced and transformed into SCAR marker.The percentage of identifying long fiber birches by this SCAR was more than 92.The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length,and its existence is significantly correlative with the increase in the fiber length.

  15. Influence of Biomass Pretreatment Process Time on Furfural Extraction from Birch Wood

    Science.gov (United States)

    Brazdausks, Prans; Puke, Maris; Vedernikovs, Nikolajs; Kruma, Irena

    2013-12-01

    Furfural is a biomass derived-chemical that can be used to replace petrochemicals. In this study, dilute sulphuric acid hydrolysis was used for hemicelluloses secession from birch wood. The reaction was investigated at different biomass treatment times (10-90 min, increasing it by 10 min). We found that the greatest amount of furfural 1.4-2.6%, which is 9.7-17.7% from theoretical possible yield, was formed in the first 30 min of the beginning of birch wood pentoses monosaccharide dehydration, but the greatest yield of furfural 10.3%, which is 70.0% from the theoretical yield, can be obtained after 90 min. Given that furfural yield generally does not exceed 50% from the theoretical amount, the result can be considered as very good.

  16. Cadmium accumulation and its effect on the in vitro growth of woody fleabane and mycorrhized white birch

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, R.; Bertrand, A.; Casares, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain); Garcia, R. [Departamento de Quimica Fisica y Analitica, Oviedo University, Julian Claveria s/n, 33071 Oviedo (Spain); Gonzalez, A. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)], E-mail: aidag@uniovi.es; Tames, R.S. [Departamento de Biologia de Organismos y Sistemas, Oviedo University, Catedratico Rodrigo Uria s/n, 33071 Oviedo (Spain)

    2008-04-15

    The effect of Cd on woody fleabane (Dittrichia viscosa (L.) Greuter) and white birch (Betula celtiberica Rothm. and Vasc.) was examined. Woody fleabane and white birch were grown in vitro in Murashige, T., Skoog, F., [1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473-479] (MS) plus Cd (10 mg Cd kg{sup -1}) and except for root length in white birch, plant development was inhibited when Cd was added. Cd accumulation in above-ground tissues showed differences among clones, reaching 1300 and 463 mg Cd kg{sup -1} dry wt. in selected clones of woody fleabane and white birch, respectively. Tolerance of Paxillus filamentosus (Scop) Fr. to Cd was also examined before mycorrhization. Plants of mycorrhized white birch grown in the presence of Cd had a better development and accumulated more Cd in their shoots than the non-mycorrhized ones. The use of selected clones of woody fleabane and the mycorrhization of white birch enhance extraction efficiency from contaminated soils in phytoremediation programs. - The high accumulation of Cd observed in selected clones of Dittrichia viscosa and mycorrhized Betula celtiberica grown in vitro implies a potential application for phytoextraction.

  17. The effect of temperature on pollen germination and pollen tube growth of sour cherry cultivars

    Directory of Open Access Journals (Sweden)

    Milatović Dragan P.

    2014-01-01

    Full Text Available The study was carried out to determine the effect of three different temperatures (5, 15 and 25°C on in vitro pollen germination and pollen tube growth of five sour cherry cultivars: ‘Heimanns Konservenweichsel’, ‘Kelleriis 14’, ‘Oblačinska’, ‘Rexelle’ and ‘Šumadinka’. Pollen germination a % agar % Temperature significantly affected pollen germination. High germination rates (50-70% were obtained at both 15°C and 25°C. Satisfactory germination rates (42-51% were also obtained at 5°C in some cultivars (‘Rexelle’, ‘Šumadinka’ and ‘Heimanns Konservenweichsel’. The influence of temperature on the pollen tube growth was more prominent. The length of pollen tubes was three to six times higher at 15°C and 25°C in comparison with 5°C. This has led to the conclusion that the temperature of 5°C, although it could be adequate for pollen germination, is not high enough for optimal pollen tube growth. was determined by germinating pollen grains in culture medium containing 0.7agar-and 15sucrose. [Projekat Ministarstva nauke Republike Srbije, br. TR-31063

  18. Phosphoproteomics Profiling of Tobacco Mature Pollen and Pollen Activated in vitro.

    Science.gov (United States)

    Fíla, Jan; Radau, Sonja; Matros, Andrea; Hartmann, Anja; Scholz, Uwe; Feciková, Jana; Mock, Hans-Peter; Čapková, Věra; Zahedi, René Peiman; Honys, David

    2016-04-01

    Tobacco mature pollen has extremely desiccated cytoplasm, and is metabolically quiescent. Upon re-hydration it becomes metabolically active and that results in later emergence of rapidly growing pollen tube. These changes in cytoplasm hydration and metabolic activity are accompanied by protein phosphorylation. In this study, we subjected mature pollen, 5-min-activated pollen, and 30-min-activated pollen to TCA/acetone protein extraction, trypsin digestion and phosphopeptide enrichment by titanium dioxide. The enriched fraction was subjected to nLC-MS/MS. We identified 471 phosphopeptides that carried 432 phosphorylation sites, position of which was exactly matched by mass spectrometry. These 471 phosphopeptides were assigned to 301 phosphoproteins, because some proteins carried more phosphorylation sites. Of the 13 functional groups, the majority of proteins were put into these categories: transcription, protein synthesis, protein destination and storage, and signal transduction. Many proteins were of unknown function, reflecting the fact that male gametophyte contains many specific proteins that have not been fully functionally annotated. The quantitative data highlighted the dynamics of protein phosphorylation during pollen activation; the identified phosphopeptides were divided into seven groups based on the regulatory trends. The major group comprised mature pollen-specific phosphopeptides that were dephosphorylated during pollen activation. Several phosphopeptides representing the same phosphoprotein had different regulation, which pinpointed the complexity of protein phosphorylation and its clear functional context. Collectively, we showed the first phosphoproteomics data on activated pollen where the position of phosphorylation sites was clearly demonstrated and regulatory kinetics was resolved.

  19. Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The germination of pollen grain in vitro and the growth of pollen tube in the pistil of rice were observed with a microscope.The stigma was removed at different time points after pollination to study its effect on seed setting rate.The rice pollen grain started to germinate at 2 min after pollination and the pollen tube penetrated stigma into style in 5-10 min,30 min later the end of pollen tube reached the bottom of ovary,and only some pollen tubes arrived at embryo sac at 40 min after pollination.Meanwhile,a small amount of catlose began to deposit in the pollen tubes,a great deal of callose was observed at 50 min after pollination,whereas the pollen grain began to shrink.The growing rates of pollen tube in the rice stigma,style and ovary were 1500,5000,and 5400 pm/h,respectively.The seed setting rate was quite low when the stigma was removed at about 10-15 min after pollination,gradually increased when it removed at 20 min to 50 min after pollination,and over 60%when it removed at 50 min after pollination and finally tended to be stable.

  20. Shelf life extension and sensory evaluation of birch tree sap using chemical preservatives

    Directory of Open Access Journals (Sweden)

    Maciej Bilek

    2016-10-01

    Full Text Available The aim of this study was to assess the stability of the birch tree sap, depending on the addition and concentration of two chemical factors, ie. potassium sorbate and acids: malic, citric or lactic. As in our previous studies we found that the optimal physical parameter to assess the stability of birch sap is turbidity measurement, we used turbidimeter for estimate the effectiveness of shelf life extending. Sensory evaluation was carried out by university sensory panel with 8 skilled people (students and teachers with pre-selection and basic training of sensory methodology. On the other hand artificial perception measurements were realized by electronic nose. Birch tree sap stability without addition of preservatives, both room temperature and refrigerated, is less than three days. The effectiveness of preservation of birch tree sap depends on the concentration of acids. Independently of storage temperature, samples that received stability during the whole one-month storage period, were those with potassium sorbate and three acids in the highest concentrations, ie. malic acid at 0.3%, citric acid at 0.5% and lactic acid at 0.5%. Unfortunately, concentrations of acids, which allow extension of shelf life at least for one month in a room temperature, are characterized by the worst sensory evaluation rating. Thus, they should be corrected by the use of additives for improving the flavor, such as fruit syrups or herbal extracts. On the other hand, additionally storage in a refrigerated conditions allows one-month-stability for the sample with the highest sensory evaluation rating, ie. with the addition of lactic acid at 0.1% and potassium sorbate, which taste not need to be corrected.

  1. Identification of SSR loci in Betula luminifera using birch EST data

    Institute of Scientific and Technical Information of China (English)

    LU Yong-quan; LI Hai-ying; JIA Qing; HUANG Hua-hong; TONG Zai-kang

    2011-01-01

    Expressed sequence tags (ESTs) are generated from single-pass sequencing of randomly picked cDNA clones and can be used for development of simple sequence repeat (SSR) markers or microsatellites.However,EST databases have been developed for only a small number of species.This paper provides a case study of the utility of freely available birch EST reources for the development of markers necessary for the genetic analysis of Betula luminifera.Based on birch EST data,primers for 80 EST-SSR candidate loci were developed and tested in birch.Of these,59 EST-SSR loci yielded single,stable and clear PCR products.We then tested the utility of those 59 markers in B.luminifera.The results showed 28 (47.6%) yielded stable and clear PCR products for at least one B.luminifera genotype.In addition,this study describes a rapid and inexpensive alternative for the development of SSRs in species with scarce available sequence data.

  2. Icelandic Birch Polyploids—The Case of a Perfect Fit in Genome Size

    Directory of Open Access Journals (Sweden)

    K. Anamthawat-Jónsson

    2010-01-01

    Full Text Available Two birch species coexist in Iceland, dwarf birch Betula nana and tree birch B. pubescens. Both species are variable morphologically, which has been shown to be due to introgressive hybridization via interspecific hybrids. The aim of this study was to examine if the introgression could be related to genome size. We characterized 42 plants from Bifröst woodland morphologically and cytogenetically. The population consisted of diploid B. nana (38%, tetraploid B. pubescens (55%, and triploid hybrids (7%. Genome size was measured from 12 plants, using Feulgen DNA image densitometry (FDM on spring leaf buds and flow cytometry (FCM with dormant winter twigs. The use of winter twigs for FCM is novel. The average 1C-values for diploid, triploid, and tetraploid plants were 448, 666, and 882 Mbp, respectively. Monoploid genome sizes were found to be statistically constant among ploidy levels. This stability is in contrast to the different taxonomic positions of the di- and tetraploids and also contrasts with the frequent occurrence of genome downsizing in polyploids.

  3. Growth of Scots Pine and Silver Birch Seedlings on Different Nursery Container Media

    Directory of Open Access Journals (Sweden)

    Fahrettin TILKI

    2014-12-01

    Full Text Available Peat has been the most common growing medium in tree nurseries, either alone or as a component of growing media mixes. However, as a result of increasing costs and decreasing amount of peat, seedling-growers are seeking more local growing medium components. In this study, container seedlings of Scots pine (Pinus sylvestris L. and silver birch (Betula pendula Roth were grown in pure peat and peat mixtures containing perlite and zeolite.  Physical parameters (height, shoot diameter, root dry weight, shoot dry weight, total dry weight were measured along with several morphological parameters (sturdiness quotient, height/diameter, shoot/root ratio. The zeolite additive in peat changed some media properties, and significant relation was established between some morphological attributes of seedlings and some medium properties in both species. On average, the seedlings grew best in pure peat, but zeolite additions to peat did not affect some morphological parameters negatively. The results suggest that zeolite has potential to be used as a component of peat based growing medium mixtures, and addition of zeolite to peat container medium in proportions of 10% by volume in Scots pine and up to 20% in silver birch was shown to be a feasible material for growing Scots pine and silver birch seedlings.

  4. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    Eric C. Xu; Yajun Zhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes.The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  5. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    EricC.Xu; YajunZhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes. The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  6. EFFECT OF THERMAL TREATMENT ON THE CHEMICAL COMPOSITION AND MECHANICAL PROPERTIES OF BIRCH AND ASPEN

    Directory of Open Access Journals (Sweden)

    Duygu Kocaefe

    2008-05-01

    Full Text Available The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The wood structure changes due to decomposition of hemicelluloses, ramification of lignin, and crystallization of cellulose. The wood becomes less hygroscopic. These changes improve the dimensional stability of wood, increase its resistance to micro-organisms, darken its color, and modify its hardness. However, wood also might loose some of its elasticity. Consequently, the heat treatment conditions have to be optimized. Therefore, it is important to understand the transformation of the chemical structure of wood caused by the treatment. In this study, the modification of the surface composition of the wood was followed with Fourier transform infrared spectroscopy (FTIR and inverse gas chromatography (IGC under different experimental conditions. The effect of maximum treatment temperatures on the chemical composition of Canadian birch and aspen as well as the correlations between their chemical transformation and different mechanical properties are presented. FTIR analysis results showed that the heat treatment affected the chemical composition of birch more compared to that of aspen. The results of IGC tests illustrated that the surfaces of the aspen and birch became more basic with heat treatment. The mechanical properties were affected by degradation of hemicellulose, ramification of lignin and cellulose crystallization.

  7. Mountain birch – potentially large source of sesquiterpenes into high latitude atmosphere

    Directory of Open Access Journals (Sweden)

    S. Haapanala

    2009-06-01

    Full Text Available Emissions of volatile organic compounds (VOCs from mountain birches were measured in Abisko, northern Sweden. Mountain birches make up majority of the tree biomass in Scandinavian high latitudes, area subject to significant climate warming. The measurements were carried out in two growing seasons. The emissions of a branch from four individual trees were measured in June–August 2006 and one of them again in July 2007. The measurements were conducted using a dynamic flow through chamber covered with Teflon film. The studied mountain birches were found to emit substantial amounts of linalool, monoterpenes and sesquiterpenes. The monoterpene emission was dominated by sabinene. The magnitude and composition of sesquiterpene emission changed dramatically between the years. For example, the average α-farnesene emission in 2006 was almost 2000 ng gdw−1 h−1 while in 2007 the emission of α-farnesene was negligible. Also the emissions of other sesquiterpenes decreased in 2007 to a fraction of that in 2006. One possible explanation for the change in emissions is the herbivory damage that occurred in the area in 2004. Herbivory is known to enhance the emissions of sesquiterpenes, especially those of α-farnesene, and the effect may last several years.

  8. Mountain birch – potentially large source of sesquiterpenes into high latitude atmosphere

    Directory of Open Access Journals (Sweden)

    A. Arneth

    2009-11-01

    Full Text Available Emissions of volatile organic compounds (VOCs from mountain birches were measured in Abisko, northern Sweden. Mountain birches make up the majority of the tree biomass in Scandinavian high latitudes, a region subject to significant climate warming. The measurements were carried out in two growing seasons. The emissions of four branches, each from a different individual tree, were measured in June–August 2006 and one of them again in July 2007. The measurements were conducted using a dynamic flow through chamber covered with Teflon film. The studied mountain birches were found to emit substantial amounts of linalool, monoterpenes and sesquiterpenes. The monoterpene emission was dominated by sabinene. The magnitude and composition of the sesquiterpene emission changed dramatically between the years. For example, the average α-farnesene emission potential in 2006 was almost 2600 ng gdw−1 h−1 (3.5 pmol gdw−1 s−1 while in 2007 α-farnesene was not detected at all. Also the emissions of other sesquiterpenes decreased in 2007 to a fraction of that in 2006. One possible explanation for the change in emissions is the herbivory damage that occurred in the area in 2004. Herbivory is known to enhance the emissions of sesquiterpenes, especially those of α-farnesene, and the effect may last for several years.

  9. Molecular biomarkers for grass pollen immunotherapy.

    Science.gov (United States)

    Popescu, Florin-Dan

    2014-03-26

    Grass pollen allergy represents a significant cause of allergic morbidity worldwide. Component-resolved diagnosis biomarkers are increasingly used in allergy practice in order to evaluate the sensitization to grass pollen allergens, allowing the clinician to confirm genuine sensitization to the corresponding allergen plant sources and supporting an accurate prescription of allergy immunotherapy (AIT), an important approach in many regions of the world with great plant biodiversity and/or where pollen seasons may overlap. The search for candidate predictive biomarkers for grass pollen immunotherapy (tolerogenic dendritic cells and regulatory T cells biomarkers, serum blocking antibodies biomarkers, especially functional ones, immune activation and immune tolerance soluble biomarkers and apoptosis biomarkers) opens new opportunities for the early detection of clinical responders for AIT, for the follow-up of these patients and for the development of new allergy vaccines.

  10. Vitality and storage condition of Syringa pollen

    Institute of Scientific and Technical Information of China (English)

    ZHOULi; LUOFeng-xia; DAILi-min; ZHANGHui-hua

    2003-01-01

    The fresh pollen vitality,the effect of different storage conditions on the pollen vitality,and the difference of vitality among the species of seven species of Syringa were determined in Shenyang,China.The results indicated that the pollen vitality (81.5%) of Syringa villosa was the highest among the seven tested species,followed by S.microphylla and S.meyeri,and that of S.oblata var.affinis was the lowest.The low temperature was the best condition for storage of pollen of Syringa,and the most proper temperature for the storage was 0-2℃.The storability of S.microphylla was the best of all,and it could be stored over 60 days at the temperature of 0-2℃,next was S.villosa and S.meyeri.

  11. Pollen-projektiga Rootsis / Lembit Jakobson

    Index Scriptorium Estoniae

    Jakobson, Lembit

    2009-01-01

    Avastusõppe projektist "Pollen" Eesti (2006-2009) mille eesmärk on kõiki lapsi kaasav uurimisõpe. Kevadisel koolivaheajal tutvus kümmekond Eesti õpetajat uurimisõppega Stockholmi kahes algkoolis

  12. Juniper Pollen Hotspots in the Southwest

    Science.gov (United States)

    Bunderson, L. D.; VandeWater, P.; Luvall, J.; Levetin, E.

    2013-01-01

    Rationale: Juniperus pollen is a major allergen in Texas, Oklahoma, and New Mexico. While the bulk of pollen may be released in rural areas, large amounts of pollen can be transported to urban areas. Major juniper species in the region include: Juniperus ashei, J. virginiana, J. pinchotii, and J. monosperma. Pollen release is virtually continuous beginning in late September with J. pinchotii and ending in May with J. monosperma. Urban areas in the region were evaluated for the potential of overlapping seasons in order to inform sensitive individuals. Methods: Burkard volumetric pollen traps were established for two consecutive spring seasons at 6 sites in northern New Mexico and 6 sites for two consecutive winter and fall seasons in Texas and Oklahoma Standard methods were used in the preparation and analysis of slides. Results: The Dallas-Fort Worth Metroplex is home to over 6 million people. It is adjacent to populations of J. pinchotii, J. virginiana, and J. ashei. Peak concentration near Dallas for J. ashei in 2011 was 5891 pollen grains/m3 in January 7th. The peak date for J. pinchotii at an upwind sampling location in San Marcos, TX was November 1, 2010 and peak for J. virginiana at a nearby station in Tulsa, OK was November 1, 2010 and peak for J. virginiana at a nearby station in Tulsa, OK was February 20, 2011. Amarillo, TX is adjacent to J. pinchotii, J. ashei, and J. monosperma populations and may be subject to juniper pollen from September through May. Conclusions: Considering the overlapping distributions of juniper trees and the overlapping temporal release of pollen, sensitive patients may benefit from avoiding hotspots.

  13. Influence of pollen nutrition on honey bee health: do pollen quality and diversity matter?

    Science.gov (United States)

    Di Pasquale, Garance; Salignon, Marion; Le Conte, Yves; Belzunces, Luc P; Decourtye, Axel; Kretzschmar, André; Suchail, Séverine; Brunet, Jean-Luc; Alaux, Cédric

    2013-01-01

    Honey bee colonies are highly dependent upon the availability of floral resources from which they get the nutrients (notably pollen) necessary to their development and survival. However, foraging areas are currently affected by the intensification of agriculture and landscape alteration. Bees are therefore confronted to disparities in time and space of floral resource abundance, type and diversity, which might provide inadequate nutrition and endanger colonies. The beneficial influence of pollen availability on bee health is well-established but whether quality and diversity of pollen diets can modify bee health remains largely unknown. We therefore tested the influence of pollen diet quality (different monofloral pollens) and diversity (polyfloral pollen diet) on the physiology of young nurse bees, which have a distinct nutritional physiology (e.g. hypopharyngeal gland development and vitellogenin level), and on the tolerance to the microsporidian parasite Nosemaceranae by measuring bee survival and the activity of different enzymes potentially involved in bee health and defense response (glutathione-S-transferase (detoxification), phenoloxidase (immunity) and alkaline phosphatase (metabolism)). We found that both nurse bee physiology and the tolerance to the parasite were affected by pollen quality. Pollen diet diversity had no effect on the nurse bee physiology and the survival of healthy bees. However, when parasitized, bees fed with the polyfloral blend lived longer than bees fed with monofloral pollens, excepted for the protein-richest monofloral pollen. Furthermore, the survival was positively correlated to alkaline phosphatase activity in healthy bees and to phenoloxydase activities in infected bees. Our results support the idea that both the quality and diversity (in a specific context) of pollen can shape bee physiology and might help to better understand the influence of agriculture and land-use intensification on bee nutrition and health.

  14. Influence of pollen nutrition on honey bee health: do pollen quality and diversity matter?

    Directory of Open Access Journals (Sweden)

    Garance Di Pasquale

    Full Text Available Honey bee colonies are highly dependent upon the availability of floral resources from which they get the nutrients (notably pollen necessary to their development and survival. However, foraging areas are currently affected by the intensification of agriculture and landscape alteration. Bees are therefore confronted to disparities in time and space of floral resource abundance, type and diversity, which might provide inadequate nutrition and endanger colonies. The beneficial influence of pollen availability on bee health is well-established but whether quality and diversity of pollen diets can modify bee health remains largely unknown. We therefore tested the influence of pollen diet quality (different monofloral pollens and diversity (polyfloral pollen diet on the physiology of young nurse bees, which have a distinct nutritional physiology (e.g. hypopharyngeal gland development and vitellogenin level, and on the tolerance to the microsporidian parasite Nosemaceranae by measuring bee survival and the activity of different enzymes potentially involved in bee health and defense response (glutathione-S-transferase (detoxification, phenoloxidase (immunity and alkaline phosphatase (metabolism. We found that both nurse bee physiology and the tolerance to the parasite were affected by pollen quality. Pollen diet diversity had no effect on the nurse bee physiology and the survival of healthy bees. However, when parasitized, bees fed with the polyfloral blend lived longer than bees fed with monofloral pollens, excepted for the protein-richest monofloral pollen. Furthermore, the survival was positively correlated to alkaline phosphatase activity in healthy bees and to phenoloxydase activities in infected bees. Our results support the idea that both the quality and diversity (in a specific context of pollen can shape bee physiology and might help to better understand the influence of agriculture and land-use intensification on bee nutrition and health.

  15. Pollen dispersal analysis using DNA markers

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    2014-01-01

    Full Text Available Modes of pollen dispersal are important for plant ecology, conservation, and evolutionary biology as pollen-mediated gene flow connects one generation of sexually-reproducing plants to the next. With the development of DNA molecular techniques, molecular markers (especially microsatellite markers have replaced traditional physical markers for pollen flow analysis. Methods of paternity assignment with maximum likelihood and Bayesian inference have greatly improved the estimation of pollen flow characteristics with regard to direction, distance, and strength. Pollen dispersal curves have been characterized by single parameter, two-parameter, multi-parameter, and two-component composite models to better evaluate the shape of dispersal distributions. These innovative techniques and methods have been successfully applied to assess pollination patterns in studies of plant sexual polymorphism, population connectivity, and natural hybridization, which, in turn, have provided important insights into basic theories of evolution, ecology, and conservation. In the coming years, high-throughput sequencing technologies are expected to accelerate the application of molecular marker-based pollen flow analysis across a wide range of plant taxa.

  16. Pollen and sperm heteromorphism: convergence across kingdoms?

    Science.gov (United States)

    Till-Bottraud, I; Joly, D; Lachaise, D; Snook, R R

    2005-01-01

    Sperm competition theory predicts that males should produce many, similar sperm. However, in some species of animals and plants, males exhibit a heteromorphism that results in the production of at least two different types of sperm or pollen grains. In animals, sperm heteromorphism typically corresponds to the production of one fertile morph and one (or more) sterile morph(s), whereas in plants two or more pollen morphs (one of which can be either sterile or fertile) are produced in all flowers but sometimes in different anthers. Heteromorphism has arisen independently several times across phyla and at different phylogenetic levels. Here, we compare and contrast sperm and pollen heteromorphism and discuss the evolutionary hypotheses suggested to explain heteromorphism in these taxa. These hypotheses include facilitation, nutritive contribution, blocking, cheap filler, sperm flushing or killing for animals; outcrossing and precise cross-pollen transfer or bet-hedging strategy for plants; cryptic female choice for both. We conclude that heteromorphism in the two phyla is most likely linked to a general evolutionary response to sexual selection, either to increase one male's sperm or pollen success in competition with other males, or mediate male/female interactions. Therefore, although sperm and pollen are not homologous, we suggest that heteromorphism represents an example of convergence across kingdoms.

  17. Plant Sterol Diversity in Pollen from Angiosperms.

    Science.gov (United States)

    Villette, Claire; Berna, Anne; Compagnon, Vincent; Schaller, Hubert

    2015-08-01

    Here we have examined the composition of free sterols and steryl esters of pollen from selected angiosperm species, as a first step towards a comprehensive analysis of sterol biogenesis in the male gametophyte. We detected four major sterol structural groups: cycloartenol derivatives bearing a 9β,19-cyclopropyl group, sterols with a double bond at C-7(8), sterols with a double bond at C-5(6), and stanols. All these groups were unequally distributed among species. However, the distribution of sterols as free sterols or as steryl esters in pollen grains indicated that free sterols were mostly Δ(5)-sterols and that steryl esters were predominantly 9β,19-cyclopropyl sterols. In order to link the sterol composition of a pollen grain at anthesis with the requirement for membrane lipid constituents of the pollen tube, we germinated pollen grains from Nicotiana tabacum, a model plant in reproductive biology. In the presence of radiolabelled mevalonic acid and in a time course series of measurements, we showed that cycloeucalenol was identified as the major neosynthesized sterol. Furthermore, the inhibition of cycloeucalenol neosynthesis by squalestatin was in full agreement with a de novo biogenesis and an apparent truncated pathway in the pollen tube.

  18. Pollen-related allergy in Europe.

    Science.gov (United States)

    D'Amato, G; Spieksma, F T; Liccardi, G; Jäger, S; Russo, M; Kontou-Fili, K; Nikkels, H; Wüthrich, B; Bonini, S

    1998-06-01

    The increasing mobility of Europeans for business and leisure has led to a need for reliable information about exposure to seasonal airborne allergens during travel abroad. Over the last 10 years or so, aeropalynologic and allergologic studies have progressed to meet this need, and extensive international networks now provide regular pollen and hay-fever forecasts. Europe is a geographically complex continent with a widely diverse climate and a wide spectrum of vegetation. Consequently, pollen calendars differ from one area to another; however, on the whole, pollination starts in spring and ends in autumn. Grass pollen is by far the most frequent cause of pollinosis in Europe. In northern Europe, pollen from species of the family Betulaceae is a major cause of the disorder. In contrast, the mild winters and dry summers of Mediterranean areas favor the production of pollen types that are rarely found in central and northern areas of the continent (e.g., the genera Parietaria, Olea, and Cupressus). Clinical and aerobiologic studies show that the pollen map of Europe is changing also as a result of cultural factors (e.g., importation of plants for urban parklands) and greater international travel (e.g., the expansion of the ragweed genus Ambrosia in France, northern Italy, Austria, and Hungary). Studies on allergen-carrying paucimicronic or submicronic airborne particles, which penetrate deep into the lung, are having a relevant impact on our understanding of pollinosis and its distribution throughout Europe.

  19. Morphological Research on Indigenous Sambucus Species Pollen

    Directory of Open Access Journals (Sweden)

    Mircea TAMAS

    2009-06-01

    Full Text Available The pollen grains have a definite shape, size, colour, structure for each species, genus and family and these characters are useful for systematical botany. The pollen has nutritive properties due to its content: proteins, lipids, carbohydrates, vitamins, hormones and minerals. In the Romanian flora vegetate three species of Sambucus, but only S. nigra L. (elder or black elder supplies a vegetal medical product, Sambuci flos or elder flowers, whereas the others species S. ebulus L. (dwarf elder and S. racemosa L. (mountain elder or red elder are considered adulterations. The pollen of Sambucus species were already studied using optical microscopy (Tarnavschi et al., but the images are in one single layout, therefore the structure details cannot be easily notice. In this context the pollen grains of the three species already mentioned above were studied by SEM (Scanning Electron Microscopy. The results demonstrated that this pollen have a small-middle size, oblat-sphaeroidal-prolat shape, threecolpat and the exine adornments are of reticulate type, haemitectate with sticks in the meshs of polygonale net. The flavonoids content is lower than in others species (0.146-0.564 %. The SEM analyse of Sambucus pollen allow a reliable identification of the genus but less for the species.

  20. Seasonal variation in diurnal atmospheric grass pollen concentration profiles

    DEFF Research Database (Denmark)

    Peel, Robert George; Ørby, Pia Viuf; Skjøth, Carsten Ambelas

    2014-01-01

    In this study, the diurnal atmospheric grass pollen concentration profile within the Danish city of Aarhus was shown to change in a systematic manner as the pollen season progressed. Although diurnal grass pollen profiles can differ greatly from day-to-day, it is common practice to establish...... the time of day when peak concentrations are most likely to occur using seasonally averaged diurnal profiles. Atmospheric pollen loads are highly dependent upon emissions, and different species of grass are known to flower and emit pollen at different times of the day and during different periods...... of the pollen season. Pollen concentrations are also influenced by meteorological factors - directly through those parameters that govern pollen dispersion and transport, and indirectly through the weather-driven flowering process. We found that three different profiles dominated the grass pollen season...

  1. The Lateglacial and Postglacial vegetation history of the northwestern limits of Beringia, based on pollen, stomate and tree stump evidence

    Science.gov (United States)

    Pisaric, M. F. J.; MacDonald, G. M.; Velichko, A. A.; Cwynar, L. C.

    2001-01-01

    In order to reconstruct the Late- and Postglacial vegetation history of the northwestern edge of Beringia, a sediment core was collected from a lake north of the present treeline along the lower Lena River of northeastern Siberia, and analysed for fossil pollen and stomates. In addition, fossil tree stumps were collected in the vicinity of the lake. Eight radiocarbon dates indicate that the lake sediment record spans at least the past 12,300 yr BP. The early vegetation at this site was dominated by herb and shrub tundra. Possible evidence of Younger Dryas cooling, consisting of a decrease in shrub birch and increases in grass and herbaceous plants, occurs between 11,000 and 10,000 yr BP. Forests, dominated by Larix dahurica and including Picea obovata, extended northward to the site between 8500 and 3500 yr BP. There is an agreement between the pollen, stomate and tree stump evidence for this advance. The modern vegetation of shrub tundra was established after 3500 yr BP.

  2. Does an 'oversupply' of ovules cause pollen limitation?

    Science.gov (United States)

    Rosenheim, Jay A; Schreiber, Sebastian J; Williams, Neal M

    2016-04-01

    Lifetime seed production can be constrained by shortfalls of pollen receipt ('pollen limitation'). The ovule oversupply hypothesis states that, in response to unpredictable pollen availability, plants evolve to produce more ovules than they expect to be fertilized, and that this results in pollen limitation of seed production. Here, we present a cartoon model and a model of optimal plant reproductive allocations under stochastic pollen receipt to evaluate the hypothesis that an oversupply of ovules leads to increased pollen limitation. We show that an oversupply of ovules has two opposing influences on pollen limitation of whole-plant seed production. First, ovule oversupply increases the likelihood that pollen receipt limits the number of ovules that can be fertilized ('prezygotic pollen limitation'). Second, ovule oversupply increases the proportion of pollen grains received that are used to fertilize ovules ('pollen use efficiency'). As a result of these opposing influences, ovule oversupply has only a modest effect on the degree to which lifetime seed production is constrained by pollen receipt, producing a small decrease in the incidence of pollen limitation. Ovule oversupply is not the cause of the pollen limitation problem, but rather is part of the evolutionary solution to that problem.

  3. Sensitization to cereals and peanut evidenced by skin prick test and specific IgE in food-tolerant, grass pollen allergic patients

    Directory of Open Access Journals (Sweden)

    Martens Maria

    2011-12-01

    Full Text Available Abstract Background The botanical relation between grass and cereal grains may be relevant when diagnosing food allergy to cereals. The aim was to investigate the diagnostic specificity of skin prick test (SPT and specific immunoglobulin E (sIgE tests to cereals and peanut in grass pollen allergic subjects without history of, and clinically reactions to foods botanically related to grass. Methods 70 subjects (41 females; mean age 32 years and 20 healthy controls (13 females; mean age 24 years were tested by open food challenge (OFC with cereals and peanut. SPT and sIgE both with Immulite® (Siemens and ImmunoCAP® (Phadia to grass and birch pollen, cereals, peanut and bromelain were performed. Results Of the 65 OFC-negative subjects 29-46% (SPT, depending on cut-off, 20% (Immulite and 38% (ImmunoCAP had positive results to one or more of the foods tested. Controls were negative in all tests. Cross-reactive carbohydrate determinants (CCD as evidenced by reaction to bromelain could explain only a minority of the measured IgE-sensitizations. Conclusion Grass pollen allergic patients with documented food tolerance to cereals and peanut may express significant sensitization. False-positive cereal or peanut allergy diagnoses may be a quantitatively important problem both in routine clinical work and epidemiological studies.

  4. A 12,000-Yr Pollen Record off Cape Hatteras: Pollen Sources and Mechanisms of Pollen Dispersion

    Science.gov (United States)

    Naughton, F.; Keigwin, L.; Peteet, D.; Costas, S.; Desprat, S.; Oliveira, D.; de Vernal, A.; Voelker, A.; Abrantes, F.

    2015-01-01

    Integrating both marine and terrestrial signals from the same sediment core is one of the primary challenges for understanding the role of ocean-atmosphere coupling throughout past climate changes. It is therefore vital to understand how the pollen signal of a given marine record reflects the vegetation changes of the neighboring continent. The comparison between the pollen record of marine core JPC32 (KNR178JPC32) and available terrestrial pollen sequences from eastern North America over the last 12,170 years indicates that the pollen signature off Cape Hatteras gives an integrated image of the regional vegetation encompassing the Pee Dee river, Chesapeake and Delaware hydrographic basins and is reliable in reconstructing the past climate of the adjacent continent. Extremely high quantities of pollen grains included in the marine sediments off Cape Hatteras were transferred from the continent to the sea, at intervals 10,100-8800 cal yr BP, 8300-7500 cal yr BP, 5800- 4300 cal yr BP and 2100-730 cal yr BP, during storm events favored by episodes of rapid sea-level rise in the eastern coast of US. In contrast, pollen grains export was reduced during 12,170-10,150 cal yr BP and 4200- 2200 cal yr BP, during episodes of intense continental dryness and slow sea level rise episodes or lowstands in the eastern coast of US. The near absence of reworked pollen grains in core JPC32 contrasts with the high quantity of reworked material in nearby but deeper located marine sites, suggesting that the JPC32 recordwas not affected by the DeepWestern Boundary Current (DWBC) since the end of the Younger Dryas and should be considered a key site for studying past climate changes in the western North Atlantic.

  5. Pollen of Southeast Asian Alchornea (Euphorbiaceae), with an overview of the pollen fossil record

    NARCIS (Netherlands)

    Bulalacao, L.J.; Ham, van der R.W.J.M.

    2003-01-01

    In order to evaluate pollen morphological descriptions of Alchornea in the literature, which are almost completely based on African and American species, the pollen of eight Southeast Asian species of Alchornea was investigated, using light and scanning electron microscopy. Very little variation app

  6. Primary identification, biochemical characterization, and immunologic properties of the allergenic pollen cyclophilin cat R 1.

    Science.gov (United States)

    Ghosh, Debajyoti; Mueller, Geoffrey A; Schramm, Gabriele; Edwards, Lori L; Petersen, Arnd; London, Robert E; Haas, Helmut; Gupta Bhattacharya, Swati

    2014-08-01

    Cyclophilin (Cyp) allergens are considered pan-allergens due to frequently reported cross-reactivity. In addition to well studied fungal Cyps, a number of plant Cyps were identified as allergens (e.g. Bet v 7 from birch pollen, Cat r 1 from periwinkle pollen). However, there are conflicting data regarding their antigenic/allergenic cross-reactivity, with no plant Cyp allergen structures available for comparison. Because amino acid residues are fairly conserved between plant and fungal Cyps, it is particularly interesting to check whether they can cross-react. Cat r 1 was identified by immunoblotting using allergic patients' sera followed by N-terminal sequencing. Cat r 1 (∼ 91% sequence identity to Bet v 7) was cloned from a cDNA library and expressed in Escherichia coli. Recombinant Cat r 1 was utilized to confirm peptidyl-prolyl cis-trans-isomerase (PPIase) activity by a PPIase assay and the allergenic property by an IgE-specific immunoblotting and rat basophil leukemia cell (RBL-SX38) mediator release assay. Inhibition-ELISA showed cross-reactive binding of serum IgE from Cat r 1-allergic individuals to fungal allergenic Cyps Asp f 11 and Mala s 6. The molecular structure of Cat r 1 was determined by NMR spectroscopy. The antigenic surface was examined in relation to its plant, animal, and fungal homologues. The structure revealed a typical cyclophilin fold consisting of a compact β-barrel made up of seven anti-parallel β-strands along with two surrounding α-helices. This is the first structure of an allergenic plant Cyp revealing high conservation of the antigenic surface particularly near the PPIase active site, which supports the pronounced cross-reactivity among Cyps from various sources.

  7. Pollen grain sporoderm and types of dispersal units

    Directory of Open Access Journals (Sweden)

    Ettore Pacini

    2014-01-01

    Full Text Available The pollen of gymnosperms and angiosperms may be dispersed in monads, tetrads, polyads, massulae or compact pollinia. The monads and tetrads may form larger clumps of pollen because filiform pollen is tangled while other kinds of pollen can be glued by means of different devices. Exine and intine modify their structure to adapt to pollen dispersing units, exine in some cases can be absent. An additional layer, a thin callosic wall, can be present in some species beneath the intine; this occurs when pollen grains are slightly dehydrated before dispersal.

  8. Transport logistics in pollen tubes.

    Science.gov (United States)

    Chebli, Youssef; Kroeger, Jens; Geitmann, Anja

    2013-07-01

    Cellular organelles move within the cellular volume and the effect of the resulting drag forces on the liquid causes bulk movement in the cytosol. The movement of both organelles and cytosol leads to an overall motion pattern called cytoplasmic streaming or cyclosis. This streaming enables the active and passive transport of molecules and organelles between cellular compartments. Furthermore, the fusion and budding of vesicles with and from the plasma membrane (exo/endocytosis) allow for transport of material between the inside and the outside of the cell. In the pollen tube, cytoplasmic streaming and exo/endocytosis are very active and fulfill several different functions. In this review, we focus on the logistics of intracellular motion and transport processes as well as their biophysical underpinnings. We discuss various modeling attempts that have been performed to understand both long-distance shuttling and short-distance targeting of organelles. We show how the combination of mechanical and mathematical modeling with cell biological approaches has contributed to our understanding of intracellular transport logistics.

  9. Recombinant allergens for pollen immunotherapy.

    Science.gov (United States)

    Wallner, Michael; Pichler, Ulrike; Ferreira, Fatima

    2013-12-01

    Specific immunotherapy (IT) represents the only potentially curative therapeutic intervention of allergic diseases capable of suppressing allergy-associated symptoms not only during treatment, but also after its cessation. Presently, IT is performed with allergen extracts, which represent a heterogeneous mixture of allergenic, as well as nonallergenic, compounds of a given allergen source. To overcome many of the problems associated with extract-based IT, strategies based on the use of recombinant allergens or derivatives thereof have been developed. This review focuses on recombinant technologies to produce allergy therapeuticals, especially for allergies caused by tree, grass and weed pollen, as they are among the most prevalent allergic disorders affecting the population of industrialized societies. The reduction of IgE-binding of recombinant allergen derivatives appears to be mandatory to increase the safety profile of vaccine candidates. Moreover, increased immunogenicity is expected to reduce the dosage regimes of the presently cumbersome treatment. In this regard, it has been convincingly demonstrated in animal models that hypoallergenic molecules can be engineered to harbor inherent antiallergenic immunologic properties. Thus, strategies to modulate the allergenic and immunogenic properties of recombinant allergens will be discussed in detail. In recent years, several successful clinical studies using recombinant wild-type or hypoallergens as active ingredients have been published and, currently, novel treatment forms with higher safety and efficacy profiles are under investigation in clinical trials. These recent developments are summarized and discussed.

  10. Ozone affects pollen viability and NAD(P)H oxidase release from Ambrosia artemisiifolia pollen

    Energy Technology Data Exchange (ETDEWEB)

    Pasqualini, Stefania, E-mail: spas@unipg.it [Department of Applied Biology, University of Perugia, Perugia (Italy); Tedeschini, Emma; Frenguelli, Giuseppe [Department of Applied Biology, University of Perugia, Perugia (Italy); Wopfner, Nicole; Ferreira, Fatima [Department of Molecular Biology, CD Laboratory for Allergy Diagnosis and Therapy, University of Salzburg, Salzburg (Austria); D' Amato, Gennaro [Division of Respiratory and Allergic Diseases, ' A. Cardarelli' High Speciality Hospital, Naples (Italy); Ederli, Luisa [Department of Applied Biology, University of Perugia, Perugia (Italy)

    2011-10-15

    Air pollution is frequently proposed as a cause of the increased incidence of allergy in industrialised countries. We investigated the impact of ozone (O{sub 3}) on reactive oxygen species (ROS) and allergen content of ragweed pollen (Ambrosia artemisiifolia). Pollen was exposed to acute O{sub 3} fumigation, with analysis of pollen viability, ROS and nitric oxide (NO) content, activity of nicotinamide adenine dinucleotide phosphate (NAD[P]H) oxidase, and expression of major allergens. There was decreased pollen viability after O{sub 3} fumigation, which indicates damage to the pollen membrane system, although the ROS and NO contents were not changed or were only slightly induced, respectively. Ozone exposure induced a significant enhancement of the ROS-generating enzyme NAD(P)H oxidase. The expression of the allergen Amb a 1 was not affected by O{sub 3}, determined from the mRNA levels of the major allergens. We conclude that O{sub 3} can increase ragweed pollen allergenicity through stimulation of ROS-generating NAD(P)H oxidase. - Highlights: > O{sub 3} reduces the viability of ragweed pollen. > ROS and allergens of ragweed pollen were not affected by O{sub 3} exposure. > O{sub 3} enhances the activity of the ROS-generating enzyme NAD(P)H oxidase. > O{sub 3} increases ragweed pollen allergenicity through NAD(P)H-oxidase stimulation. - This study focuses on the effects of the atmospheric pollutant ozone on ROS content and NAD(P)H oxidase activity of ragweed pollen grains.

  11. Wind-pollination and the roles of pollen allergenic proteins.

    Science.gov (United States)

    Songnuan, Wisuwat

    2013-12-01

    Over the past few decades, there has been an explosion of understanding of the molecular nature of major allergens contained within pollens from the most important allergenic plant species. Most major allergens belong to only a few protein families. Protein characteristics, cross-reactivity, structures, and IgE binding epitopes have been determined for several allergens. These efforts have led to significant improvements in specific immunotherapy, yet there has been little discussion about the physiological functions of these proteins. Even with large amounts of available information about allergenic proteins from pollens, the incidence of pollen allergy continuously increases worldwide. The reason for this increase is unclear and is most likely due to a combination of factors. One important culprit might be a change in the pollen itself. Knowledge about pollen biology and how pollen is changing as a result of more extreme environmental conditions might improve our understanding of the disease. This review focuses on the characteristics of plants producing allergenic pollens that are relevant to pollen allergy, including the phylogenetic relationships, pollen dispersal distances, amounts of pollen produced, amounts of protein in each type of pollen, and how allergenic proteins are released from pollens. In addition, the physiological roles of major allergenic protein families will be discussed to help us understand why some of these proteins become allergens and why GMO plants with hypoallergenic pollens may not be successful.

  12. Bees associate colour cues with differences in pollen rewards.

    Science.gov (United States)

    Nicholls, Elizabeth; de Ibarra, Natalie Hempel

    2014-08-01

    In contrast to the wealth of knowledge concerning sucrose-rewarded learning, the question of whether bees learn when they collect pollen from flowers has been little addressed. The nutritional value of pollen varies considerably between species, and it may be that bees learn the features of flowers that produce pollen best suited to the dietary requirements of their larvae. It is still unknown, however, whether a non-ingestive reward pathway for pollen learning exists, and how foraging bees sense differences between pollen types. Here we adopt a novel experimental approach testing the learning ability of bees with pollen rewards. Bumblebees were reared under controlled laboratory conditions. To establish which pollen rewards are distinguishable, individual bees were given the choice of collecting two types of pollen, diluted to varying degrees with indigestible α-cellulose. Bees preferentially collected a particular pollen type, but this was not always the most concentrated sample. Preferences were influenced by the degree of similarity between samples and also by the period of exposure, with bees more readily collecting samples of lower pollen concentration after five trials. When trained differentially, bees were able to associate an initially less-preferred contextual colour with the more concentrated sample, whilst their pollen preferences did not change. Successful learning of contextual cues seems to maintain pollen foraging preferences over repeated exposures, suggesting that fast learning of floral cues may preclude continuous sampling and evaluation of alternative reward sources, leading to constancy in pollen foraging.

  13. Regulation of Pollen Tube Growth by Transglutaminase

    Directory of Open Access Journals (Sweden)

    Giampiero Cai

    2013-03-01

    Full Text Available In pollen tubes, cytoskeleton proteins are involved in many aspects of pollen germination and growth, from the transport of sperm cells to the asymmetrical distribution of organelles to the deposition of cell wall material. These activities are based on the dynamics of the cytoskeleton. Changes to both actin filaments and microtubules are triggered by specific proteins, resulting in different organization levels suitable for the different functions of the cytoskeleton. Transglutaminases are enzymes ubiquitous in all plant organs and cell compartments. They catalyze the post-translational conjugation of polyamines to different protein targets, such as the cytoskeleton. Transglutaminases are suggested to have a general role in the interaction between pollen tubes and the extracellular matrix during fertilization and a specific role during the self-incompatibility response. In such processes, the activity of transglutaminases is enhanced, leading to the formation of cross-linked products (including aggregates of tubulin and actin. Consequently, transglutaminases are suggested to act as regulators of cytoskeleton dynamics. The distribution of transglutaminases in pollen tubes is affected by both membrane dynamics and the cytoskeleton. Transglutaminases are also secreted in the extracellular matrix, where they may take part in the assembly and/or strengthening of the pollen tube cell wall.

  14. From pollen actin to crop male sterility

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Actin plays an important role in the life activity of animal and plant cells. Pollen cells have plenty of actin whose structure and characteristics are very similar to the animal actin. The nucleotide sequence and amino acid sequence of plant actin gene are very similar to those of the animal gene. The content of pollen actin from male sterile plants is much more lower than that from its maintainer plants. The expression of actin gene is organ-specific during the plant development. The expression quantity of actin gene in pollen is much more higher than those from root, stem and leaf. The expression plasmid of the anti-sense actin gene was constructed, transferred to the protoplasts of wheat and tomato to inhibit the expression of actin gene in pollen and thus the male sterile plants of wheat and tomato were obtained. The actin in pollens from the transgenic plants was reduced significantly, whereas the pistil was not affected. This study might pave a new way to breeding male sterile lines for the application of hybrid vigor of wheat and tomato.

  15. Occupational Allergy to Peach (Prunus persica) Tree Pollen and Potential Cross-Reactivity between Rosaceae Family Pollens.

    Science.gov (United States)

    Jiang, Nannan; Yin, Jia; Mak, Philip; Wen, Liping

    2015-10-01

    Orchard workers in north China are highly exposed to orchard pollens, especially peach and other Rosaceae family pollens during pollination season. The aim of this study was to investigate whether occupational allergy to peach tree pollen as a member of Rosaceae family is IgE-mediated and to evaluate the cross-reactivity among Rosaceae family pollens. Allergen skin test and conjunctival challenge test were performed; enzyme linked immune-sorbent assay (ELISA), inhibiting ELISA, western immunoblotting and inhibiting western immunoblotting were done with Rosaceae family orchard pollens, including peach, apricot, cherry, apple and pear tree pollens. Mass spectrometry was also performed to probe the main allergen component and cross-reactive protein. Sensitizations to peach pollen were found in both skin test and conjunctival challenge in the patients. Serum specific IgE to three pollens (peach, apricot and cherry) were detected through ELISA. When peach pollen used as solid phase, ELISA inhibition revealed other four kinds of pollens capable of inducing partial to strong inhibitions (45% to 87%), with the strongest inhibition belonging to apricot pollen (87%). Western blotting showed predominant IgE binding to a 20 KD protein among these pollens, which appeared to be a cross-reactive allergen component through western blotting inhibition. It was recognized as a protein homologous to glutathione s-transferase 16 from Arabidopsis thaliana. Peach and other Rosaceae family tree pollen may serve as a potential cause of IgE mediated occupational respiratory disease in orchard workers in north China.

  16. The Effects of Low-Energy Nitrogen Ion Implantation on Pollen Exine Substructure and Pollen Germination of Cedrus deodara

    Institute of Scientific and Technical Information of China (English)

    Li Guoping; Huang Qunce; Qin Guangyong; Huo Yuping

    2005-01-01

    The aim of this study is to investigate the biological effects of ion beams on pollen.Pollen grains of Cedrus deodara were implanted with 30 keV nitrogen ion beams at doses ranging from 1 × 1015 ions/cm2 to 15 × 1015 ions/cm2. The effects of N+ implantation on the pollen exine substructure were examined using an atomic force microscope (AFM), and the structure and morphology of pollen and pollen tubes were observed using a laser scanning confocal microscope (LSCM). AFM observations distinctly revealed the erosion of the pollen exine caused by N+implantation in the micrometer to nanometer range. Typical results showed that the erosion degree was linearly proportional to the ion dose. Pollen germination experiments in vitro indicated that N+ implantation within a certain dose range increased the rate of pollen germination. The main abnormal phenomena in pollen tubes were also analyzed. Our results suggest that low energy ion implantation with suitable energy and dosage can be used to break the pollen wall to induce a transfer of exogenous DNA into the pollen without any damage to the cytoplasm and nuclei of the pollen. The present study suggests that a combination of the method of ion-beam-induced gene transfer and the pollen-tube pathway method (PTPW) would be a new plant transformation method.

  17. The mechanism and key molecules involved in pollen tube guidance.

    Science.gov (United States)

    Higashiyama, Tetsuya; Takeuchi, Hidenori

    2015-01-01

    During sexual reproduction of flowering plants, pollen tube guidance by pistil tissue is critical for the delivery of nonmotile sperm cells to female gametes. Multistep controls of pollen tube guidance can be divided into two phases: preovular guidance and ovular guidance. During preovular guidance, various female molecules, including stimulants for pollen germination and pollen tube growth, are provided to support tube growth toward the ovary, where the ovules are located. After entering the ovary, pollen tubes receive directional cues from their respective target ovules, including attractant peptides for precise, species-preferential attraction. Successful pollen tube guidance in the pistil requires not only nutritional and directional controls but also competency controls to make pollen tubes responsive to guidance cues, regulation to terminate growth once a pollen tube arrives at the target, and strategies to stop ovular attraction depending on the fertilization of female gametes.

  18. Controlling Hay Fever Symptoms with Accurate Pollen Counts

    Science.gov (United States)

    ... counts Share | Controlling Hay Fever Symptoms with Accurate Pollen Counts This article has been reviewed by Thanai ... rhinitis known as hay fever is caused by pollen carried in the air during different times of ...

  19. A Pollen Primer | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... please turn Javascript on. Feature: Managing Allergies A Pollen Primer Past Issues / Summer 2011 Table of Contents ... National Institute of Environmental Health Sciences (NIEHS) . Plant Pollen Ragweed and other weeds, such as curly dock, ...

  20. Isolation and identification of plant phenolic compounds in birch leaves: Air pollution stress and leaf phenolics

    Science.gov (United States)

    Loponen, Jyrki Mikael

    Chromatographic (analytical and preparative HPLC), chemical (hydrolysis) and spectroscopic (UV, 1H NMR, 13C NMR and MS) techniques proved to be suitable tools for the structure identification of plant phenolic compounds. More than 30 individual phenolic compounds were detected and quantified. Detailed information of the structures of individual compounds was determined after isolation from birch leaves. Ten flavonoid glycosides were identified. Two of them, myricetin-3-O-α-L-(acetyl)-rhamnopyranoside and quercetin-3-O-α-L-(4/prime'-O-acetyl)- rhamnopyranoside, have been rarely found in birch leaves. Further, some characterized major phenolics with non- flavonoid structures in our study were 1-O-galloyl- β-D-(2-O-acetyl)-glucopyranose, gallic, chlorogenic, neochlorogenic, cis- and trans-forms of 3- and 5-p-coumaroylquinic acids. The presence of gallotannin group was evidenced by strong positive correlations between concentrations of these gallotannins (preliminary identified by HPLC and UV spectra) and the protein precipitation capacity of extracts. Content of gallotannins decreased with leaf growth and maturation. It is known that concentrations of phenolic compounds regularly increase in slowly growing stressed plants and therefore, it is natural that they are also sensitive to different forms of air pollution. Total content and the contents of some individual phenolics correlated negatively with the distance from the pollution source in our study area. In addition to comparing absolute concentrations of compounds in question, the within-tree correlations or within-tree variations of the relevant compounds between polluted and control areas were an alternative approach. Differences in pairwise correlations between the investigated leaf phenolic compounds indicated the competition between some gallotannins and p-coumaroylquinic acids on the polluted but not on the control site. Air pollution seems to be a stress factor for birch trees associated with

  1. Adaptive Responses of Birch-Leaved Pear (Pyrus betulaefolia Seedlings to Salinity Stress

    Directory of Open Access Journals (Sweden)

    Qiang Sheng WU

    2009-06-01

    Full Text Available One-year-old birch-leaved pear (Pyrus betulaefolia Bunge seedlings were subjected to 0, 50, 100, 150, and 200 mmol/L NaCl solutions for 27 days in order to study the effects of salinity stress on photosynthesis, ion accumulation and enzymatic and non-enzymatic scavenging of reactive oxygen species in the seedlings. The research was performed in a greenhouse using potted trees. Salinity stress reduced photosynthetic rates, stomatal conductance and water use efficiency of leaves of the pear seedlings, but increased transpiration rates and leaf temperature. Hydrogen peroxide and superoxide anion radical contents increased with increasing NaCl concentrations, a phenomena also observed for malondialdehyde, suggesting that leaves of the pear seedlings suffered from oxidative injury. Superoxide dismutase (SOD and catalase (CAT activities quickly responded by increasing when the pear seedlings were subjected to salinity stress. Total protein content in leaves of the seedlings was restrained by salinity stress, whereas ascorbate content increased. Salinity stress reduced glutathione content once the birch-leaved pear seedlings were exposed to a low level (50 or 100 mmol/L of NaCl, whereas a high level (150 or 200 mmol/L NaCl of salinity stress stimulated the accumulation of glutathione. Salinity stress increased the accumulation of Na+, Cl-, K+ and Mg2+ in the seedlings, but reduced Ca2+ levels and the ratio of other ions to Na+ except K+/Na+ under 50 mmol/L NaCl conditions. This suggests that leaves of birch-leaved pear seedlings possess the capacity for salt exclusion only under 50 mmol/L NaCl conditions, and Ca2+ does not play a fundamental role as a secondary messenger under salinity stress conditions.

  2. POLLEN MORPHOLOGY OF CROCUS L.(IRIDACEAE) IN BULGARIA

    OpenAIRE

    UZUNDZHALIEVA KATYA SPASOVA; Maria POPOVA TODOROVA

    2012-01-01

    The pollen of the wild species from the genus Crocus L., spread in Bulgaria has been analyzed. The investigations, made by light microscope show that the pollen of these species is spherical in shape and round in outlines, comparatively big. These morphological characteristics of the pollen of the wild Bulgarian Crocuses define it as a primitive one [6]. The Scanning Electron Microscope investigations, made by Beug [1], established two types of pollen morphology. The results of our investigat...

  3. Pollen-stigma interactions in Brassica. IV. Structural reorganization in the pollen grains during hydration.

    Science.gov (United States)

    Elleman, C J; Dickinson, H G

    1986-02-01

    With the aid of osmium tetroxide vapour, dry pollen and pollen at various stages of hydration has been fixed anhydrously for examination with the transmission electron microscope (TEM). In addition to establishing features characteristic of grains at different states of hydration, this technique has enabled the detection of a superficial layer investing both the exine and the pollen coating. This layer, some 10 nm in depth, binds both lanthanum and Alcian Blue and is shown to be the first component of the pollen grain to make contact with the stigmatic pellicle. The use of vapour fixation has also rendered it possible to chart the passage of water into the pollen grains with great accuracy, for each level of hydration displays a strikingly different cytoplasmic organization. For example, dry pollen is characterized by the presence of unusual structures at the protoplast surface and large numbers of spherical fibrillar bodies, whilst the protoplast of hydrating pollen is conspicuously stratified and contains a peripheral layer of membranous cisternae, subjacent to which is a fibrillar matrix derived from the spherical bodies found in the dry grains. Vapour-fixed, fully hydrated pollen resembles conventionally fixed grains. The pollen coating appears electron-translucent after anhydrous fixation and contains discrete, slightly rounded bodies some 50 nm in diameter. The uptake of water by grains on the stigma is accompanied by conspicuous structural changes in this layer for, after a short period in contact with the papillar surface, the spherical bodies rapidly disappear and the coat becomes electron-opaque. Close examination of this 'converted' coating reveals the presence of membranous vesicles and other structural components.

  4. Diversity and conservation in maize pollen: Phenotypes and transcripts

    Science.gov (United States)

    In addition to its crucial role in seed production, pollen serves as a vector for gene flow between plant populations. Recently, pollen was identified as a mechanism for introduction of transgenes into non-transgenic populations. To investigate the genetic basis for pollen fitn...

  5. Saccharomyces cerevisiae Fermentation Effects on Pollen: Archaeological Implications

    Directory of Open Access Journals (Sweden)

    Crystal A. Dozier

    2016-03-01

    Full Text Available Pollen is the reproductive agent of flowering plants; palynology is utilized by archaeologists because sporopollenin, a major component in the exine of pollen grains, is resistant to decay and morphologically distinctive. Wine, beer, and mead have been identified in the archaeological record by palynological assessment due to indicator species or due to a pollen profile similar to that recovered from honey, a common source of sugar in a variety of fermented beverages. While most palynologists have assumed that pollen grains are resistant to alcoholic fermentation, a recent study in food science implies that pollen is a yeast nutrient because pollen-enriched meads produce more alcohol. The experiment presented here explores the potential distortion of the pollen record through fermentation by brewing a traditional, pollen-rich mead with Saccharomyces cerevisiae. In this experiment, the pollen grains did not undergo any discernible morphological changes nor were distorted in the pollen profile. Any nutrition that the yeast garners from the pollen therefore leaves sporopollenin intact. These results support palynological research on residues of alcoholic beverages and confirms that the fermentation process does not distort the pollen profile of the original substance. The paper concludes with the potential and limits of palynological study to assess fermentation within the archaeological record.

  6. Pollen Biology of Ornamental Ginger (Hedychium spp. J. Koenig)

    Science.gov (United States)

    An improved in vitro pollen germination assay was developed to assess the viability of stored Hedychium pollen. The effect of polyethylene glycol (PEG) (10, 15, and 20% w/v) on pollen germination and tube growth was evaluated for H. longicornutum and two commercial Hedychium cultivars, ‘Orange Brush...

  7. Pollen morphology of the genus Begonia in Africa

    NARCIS (Netherlands)

    Berg, van den R.G.

    1985-01-01

    The morphology of the pollen grains of African Begonias is described, leading to the recognition of 15 pollen types. These pollen types are assumed to constitute natural units produced by evolution and the main purpose of this study has been to reconstruct the course of evolution and to apply the re

  8. Effects of NO2 and ozone on pollen allergenicity

    Directory of Open Access Journals (Sweden)

    Ulrike eFrank

    2016-02-01

    Full Text Available This mini-review summarizes the available data of the air pollutants NO2 and ozone on allergenic pollen from different plant species, focusing on potentially allergenic components of the pollen, such as allergen content, protein release, IgE-binding or protein modification. Various in vivo and in vitro studies on allergenic pollen are shown and discussed.

  9. The relationship of storage and viability of Lily pollen

    NARCIS (Netherlands)

    Rhee, H.K.; Lim, Jin Hee; Cho, Hae Ryong; Tuyl, van J.M.

    2003-01-01

    The study was conducted to estimate the pollen viability of eight lily genotypes and optimum storage conditions. Pollen viability was assessed by in vitro germination, FCR (Fluorochromatic raction) test and fruit set test. Pollen grains were stored in the dark chamber where the temperature was maint

  10. 7 CFR 201.78 - Pollen control for hybrids.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pollen control for hybrids. 201.78 Section 201.78... REGULATIONS Additional Requirements for the Certification of Plant Materials of Certain Crops § 201.78 Pollen... branches, or any combination thereof, shedding pollen. (c) Sorghum. Shedders in the seed parent, at any...

  11. Immunochemical identification of gelsolin in maize pollen

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gelsolin is a representative of a type of actin-binding proteins (ABPs) universally found in eukaryotes. It plays role in nucleation, capping and severing of actin filaments in vitro. In our experiment, gelsolin was purified from pig plasma and the polyclonal antibodies against it were prepared. The crude extracts of maize pollen were immunodetected by Western-blotting with polyclonal antibody and monoclonal antibody respectively. The immunodetection results show that gelsolin exists in maize pollen and its molecular weight is about 91 ku, similar to that of gelsolin found in animal tissues.

  12. Pollen lipidomics: lipid profiling exposes a notable diversity in 22 allergenic pollen and potential biomarkers of the allergic immune response.

    Directory of Open Access Journals (Sweden)

    Mohamed Elfatih H Bashir

    Full Text Available BACKGROUND/AIM: Pollen grains are the male gametophytes that deliver sperm cells to female gametophytes during sexual reproduction of higher plants. Pollen is a major source of aeroallergens and environmental antigens. The pollen coat harbors a plethora of lipids that are required for pollen hydration, germination, and penetration of the stigma by pollen tubes. In addition to proteins, pollen displays a wide array of lipids that interact with the human immune system. Prior searches for pollen allergens have focused on the identification of intracellular allergenic proteins, but have largely overlooked much of the extracellular pollen matrix, a region where the majority of lipid molecules reside. Lipid antigens have attracted attention for their potent immunoregulatory effects. By being in close proximity to allergenic proteins on the pollen surface when they interact with host cells, lipids could modify the antigenic properties of proteins. METHODOLOGY/PRINCIPAL FINDINGS: We performed a comparative pollen lipid profiling of 22 commonly allergenic plant species by the use of gas chromatography-mass spectroscopy, followed by detailed data mining and statistical analysis. Three experiments compared pollen lipid profiles. We built a database library of the pollen lipids by matching acquired pollen-lipid mass spectra and retention times with the NIST/EPA/NIH mass-spectral library. We detected, identified, and relatively quantified more than 106 lipid molecular species including fatty acids, n-alkanes, fatty alcohols, and sterols. Pollen-derived lipids stimulation up-regulate cytokines expression of dendritic and natural killer T cells co-culture. CONCLUSIONS/SIGNIFICANCE: Here we report on a lipidomic analysis of pollen lipids that can serve as a database for identifying potential lipid antigens and/or novel candidate molecules involved in allergy. The database provides a resource that facilitates studies on the role of lipids in the

  13. Effect of hydrogen fluoride on pollen germination and pollen tube growth in Prunus avium L. cv. Royal Ann

    Energy Technology Data Exchange (ETDEWEB)

    Facteau, T.J.; Wang, S.Y.; Rowe, K.E.

    1973-05-01

    Increased fluoride (F) fumigation levels resulted in decrease in percent Royal Ann pollen germination and pollen tube growth. As dose (hour x concentration in ..mu.. gF/m/sup 3/) increased, Van pollen tube growth in vivo decreased. A linear relationship between increased dose and fluoride residue in the flowers was shown. 14 references, 5 figures.

  14. Recent pollen spectra from the deciduous and coniferous-deciduous forests of Northeastern Minnesota: a study in pollen dispersal

    NARCIS (Netherlands)

    Janssen, C.R.

    1966-01-01

    Pollen samples were taken along nine transects across local vegetational belts bordering bogs or ponds in overall deciduous and coniferous-deciduous forest regions. Three types of pollen rain are distinguished: local, extralocal, and regional. Local pollen rain is derived from plants that grow at or

  15. Pollen calendar of the city of Salamanca (Spain). Aeropalynological analysis for 1981-1982 and 1991-1992.

    Science.gov (United States)

    Hernández Prieto, M; Lorente Toledano, F; Romo Cortina, A; Dávila González, I; Laffond Yges, E; Calvo Bullón, A

    1998-01-01

    We report a study on the contents of airborne pollen in the city of Salamanca (Spain) aimed at establishing a pollen calendar for the city for the yearly periods of maximum concentrations, relating these with quantifiable atmospheric variables over two two-year periods with an interval of 10 years between them: 1981-82 and 1991-92. The pollen was captured with Burkard spore-traps, based on Hirst's volumetric method. Determinations were made daily and were used to make preparations, previously stained with basic fuscin, for study under light microscopy at x 1,000 magnification. 946 preparations were analyzed, corresponding to the same number of days distributed over 150 weeks of the periods studied. The results afforded the identification of 48 different types of pollen grain: Grasses (Poaceae), Olea europea (olive), Quercus rotundifolia (Holm-oak), other Quercus spp. (Q. pyrenaica, Q. suber, Q. faginea, etc.), Cupressaceae (Cupressus sempervivens, C. arizonica, Juniperus communis etc.), Plantago (Plantago lanceolata, Plantago media, etc.), Pinaceae (Pinus communis, Abies alba, etc.), Rumex sp. (osier), Urtica dioica (nettle), Parietaria (Parietaria officinalis, P. judaica), Chenopodio-Amaranthaceae (Chenopodium sp., Amaranthus sp., Salsola kali, etc.), Artemisia vulgaris (Artemisia), other Compositae (Taraxacum officinalis, Hellianthus sp. etc.), Castanea sativa (Chestnut), Ligustrum sp. (privet), Betula sp. (birch), Alnus sp. (common alder), Fraxinus sp (ash), Populus sp. (poplar), Salix sp. (willow), Ulmus sp. (elm), Platanus sp. (plantain, plane), Carex sp. (sweet flag), Erica sp. (common heather), Leguminosae or Fabaceae:--Papillionaceae (Medicago sp.; Cercis sp., Robina sp.)--Cesalpinoideae Acacia sp. (Acacia),--Mimosoideae: Sophora japonica, Umbelliferae (Foeniculum sp., Cirsium sp., etc.), Centaurea sp., Cistus sp. (rock rose), Typha sp (bulrush), Mirtaceae (Myrtus communis), Juglans regia (Walnut), Galium verum, Filipendula sp. (spirea/drop wort), Rosaceae

  16. Golgi 58K-like protein in pollens and pollen tubes of Lilium davidii

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In animal cells, Golgi apparatus is located near the microtubule organizing center (MTOC) and its position is determined partly by 58K protein. By sodium dodecyl-sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immuno-blotting methods, a 58K-like protein has been found in pollen grains and pollen tubes of Lilium davidii. Its molecular weight is very similar to that of the 58K protein of animal cells. By immunofluorescence labeling, under a confocal laser scanning microscope (CLSM), the animal 58K antibody revealed a punctate staining in pollen grains and pollen tubes, which is consistent with the distribution of Golgi apparatus in plant cells. In addition, immuno-gold labeling and transmission electron microscopy showed that the 58K-like protein bound mainly to the membrane of vesicles-like structure near Golgi apparatus. This is the first demonstration of the 58K-like protein in plant cells.

  17. Moth outbreaks alter root-associated fungal communities in subarctic mountain birch forests.

    Science.gov (United States)

    Saravesi, Karita; Aikio, Sami; Wäli, Piippa R; Ruotsalainen, Anna Liisa; Kaukonen, Maarit; Huusko, Karoliina; Suokas, Marko; Brown, Shawn P; Jumpponen, Ari; Tuomi, Juha; Markkola, Annamari

    2015-05-01

    Climate change has important implications on the abundance and range of insect pests in forest ecosystems. We studied responses of root-associated fungal communities to defoliation of mountain birch hosts by a massive geometrid moth outbreak through 454 pyrosequencing of tagged amplicons of the ITS2 rDNA region. We compared fungal diversity and community composition at three levels of moth defoliation (intact control, full defoliation in one season, full defoliation in two or more seasons), replicated in three localities. Defoliation caused dramatic shifts in functional and taxonomic community composition of root-associated fungi. Differentially defoliated mountain birch roots harbored distinct fungal communities, which correlated with increasing soil nutrients and decreasing amount of host trees with green foliar mass. Ectomycorrhizal fungi (EMF) abundance and richness declined by 70-80 % with increasing defoliation intensity, while saprotrophic and endophytic fungi seemed to benefit from defoliation. Moth herbivory also reduced dominance of Basidiomycota in the roots due to loss of basidiomycete EMF and increases in functionally unknown Ascomycota. Our results demonstrate the top-down control of belowground fungal communities by aboveground herbivory and suggest a marked reduction in the carbon flow from plants to soil fungi following defoliation. These results are among the first to provide evidence on cascading effects of natural herbivory on tree root-associated fungi at an ecosystem scale.

  18. Adhesive Through-Reinforcement Improves the Fracture Toughness of a Laminated Birch Wood Composite

    Directory of Open Access Journals (Sweden)

    Wenchang He

    2017-01-01

    Full Text Available In this paper we test the hypothesis that adhesive through-reinforcement in combination with glass-fibre reinforcement of adhesive bond lines will significantly improve the fracture toughness of a laminated birch wood composite. We test this hypothesis using a model composite consisting of perforated veneer that allowed a polyurethane adhesive to penetrate and reinforce veneers within the composite. Model composite specimens were tested for mode I fracture properties, and scanning electron microscopy was used to examine the microstructure of fracture surfaces. Our results clearly show that through-reinforcement, and also reinforcing adhesive bond lines with glass-fibre, significantly improved fracture toughness of the birch wood composite. Our results also indicate that improvements in fracture toughness depended on the level of reinforcement. Improvements in fracture toughness were related to the ability of the reinforcement to arrest crack development during fracture testing and the fibre bridging effect of glass-fibre in adhesive bond lines. We conclude that through-reinforcement is an effective way of improving the fracture toughness of laminated wood composites, but further research is needed to develop practical ways of creating such reinforcement in composites that more closely resemble commercial products.

  19. Pollen size strongly correlates with stigma depth among Pedicularis species

    Institute of Scientific and Technical Information of China (English)

    Xiang-Ping Wang; Wen-Bin Yu; Shi-Guo Sun; Shuang-Quan Huang

    2016-01-01

    Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a positive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species (Orobanchaceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin’s functional hypothesis between pollen size and stigma depth.

  20. Airborne Pollen Grains in Zonguldak,Turkey,2001-2002

    Institute of Scientific and Technical Information of China (English)

    Ayse KAPLAN

    2004-01-01

    The variation in airborne pollen concentration of the Zonguldak region, Turkey was studied for two consecutive years 2001-2002 using a Durham sampler. During this period, a total of 61 304 pollen grains belonging to 43 taxa were recorded. Of these 43 taxa, 26 belonged to arboreal and 17 to nonarboreal plants. The main pollen types were Pinaceae, Populus, Carpinus, Betula, Corylus, Fagus orientalis,Castanea sativa, Alnus glutinosa, Quercus, Cupressaceae, Chenopodiaceae and Gramineae, representing 96.7% of the pollen spectrum. Pollen concentration reached the highest level in March.

  1. Extensive pollen flow but few pollen donors and high reproductive variance in an extremely fragmented landscape.

    Directory of Open Access Journals (Sweden)

    Rafael G Albaladejo

    Full Text Available Analysing pollen movement is a key to understanding the reproductive system of plant species and how it is influenced by the spatial distribution of potential mating partners in fragmented populations. Here we infer parameters related to levels of pollen movement and diversity of the effective pollen cloud for the wind-pollinated shrub Pistacia lentiscus across a highly disturbed landscape using microsatellite loci. Paternity analysis and the indirect KinDist and Mixed Effect Mating models were used to assess mating patterns, the pollen dispersal kernel, the effective number of males (N(ep and their relative individual fertility, as well as the existence of fine-scale spatial genetic structure in adult plants. All methods showed extensive pollen movement, with high rates of pollen flow from outside the study site (up to 73-93%, fat-tailed dispersal kernels and large average pollination distances (δ = 229-412 m. However, they also agreed in detecting very few pollen donors (N(ep = 4.3-10.2 and a large variance in their reproductive success: 70% of males did not sire any offspring among the studied female plants and 5.5% of males were responsible for 50% of pollinations. Although we did not find reduced levels of genetic diversity, the adult population showed high levels of biparental inbreeding (14% and strong spatial genetic structure (S(p = 0.012, probably due to restricted seed dispersal and scarce safe sites for recruitment. Overall, limited seed dispersal and the scarcity of successful pollen donors can be contributing to generate local pedigrees and to increase inbreeding, the prelude of genetic impoverishment.

  2. Changes to airborne pollen counts across Europe.

    Directory of Open Access Journals (Sweden)

    Chiara Ziello

    Full Text Available A progressive global increase in the burden of allergic diseases has affected the industrialized world over the last half century and has been reported in the literature. The clinical evidence reveals a general increase in both incidence and prevalence of respiratory diseases, such as allergic rhinitis (common hay fever and asthma. Such phenomena may be related not only to air pollution and changes in lifestyle, but also to an actual increase in airborne quantities of allergenic pollen. Experimental enhancements of carbon dioxide (CO[Formula: see text] have demonstrated changes in pollen amount and allergenicity, but this has rarely been shown in the wider environment. The present analysis of a continental-scale pollen data set reveals an increasing trend in the yearly amount of airborne pollen for many taxa in Europe, which is more pronounced in urban than semi-rural/rural areas. Climate change may contribute to these changes, however increased temperatures do not appear to be a major influencing factor. Instead, we suggest the anthropogenic rise of atmospheric CO[Formula: see text] levels may be influential.

  3. The Beauty and Biology of Pollen.

    Science.gov (United States)

    Clay-Poole, Scott T.; Slesnick, Irwin L.

    1983-01-01

    Describes: basic features of pollen grains (shapes, apertures, layering of wall, exine sculpturing); strategies for pollination (anemophily--wind transported, zoophily--animal transported); and the structures specialized for each process. Gives instructions for using scanning electron microscope photographs and for collecting, identifying, and…

  4. [Eosinophilic gastroenteritis caused by bee pollen sensitization].

    Science.gov (United States)

    Puente, S; Iñíguez, A; Subirats, M; Alonso, M J; Polo, F; Moneo, I

    1997-05-10

    A 34-year-old Spanish woman with a lifelong history of seasonal rhinoconjunctivitis and honey intolerance (pyrosis and abdominal pain) developed, 3 weeks after starting ingestion of bee pollen, astenia, anorexia, abdominal pain, diarrhoea, peripheral blood hypereosinophilia and elevated serum total IgE levels. A duodenal biopsy showed eosinophilic infiltration of the mucosal layer. Other causes of hypereosinophilia were not found. Repeated parasitological stool studies, as well as a duodenal aspirate showed negative results. Symptoms, hypereosinophilia and elevated IgE levels resolved after bee pollen ingestion was stopped. This is a typical case of eosinophilic gastroenteritis by ingestion of bee pollen in a woman with intolerance to honey bee, because the patient fulfilled the usual diagnostic criteria: gastrointestinal symptoms were present, eosinophilic infiltration of the digestive tract was demonstrated by biopsy, no eosinophilic infiltration of other organs was found and the presence of parasites was excluded. Honey intolerance and/or bee pollen administration should be considered as a cause of eosinophilic gastroenteritis.

  5. Proteomic analyses of apoplastic proteins from germinating Arabidopsis thaliana pollen.

    Science.gov (United States)

    Ge, Weina; Song, Yun; Zhang, Cuijun; Zhang, Yafang; Burlingame, Alma L; Guo, Yi

    2011-12-01

    Pollen grains play important roles in the reproductive processes of flowering plants. The roles of apoplastic proteins in pollen germination and in pollen tube growth are comparatively less well understood. To investigate the functions of apoplastic proteins in pollen germination, the global apoplastic proteins of mature and germinated Arabidopsis thaliana pollen grains were prepared for differential analyses by using 2-dimensional fluorescence difference gel electrophoresis (2-D DIGE) saturation labeling techniques. One hundred and three proteins differentially expressed (p value≤0.01) in pollen germinated for 6h compared with un-germination mature pollen, and 98 spots, which represented 71 proteins, were identified by LC-MS/MS. By bioinformatics analysis, 50 proteins were identified as secreted proteins. These proteins were mainly involved in cell wall modification and remodeling, protein metabolism and signal transduction. Three of the differentially expressed proteins were randomly selected to determine their subcellular localizations by transiently expressing YFP fusion proteins. The results of subcellular localization were identical with the bioinformatics prediction. Based on these data, we proposed a model for apoplastic proteins functioning in pollen germination and pollen tube growth. These results will lead to a better understanding of the mechanisms of pollen germination and pollen tube growth.

  6. Pollen processing behavior of Heliconius butterflies: a derived grooming behavior.

    Science.gov (United States)

    Hikl, Anna-Laetitia; Krenn, Harald W

    2011-01-01

    Pollen feeding behaviors Heliconius and Laparus (Lepidoptera: Nymphalidae) represent a key innovation that has shaped other life history traits of these neotropical butterflies. Although all flower visiting Lepidoptera regularly come in contact with pollen, only Heliconius and Laparus butterflies actively collect pollen with the proboscis and subsequently take up nutrients from the pollen grains. This study focused on the behavior of pollen processing and compared the movement patterns with proboscis grooming behavior in various nymphalid butterflies using video analysis. The proboscis movements of pollen processing behavior consisted of a lengthy series of repeated coiling and uncoiling movements in a loosely coiled proboscis position combined with up and down movements and the release of saliva. The proboscis-grooming behavior was triggered by contamination of the proboscis in both pollen feeding and non-pollen feeding nymphalid butterflies. Proboscis grooming movements included interrupted series of coiling and uncoiling movements, characteristic sideways movements, proboscis lifting, and occasionally full extension of the proboscis. Discharge of saliva was more pronounced in pollen feeding species than in non-pollen feeding butterfly species. We conclude that the pollen processing behavior of Heliconius and Laparus is a modified proboscis grooming behavior that originally served to clean the proboscis after contamination with particles.

  7. Using the pollen viability and morphology for fluoride pollution biomonitoring.

    Science.gov (United States)

    Malayeri, Behrooz Eshghi; Noori, Mitra; Jafari, Mehrana

    2012-06-01

    The methods using plants for biomonitoring of air and soil quality are simple, cheap, and fast and can supplement the classical physicochemical methods. In this study, biological pollen characterization of some collected legume species from an aluminum smelter area in Iran (IRALCO) was carried out to determine the actual value of pollen as a bioindicator of the effects of soil and atmospheric pollution. Young buds and flowers of six legumes (Cercis siliquastrum L., Medicago sativa L., Robinia pseudoacacia L., Melilotus officinalis (L.) lam, Trifolium repens L., and Sophora alopecuroides L.) in polluted and control plants were removed and compared. Studies of light and electron microscopic preparation showed some abnormalities during pollen development in affect of fluoride pollution. The viability of pollen grains estimated by staining with acetocarmine shows sharp differences in smearing advanced pollen grains from abnormal ones. Except M. officinalis, the pollen grains of C. siliquastrum, M. sativa, R. pseudoacacia, T. repens, and S. alopecuroides in polluted areas showed light, partial, or no staining with acetocarmine, whereas almost all of the control ones clearly stained. Observation of the pollen grains by light microscopy and scanning electron microscopy showed the significant effect of fluoride on shapes and sizes of pollen grains. The stimulation and inhibition of these pollen characteristics depend on the pollen species as well as on the pollutant and its concentration. Therefore, pollen grains provide essential information on biological impact of pollutants and they are good candidates for biomonitoring the atmospheric and edaphic pollutions.

  8. SURVEY OF AIRBORNE POLLEN IN HUBEI PROVINCE OF CHINA

    Institute of Scientific and Technical Information of China (English)

    Guang-hui Liu; Rong-fei Zhu; Wei Zhang; Wen-jing Li; Zhong-xi Wang; Huan Chen

    2008-01-01

    Objective To study the genera and seasonal distribution of airborne pollen in Hubei province of China,and its relationship with pollinosis.Methods From November 2003 to October 2004,an airborne pollen investigation was performed in 16 chosen areas in 12 cities of Hubei province using gravity sedimentation technique.Meanwhile,univalent skin prick tests of pollens were performed and the invasion season was studied on 2 300 patients with pollinosis.Among them,352 eases underwent the airway responsiveness measurements,and the correlation between airway responsiveness and results of pollen count was analyzed.Results A total of 61 pollen genera were observed and 257 520 pollens were collected.The peak of airborne pollen distribution occurred in two seasons each year:spring (March and April) and autumn (from August to October).The attack of pollinosis corresponded to the peak of pollen distribution.There was a significantly negative relationship between the provocation dose causing a 20% decrease of forced expiratory volume in one second (FEV1) from baseline and airborne pollen concentration (r=-0.6829,P<0.05).Conclusion This study provides useful information for airborne pollen epidemiology of Hubei province,and it provides important insights to clinical prevention,diagnosis,and treatment of pollen-related allergic diseases.

  9. Mismatch in aeroallergens and airborne grass pollen concentrations

    Science.gov (United States)

    Plaza, M. P.; Alcázar, P.; Hernández-Ceballos, M. A.; Galán, C.

    2016-11-01

    An accurate estimation of the allergen concentration in the atmosphere is essential for allergy sufferers. The major cause of pollinosis all over Europe is due to grass pollen and Phl p 5 has the highest rates of sensitization (>50%) in patients with grass pollen-induced allergy. However, recent research has shown that airborne pollen does not always offer a clear indicator of exposure to aeroallergens. This study aims to evaluate relations between airborne grass pollen and Phl p 5 concentrations in Córdoba (southern Spain) and to study how meteorological parameters influence these atmospheric records. Monitoring was carried out from 2012 to 2014. Hirst-type volumetric spore trap was used for pollen collection, following the protocol recommended by the Spanish Aerobiology Network (REA). Aeroallergen sampling was performed using a low-volume cyclone sampler, and allergenic particles were quantified by ELISA assay. Besides, the influence of main meteorological factors on local airborne pollen and allergen concentrations was surveyed. A significant correlation was observed between grass pollen and Phl p 5 allergen concentrations during the pollen season, but with some sporadic discrepancy episodes. The cumulative annual Pollen Index also varied considerably. A significant correlation has been obtained between airborne pollen and minimum temperature, relative humidity and precipitation, during the three studied years. However, there is no clear relationship between allergens and weather variables. Our findings suggest that the correlation between grass pollen and aeroallergen Phl p 5 concentrations varies from year-to-year probably related to a complex interplay of meteorological variables.

  10. Considerations About Pollen Used for the Production of Allergen Extracts.

    Science.gov (United States)

    Codina, Rosa; Crenshaw, Rodger C; Lockey, Richard F

    2015-01-01

    Pollen is a biological product obtained to manufacture tree, weed, and grass allergen extracts, used to diagnose and treat allergies. Genetic and environmental factors affect the composition of pollen, e.g., the plant varieties from which pollen are obtained, weather, and levels of air pollution during plant growth. Therefore, appropriate guidelines and training of personnel to perform the activities associated with pollen are essential to produce appropriate allergen extracts. Various regulatory institutions, which vary in different countries, including the Food and Drug Administration (FDA) in the USA, control how such products should be produced. For example, the FDA regulates the manufacturing of pollen extracts but not the quality of the pollen used to prepare them, relying on each manufacturer to set its own standards to do so. To the contrary, European regulatory agencies, including the European Medicines Agency, control both the quality of the pollen and the manufacturing process to produce pollen extracts. Regulatory agencies, allergen manufacturers, scientific institutions, and pollen collection entities should collaborate to develop and implement guidelines appropriate for worldwide use for both the collection and processing of pollen raw materials. This article provides an overview of the subject of pollen for use in allergen extracts.

  11. Deep-water Oligocene pollen record from South China Sea

    Institute of Scientific and Technical Information of China (English)

    WU Guoxuan; QIN Jungan; MAO Shaozhi

    2003-01-01

    Leg 184 of ODP recovered a record of deep- water sediments spanning the past 32.8 Ma from the South China Sea (SCS). The sediments of the Oligocene (32.8 - 23.8 Ma) at Site 1148 contain relatively abundant fossil pollen. The pollen analysis at Site 1148 has established the first pollen assemblage sequence of deep-water Oligocene in the China Sea. The pollen assemblages of the Oligocene are dominated by montane conifer tree pollen. The abundances of broad-leaved tree pollen are lower in the assemblages. Both of the montane conifer and broad-leaved tree pollen groups include mainly tropical-subtropical components. The pollen of cold and drought-enduring plants is present in lower content. The distinct change in pollen assemblage sequence of deep-water Oligocene of the SCS occurred at 32.0 Ma, indicative of an important shift of the Oligocene climate in the SCS region. The characteristics of the pollen flora of the deep-water Oligocene indicate the tropical montane rainforest and lowland rainforest developed on the areas around the SCS before 32.0 Ma, reflecting the warm and wet climatic condition. In the pollen flora of the Oligocene after 32.0 Ma, the temperate montane conifer and cool and drought-en- during deciduous tree taxa remarkably increased, indicating that the climate in the SCS region became comparatively cool and dry.

  12. The morphology of pollen presenter and polymorphism of pollen grains Taraxacum officinale F. H. Wigg.

    Directory of Open Access Journals (Sweden)

    Elżbieta Weryszko-Chmielewska

    2012-12-01

    Full Text Available The study of the structure of the pollen presenter of Taraxacum officinale and morphology of pollen grains was conducted based on plant material sampled from three different sites. One of them was a forest meadow situated away from the city, and the other two were located in the city centre of Lublin. Light and electron scanning microscopy were used in the study. The pollen presenter in Taraxacum officinale occurs at the upper part of the style situated over the androecium and on the outer part of the stigma. Numerous unicellular trichomes are found on the entire surface of the epidermis of the presenter. The function of the presenter consists in transferring pollen grains above the androecium and corolla petals. Its activity does not stop after pollen release from anthers. Taraxacum pollen grains represent the Crepis - type. Most frequently, they are tricolporate, radially symmetric and isopolar. In terms of the size, they are included in medium-sized grains. In the material examined, many deformed and asymmetric grains were observed, though they were marked by high viability at the level of 96.5-99%. Grains with the largest average lengths of the equatorial and polar axes were found in plants sampled from the meadow situated out of town. In the plant material from all sites, grains with disturbances of the external structure occurred.

  13. Specific immunotherapy for common grass pollen allergies: pertinence of a five grass pollen vaccine.

    Science.gov (United States)

    Moingeon, Philippe; Hrabina, Maud; Bergmann, Karl-Christian; Jaeger, Siegfried; Frati, Franco; Bordas, Véronique; Peltre, Gabriel

    2008-01-01

    Patients throughout Europe are concomitantly exposed to multiple pollens from distinct Pooideae species. Given the overlap in pollination calendars and similar grain morphology, it is not possible to identify which grass species are present in the environment from pollen counts. Furthermore, neither serum IgE reactivity nor skin prick testing allow the identification of which grass species are involved in patient sensitisation. Due to their high level of amino acid sequence homology (e.g., >90% for group 1, 55-80% for group 5), significant cross-immunogenicity is observed between allergens from Pooideae pollens. Nevertheless, pollen allergens also contain species-specific T or B cell epitopes, and substantial quantitative differences exist in allergen (e.g., groups 1 and 5) composition between pollens from distinct grass species. In this context, a mixture of pollens from common and well-characterised Pooideae such as Anthoxanthum odoratum, Dactylis glomerata, Lolium perenne, Phleum pratense and Poa pratensis is suitable for immunotherapy purposes because (1) it has been validated, both in terms of safety and efficacy, by established clinical practice; (2) it reflects natural exposure and sensitisation conditions; (3) it ensures a consistent and well-balanced composition of critical allergens, thus extending the repertoire of T and B cell epitopes present in the vaccine.

  14. Pectic arabinan side chains are essential for pollen cell wall integrity during pollen development.

    Science.gov (United States)

    Cankar, Katarina; Kortstee, Anne; Toonen, Marcel A J; Wolters-Arts, Mieke; Houbein, Rudolf; Mariani, Celestina; Ulvskov, Peter; Jorgensen, Bodil; Schols, Henk A; Visser, Richard G F; Trindade, Luisa M

    2014-05-01

    Pectin is a complex polysaccharide and an integral part of the primary plant cell wall and middle lamella, contributing to cell wall mechanical strength and cell adhesion. To understand the structure-function relationships of pectin in the cell wall, a set of transgenic potato lines with altered pectin composition was analysed. The expression of genes encoding enzymes involved in pectin acetylation, degradation of the rhamnogalacturonan backbone and type and length of neutral side chains, arabinan and galactan in particular, has been altered. Upon crossing of different transgenic lines, some transgenes were not transmitted to the next generation when these lines were used as a pollen donor, suggesting male sterility. Viability of mature pollen was severely decreased in potato lines with reduced pectic arabinan, but not in lines with altered galactan side chains. Anthers and pollen of different developmental stages were microscopically examined to study the phenotype in more detail. Scanning electron microscopy of flowers showed collapsed pollen grains in mature anthers and in earlier stages cytoplasmic protrusions at the site of the of kin pore, eventually leading to bursting of the pollen grain and leaking of the cytoplasm. This phenomenon is only observed after the microspores are released and the tapetum starts to degenerate. Timing of the phenotype indicates a role for pectic arabinan side chains during remodelling of the cell wall when the pollen grain is maturing and dehydrating.

  15. In vitro pollen germination and pollen viability in passion fruit (Passiflora spp.

    Directory of Open Access Journals (Sweden)

    Taliane Leila Soares

    2013-12-01

    Full Text Available The use of Passiflora species for ornamental purposes has been recently developed, but little is known about pollen viability and the potential for crossing different species. The objective of this study was to evaluate the pollen viability of six Passiflora species collected from different physiological stages of development through in vitro germination and histochemical analysis using dyes. The pollen was collected in three stages (pre-anthesis, anthesis and post-anthesis. Three compositions of culture medium were used to evaluate the in vitro germination, and two dyes (2,3,5-triphenyltetrazolium chloride, or TTC, and Lugol's solution were used for the histochemical analysis. The culture medium containing 0.03% Ca(NO3 4H2O, 0.02% of Mg(SO4 .7H2O, 0.01% of KNO3, 0,01% of H3BO3, 15% sucrose, and 0.8% agar, pH 7.0, showed a higher percentage of pollen grains germinated. Anthesis is the best time to collect pollen because it promotes high viability and germination. The Lugol's solution and TTC dye overestimated the viability of pollen, as all accessions showed high viability indices when compared with the results obtained in vitro.

  16. Pollen flow of wheat under natural conditions in the Huanghuai River Wheat Region, China

    OpenAIRE

    Sun, Ai-Qing; Zhang, Chun-Qing; Wu, Cheng-Lai; Gao, Qing-Rong

    2015-01-01

    The transgenic pollen spread is the main pathway of transgenic plant gene flow. The maximum distance of pollen dispersal (horizontal), the spatial dynamics of pollen movement (vertical), and the patterns of pollen dispersal are important considerations in biosafety assessments of genetically modified crops. To evaluate wheat (Triticum aestivum) pollen dispersal, we measured the pollen suspension velocity and analyzed pollen dispersal patterns under natural conditions in the Huanghuai River wh...

  17. Pollen features of hazelnut (Corylus avellana L. from different habitats

    Directory of Open Access Journals (Sweden)

    Natalia Nikolaieva

    2014-04-01

    Full Text Available The aim of this work was to study general morphological characteristics of pollen grains of Corylus avellana L. Seven samples of pollen were investigated. Samples were collected from different habitats in Ukraine – from botanical gardens (Kyiv, Kamianets-Podilskyi and natural habitats (Kyiv region, Kamianets-Podilskyi, and Sumy region. We studied such morphological traits of pollen grains as length of polar and equatorial axes, diameter of pores, and shape of the pollen grain (elongation index. Analysis of morphological characters of pollen was carried out using electron microscope. Comparison of data was performed with the data of the base polleninfo.org. During research the differences in these parameters were marked. Pollen grains of C. avellana are generally isopolar, from suboblate to oblate or oblate-spheroidal, and contain 3 pores. The article contains an attempt to explain the size variations noted for the pollen collected from different habitats.

  18. Aerobiology of Juniperus Pollen in Oklahoma, Texas, and New Mexico

    Science.gov (United States)

    Levetin, Estelle; Bunderson, Landon; VandeWater, Pete; Luvall, Jeff

    2014-01-01

    Pollen from members of the Cupressaceae are major aeroallergens in many parts of the world. In the south central and southwest United States, Juniperus pollen is the most important member of this family with J. ashei (JA) responsible for severe winter allergy symptoms in Texas and Oklahoma. In New Mexico, pollen from J. monosperma (JM) and other Juniperus species are important contributors to spring allergies, while J. pinchotii (JP) pollinates in the fall affecting sensitive individuals in west Texas, southwest Oklahoma and eastern New Mexico. Throughout this region, JA, JM, and JP occur in dense woodland populations. Generally monitoring for airborne allergens is conducted in urban areas, although the source for tree pollen may be forested areas distant from the sampling sites. Improved pollen forecasts require a better understanding of pollen production at the source. The current study was undertaken to examine the aerobiology of several Juniperus species at their source areas for the development of new pollen forecasting initiatives.

  19. Monitoring, modelling and forecasting of the pollen season

    DEFF Research Database (Denmark)

    Scheifinger, Helfried; Belmonte, Jordina; Buters, Jeroen

    2013-01-01

    The section about monitoring covers the development of phenological networks, remote sensing of the season cycle of the vegetation, the emergence of the science of aerobiology and, more specifically, aeropalynology, pollen sampling instruments, pollen counting techniques, applications...... of aeropalynology in agriculture and the European Pollen Information System. Three data sources are directly related with aeropalynology: phenological observations, pollen counts and remote sensing of the vegetation activity. The main future challenge is the assimilation of these data streams into numerical pollen...... forecast systems. Over the last decades consistent monitoring efforts of various national networks have created a wealth of pollen concentration time series. These constitute a nearly untouched treasure, which is still to be exploited to investigate questions concerning pollen emission, transport...

  20. Dominating IgE-binding epitope of Bet v 1, the major allergen of birch pollen, characterized by X-ray crystallography and site-directed mutagenesis

    DEFF Research Database (Denmark)

    Spangfort, Michael D; Mirza, Osman; Ipsen, Henrik

    2003-01-01

    approach to the engineering of allergen molecules with reduced IgE binding. In this study, we describe the identification and modification of a human IgE-binding epitope based on the crystal structure of Bet v 1 in complex with the BV16 Fab' fragment. The epitope occupies approximately 10% of the molecular...

  1. The safety and efficacy of subcutaneous birch pollen immunotherapy - a one-year, randomised, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Poulsen, L K; Jacobi, H H;

    2002-01-01

    was conducted as a clustered regimen and was performed in a specialist unit. Symptom scores from nose, eyes, and lungs, and use of oral and topical antihistamines, beta-2-agonists, and oral corticosteroids were recorded daily during the season of 2000. Sensitivity to allergen provocation in skin, conjunctiva...... antihistamines (P

  2. Crystallization and preliminary X-ray analysis of birch-pollen allergen Bet v 1 in complex with a murine monoclonal IgG Fab' fragment

    DEFF Research Database (Denmark)

    Spangfort, M D; Mirza, Osman Asghar; Gajhede, M

    1999-01-01

    The human type I allergic response is characterized by the presence of allergen-specific serum immunoglobulin E (IgE). Allergen-mediated cross-linking of receptor-bound IgE on the surface of mast cells and circulating basophils triggers the release of mediators, resulting in the development of th......, with unit-cell parameters a = 91.65, b = 99.14, c = 108.90 A, alpha = 105.7, beta = 98.32, gamma = 97.62 degrees, and diffract to 2.9 A resolution when analyzed at 100 K using synchrotron-generated X--rays....

  3. The blocking activity of birch pollen-specific immunotherapy-induced IgG4 is not qualitatively superior to that of other IgG subclasses

    DEFF Research Database (Denmark)

    Ejrnaes, Anne M; Bødtger, Uffe; Larsen, Jørgen N;

    2004-01-01

    blocking activity was found in the purified IgG4 fraction. There was no significant difference in the binding avidities (1/K(d)) measured in the two IgG fractions. Thus, it appears that SIT-induced specific IgG4 contributes to the IgG blocking of allergen binding to IgE in a simple quantitative manner...

  4. Drought, pollen and nectar availability, and pollination success.

    Science.gov (United States)

    Waser, Nickolas M; Price, Mary V

    2016-06-01

    Pollination success of animal-pollinated flowers depends on rate of pollinator visits and on pollen deposition per visit, both of which should vary with the pollen and nectar "neighborhoods" of a plant, i.e., with pollen and nectar availability in nearby plants. One determinant of these neighborhoods is per-flower production of pollen and nectar, which is likely to respond to environmental influences. In this study, we explored environmental effects on pollen and nectar production and on pollination success in order to follow up a surprising result from a previous study: flowers of Ipomopsis aggregata received less pollen in years of high visitation by their hummingbird pollinators. A new analysis of the earlier data indicated that high bird visitation corresponded to drought years. We hypothesized that drought might contribute to the enigmatic prior result if it decreases both nectar and pollen production: in dry years, low nectar availability could cause hummingbirds to visit flowers at a higher rate, and low pollen availability could cause them to deposit less pollen per visit. A greenhouse experiment demonstrated that drought does reduce both pollen and nectar production by I. aggregata flowers. This result was corroborated across 6 yr of variable precipitation and soil moisture in four unmanipulated field populations. In addition, experimental removal of pollen from flowers reduced the pollen received by nearby flowers. We conclude that there is much to learn about how abiotic and biotic environmental drivers jointly affect pollen and nectar production and availability, and how this contributes to pollen and nectar neighborhoods and thus influences pollination success.

  5. Assessment of pollen reward and pollen availability in Solanum stramoniifolium and Solanum paniculatum for buzz-pollinating carpenter bees.

    Science.gov (United States)

    Burkart, A; Schlindwein, C; Lunau, K

    2014-03-01

    The two widespread tropical Solanum species S. paniculatum and S. stramoniifolium are highly dependent on the visits of large bees that pollinate the flowers while buzzing them. Both Solanum species do not offer nectar reward; the rewarding of bees is thus solely dependent on the availability of pollen. Flower visitors are unable to visually assess the amount of pollen, because the pollen is hidden in poricidal anthers. In this study we ask whether and how the amount of pollen determines the attractiveness of flowers for bees. The number of pollen grains in anthers of S. stramoniifolium was seven times higher than in S. paniculatum. By contrast, the handling time per five flowers for carpenter bees visiting S. paniculatum was 3.5 times shorter than of those visiting S. stramoniifolium. As a result foraging carpenter bees collected a similar number of pollen grains per unit time on flowers of both species. Experimental manipulation of pollen availability by gluing the anther pores showed that the carpenter bees were unable to detect the availability of pollen by means of chemical cues before landing and without buzzing. Our study shows that the efficiency of pollen collecting on S. paniculatum is based on large inflorescences with short between-flower search times and short handling time of individual flowers, whereas that of S. stramoniifolium relies on a large amount of pollen per flower. Interestingly, large carpenter bees are able to adjust their foraging behaviour to drastically different strategies of pollen reward in otherwise very similar plant species.

  6. Role of macrophage migration inhibitory factor (MIF in pollen-induced allergic conjunctivitis and pollen dermatitis in mice.

    Directory of Open Access Journals (Sweden)

    Yuka Nagata

    Full Text Available Pollen is a clinically important airborne allergen and one of the major causes of allergic conjunctivitis. A subpopulation of patients with atopic dermatitis (AD are also known to have exacerbated skin eruptions on the face, especially around the eyelids, after contact with pollen. This pollen-induced skin reaction is now known as pollen dermatitis. Macrophage migration inhibitory factor (MIF is a pluripotent cytokine that plays an essential role in allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including AD. In this study, MIF knockout (KO, MIF transgenic (Tg and WT littermate mice were immunized with ragweed (RW pollen or Japanese cedar (JC pollen and challenged via eye drops. We observed that the numbers of conjunctiva- and eyelid-infiltrating eosinophils were significantly increased in RW and JC pollen-sensitized MIF Tg compared with WT mice or MIF KO mice. The mRNA expression levels of eotaxin, interleukin (IL-5 and IL-13 were increased in pollen-sensitized eyelid skin sites of MIF Tg mice. An in vitro analysis revealed that high eotaxin expression was induced in dermal fibroblasts by MIF combined with stimulation of IL-4 or IL-13. This eotaxin expression was inhibited by the treatment with CD74 siRNA in fibroblasts. These findings indicate that MIF can induce eosinophil accumulation in the conjunctiva and eyelid dermis exposed to pollen. Therefore, targeted inhibition of MIF might result as a new option to control pollen-induced allergic conjunctivitis and pollen dermatitis.

  7. Considerations for the preparation of peat samples for palynology, and for the counting of pollen and non-pollen palynomorphs

    Directory of Open Access Journals (Sweden)

    F.M. Chambers

    2011-09-01

    Full Text Available Peat deposits are valuable archives for studying palaeoclimate, the history of local and regional vegetation, and human impact. The most widely applied laboratory analytical technique has been palynology (pollen analysis, which is often limited to the study of pollen and a few easily recognisable spores; however, a variety of other microfossils can be studied in peat deposits and can provide information on past environmental conditions. Among the so-called non-pollen palynomorphs (NPPs are fungal and algal spores that can be used as indicators for local hydrological changes and trophic conditions. This article provides an overview of aspects to consider and sample preparation methods for pollen, spores and other non-pollen palynomorph microfossils in peat deposits; advice on aids to pollen identification and counting; and a brief guide to the range of NPPs that can be counted from prepared subfossil-pollen microslides.

  8. Influence of Nitrogen Availability on Growth of Two Transgenic Birch Species Carrying the Pine GS1a Gene

    Directory of Open Access Journals (Sweden)

    Vadim G. Lebedev

    2017-01-01

    Full Text Available An alternative way to increase plant productivity through the use of nitrogen fertilizers is to improve the efficiency of nitrogen utilization via genetic engineering. The effects of overexpression of pine glutamine synthetase (GS gene and nitrogen availability on growth and leaf pigment levels of two Betula species were studied. Untransformed and transgenic plants of downy birch (B. pubescens and silver birch (B. pendula were grown under open-air conditions at three nitrogen regimes (0, 1, or 10 mM for one growing season. The transfer of the GS1a gene led to a significant increase in the height of only two transgenic lines of nine B. pubescens, but three of five B. pendula transgenic lines were higher than the controls. In general, nitrogen supply reduced the positive effect of the GS gene on the growth of transgenic birch plants. No differences in leaf pigment levels between control and transgenic plants were found. Nitrogen fertilization increased leaf chlorophyll content in untransformed plants but its effect on most of the transgenic lines was insignificant. The results suggest that birch plants carrying the GS gene use nitrogen more efficiently, especially when growing in nitrogen deficient soil. Transgenic lines were less responsive to nitrogen supply in comparison to wild-type plants.

  9. Influence of Nitrogen Availability on Growth of Two Transgenic Birch Species Carrying the Pine GS1a Gene

    Science.gov (United States)

    Lebedev, Vadim G.; Kovalenko, Nina P.; Shestibratov, Konstantin A.

    2017-01-01

    An alternative way to increase plant productivity through the use of nitrogen fertilizers is to improve the efficiency of nitrogen utilization via genetic engineering. The effects of overexpression of pine glutamine synthetase (GS) gene and nitrogen availability on growth and leaf pigment levels of two Betula species were studied. Untransformed and transgenic plants of downy birch (B. pubescens) and silver birch (B. pendula) were grown under open-air conditions at three nitrogen regimes (0, 1, or 10 mM) for one growing season. The transfer of the GS1a gene led to a significant increase in the height of only two transgenic lines of nine B. pubescens, but three of five B. pendula transgenic lines were higher than the controls. In general, nitrogen supply reduced the positive effect of the GS gene on the growth of transgenic birch plants. No differences in leaf pigment levels between control and transgenic plants were found. Nitrogen fertilization increased leaf chlorophyll content in untransformed plants but its effect on most of the transgenic lines was insignificant. The results suggest that birch plants carrying the GS gene use nitrogen more efficiently, especially when growing in nitrogen deficient soil. Transgenic lines were less responsive to nitrogen supply in comparison to wild-type plants. PMID:28067821

  10. Academic Success for Students of Color . . . At What Cost? The Importance of School Context at Birch High School

    Science.gov (United States)

    Chambers, Terah T. Venzant; Tabron, Lolita A.

    2013-01-01

    Kiara, an African American rising freshman, has aspirations to become a medical doctor. She enrolls at Birch High School because of the reputation of the principal, Mr. Brown, whose vision for academic excellence permeates every corner of the school. Kiara graduates from high school with top honors, but realizes her success may have come at a…

  11. Assessing the Potential Stem Growth and Quality of Yellow Birch Prior to Restoration: A Case Study in Eastern Canada

    Directory of Open Access Journals (Sweden)

    Alexis Achim

    2013-09-01

    Full Text Available Past silvicultural treatments have resulted in the high-grading mixed temperate forests of Québec, Canada. Despite recognition of this issue, the low occurrence of yellow birch (Betula alleghaniensis Britton within current stands raises questions about the potential of the species to grow and eventually constitute a high-quality forest resource. The objective of this study was to assess this potential using tree characteristics, forest structure and additional site and climatic conditions as predictors. A total of 145 trees were sampled in two areas located in the same bioclimatic zone. Lower-Saguenay-Charlevoix was chosen as an area where a restoration plan could be implemented, whereas Portneuf was selected as a reference. We used nonlinear mixed models to investigate which environmental factors are likely to influence the radial growth and stem quality of yellow birch sample trees. Our results suggest that topographic and climatic conditions, as well as the competitive environment of the trees, are important factors to consider in the evaluation of yellow birch production. Despite the limited occurrence of yellow birch, the potential for growth and quality was high in the Lower-Saguenay-Charlevoix area. For equivalent topographic, climatic, and competitive environment conditions, there was no significant difference in either radial growth or stem quality with Portneuf. We suggest that the economic interest of producing high quality timber should be used to justify the implementation of a restoration strategy in the Lower-Saguenay-Charlevoix area.

  12. Birch Bark Dry Extract by Supercritical Fluid Technology: Extract Characterisation and Use for Stabilisation of Semisolid Systems

    Directory of Open Access Journals (Sweden)

    Markus Armbruster

    2017-03-01

    Full Text Available Triterpene compounds like betulin, betulinic acid, erythrodiol, oleanolic acid and lupeol are known for many pharmacological effects. All these substances are found in the outer bark of birch. Apart from its pharmacological effects, birch bark extract can be used to stabilise semisolid systems. Normally, birch bark extract is produced for this purpose by extraction with organic solvents. Employing supercritical fluid technology, our aim was to develop a birch bark dry extract suitable for stabilisation of lipophilic gels with improved properties while avoiding the use of toxic solvents. With supercritical carbon dioxide, three different particle formation methods from supercritical solutions have been tested. First, particle deposition was performed from a supercritical solution in an expansion chamber. Second, the Rapid Expansion of Supercritical Solutions (RESS method was used for particle generation. Third, a modified RESS-procedure, forming the particles directly into the thereby gelated liquid, was developed. All three methods gave yields from 1% to 5.8%, depending on the techniques employed. The triterpene composition of the three extracts was comparable: all three gave more stable oleogels compared to the use of an extract obtained by organic solvent extraction. Characterizing the rheological behaviour of these gels, a faster gelling effect was seen together with a lower concentration of the extract required for the gel formation with the supercritical fluid (SCF-extracts. This confirms the superiority of the supercritical fluid produced extracts with regard to the oleogel forming properties.

  13. Hive-stored pollen of honey bees: many lines of evidence are consistent with pollen preservation, not nutrient conversion.

    Science.gov (United States)

    Anderson, Kirk E; Carroll, Mark J; Sheehan, Tim; Lanan, Michele C; Mott, Brendon M; Maes, Patrick; Corby-Harris, Vanessa

    2014-12-01

    Honey bee hives are filled with stored pollen, honey, plant resins and wax, all antimicrobial to differing degrees. Stored pollen is the nutritionally rich currency used for colony growth and consists of 40-50% simple sugars. Many studies speculate that prior to consumption by bees, stored pollen undergoes long-term nutrient conversion, becoming more nutritious 'bee bread' as microbes predigest the pollen. We quantified both structural and functional aspects associated with this hypothesis using behavioural assays, bacterial plate counts, microscopy and 454 amplicon sequencing of the 16S rRNA gene from both newly collected and hive-stored pollen. We found that bees preferentially consume fresh pollen stored for 96 h. The estimated microbe to pollen grain surface area ratio was 1:1 000 000 indicating a negligible effect of microbial metabolism on hive-stored pollen. Consistent with these findings, hive-stored pollen grains did not appear compromised according to microscopy. Based on year round 454 amplicon sequencing, bacterial communities of newly collected and hive-stored pollen did not differ, indicating the lack of an emergent microbial community co-evolved to digest stored pollen. In accord with previous culturing and 16S cloning, acid resistant and osmotolerant bacteria like Lactobacillus kunkeei were found in greatest abundance in stored pollen, consistent with the harsh character of this microenvironment. We conclude that stored pollen is not evolved for microbially mediated nutrient conversion, but is a preservative environment due primarily to added honey, nectar, bee secretions and properties of pollen itself.

  14. Phenolic compounds and expression of 4CL genes in silver birch clones and Pt4CL1a lines.

    Science.gov (United States)

    Sutela, Suvi; Hahl, Terhi; Tiimonen, Heidi; Aronen, Tuija; Ylioja, Tiina; Laakso, Tapio; Saranpää, Pekka; Chiang, Vincent; Julkunen-Tiitto, Riitta; Häggman, Hely

    2014-01-01

    A small multigene family encodes 4-coumarate:CoA ligases (4CLs) catalyzing the CoA ligation of hydroxycinnamic acids, a branch point step directing metabolites to a flavonoid or monolignol pathway. In the present study, we examined the effect of antisense Populus tremuloides 4CL (Pt4CL1) to the lignin and soluble phenolic compound composition of silver birch (Betula pendula) Pt4CL1a lines in comparison with non-transgenic silver birch clones. The endogenous expression of silver birch 4CL genes was recorded in the stems and leaves and also in leaves that were mechanically injured. In one of the transgenic Pt4CL1a lines, the ratio of syringyl (S) and guaiacyl (G) lignin units was increased. Moreover, the transcript levels of putative silver birch 4CL gene (Bp4CL1) were reduced and contents of cinnamic acid derivatives altered. In the other two Pt4CL1a lines changes were detected in the level of individual phenolic compounds. However, considerable variation was found in the transcript levels of silver birch 4CLs as well as in the concentration of phenolic compounds among the transgenic lines and non-transgenic clones. Wounding induced the expression of Bp4CL1 and Bp4CL2 in leaves in all clones and transgenic lines, whereas the transcript levels of Bp4CL3 and Bp4CL4 remained unchanged. Moreover, minor changes were detected in the concentrations of phenolic compounds caused by wounding. As an overall trend the wounding decreased the flavonoid content in silver birches and increased the content of soluble condensed tannins. The results indicate that by reducing the Bp4CL1 transcript levels lignin composition could be modified. However, the alterations found among the Pt4CL1a lines and the non-transgenic clones were within the natural variation of silver birches, as shown in the present study by the clonal differences in the transcripts levels of 4CL genes, soluble phenolic compounds and condensed tannins.

  15. Phenolic compounds and expression of 4CL genes in silver birch clones and Pt4CL1a lines.

    Directory of Open Access Journals (Sweden)

    Suvi Sutela

    Full Text Available A small multigene family encodes 4-coumarate:CoA ligases (4CLs catalyzing the CoA ligation of hydroxycinnamic acids, a branch point step directing metabolites to a flavonoid or monolignol pathway. In the present study, we examined the effect of antisense Populus tremuloides 4CL (Pt4CL1 to the lignin and soluble phenolic compound composition of silver birch (Betula pendula Pt4CL1a lines in comparison with non-transgenic silver birch clones. The endogenous expression of silver birch 4CL genes was recorded in the stems and leaves and also in leaves that were mechanically injured. In one of the transgenic Pt4CL1a lines, the ratio of syringyl (S and guaiacyl (G lignin units was increased. Moreover, the transcript levels of putative silver birch 4CL gene (Bp4CL1 were reduced and contents of cinnamic acid derivatives altered. In the other two Pt4CL1a lines changes were detected in the level of individual phenolic compounds. However, considerable variation was found in the transcript levels of silver birch 4CLs as well as in the concentration of phenolic compounds among the transgenic lines and non-transgenic clones. Wounding induced the expression of Bp4CL1 and Bp4CL2 in leaves in all clones and transgenic lines, whereas the transcript levels of Bp4CL3 and Bp4CL4 remained unchanged. Moreover, minor changes were detected in the concentrations of phenolic compounds caused by wounding. As an overall trend the wounding decreased the flavonoid content in silver birches and increased the content of soluble condensed tannins. The results indicate that by reducing the Bp4CL1 transcript levels lignin composition could be modified. However, the alterations found among the Pt4CL1a lines and the non-transgenic clones were within the natural variation of silver birches, as shown in the present study by the clonal differences in the transcripts levels of 4CL genes, soluble phenolic compounds and condensed tannins.

  16. Analysis of three types of triterpenoids in tetraploid white birches (Betula platyphylla Suk.) and selection of plus trees

    Institute of Scientific and Technical Information of China (English)

    Sui Wang; Hui Zhao; Jing Jiang; Guifeng Liu; Chuanping Yang

    2015-01-01

    Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the outer bark of white birch. In this study, we used ultrasound-assisted extraction (UAE) to extract triterpenoids from birch bark rapidly and with high efficiency. Using high performance liquid chro-matography (HPLC), three types of triterpenoids were separated and detected. We examined the differences among triterpenoids extracted from diploid versus tetra-ploid white birch. Then, we used factor analysis to screen out tetraploid white birches with comprehensively excel-lent performance. The results indicate that the optimum conditions for extraction include the use of ethanol as an extraction solvent, a solid-to-liquid ratio of 0.1 g/10 ml, ultrasonic power set at 100 W, a temperature of 60 ?C and an extraction time of 15 min. A reversed-phase C18 col-umn (4.6 mm 9 250 mm 9 5 lm) with a column tem-perature of 30 ?C and the mobile phase composed of A (acetonitrile) and B (0.1% aqueous phosphoric acid, v/v) at a flow rate of 0.5 ml/min were used, and the detection wavelength was 195 nm. No significant difference was observed between diploid and tetraploid white birch in terms of the content of three types of triterpenoids (at a confidence level of 0.05). As triterpenoid content, height, and DBH (diameter at breast height) are strongly interre-lated, we used factor analysis to evaluate all individuals, and we screened out six plus trees with excellent com-prehensive characters.

  17. Ultrastructure and germination of Vitis vinifera cv. Loureiro pollen.

    Science.gov (United States)

    Abreu, I; Costa, I; Oliveira, M; Cunha, M; de Castro, R

    2006-08-01

    The cultivar Loureiro of Vitis vinifera is one of the most economically important, recommended in almost the totality of the Região Demarcada dos Vinhos Verdes. In vineyards, the grape productivity of this cultivar is normal while in others it is extremely low. The aim of this work was to study the morphology and germination of Vitis vinifera cv. Loureiro pollen with high and low productivity. The pollen grain was examined under light, transmission and scanning electron microscopy. Typically V. vinifera pollen present three furrows but in the cultivar Loureiro we found tricolporated and acolporated (without furrows or pores) pollen grains. Both pollen types present generative and vegetative cells with the usual aspect and a dense cytoplasm rich in organelles. In the acolporated pollen a continuous exine layer and an irregular intine layer were observed. Differences were found in the starch accumulation, since only in tricolporated pollen abundant plastids filled with numerous starch granules were observed. To determine the causes of the low productivity of this cultivar we tested pollen viability by the fluorochromatic reaction and pollen germinability by in vitro assays. We observed that the acolporated pollen grain is viable, but no germination was recorded.

  18. [Allergic responses to date palm and pecan pollen in Israel].

    Science.gov (United States)

    Waisel, Y; Keynan, N; Gil, T; Tayar, D; Bezerano, A; Goldberg, A; Geller-Bernstein, C; Dolev, Z; Tamir, R; Levy, I

    1994-03-15

    Date palm (Phoenix dactylifera) and pecan (Carya illinoensis) trees are commonly planted in Israel for fruit, for shade, or as ornamental plants. Pollen grains of both species are allergenic; however, the extent of exposure to such pollen and the incidence of allergic response have not been studied here. We therefore investigated skin-test responses to pollen extracts of 12 varieties of palm and 9 of pecan in 705 allergic patients living in 3 cities and 19 rural settlements. Sensitivity to the pollen extracts of both species was much higher among residents of rural than of urban communities. Moreover, there was a definite relationship between the abundance of these trees in a region and the incidence of skin responders to their pollen. Sensitivity was frequent in settlements rich in these 2 species, such as those with nearby commercial date or pecan plantations. In general, sensitivity to date pollen extracts was lower than to pecan. However, differences in skin responses to pollen extracts of various clones were substantiated. Air sampling revealed that pollen pollution decreased considerably with distance from the trees. At approximately 100 m from a source concentrations of airborne pollen were low. Since planting of male palm and pecan trees in population centers would increase pollen pollution, it should be avoided.

  19. The language of GABA in pollen tube growth and guidance

    Institute of Scientific and Technical Information of China (English)

    Guanghui YU; Yan CHEN

    2008-01-01

    The achievement of double fertilization in higher plants requires the successful transport of sperm cells to the female gametes, the ovules. Pollen tubes, the tubular structure protruding from pollens, carrying the sperms play an important role in this process. How a pollen tube precisely guides its direction to gain its goal is of mystery. Previous investigation indicated that mul-tiple signal clues from the pistils function as the route signs to regulate the pathway of pollen tube growth. Among the signal clues, γ-aminobutyric acid (GABA) seems to be universal. Its gradient concentration has been found both in tobacco and Arabidopsis pollen tube guid-ance. In the communication of pollens and pistils, what on earth GABA tells pollen tubes is of great interest. The GABA receptors on the pollen membrane are thought to be the hinge in the language conversation. In this review, the mechanism of GABA gradient formation is investigated. The possible GABA receptor on the pollen membrane is examined and its function is discussed. To decipher the possible language of GABA in pollen tube growth and guidance, multiple methods are needed. The combination of transcriptome and proteomics assay is expected to unveil the secret.

  20. Genomic expression profiling of mature soybean (Glycine max pollen

    Directory of Open Access Journals (Sweden)

    Singh Mohan B

    2009-03-01

    Full Text Available Abstract Background Pollen, the male partner in the reproduction of flowering plants, comprises either two or three cells at maturity. The current knowledge of the pollen transcriptome is limited to the model plant systems Arabidopsis thaliana and Oryza sativa which have tri-cellular pollen grains at maturity. Comparative studies on pollen of other genera, particularly crop plants, are needed to understand the pollen gene networks that are subject to functional and evolutionary conservation. In this study, we used the Affymetrix Soybean GeneChip® to perform transcriptional profiling on mature bi-cellular soybean pollen. Results Compared to the sporophyte transcriptome, the soybean pollen transcriptome revealed a restricted and unique repertoire of genes, with a significantly greater proportion of specifically expressed genes than is found in the sporophyte tissue. Comparative analysis shows that, among the 37,500 soybean transcripts addressed in this study, 10,299 transcripts (27.46% are expressed in pollen. Of the pollen-expressed sequences, about 9,489 (92.13% are also expressed in sporophytic tissues, and 810 (7.87% are selectively expressed in pollen. Overall, the soybean pollen transcriptome shows an enrichment of transcription factors (mostly zinc finger family proteins, signal recognition receptors, transporters, heat shock-related proteins and members of the ubiquitin proteasome proteolytic pathway. Conclusion This is the first report of a soybean pollen transcriptional profile. These data extend our current knowledge regarding regulatory pathways that govern the gene regulation and development of pollen. A comparison between transcription factors up-regulated in soybean and those in Arabidopsis revealed some divergence in the numbers and kinds of regulatory proteins expressed in both species.

  1. Soil Chemical and Microbial Properties in a Mixed Stand of Spruce and Birch in the Ore Mountains (Germany—A Case Study

    Directory of Open Access Journals (Sweden)

    Karoline Schua

    2015-06-01

    Full Text Available A major argument for incorporating deciduous tree species in coniferous forest stands is their role in the amelioration and stabilisation of biogeochemical cycles. Current forest management strategies in central Europe aim to increase the area of mixed stands. In order to formulate statements about the ecological effects of mixtures, studies at the stand level are necessary. In a mixed stand of Norway spruce (Picea abies (L. Karst. and silver birch (Betula pendula Roth in the Ore Mountains (Saxony, Germany, the effects of these two tree species on chemical and microbial parameters in the topsoil were studied at one site in the form of a case study. Samples were taken from the O layer and A horizon in areas of the stand influenced by either birch, spruce or a mixture of birch and spruce. The microbial biomass, basal respiration, metabolic quotient, pH-value and the C and N contents and stocks were analysed in the horizons Of, Oh and A. Significantly higher contents of microbial N were observed in the Of and Oh horizons in the birch and in the spruce-birch strata than in the stratum containing only spruce. The same was found with respect to pH-values in the Of horizon and basal respiration in the Oh horizon. Compared to the spruce stratum, in the birch and spruce-birch strata, significantly lower values were found for the contents of organic C and total N in the A horizon. The findings of the case study indicated that single birch trees have significant effects on the chemical and microbial topsoil properties in spruce-dominated stands. Therefore, the admixture of birch in spruce stands may distinctly affect nutrient cycling and may also be relevant for soil carbon sequestration. Further studies of these functional aspects are recommended.

  2. Breeding increases the efficacy of Chondrostereum purpureum in the sprout control of birch.

    Directory of Open Access Journals (Sweden)

    Leena Hamberg

    Full Text Available We tested whether the pairing of selected isolates could be used to increase the efficiency of a decay fungus Chondrostereum purpureum (Pers. Ex Fr. Pouzar to control hardwood sprouting in Finland. We paired C. purpureum strains efficient in sprout control or highly active in laccase production, and tested the efficacy of their progeny in spout control experiments. This procedure resulted in a strain with an efficacy superior to that of the parental strains. The mortality of birch (Betula pendula Roth. and B. pubescens Ehrh. 1 cm in stump diameter was 78%, 56% and 9% for the best progeny, the best parental strain and the control, respectively. Mortality was only slightly higher for B. pendula than for B. pubescens but no significant differences were found between the number or maximum height of stump sprouts. Our results showed that cross breeding of this decay fungus is a good alternative in attempts to produce efficient biocontrol agents against hardwood sprouting.

  3. 桦木板材的快速干燥%Rapid Drying of Birch Lumber

    Institute of Scientific and Technical Information of China (English)

    李增超; 邱增处; 杨庆; 雷亚芳

    2001-01-01

    采用阶段连续升温干燥基准,增加热湿处理工艺,用炉气间接加热木材干燥窑对不同厚度桦木锯材进行快速窑干工艺试验,实践证明不但干燥周期缩短30%,且提高了干燥质量,易于操作。%Rapid kiln-drying experiment on birch lumber of kiln in whichphased continuous heating drying schedule and the conditioning technology are adopted.It has been proved in practice that such kiln-drying technology can not only shorten the drying period by 30% but also improve drying quality as well as be operated easily.

  4. Regularizations of the Euler product representation for zeta functions and the Birch--Swinnerton-Dyer conjecture

    CERN Document Server

    Fujimoto, Minoru

    2007-01-01

    We consider a variant expression to regularize the Euler product representation of the zeta functions, where we mainly apply to that of the Riemann zeta function in this paper. The regularization itself is identical to that of the zeta function of the summation expression, but the non-use of the M\\"oebius function enable us to confirm a finite behavior of residual terms which means an absence of zeros except for the critical line. Same technique can be applied to the $L$-function associated to the elliptic curve, and we can deal with the Taylor expansion at the pole in critical strip which is deeply related to the Birch--Swinnerton-Dyer conjecture.

  5. Nickel and Copper Toxicity and Plant Response Mechanisms in White Birch (Betula papyrifera).

    Science.gov (United States)

    Theriault, Gabriel; Nkongolo, Kabwe

    2016-08-01

    Nickel (Ni) and copper (Cu) are the most prevalent metals found in the soils in the Greater Sudbury Region (Canada) because of smelting emissions. The main objectives of the present study were to (1) determine the toxicity of nickel (Ni) and copper (Cu) at different doses in Betula papyrifera (white birch), (2) Characterize nickel resistance mechanism, and (3) assess segregating patterns for Ni and Cu resistance in B. papyrifera populations. This study revealed that B. papyrifera is resistant to Ni and Cu concentrations equivalent to the levels reported in metal-contaminated stands in the GSR. Resistant genotypes (RG) accumulate Ni in roots but not in leaves. Moderately susceptible (MSG) and susceptible genotypes (SG) show a high level of Ni translocation to leaves. Gene expression analysis showed differential regulation of genes in RG compared to MSG and SG. Analysis of segregation patterns suggests that resistance to Ni and Cu is controlled by single recessive genes.

  6. Intrinsically microporous polyesters from betulin - toward renewable materials for gas separation made from birch bark.

    Science.gov (United States)

    Jeromenok, Jekaterina; Böhlmann, Winfried; Antonietti, Markus; Weber, Jens

    2011-11-15

    Betulin, an abundant triterpene, can be extracted from birch bark and can be used as a renewable monomer in the synthesis of microporous polyesters. Cross-linked networks and hyperbranched polymers are accessible by an A(2) + B(3) reaction, with betulin being the A(2) monomer and B(3) being a trifunctional acid chloride. Reaction of betulin with a diacid dichloride results in linear, soluble polyesters. The present communication proves that the polyreaction follows the classic schemes of polycondensation reactions. The resulting polymers are analyzed with regard to their micro-porosity by gas sorption, NMR spectroscopy, and X-ray scattering methods. The polymers feature intrinsic microporosity, having ultrasmall pores, which makes them candidates for gas separation membranes, e.g., for the separation of CO(2) from N(2) .

  7. Effects of carbon dioxide concentration and nutrition on photosynthetic functions of white birch seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S. [Lakehead Univ., Thunder Bay, ON (Canada). Faculty of Forestry and the Forest Environment; Dang, Q.L. [Lakehead Univ., Thunder Bay, ON (Canada). Faculty of Forest and the Forest Environment; Chinese Academy of Sciences, Beijing (China). Inst. of Botany, Laboratory of Quantitative Vegetation Ecology

    2006-11-15

    Increases in atmospheric carbon dioxide (CO{sub 2}) can impact photosynthesis and dry mass production of plants. This study investigated the physiological responses of white birch seedlings to elevated carbon dioxide (CO{sub 2}) at low and high supplies of nitrogen (N), phosphorus (P) and potassium (K). A 2-way factorial experiment was carried out with birch seedlings grown for 4 months in environment-controlled greenhouses. Elevated CO{sub 2} enhanced maximal carboxylation rate and photosynthetically active radiation-saturated electron transport rates were measured after 2.5 and 3.5 months of treatment, as well as actual photochemical efficiency and photosynthetic linear electron transport to carboxylation. Net photosynthetic rate increases were observed as well as increases in photosynthetic water use efficiency (WUE); photosynthetic N efficiency and P efficiency. Stomatal conductance, transpiration rate and the fraction of total photosynthetic linear electron transport partitioned to oxygenation were reduced. Low nutrient availability decreased net photosynthetic rates, WUE, and triose phosphate utilization. However, photosynthetic linear electron transport and N use efficiency increased. There were significant interactive effects of CO{sub 2} and nutrition over time, with evidence of photosynthetic up-regulation in response to elevated CO{sub 2} in seedlings receiving high nutrition. Photosynthetic depression in response to low nutrient availability was attributed to biochemical limitation rather than stomatal limitation. Elevated CO{sub 2} reduced leaf N concentration in seedlings receiving low nutrition, but had no significant effect on leaf P or K concentrations. High nutrient availability generally increased area-based leaf N, P and K concentrations but had negligible effects on K after 2.5 months of treatment. Results suggested that increases in electron partitioning to photorespiration in response to low nutrient availability may be related to

  8. Chemical and physical characterization of emissions from birch wood combustion in a wood stove

    Science.gov (United States)

    Hedberg, Emma; Kristensson, Adam; Ohlsson, Michael; Johansson, Christer; Johansson, Per-Åke; Swietlicki, Erik; Vesely, Vaclav; Wideqvist, Ulla; Westerholm, Roger

    The purpose of this study was to characterize the emissions of a large number of chemical compounds emitted from birch wood combustion in a wood stove. Birch wood is widely used as fuel in Swedish household appliances. The fuel load was held constant during six experiments. Particles dust, range 30-330 for the former and 0.8±0.15 for the latter. The source profile of common elements emitted from wood burning differed from that found on particles at a street-level site or in long-distance transported particles. The ratio toluene/benzene in this study was found to be in the range 0.2-0.7, which is much lower than the ratio 3.6±0.5 in traffic exhaust emissions. Formaldehyde and acetone were the most abundant compounds among the volatile ketones and aldehydes. The emission factor varied between 180-710 mg/kg wood for formaldehyde and 5-1300 mg/kg wood for acetone. Of the organic acids analyzed (3,4,5)-trimethoxy benzoic acid was the most abundant compound. Of the PAHs reported, fluorene, phenanthrene, anthracene, fluoranthene and pyrene contribute to more than 70% of the mass of PAH. Of the elements analyzed, K and Si were the most abundant elements, having emission factors of 27 and 9 mg/kg wood, respectively. Although fluoranthene has a toxic equivalence factor of 5% of benzo(a)pyrene (B(a)P), it can be seen that the toxic potency of fluoranthene in wood burning emissions is of the same size as B(a)P. This indicates that the relative carcinogenic potency contribution of fluoranthene in wood smoke would be about 40% of B(a)P.

  9. Genome sequence of dwarf birch (Betula nana) and cross-species RAD markers.

    Science.gov (United States)

    Wang, Nian; Thomson, Marian; Bodles, William J A; Crawford, Robert M M; Hunt, Harriet V; Featherstone, Alan Watson; Pellicer, Jaume; Buggs, Richard J A

    2013-06-01

    New sequencing technologies allow development of genome-wide markers for any genus of ecological interest, including plant genera such as Betula (birch) that have previously proved difficult to study due to widespread polyploidy and hybridization. We present a de novo reference genome sequence assembly, from 66× short read coverage, of Betula nana (dwarf birch) - a diploid that is the keystone woody species of subarctic scrub communities but of conservation concern in Britain. We also present 100 bp PstI RAD markers for B. nana and closely related Betula tree species. Assembly of RAD markers in 15 individuals by alignment to the reference B. nana genome yielded 44-86k RAD loci per individual, whereas de novo RAD assembly yielded 64-121k loci per individual. Of the loci assembled by the de novo method, 3k homologous loci were found in all 15 individuals studied, and 35k in 10 or more individuals. Matching of RAD loci to RAD locus catalogues from the B. nana individual used for the reference genome showed similar numbers of matches from both methods of RAD locus assembly but indicated that the de novo RAD assembly method may overassemble some paralogous loci. In 12 individuals hetero-specific to B. nana 37-47k RAD loci matched a catalogue of RAD loci from the B. nana individual used for the reference genome, whereas 44-60k RAD loci aligned to the B. nana reference genome itself. We present a preliminary study of allele sharing among species, demonstrating the utility of the data for introgression studies and for the identification of species-specific alleles.

  10. Fluorescent dye particles as pollen analogues for measuring pollen dispersal in an insect-pollinated forest herb.

    Science.gov (United States)

    Van Rossum, Fabienne; Stiers, Iris; Van Geert, Anja; Triest, Ludwig; Hardy, Olivier J

    2011-03-01

    In flowering plants, pollen dispersal is often the major contributing component to gene flow, hence a key parameter in conservation genetics and population biology. A cost-effective method to assess pollen dispersal consists of monitoring the dispersal of fluorescent dyes used as pollen analogues. However, few comparisons between dye dispersal and realized pollen dispersal have been performed to validate the method. We investigated pollen dispersal in two small populations of the insect-pollinated herb Primula elatior from urban forest fragments using direct (paternity analyses based on microsatellite DNA markers) and indirect (fluorescent dyes) methods. We compared these methods using two approaches, testing for the difference between the distance distributions of observed dispersal events and estimating parameters of a dispersal model, and related these results to dye dispersal patterns in three large populations. Dye and realized (based on paternity inference) pollen dispersal showed exponential decay distributions, with 74.2-94.8% of the depositions occurring at pollen dispersal distributions. The best-fitting parameters characterizing the dye dispersal model were consistent with those obtained for realized pollen dispersal. Hence, the fluorescent dye method may be considered as reliable to infer realized pollen dispersal for forest herbs such as P. elatior. However, our simulations reveal that large sample sizes are needed to detect moderate differences between dye and realized pollen dispersal patterns because the estimation of dispersal parameters suffers low precision.

  11. Occupational Allergy to Peach (Prunus persica Tree Pollen and Potential Cross-Reactivity between Rosaceae Family Pollens

    Directory of Open Access Journals (Sweden)

    Nannan Jiang

    2015-10-01

    Full Text Available Orchard workers in north China are highly exposed to orchard pollens, especially peach and other Rosaceae family pollens during pollination season. The aim of this study was to investigate whether occupational allergy to peach tree pollen as a member of Rosaceae family is IgE-mediated and to evaluate the cross-reactivity among Rosaceae family pollens. Allergen skin test and conjunctival challenge test were performed; enzyme linked immune-sorbent assay (ELISA, inhibiting ELISA, western immunoblotting and inhibiting western immunoblotting were done with Rosaceae family orchard pollens, including peach, apricot, cherry, apple and pear tree pollens. Mass spectrometry was also performed to probe the main allergen component and cross-reactive protein. Sensitizations to peach pollen were found in both skin test and conjunctival challenge in the patients. Serum specific IgE to three pollens (peach, apricot and cherry were detected through ELISA. When peach pollen used as solid phase, ELISA inhibition revealed other four kinds of pollens capable of inducing partial to strong inhibitions (45% to 87%, with the strongest inhibition belonging to apricot pollen (87%. Western   blotting showed predominant IgE binding to a 20 KD protein among these pollens, which appeared to be a cross-reactive allergen component through western blotting inhibition. It was recognized as a protein homologous to glutathione s-transferase 16 from Arabidopsis thaliana. Peach and other Rosaceae family tree pollen may serve as a potential cause of IgE mediated occupational respiratory disease in orchard workers in north China. 

  12. Viability of pollen grains of tetraploid banana

    Directory of Open Access Journals (Sweden)

    Taliane Leila Soares

    2016-01-01

    Full Text Available ABSTRACT Obtaining banana tetraploid cultivars from triploid strains results in total or partial reestablishment of fertility, allowing the occurrence of some fruits with seeds, a feature that is undesirable from a marketing perspective. The objective of this study was to assess the viability of pollen of 12 banana tetraploid hybrids (AAAB by means of in vitro germination and two histochemical tests (acetocarmine and 2,3,5-triphenyltetrazolium chloride. The pollen tube growth was evaluated by germinating grains in three culture media — M1: 0.03% Ca(NO3∙4H2O, 0.02% Mg(SO4∙7H2O, 0.01% KNO3, 0.01% H3BO3 and 15% sucrose; M2: 0.03% Ca(NO3∙4H2O, 0.01% KNO3, 0.01% H3BO3 and 10% sucrose; and M3: 0.015% H3BO3, 0.045% Ca3(PO42 and 25% sucrose. The acetocarmine staining indicated high viability (above 80%, except for the genotypes YB42-17 and Caprichosa, which were 76 and 70%, respectively. However, the in vitro germination rate was lower than 50% for all the genotypes, except for the hybrids YB42-17 (M1 and YB42-47 (M1. The medium M1 provided the greatest germination percentage and pollen tube growth. Among the genotypes assessed, YB42-47 presented the highest germination rate (61.5% and tube length (5.0 mm. On the other hand, the Vitória cultivar had the lowest germination percentage (8.2% in medium M1. Studies of meiosis can shed more light on the differences observed in the evaluated tetraploids, since meiotic irregularities can affect pollen viability.

  13. Variation patterns of pollen production in palm flowers

    DEFF Research Database (Denmark)

    Alapetite, Elodie; Barfod, Anders; Albert, Beatrice

    2016-01-01

    in polyandrous species ranges from 8-9 to several hundreds. It is often heard that the more stamens are produced, the more pollen is produced, particularly in the case of the so-called “pollen flowers”, i.e. flowers in which pollen is the main food resource for floral visitors. However, the correlation between...... pollen production and stamen number has never been so far investigated. The diversity in stamen number observed among palms species and genera provides an ideal case study to test for such a correlation, taking into account phylogenetic constraints. Based on a survey of flowers from 82 species...... representative of the various palm tribes and compared it to stamen number, we show that pollen production in palms ranges from hundreds to millions grains. There is a relationship between stamen number and pollen production in our sampling, particularly in Coryphoideae and Arecoideae where there is a tendency...

  14. Pollen DNA barcoding: current applications and future prospects.

    Science.gov (United States)

    Bell, Karen L; de Vere, Natasha; Keller, Alexander; Richardson, Rodney T; Gous, Annemarie; Burgess, Kevin S; Brosi, Berry J

    2016-09-01

    Identification of the species origin of pollen has many applications, including assessment of plant-pollinator networks, reconstruction of ancient plant communities, product authentication, allergen monitoring, and forensics. Such applications, however, have previously been limited by microscopy-based identification of pollen, which is slow, has low taxonomic resolution, and has few expert practitioners. One alternative is pollen DNA barcoding, which could overcome these issues. Recent studies demonstrate that both chloroplast and nuclear barcoding markers can be amplified from pollen. These recent validations of pollen metabarcoding indicate that now is the time for researchers in various fields to consider applying these methods to their research programs. In this paper, we review the nascent field of pollen DNA barcoding and discuss potential new applications of this technology, highlighting existing limitations and future research developments that will improve its utility in a wide range of applications.

  15. Pollen-related allergy in Italy.

    Science.gov (United States)

    D'Amato, G; Dal Bo, S; Bonini, S

    1992-05-01

    Pollen-related allergies are very common in Italy and pollinosis is the commonest allergic disease. The type of allergenic plants and the prevalence of hay fever varies among regions. In the Mediterranean area there are characteristic climatic conditions (mildness of winter, summer dryness) that facilitate the growth of a typical vegetation with its associated various types of allergenic pollen grains, some of them very different from those of central and northern Europe. Italy has a central position in the Mediterranean basin, but because of its geographic characteristics, there are different climatic aspects with different vegetation between northern, central, and southern areas. Gramineae are the most common allergenic plants in northern and central Italy, where more than 60% of patients with pollinosis are grass-pollen sensitive. Parietaria is the most important pollinating plant in southern Italy and Liguria. Olea europaea, the olive tree with cultivation widespread in the whole Mediterranean basin, is responsible for frequently severe pollinosis, particularly in some regions of the southern Italy.

  16. Impedance Flow Cytometry: A Novel Technique in Pollen Analysis

    OpenAIRE

    Heidmann, Iris; Schade-Kampmann, Grit; Lambalk, Joep; Ottiger, Marcel; Di Berardino, Marco

    2016-01-01

    Introduction An efficient and reliable method to estimate plant cell viability, especially of pollen, is important for plant breeding research and plant production processes. Pollen quality is determined by classical methods, like staining techniques or in vitro pollen germination, each having disadvantages with respect to reliability, analysis speed, and species dependency. Analysing single cells based on their dielectric properties by impedance flow cytometry (IFC) has developed into a comm...

  17. Morphology and viability of castor bean genotypes pollen grains

    OpenAIRE

    Maria Selma Alves Silva Diamantino; Maria Angélica Pereira de Carvalho Costa; Taliane Leila Soares; Daniel Vieira Morais; Simone Alves Silva; Everton Hilo Souza

    2016-01-01

    The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L.) and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitro germinat...

  18. Morphology and viability of castor bean genotypes pollen grains

    OpenAIRE

    Diamantino,Maria Selma Alves Silva; Costa,Maria Angélica Pereira de Carvalho; Soares,Taliane Leila; Morais,Daniel Vieira; Silva,Simone Alves; Souza,Everton Hilo de

    2016-01-01

    ABSTRACT. The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L.) and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitr...

  19. A statistical mixture model for estimating the proportion of unreduced pollen grains in perennial ryegrass (Lolium perenne L.) via the size of pollen grains

    NARCIS (Netherlands)

    Jansen, R.C.; Nijs, A.P.M. den

    1993-01-01

    The size of pollen grains is commonly used to indicate the ploidy level of pollen grains. In this paper observations of the diameter of pollen grains are evaluated from one diploid accession of perennial ryegrass (Lolium perenne L.), which was expected to produce diploid (unreduced) pollen grains in

  20. A DNA barcoding approach to characterize pollen collected by honeybees.

    Directory of Open Access Journals (Sweden)

    Andrea Galimberti

    Full Text Available In the present study, we investigated DNA barcoding effectiveness to characterize honeybee pollen pellets, a food supplement largely used for human nutrition due to its therapeutic properties. We collected pollen pellets using modified beehives placed in three zones within an alpine protected area (Grigna Settentrionale Regional Park, Italy. A DNA barcoding reference database, including rbcL and trnH-psbA sequences from 693 plant species (104 sequenced in this study was assembled. The database was used to identify pollen collected from the hives. Fifty-two plant species were identified at the molecular level. Results suggested rbcL alone could not distinguish among congeneric plants; however, psbA-trnH identified most of the pollen samples at the species level. Substantial variability in pollen composition was observed between the highest elevation locality (Alpe Moconodeno, characterized by arid grasslands and a rocky substrate, and the other two sites (Cornisella and Ortanella at lower altitudes. Pollen from Ortanella and Cornisella showed the presence of typical deciduous forest species; however in samples collected at Ortanella, pollen of the invasive Lonicera japonica, and the ornamental Pelargonium x hortorum were observed. Our results indicated pollen composition was largely influenced by floristic local biodiversity, plant phenology, and the presence of alien flowering species. Therefore, pollen molecular characterization based on DNA barcoding might serve useful to beekeepers in obtaining honeybee products with specific nutritional or therapeutic characteristics desired by food market demands.

  1. A DNA barcoding approach to characterize pollen collected by honeybees.

    Science.gov (United States)

    Galimberti, Andrea; De Mattia, Fabrizio; Bruni, Ilaria; Scaccabarozzi, Daniela; Sandionigi, Anna; Barbuto, Michela; Casiraghi, Maurizio; Labra, Massimo

    2014-01-01

    In the present study, we investigated DNA barcoding effectiveness to characterize honeybee pollen pellets, a food supplement largely used for human nutrition due to its therapeutic properties. We collected pollen pellets using modified beehives placed in three zones within an alpine protected area (Grigna Settentrionale Regional Park, Italy). A DNA barcoding reference database, including rbcL and trnH-psbA sequences from 693 plant species (104 sequenced in this study) was assembled. The database was used to identify pollen collected from the hives. Fifty-two plant species were identified at the molecular level. Results suggested rbcL alone could not distinguish among congeneric plants; however, psbA-trnH identified most of the pollen samples at the species level. Substantial variability in pollen composition was observed between the highest elevation locality (Alpe Moconodeno), characterized by arid grasslands and a rocky substrate, and the other two sites (Cornisella and Ortanella) at lower altitudes. Pollen from Ortanella and Cornisella showed the presence of typical deciduous forest species; however in samples collected at Ortanella, pollen of the invasive Lonicera japonica, and the ornamental Pelargonium x hortorum were observed. Our results indicated pollen composition was largely influenced by floristic local biodiversity, plant phenology, and the presence of alien flowering species. Therefore, pollen molecular characterization based on DNA barcoding might serve useful to beekeepers in obtaining honeybee products with specific nutritional or therapeutic characteristics desired by food market demands.

  2. Inflated Sporopollenin Exine Capsules Obtained from Thin-Walled Pollen

    Science.gov (United States)

    Park, Jae Hyeon; Seo, Jeongeun; Jackman, Joshua A.; Cho, Nam-Joon

    2016-06-01

    Sporopollenin is a physically robust and chemically resilient biopolymer that comprises the outermost layer of pollen walls and is the first line of defense against harsh environmental conditions. The unique physicochemical properties of sporopollenin increasingly motivate the extraction of sporopollenin exine capsules (SECs) from pollen walls as a renewable source of organic microcapsules for encapsulation applications. Despite the wide range of different pollen species with varying sizes and wall thicknesses, faithful extraction of pollen-mimetic SECs has been limited to thick-walled pollen capsules with rigid mechanical properties. There is an unmet need to develop methods for producing SECs from thin-walled pollen capsules which constitute a large fraction of all pollen species and have attractive materials properties such as greater aerosol dispersion. Herein, we report the first successful extraction of inflated SEC microcapsules from a thin-walled pollen species (Zea mays), thereby overcoming traditional challenges with mechanical stability and loss of microstructure. Morphological and compositional characterization of the SECs obtained by the newly developed extraction protocol confirms successful protein removal along with preservation of nanoscale architectural features. Looking forward, there is excellent potential to apply similar strategies across a wide range of unexplored thin-walled pollen species.

  3. Intra-inflorescence pollen viability in accessions of Brachiaria ruziziensis

    Directory of Open Access Journals (Sweden)

    Cristina Maria Pinto de Paula

    2014-05-01

    Full Text Available Knowledge about the pollen viability is important to ensure success in controlled hybridizations and, consequently, support breeding programs. The aims of this study were to evaluate the pollen viability in progenies of artificially induced tetraploid accessions of Brachiaria ruziziensis, and to verify if the position of the flower buds on the raceme affects the pollen viability rate. Staining of aborted and non-aborted pollen (Alexander’s technique was used to determine the viability of the pollen grains. Tetraploid accessions of B. ruziziensis plants had high pollen viability (x = 76.8% to x = 99.6%. Some of these plants had viability rates similar to diploid B. ruziziensis, showing that the induction of chromosome duplication by colchicine did not result in abnormalities in production and morphology of pollen grains. Pollen grains from middle and apical regions of the raceme presented higher viability rates (x = 97.9% and x = 97.7% respectively. The viability of pollen grains in artificially induced tetraploid accessions of B. ruziziensis plants was high, which may favor obtaining fertile descendants in possible crosses

  4. Fraxinus pollen as a source of environmental pollution

    Directory of Open Access Journals (Sweden)

    María Fernández-González

    2016-06-01

    Full Text Available In Southern Europe there are but a few studies focused on the allergenic impact of ash (Fraxinus pollen as a result of its scarce distribution. In the city of Ourense this type of pollen represents 2% of the total atmospheric pollen recorded. The goal of this study is to determine the atmospheric concentrations of Fraxinus pollen and its allergen in Ourense’s atmosphere in 2015, and to assess their relationship with the main meteorological variables. The aim is to assess whether the pollen counts match the actual exposure conditions for allergen-sensitive patients. A Lanzoni VPPS-2000 volumetric sampler was used for pollen sampling, whereas a Burkard Cyclone sampler was used for allergen detection.The flowering period of Fraxinus was long, having a duration of 76 days between the third week of January and the rst week of April as consequence of the asynchronous flowering of the different species growing in the study area. The presence of the ash allergen in the atmosphere can be detected using the main olive tree allergen, Ole e 1. Our study indicates that the combination of pollen counts and allergen quanti cation should be contemplated to estimate the real exposure of sensitive people. In the case of Fraxinus pollen, there may be allergy risk periods before and after the occurrence of the highest pollen concentrations in the atmosphere as a result of special rain and humidity conditions during its flowering period.

  5. Analysis of Airborne Pollen Fall in Edirne,Turkey

    Institute of Scientific and Technical Information of China (English)

    Adem BICAKCI; Goksel OLGUN; Mehmet AYBEKE; Perihan ERKAN; Hulusi MALYER

    2004-01-01

    In the atmosphere of Edirne 12 691 pollen grains belonging to 42 taxa were identified by using of Durham sampler in 2000 and 2001. A total of 6 189 pollen grains per cm2 were recorded in 2000 and a total of 6 502 pollen grains per cm2 in 2001. Total pollen grains consisted of 71.81% grains from arboreal plants, 25.88% grains from non-arboreal plants and 2.31% unidentified pollen grains. Pollen from the following taxa were also found to be prevalent in the atmosphere of Edirne: Gramineae, Pinus sp., Quercus sp.,Cupressaceae/Taxaceae, Platanus sp., Salix sp., Morus sp., Populus sp., Carpinus sp., Juglans sp.,Chenopodiaceae/Amaranthaceae, Fraxinus sp., Fagus sp., Ulmus sp., Ailanthus sp., Alnus sp., Ostrya sp.,Helianthus sp. The season of maximum pollen fall was from April to June, with a prevalence of arboreal pollen in the first month, and of pollen from non-arboreal plants in the last months of the year.

  6. Forecasting model of Corylus, Alnus, and Betula pollen concentration levels using spatiotemporal correlation properties of pollen count.

    Science.gov (United States)

    Nowosad, Jakub; Stach, Alfred; Kasprzyk, Idalia; Weryszko-Chmielewska, Elżbieta; Piotrowska-Weryszko, Krystyna; Puc, Małgorzata; Grewling, Łukasz; Pędziszewska, Anna; Uruska, Agnieszka; Myszkowska, Dorota; Chłopek, Kazimiera; Majkowska-Wojciechowska, Barbara

    The aim of the study was to create and evaluate models for predicting high levels of daily pollen concentration of Corylus, Alnus, and Betula using a spatiotemporal correlation of pollen count. For each taxon, a high pollen count level was established according to the first allergy symptoms during exposure. The dataset was divided into a training set and a test set, using a stratified random split. For each taxon and city, the model was built using a random forest method. Corylus models performed poorly. However, the study revealed the possibility of predicting with substantial accuracy the occurrence of days with high pollen concentrations of Alnus and Betula using past pollen count data from monitoring sites. These results can be used for building (1) simpler models, which require data only from aerobiological monitoring sites, and (2) combined meteorological and aerobiological models for predicting high levels of pollen concentration.

  7. Effects of nitrogen ion implantation on lily pollen germination and the distribution of the actin cytoskeleton during pollen germination

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The effects of low energy nitrogen ion implantation on lily (Lilium davidii Duch.) pollen germination and the distribution of the actin cytoskeleton during pollen germination have been studied. Preliminary results showed that the ratio of pollen germination increased from (16.0±1.6)% to (27.0±2.1)% when implanted with nitrogen ions by 100 keV and a dose of 1013 ions/cm2. Further experiments were performed by staining the actin filaments in pollen with rhodamine-phalloidin and detected by using laser confocol microscopy. After hydration for 10 h, the actin filaments in ion implanted pollen grains tended to form thick bundles oriented in parallel or ring shape at the germinal furrow, indicating that the effect of nitrogen ion implantation on the germination of pollen might be mediated by reorganization of the actin cytoskeleton.

  8. Pollen grains as allergenic environmental factors – new approach to the forecasting of the pollen concentration during the season

    Directory of Open Access Journals (Sweden)

    Dorota Myszkowska

    2014-11-01

    Full Text Available [b]introduction and objectives[/b]. It is important to monitor the threat of allergenic pollen during the whole season, because of practical application in allergic rhinitis treatment, especially in the specific allergen immunotherapy. The aim of the study was to propose the forecast models predicting the pollen occurrence in the defined pollen concentration categories related to the patient exposure and symptom intensity. [b]material and methods[/b]. The study was performed in Cracow (southern Poland, pollen data were collected using the volumetric method in 1991–2012. For all independent variables (meteorological elements and the daily pollen concentrations the running mean for periods: 2-, 3-, 4-, 5-, 6- and 7 days before the predicted day were calculated. The multinomial logistic regression was used to find the relation between the probability of the pollen concentration occurrence in the selected categories and meteorological elements and pollen concentration in days preceding the predicted daily concentration. The models were constructed for each taxon using data in 1991–2011 (without 1992 and 1996 due to missing data in these years and 1998–2011 pollen seasons. [b]results.[/b] The days classified among the lowest category (0–10 PG/m[sup] 3[/sup] (pollen grains/m 3 of air dominated for all the studied taxa. The percentage of the obtained predictions of the pollen occurrence fluctuated between 35–78% which is a sufficient value of model predictions. Considering the studied taxon, the best model accuracy was obtained for models forecasting Betula pollen concentration (both data series, and Poaceae (both data series. [b]conclusions[/b]. The application of the recommended threshold values during the predictive models construction seems to be really useful to estimate the real threat of allergen exposure. It was indicated that the polynomial logistic regression models could be a practical tool for effective forecasting in biological

  9. Decreased Pollen Viability and Thicken Pollen Intine in Antisense Silenced Brassica campestris Mutant of BcMF19

    Institute of Scientific and Technical Information of China (English)

    LIU Jin-long; GAO Ming-hui; LIU Ying; CAO Jia-shu

    2014-01-01

    Brassica campestris male fertility 19 (BcMF19;GenBank accession number GQ902048.1), a gene that is specially expressed in tapetum cells and microspores during anther development in B. campestris ssp. chinensis, which is learned from the previous in situ hybridization study. In the present study, we constructed antisense-silenced plants of BcMF19 using B. campestris ssp. chinensis to validate this prediction. The morphology of the pistils, long anthers, and short anthers was signiifcantly affected in 35sbcmf19 compared with the control samples. 4´-6-Diamidino-2-phenylindole staining revealed that two generative nuclei and one large vegetative nucleus were not affected in the mutant compared with control. Statistical analysis of Alexander’s staining results showed that 96% of the control pollen grains had vitality, whereas only 86% of the mutant pollen grains did. Under scanning electron microscopy, the mutant demonstrated numerous abnormal pollen grains and resembled dried persimmon. The frequency of normal pollen grains was approximately 18%. Under transmission electron microscopy, the pollen intine during the binucleate and mature pollen stages in 35sbcmf19 exhibited abnormal thickening, especially at the germinal furrows, compared with control. In vitro pollen germination test showed that the tips of the mutant pollen tubes transformed into globular alveoli and stopped growing compared with control. On the other hand, in vivo pollen germination test suggested that BcMF19 affected the pollen tube extension in the pistil. These ifndings indicate that BcMF19 is essential to the pollen development and pollen tube extension of B. campestris ssp. chinensis.

  10. Comparison of throughfall and soil solution chemistry between a high-density Corsican pine stand and a naturally regenerated silver birch stand.

    Science.gov (United States)

    De Schrijver, A; Nachtergale, L; Staelens, J; Luyssaert, S; De Keersmaeker, L

    2004-09-01

    In Flanders, critical loads for acidification and eutrophication are exceeded in the majority of the forest stands, and many previously nitrogen limited forest ecosystems have become nitrogen saturated. The present study investigates whether a naturally regenerated stand of silver birch (Betula pendula Roth) contributes less to the acidification and eutrophication of the forest soil than a high-density plantation of Corsican pine (Pinus nigra ssp. laricio Maire). Throughfall deposition of inorganic nitrogen was about 3.5 times higher in the Corsican pine stand than in the birch stand. Potassium throughfall deposition was significantly higher under birch due to higher canopy leaching. Magnesium throughfall deposition was significantly higher under the pine canopy due to higher dry deposition. The lower nitrogen throughfall deposition in the birch stand was reflected in a 60% lower nitrate percolation at 1m depth compared with pine. Nitrate soil percolation is linked to losses of aluminium and base cations.

  11. PollenCALC: Software for estimation of pollen compatibility of self-incompatible allo- and autotetraploid species

    DEFF Research Database (Denmark)

    Aguirre, Andrea A; Wollenweber, Bernd; Frei, Ursula K;

    2012-01-01

    available for predicting pollen haplotype frequencies and pollen compatibility in tetraploid species. Results PollenCALC is a software tool written in C++ programming language that can predict pollen compatibility percentages for polyploid species with a two-locus (S, Z) self-incompatibility system...... provided by this calculator can be used to predict compatibility of pair-crosses in plant breeding applications, to analyze segregation distortion for S and Z genes, as well as linked markers in mapping populations, hypothesis testing of the number of S and Z alleles in a pair cross, and the underlying...

  12. Pollen dispersal in a mountainous area based on pollen analysis of four natural trap types from Lugu Lake, southwest China

    Institute of Scientific and Technical Information of China (English)

    Su-Ping LI; Ya-Qin HU; David Kay FERGUSON; Jian-Xin YAO; Cheng-Sen LI

    2013-01-01

    Palynological analysis of 24 samples from four types of natural pollen traps (Lugu Lake bottom sediments,surface soil,bark samples,and moss cushions) in four sites at different altitudes from the Lugu Lake area,southwest China,has been undertaken to investigate pollen dispersal and deposition in a mountainous area and assist with the interpretation of fossil pollen analysis.Detailed comparisons between the palynological assemblage and the modern vegetation in the Lugu Lake region have been carried out.Preliminary interpretations of the correlation between pollen assemblage and vegetation at the different vertical vegetational zones can be recognized by the percentages of the main taxa,and most of the pollen taxa except Pinus are expected to be underrepresented.Exotic pollen grains can be transported over mountains more than 70 km away by wind.Upslope or downslope transport of pollen grains is crucial when reconstructing palaeoclimate in mountainous areas.We summarize the altitudinal distributions of modern woody plants whose pollen grains are present at three sites,and reveal that pollen grains are more readily carried uphill than downhill.These findings have important implications regarding the reconstruction of vegetation in mountainous regions and the interpretion of palaeoelevations.

  13. Molecular characterisation of birch bark tar by headspace solid-phase microextraction gas chromatography-mass spectrometry: a new way for identifying archaeological glues.

    Science.gov (United States)

    Regert, M; Alexandre, V; Thomas, N; Lattuati-Derieux, A

    2006-01-06

    To develop an analytical methodology, as non-destructive as possible, suitable for the identification of natural substances from archaeological origin, we studied the potentiality of solid-phase microextraction (SPME) for analysing birch bark tar, an adhesive commonly used during ancient times. First of all, birch bark tars were produced by a controlled heating of birch bark. The two kinds of samples obtained using different processes of fabrication, one at liquid state, the second one at solid state, were then analysed by headspace HS-SPME-GC-MS. Different conditions of sample treatment were tested (two different fibre coatings, various times and temperatures of extraction) in order to suggest optimal conditions for the analysis of birch bark tar. Both samples were shown to be rich in volatile organic components. Two main groups of constituents, namely phenolic compounds issued from lignin or tannin known to be present in bark and sesquiterpenoid hydrocarbons, secondary metabolites largely distributed in the plant kingdom, were detected for the first time in birch bark tar. HS-SPME-GC-MS appears thus to be a very efficient method for investigating the volatiles emitted by plant tars and could be further used for the study of birch bark tar samples issued from archaeological context.

  14. Interference of the Histone Deacetylase Inhibits Pollen Germination and Pollen Tube Growth in Picea wilsonii Mast.

    Directory of Open Access Journals (Sweden)

    Yaning Cui

    Full Text Available Histone deacetylase (HDAC is a crucial component in the regulation of gene expression in various cellular processes in animal and plant cells. HDAC has been reported to play a role in embryogenesis. However, the effect of HDAC on androgamete development remains unclear, especially in gymnosperms. In this study, we used the HDAC inhibitors trichostatin A (TSA and sodium butyrate (NaB to examine the role of HDAC in Picea wilsonii pollen germination and pollen tube elongation. Measurements of the tip-focused Ca2+ gradient revealed that TSA and NaB influenced this gradient. Immunofluorescence showed that actin filaments were disrupted into disorganized fragments. As a result, the vesicle trafficking was disturbed, as determined by FM4-64 labeling. Moreover, the distribution of pectins and callose in cell walls was significantly altered in response to TSA and NaB. Our results suggest that HDAC affects pollen germination and polarized pollen tube growth in Picea wilsonii by affecting the intracellular Ca2+ concentration gradient, actin organization patterns, vesicle trafficking, as well as the deposition and configuration of cell wall components.

  15. Biomass and nutrient cycle in fertilized and unfertilized pine, mixed birch and pine and spruce stands on a drained mire.

    OpenAIRE

    Finér, Leena

    1989-01-01

    Biomass, biomass increment and nutrient cycling were studied in (1) a Scots pine (Pinus sylvestris) stand, (2) a Norway spruce (Picea abies) stand and (3) a mixed birch (Betula pubescens)/pine stand on a drained mire at Ilomantsi, eastern Finland in 1979-85. In addition, the effect of NPK and micronutrient fertilizer treatment was studied. Above-ground and root measurements were taken. These data formed the basis of stand biomass and nutrient cycle simulations of fertilized and unfertilized s...

  16. Dissolved organic carbon and nitrogen leaching from Scots pine, Norway spruce and silver birch stands in southern Sweden

    OpenAIRE

    Fröberg, Mats; Hansson, Karna; Kleja, Dan Berggren; Alavi, Ghasem

    2011-01-01

    The effects of three common tree species – Scots pine, Norway spruce and silver birch – on leaching of dissolved organic carbon and dissolved nitrogen were studied in an experimental forest with podzolised soils in southern Sweden. We analyzed soil water collected with lysimeters and modeled water fluxes to estimate dissolved C and N fluxes. Specific UV absorbance (SUVA) was analyzed to get information about the quality of dissolved organic matter leached from the different stands. Under the ...

  17. Features of secondary birch young stands in low mountain Pokuttya (Ukrainian Carpathian mts.

    Directory of Open Access Journals (Sweden)

    S. Y. Milevskaya

    2015-06-01

    Full Text Available Forest landscapes of the region during the last 3–5 centuries undergone the profound anthropogenic transformation. Secondary young stands occupy 25% of the total forest area. The problem of derivatives is particularly relevant for the modern forest typology in the Carpathian region. It requires the reflection in its dynamic trends shaping the stands, especially mixed young stands. The aim of our study consisted in getting the knowledge of the structural features of the secondary phytocoenosis of birch young stands in this area.The object of the study was age class I saplings growing in the mountainous part of Pokuttya, particularly in the basin of the Lutshka River. The conceptual basis of our study is the modern dynamic vision that every forest type is a consecutive series of forest plant communities within each type of homogeneous growing conditions. We apply methods of ecological-floristic research of the Brown-Blanke school in the interpretation of the Polish school phytosociology. However we also take into account both syntaxonomy generalizations of the Ukrainian scientists. The actual material comprises the original geobotanical studies with fixation of the vast majority of species in plant communities. Mainly the species having diagnostic value to separate syntaxons were taken into account in the analytical processing. Young forest stands (with the height of 8–12 m and crown cover of 70% together form the trees Betula pendula and B. pubescens. Fairly numerous admixture is formed by trees Alnus incana; besides, there are Fagus sylvatica, Populus tremula, Quercus robur, Padus avium. For dominants, they can be called “grey-alder birch blackberry sedge bracken fern” – Betula pendula+Alnus incana–Rubus caesius–Carex brizoides+Pteridium aquilinum. It is rich in floristic composition of the plant communities. They contain at least 12 species of trees, 3 species of shrubs, 4 species of bushes and 89 species of herbs. Diagnostic

  18. Effects of long-term elevated ultraviolet-B radiation on phytochemicals in the bark of silver birch (Betula pendula)

    Energy Technology Data Exchange (ETDEWEB)

    Tegelberg, R.; Julkunen-Tiitto, R. [Joensuu Univ., Dept. of Biology, Joensuu (Finland); Aphalo, P. J. [Joensuu Univ., Faculty of Forestry, Joensuu (Finland)

    2002-12-01

    The effects of long-term ultraviolet-B radiation on the concentrations of secondary metabolites such as phenolics and terpenoids in the bark of silver birch saplings were studied. The effects of ultraviolet-B on the concentrations of the main soluble sugars such as sucrose, raffinose, and glucose in silver birch stem were also investigated, given that they are involved in the transpiration and allocation of assimilated carbon, and UV-B-induced changes may affect tree growth. Concentrations of sucrose, raffinose and glucose in bark were found to be higher in UV-treated saplings than in saplings grown in ambient radiation, indicating that stem carbohydrate metabolism was changed by long-term exposure to elevated UV radiation. Saplings in elevated UV-A + UV-B radiation treatment and UV-A radiation control treatment had shown significantly increased concentrations of certain UV-absorbing phenolics compared with saplings in ambient radiation. No effect of radiation treatment was observed on non-UV-B-absorbing terpenoids. These observations led to the conclusion that plant parts accumulate specific phenolic UV-filters in response to UV radiation exposure. The accumulation of sugars in the stems of silver birch saplings in response to UV radiation is believed to affect tree growth, possibly because of a reduction of alpha-cellulose content and consequent reduction in cell wall production. 36 refs., 1 tab., 2 figs.

  19. Impact of ectohumus application in birch and pine nurseries on the presence of soil mites (Acari, Oribatida in particular

    Directory of Open Access Journals (Sweden)

    Klimek Andrzej

    2016-03-01

    Full Text Available Intensively used forest nurseries are characterised by degradation processes that lead to a drop in the quality of seedlings. The main reason of this problem is a decrease in biological soil diversity. Therefore, an attempt of nursery soil enrichment by introducing ectohumus – as compost and fresh litter – from the pine forest was carried out. The research was carried out in 2009–2011 in the Bielawy forest nursery near the city of Toruń, Poland. The objective of the study was to determine the impact of organic fertilisation (compost made up of forest humus and mulching using fresh ectohumus on the density and community composition of Acari mites and on species composition of oribatid mites (Oribatida in the nurseries of silver birch and Scots pine. Mites, especially oribatid mites, were treated as bioindicators of soil biological activity. Research has shown that mulching using fresh ectohumus caused a multiple increase in the density of mites, especially in saprophagous mites Oribatida. Oribatid mites were clearly more numerous in birch cultivation than in that of pine. Overall, 27 species of oribatid mites were found. Mulching resulted in a significant growth in species diversity in both cultivations. The most numerous oribatid mite in the area under the study was Oribatula tibialis. This species was present in all plots and showed clear preference for birch cultivation. Tectocepheus velatus and Oppiella nova, common and known to be present in a variety of environments, were slightly less numerous.

  20. Optimization of ultrasonic-assisted extraction (UAE) of betulin from white birch bark using response surface methodology.

    Science.gov (United States)

    Chen, Qi-he; Fu, Ming-liang; Liu, Jin; Zhang, Hai-feng; He, Guo-qing; Ruan, Hui

    2009-06-01

    Betulin is an abundant naturally occurring triterpene, which makes it a potentially important raw material for a precursor of biologically active compounds. The objective of the current study was to determine the optimum UAE conditions for betulin from B. papyfera bark. The optimum conditions were evaluated with fractional factorial design and optimized using response surface methodology. High yields of betulin were observed from white birch bark by UAE technology. The solvent concentration and the ratio of material to solvent were the most significant parameters on betulin extraction as evaluated through FFD. The extraction conditions were further investigated with central composite design. The fitted second-order model revealed that the optimal conditions consisted of 98% ethonal concentration, 1:42 the ratio of white birch bark to solvent, extraction temperature 50 degrees C, ultrasonic frequency 5kHz and extraction time 3h. Under the optimized condition, the maximum productivity of betulin predicted is 23.17%. The extraction productivity and purity of betulin under the optimized extraction conditions were great higher than that of the non-optimized condition. The present study demonstrates that ultrasound is a great efficiency tool for the fast extraction of betulin from white birch bark.

  1. LATERAL ORGAN BOUNDARIES DOMAIN (LBD)10 interacts with SIDECAR POLLEN/LBD27 to control pollen development in Arabidopsis.

    Science.gov (United States)

    Kim, Min-Jung; Kim, Mirim; Lee, Mi Rha; Park, Soon Ki; Kim, Jungmook

    2015-03-01

    During male gametophyte development in Arabidopsis thaliana, the microspores undergo an asymmetric division to produce a vegetative cell and a generative cell, which undergoes a second division to give rise to two sperm cells. SIDECAR POLLEN/LATERAL ORGAN BOUNDARIES DOMAIN (LBD) 27 plays a key role in the asymmetric division of microspores. Here we provide molecular genetic evidence that a combinatorial role of LBD10 with LBD27 is crucial for male gametophyte development in Arabidopsis. Expression analysis, genetic transmission and pollen viability assays, and pollen development analysis demonstrated that LBD10 plays a role in the male gametophyte function primarily at germ cell mitosis. In the mature pollen of lbd10 and lbd10 expressing a dominant negative version of LBD10, LBD10:SRDX, aberrant microspores such as bicellular and smaller tricellular pollen appeared at a ratio of 10-15% with a correspondingly decreased ratio of normal tricellular pollen, whereas in lbd27 mutants, 70% of the pollen was aborted. All pollen in the lbd10 lbd27 double mutants was aborted and severely shrivelled compared with that of the single mutants, indicating that LBD10 and LBD27 are essential for pollen development. Gene expression and subcellular localization analyses of LBD10:GFP and LBD27:RFP during pollen development indicated that posttranscriptional and/or posttranslational controls are involved in differential accumulation and subcellular localization of LBD10 and LBD27 during pollen development, which may contribute in part to combinatorial and distinct roles of LBD10 with LBD27 in microspore development. In addition, we showed that LBD10 and LBD27 interact to form a heterodimer for nuclear localization.

  2. Correlation between pollen morphology and pollination mechanisms in the Hydrocharitaceae.

    Science.gov (United States)

    Tanaka, Norio; Uehara, Koichi; Murata, Jin

    2004-08-01

    The pollen morphology of 11 genera and 11 species of the Hydrocharitaceae and one species of the Najadaceae was studied using scanning and transmission electron microscopies, and the exine structures and sculptures are discussed in relation to pollination mechanisms and the molecular phylogeny. The pollen grains of the Hydrocharitaceae are spherical, inaperturate, and form monads or tetrads, while those of the Najadaceae are elliptical, inaperturate, and form monads. The entomophilous genera Egeria, Blyxa, Ottelia, Stratiotes, and Hydrocharis share pollen grains that have projections like spines or bacula. The anemophilous genus Limnobium has reticulate pollen grains. The hypohydrophilous genera Thalassia and Najas are characterized by pollen grains with reduced exine structures. The pollen-epihydrophilous genera Elodea and Hydrilla have tightly arranged small spinous pollen grains, and the male flower-epihydrophilous genera Enhalus and Vallisneria have reduced reticulate or gemmate exines. Character state reconstruction of the exine structures and sculptures using a molecular phylogenetic tree suggests that variation in the exine is generally correlated with the pollination mechanism; the selective pressures acting on the pollination mechanisms have reduced the exine structure in hypohydrophilous plants and resulted in various exine sculptures that are adapted to the different pollination mechanisms in entomophilous, anemophilous, and pollen-epihydrophilous plants.

  3. Borassodendron (Palmae) in the Southeast Asian fossil pollen record

    NARCIS (Netherlands)

    Maloney, B.K.

    2000-01-01

    Borassodendron machadonis pollen occurred throughout the Holocene pollen record of Nong Thale Song Hong, Thailand, until about 4000 BP. It was also present in one sample from Khok Phanom Di, Thailand, and in the Mahakam Delta, Kalimantan, records, but B. machadonis has not been reported from the mod

  4. Signalling and the cytoskeleton of pollen tubes of Papaver rhoeas

    NARCIS (Netherlands)

    Snowman, B.N.; Geitmann, A.; Clarke, S.R.; Staiger, C.J.; Franklin, F.C.H.; Emons, A.M.C.; Franklin-Tong, V.E.

    2000-01-01

    Self-incompatibility (SI) is a genetically controlled system used by many flowering plants to prevent self-pollination, often by the inhibition of pollen tube growth. The importance of cytosolic free calcium, [Ca2+]i, for the regulation of pollen tube growth is well known. We have established, using

  5. Pollen morphology of the Euphorbiaceae with special reference to taxonomy

    NARCIS (Netherlands)

    Punt, W.

    1962-01-01

    In the present study pollen morphology of the Euphorbeaceae is treated as an additional character in taxonomy. Besides the greater part of the genera occurring in the system of PAX and K. HOFFMANN (1931), most of the genera published after 1931 are studied. The pollen grains have been described with

  6. Bioclimatic indices as a tool in pollen forecasting.

    Science.gov (United States)

    Valencia-Barrera, Rosa María; Comtois, Paul; Fernández-González, Delia

    2002-09-01

    The use of bioclimatic indices could be a major step forward in the methodology of pollen forecasting. The basis for this proposal is that simple meteorological parameters do not reflect the global status of the atmosphere, but merely some static measurements. However, pollen dispersal is, above all, a dynamic phenomenon, and this fact should be reflected in the variables we used to explain it. Here, we test the two methodologies for routine pollen forecasting by comparing correlation coefficients using the same daily Poaceae airborne pollen data base from León (6 years, from 1994 to 1999) as the dependent variable and either simple daily meteorological variables or compound daily bioclimatic indices as independent variables. Both simple and compound indices reproduced the same profile of evolution of plant eco-physiological requirements, as the length of the study period during the pollen season increased. However, for time frames larger than the main pollen period, bioclimatic indices gave superior coefficients, which seems to indicate that these could be more valuable for pre-season pollen forecasting. The continentality index produced the highest mean coefficient, higher than those generated by any meteorological variable. Furthermore, at least for a Mediterranean climate, site location and evapotranspiration in relation to precipitation seem to be the most promising factors for increasing success when forecasting Poaceae airborne pollen concentration.

  7. Roles of Pectin Methylesterases in Pollen-Tube Growth

    Institute of Scientific and Technical Information of China (English)

    Li-Qun Chen; De Ye

    2007-01-01

    Elongation of the pollen tube in pistil is essential for delivering sperms into the female gametophyte in sexual plant reproduction. Recently, a group of cell wall enzymes, pectin methylesterases (PMEs), have been identified as playing an important role in this process. This article reviews the new understanding of the roles of PMEs in regulating pollen tube growth.

  8. Airborne pollen grains in Bursa, Turkey, 1999-2000,.

    Science.gov (United States)

    Bicakci, Adem; Tatlidil, Sevcan; Sapan, Nihat; Malyer, Hulusi; Canitez, Yakup

    2003-01-01

    In this study, pollen grains were sampled by using a Lanzoni trap (Lanzoni VPPS 2000) in atmosphere of Bursa in 1999 and 2000. During two years. a total of 13,991 pollen grains/m3 which belonged to 59 taxa and unidentified pollen grains were recorded. A total of 7.768 pollen grains were identified in 1999 and a total of 6.223 in 2000. From these taxa, 36 belong to arboreal and 23 taxa to non-arboreal plants. Total pollen grains consist of 78.61% arboreal. 20.37% non-arboreal plants and 1.03% unidentified pollen grains. In the region investigated, Pinus sp., Olea sp., Platanus sp., Gramineae, Cupressaceae/Taxaceae, Quercus sp., Acer sp.. Morus sp. Xanthium sp., Castanea sp., Chenopodiaceae/Amaranthaceae, Corvlus sp., Artemisia sp., Urtica sp.and Fraxinus sp. were responsible for the greatest amounts of pollen. During the study period the pollen concentration reached its highest level in April.

  9. Airborne pollen in European and Asian parts of Istanbul.

    Science.gov (United States)

    Celenk, Sevcan; Bicakci, Adem; Tamay, Zeynep; Guler, Nermin; Altunoglu, M Kemal; Canitez, Yakup; Malyer, Hulusi; Sapan, Nihat; Ones, Ulker

    2010-05-01

    Pollen concentrations in the atmosphere of Istanbul, a city located between two continents, has been monitored for 1 year as part of a larger research program. The sampling sites were located in two different continents: the Asian part (AS) and the European part (EP). The sampling was performed in AS and EP of the city by using Hirst type volumetric method, and pollen grains of 58 and 62 taxa were identified in the two parts, respectively. The pollen spectrum reflected the floristic diversity of the region. The main pollen producers at the sites were characterized by some allergenic pollen and were identified as Cupressaceae/Taxaceae, Urticaceae, Pistacia sp., Quercus sp., Platanus sp., Fraxinus sp., and Xanthium sp. These pollen types contributed to the total pollen sum with a percentage of more than 80% at both monitoring sites. The highest amount of pollen grains was recorded in April. The greatest number of species was recorded in May, when 42 types (AS) and 44 types (EP) were present.

  10. Regulation of pollen tube polarity: Feedback loops rule

    Science.gov (United States)

    Targeted delivery of immotile sperm through growing pollen tubes is a crucial step in achieving sexual reproduction in angiosperms. Unlike diffuse-growing cells, the growth of a pollen tube is restricted to the very apical region where targeted exocytosis and regulated endocytosis occur. The plant-s...

  11. A Method of Recording and Predicting the Pollen Count.

    Science.gov (United States)

    Buck, M.

    1985-01-01

    A hair dryer, plastic funnel, and microscope slide can be used for predicting pollen counts on a day-to-day basis. Materials, methods for assembly, collection technique, meteorological influences, and daily patterns are discussed. Data collected using the apparatus suggest that airborne grass products other than pollen also affect hay fever…

  12. Biological and therapeutic properties of bee pollen: a review.

    Science.gov (United States)

    Denisow, Bożena; Denisow-Pietrzyk, Marta

    2016-10-01

    Natural products, including bee products, are particularly appreciated by consumers and are used for therapeutic purposes as alternative drugs. However, it is not known whether treatments with bee products are safe and how to minimise the health risks of such products. Among others, bee pollen is a natural honeybee product promoted as a valuable source of nourishing substances and energy. The health-enhancing value of bee pollen is expected due to the wide range of secondary plant metabolites (tocopherol, niacin, thiamine, biotin and folic acid, polyphenols, carotenoid pigments, phytosterols), besides enzymes and co-enzymes, contained in bee pollen. The promising reports on the antioxidant, anti-inflammatory, anticariogenic antibacterial, antifungicidal, hepatoprotective, anti-atherosclerotic, immune enhancing potential require long-term and large cohort clinical studies. The main difficulty in the application of bee pollen in modern phytomedicine is related to the wide species-specific variation in its composition. Therefore, the variations may differently contribute to bee-pollen properties and biological activity and thus in therapeutic effects. In principle, we can unequivocally recommend bee pollen as a valuable dietary supplement. Although the bee-pollen components have potential bioactive and therapeutic properties, extensive research is required before bee pollen can be used in therapy. © 2016 Society of Chemical Industry.

  13. The importance of pollen counts in the air: an example

    Directory of Open Access Journals (Sweden)

    Francisco José González Minero

    2016-06-01

    Full Text Available The Bay of Cádiz in general and Sanlúcar de Barrameda in particular were pioneering places for aerobiological analysis in Spain. This study presents unpublished pollen data collected with a Hirst spore trap during a year. Results are structured in pollen calendar form which is easy to interpret by health professionals. This article also intends to pay tribute to those medical pioneers who began their studies in Sanlúcar de Barrameda. On this subject, we discuss the data obtained in 1941 and we relate them with data collected in 2009. The Mediterranean climate and the geographical location of Sanlúcar de Barrameda bring about an archetypical pollen calendar of the towns of the Iberian Peninsula’s southern coast. A total of 21 pollen types are quanti ed, Olea europaea L. (25.1%, Quercus (17.5%, Pinaceae (12.3%, Poaceae (10.2% and Cupressaceae (8.1% being the more abundant types . The months of highest pollen concentration are April and May. The maximum daily concentration was reached on May 13 with 825 grains/m3 of Olea europaea L. pollen. Daily concentrations of grass pollen and other herbaceous plants are not exceptionally high, but they do have a continued presence throughout the year, so the risk of pollen allergies cannot be con ned to spring.

  14. Reconstructing Earth's Past Climates: The Hidden Secrets of Pollen

    Science.gov (United States)

    Steele, Adrienne; Warny, Sophie

    2013-01-01

    "Palynology" is the study of fossil pollen and spores, and these tiny grains can provide fundamental information about past climates on Earth. Among their many unique and useful properties, pollen and spores are composed of some of the most chemically resistant organic compounds found in nature. They are also produced in vast quantities…

  15. Variation in pollen competitive ability in diverse maize lines

    Science.gov (United States)

    Although pollen occupies a small fraction of the angiosperm life cycle, it is of interest for both basic and applied scientific reasons. Seed production depends on a functional male gametophyte achieving fertilization following pollination. Pollen also serves as a vector for ge...

  16. Pollen tube germination in maize does not require transcriptomic changes

    Science.gov (United States)

    One objective for our group is to better understand the molecular and genetic basis of pollen and pollen tube function, given its critical role in seed production and its importance as a means of gene flow between plant populations. We compared gene expression levels in seedlings...

  17. Analysis of Airborne Pollen Fall in Edirne, Turkey

    Institute of Scientific and Technical Information of China (English)

    AdemBICAKCI; GokselOLGUN; MehmetAYBEKE; PerihanERKAN; HulusiMALYER

    2004-01-01

    In the atmosphere of Edirne 12 691 pollen grains belonging to 42 taxa were identified by using of Durham sampler in 2000 and 2001. A total of 6 189 pollen grains per cm2 were recorded in 2000 and a total of 6 502 pollen grains per cm2 in 2001. Total pollen grains consisted of 71.81% grains from arboreal plants, 25.88% grains from non-arboreal plants and 2.31% unidentified pollen grains. Pollen from the following taxa were also found to be prevalent in the atmosphere of Edirne: Gramineae, Pinus sp., Quercus sp., Cupressaceae/Taxaceae, Platanus sp., Salix sp., Morus sp., Populus sp., Carpinus sp., Juglans sp., Chenopodiaceae/Amaranthaceae, Fraxinus sp., Fagus sp., Ulmus sp., Ailanthus sp., Alnus sp., Ostrya sp., Helianthus sp. The season of maximum pollen fall was from April to June, with a prevalence of arboreal pollen in the first month, and of oollen from non-arboreal olants in the last months of the vear.

  18. Sporophytic control of pollen tube growth and guidance in maize.

    Science.gov (United States)

    Lausser, Andreas; Kliwer, Irina; Srilunchang, Kanok-orn; Dresselhaus, Thomas

    2010-03-01

    Pollen tube germination, growth, and guidance (progamic phase) culminating in sperm discharge is a multi-stage process including complex interactions between the male gametophyte as well as sporophytic tissues and the female gametophyte (embryo sac), respectively. Inter- and intra-specific crossing barriers in maize and Tripsacum have been studied and a precise description of progamic pollen tube development in maize is reported here. It was found that pollen germination and initial tube growth are rather unspecific, but an early, first crossing barrier was detected before arrival at the transmitting tract. Pollination of maize silks with Tripsacum pollen and incompatible pollination of Ga1s/Ga1s-maize silks with ga1-maize pollen revealed another two incompatibility barriers, namely transmitting tract mistargeting and insufficient growth support. Attraction and growth support by the transmitting tract seem to play key roles for progamic pollen tube growth. After leaving transmitting tracts, pollen tubes have to navigate across the ovule in the ovular cavity. Pollination of an embryo sac-less maize RNAi-line allowed the role of the female gametophyte for pollen tube guidance to be determined in maize. It was found that female gametophyte controlled guidance is restricted to a small region around the micropyle, approximately 50-100 microm in diameter. This area is comparable to the area of influence of previously described ZmEA1-based short-range female gametophyte signalling. In conclusion, the progamic phase is almost completely under sporophytic control in maize.

  19. Pollen aroma fingerprint of two sunflower (Helianthus annuus L.) genotypes characterized by different pollen colors.

    Science.gov (United States)

    Bertoli, Alessandra; Fambrini, Marco; Doveri, Silvia; Leonardi, Michele; Pugliesi, Claudio; Pistelli, Luisa

    2011-09-01

    Samples of fresh pollen grains, collected from capitula in full bloom from two genotypes of sunflower (Helianthus annuus L.) and characterized by a different color, i.e., white-cream (WC) and orange (O), were analyzed by the HS-SPME (headspacesolid phase microextraction)/GC/MS technique. This study defined for the first time the fingerprint of the sunflower pollen, separated from the disc flowers, to define its contribution to the inflorescence aroma. In the GC/MS fingerprints of the WC and O genotypes, 61 and 62 volatile compounds were identified, respectively. Monoterpene hydrocarbons (34% in O vs. 28% in WC) and sesquiterpene hydrocarbons (37% in O vs. 31% in WC) were ubiquitous in all samples analyzed and represented the main chemical classes. α-Pinene (21% in O vs. 20% in WC) and sabinene (11% in O vs. 6% in WC) were the dominant volatiles, but also a full range of aliphatic hydrocarbons and their oxygenated derivatives gave a decisive contribution to the aroma composition (10% in O vs. 12% in WC). In addition, dendrolasin (3% in O vs. 4% in WC) and some minor constituents such as (E)-hex-2-en-1-ol (0.4% in O vs. 0.1% in WC) were pointed out not only for their contribution to the pollen scent, but also for their well-known role in the plant ecological relationships. Having evaluated two pollen morphs with different carotenoid-based colors, the study sought to highlight also the presence of some volatile precursors or derivatives of these pigments in the aroma. However, the pollen aroma of the two selected genotypes made a specific chemical contribution to the sunflower inflorescence scent without any influence on carotenoid derivatives.

  20. Botany: a record-breaking pollen catapult.

    Science.gov (United States)

    Edwards, Joan; Whitaker, Dwight; Klionsky, Sarah; Laskowski, Marta J

    2005-05-12

    The release of stored elastic energy often drives rapid movements in animal systems, and plant components employing this mechanism should be able to move with similar speed. Here we describe how the flower stamens of the bunchberry dogwood (Cornus canadensis) rely on this principle to catapult pollen into the air as the flower opens explosively. Our high-speed video observations show that the flower opens in less than 0.5 ms--to our knowledge, the fastest movement so far recorded in a plant.

  1. Ambrosia airborne pollen concentration modelling and evaluation over Europe

    Science.gov (United States)

    Hamaoui-Laguel, Lynda; Vautard, Robert; Viovy, Nicolas; Khvorostyanov, Dmitry; Colette, Augustin

    2014-05-01

    Native from North America, Ambrosia artemisiifolia L. (Common Ragweed) is an invasive annual weed introduced in Europe in the mid-nineteenth century. It has a very high spreading potential throughout Europe and releases very allergenic pollen leading to health problems for sensitive persons. Because of its health effects, it is necessary to develop modelling tools to be able to forecast ambrosia air pollen concentration and to inform allergy populations of allergenic threshold exceedance. This study is realised within the framework of the ATOPICA project (https://www.atopica.eu/) which is designed to provide first steps in tools and estimations of the fate of allergies in Europe due to changes in climate, land use and air quality. To calculate and predict airborne concentrations of ambrosia pollen, a chain of models has been built. Models have been developed or adapted for simulating the phenology (PMP phonological modelling platform), inter-annual production (ORCHIDEE vegetation model), release and airborne processes (CHIMERE chemical transport model) of ragweed pollen. Airborne pollens follow processes similar to air quality pollutants in CHIMERE with some adaptations. The detailed methodology, formulations and input data will be presented. A set of simulations has been performed to simulate airborne concentrations of pollens over long time periods on a large European domain. Hindcast simulations (2000 - 2012) driven by ERA-Interim re-analyses are designed to best simulate past periods airborne pollens. The modelled pollen concentrations are calibrated with observations and validated against additional observations. Then, 20-year long historical simulations (1986 - 2005) are carried out using calibrated ambrosia density distribution and climate model-driven weather in order to serve as a control simulation for future scenarios. By comparison with multi-annual observed daily pollen counts we have shown that the model captures well the gross features of the pollen

  2. La longévité du pollen de colza

    OpenAIRE

    Pierre Jacqueline; Renard Michel

    2002-01-01

    Connaître la longévité d’un pollen est une donnée particulièrement intéressante dans le cadre des études de risques de dissémination du pollen. En effet, cela permet de savoir combien de temps une parcelle dont la floraison est terminée reste une source de pollen fécondant. Par ailleurs, une étude de la longévité du pollen pourrait permettre de mieux comprendre les résultats en apparence contradictoires obtenus au cours de diverses expérimentations menées sur la dissémination du pollen de col...

  3. STUDY ON POLLEN VIABILITY AS BIOINDICATOR OF AIR QUALITY

    Directory of Open Access Journals (Sweden)

    Florentina ŞTEFLEA

    2012-01-01

    Full Text Available The aim of this research is to estimate the relationship between pollen viability and atmospheric pollution (in polluted and non-polluted conditions. The study was carried out in the city of Timisoara. Two areas, with different intensity of road traffic (very high and absent but all characterized by the presence of the same plant species, were selected. The pollen of herbaceous spontaneous species, arboreal species and a shrub species was used (Robinia pseudacacia, Aesculus x carnea, Catalpa bignonioides, Albizzia julibrissin, Rosa canina, Sambucus nigra, Malva neglecta, Ranunculus acer, Trifolium repens, Cichorium intybus. The pollen of these species was treated with TTC (2, 3, 5 Tryphenil-Tetrazolium-Chloride staining solution and viability was then estimated by light microscopy. The results of the mean pollen viability percentage of the examined species are reported. Pollen viability of herbaceous plants is significantly different between the two environments.

  4. Pollen morphology of some Geranium subgenus Robertium species of Iran

    Directory of Open Access Journals (Sweden)

    M. Keshavarzi

    2016-06-01

    Full Text Available Geranium (Geraniaceae comprises more than 23 annual or perennial species in Iran. There is no study in Iran with pollen morphology emphasize. The main aim of this study is to find diagnostic pollen characters in studied species. Totally 40 accessions of five species (G. albanum, G. molle, G. purpureum, G. mascatense and G. pusillum were collected. Pollen grains were studied by use of light and Scanning electron microscopy. To reveal the species relationships different multivariate statistical methods were used. The pollen grains were monad, isopolar, radially symmetric and of spheroid, prolate-spheroid or oblate-spheroid classes. The main ornamentation type was clavate, however reticulate but striate was also observed. All sections are clearly separated by their pollen features except of Batrachioidea which show confusion with Ruberta. Species relationship is discussed.

  5. Pollen Morphology of Acinos Miller Species Growing in Turkey

    Institute of Scientific and Technical Information of China (English)

    Ayla Kaya; Hatice Kutluk

    2007-01-01

    The pollen morphology of six taxa of the genus Acinos Miller has been examined under scanning electron microscopy(SEM) and a description of each taxon has been given. Acinos pollen is stephanocolpate (hexacolpate). Two main exine sculpturing types, foveolate-reticulate (only in subspecies of A. troodi) and reticulate have been defined. The dimension for the polar length ranges between 25.8-47.4 μm, equatorial width 24.5-34.4 μm, colpus length 20.0-40.5 μm and colpus width 1.2-2.5 μm. The shape is mostly subprolate to prolate, seldomly prolate-spheroidal. The results reveal rather uniform morphological features, however fine details are characteristic to differentiate the pollen taxa. Acinos pollen also share some common morphological features with the other Lamiaceae pollen.

  6. Cytology of 2n Pollen Formation in Nonastringent Persimmon

    Institute of Scientific and Technical Information of China (English)

    TANG Xian-ying; LUO Zheng-rong

    2002-01-01

    Cytological mechanisms of 2n pollen formation in ‘Zenjimaru' nonastringent persimmon (Diospyros kaki L.f. ) were studied. The following abnormalities in meiosis were found to be responsible for the production of 2n pollens: (1) disoriented spindles, including parallel, fused and tripolar spindles, were formed at metaphase Ⅱ and anaphase Ⅱ; (2) the nuclei at telophase Ⅱ were arranged to two poles, each of which contained two nuclei, or to three poles, one of which contained two nuclei, the other two contained one nucleus respectively; (3) dyads and triads were produced at the tetrad stage. The dyad would develop into two 2n pollens, and the triad would develop into one 2n and two n pollens. The 2n pollens produced by this mechanism were genetically equivalent to FDR (first division restitution) gametes, thus providing a potential value for sexual polyploidization.

  7. POLLEN MORPHOLOGY OF CROCUS L.(IRIDACEAE IN BULGARIA

    Directory of Open Access Journals (Sweden)

    UZUNDZHALIEVA KATYA SPASOVA

    2012-06-01

    Full Text Available The pollen of the wild species from the genus Crocus L., spread in Bulgaria has been analyzed. The investigations, made by light microscope show that the pollen of these species is spherical in shape and round in outlines, comparatively big. These morphological characteristics of the pollen of the wild Bulgarian Crocuses define it as a primitive one [6]. The Scanning Electron Microscope investigations, made by Beug [1], established two types of pollen morphology. The results of our investigation led to the conclusion that the same types are also presented in Bulgarian species: – C.biflorus –type, or syncolpate and C.vernus – type, or inaperturate. Eight of the species belong to the first type and only C. pallasii belongs to the second. The pollen of C. reticulatus is with quite unclear aperture – maybe transition to the inaperturate type.

  8. Pollen irradiation and possible gene transfer in Nicotiana species

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1985-01-01

    Progeny from crosses of Nicotiana langsdorffii with gamma irradiated pollen of Nicotiana alata ‘Crimson Bedder’ showed skewed segregation in the F2 favoring the maternal parent. This is probably not gene transfer in a strict sense, rather just an extreme case of reduced transmission of irradiated...... chromosomes, leading to massive overrepresentation of maternal genes. Gene transfer or mutational loss may explain some anomalous F1 plants. Segregation in the F2 progeny showed the presence of several genes from the irradiated pollen. Crosses of Nicotiana sylvestris, N. plumbaginifolia N. paniculata......, and Petunia parodii with irradiated pollen from N. alata and Petunia hybrida showed no evidence of gene transfer, nor did experiments with irradiated mentor pollen. This indicates that gene transfer with irradiated pollen between non-crossing species or between species giving sterile hybrids is probably...

  9. ASSESSING HUMAN EXPOSURE TO GRASS POLLEN IN DENMARK

    DEFF Research Database (Denmark)

    Peel, Robert George; Hertel, Ole; Herbert, Rob

    Objectives: Exposure to pollen is typically assessed using data collected at fixed roof-top monitoring stations, which give a general picture of airborne pollen concentrations over a wide region. Actual exposure levels can be obtained through personal exposure monitoring. This is typically done...... using a suction sampler worn on the chest or lapel that measures breathing zone concentration; a more useful exposure parameter for pollen allergy sufferers is the amount of pollen inhaled, i.e. the dose. The objective of this study was to investigate how well monitoring station data reflect actual...... exposure, something that is currently not well understood. Methods: Exposure samples were collected during the 2011 grass pollen season in an area of abundant unmaintained grass coverage close to the centre of Aarhus, Denmark. Sampling was performed at two-hourly intervals between 12:00 and 20:00 on 14...

  10. Modern pollen rain in the Lake Qinghai basin, China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Lake Qinghai is the largest inland brackish lake in China and lies within the NE Tibetan Plateau. Our study shows that pollen assemblages in each vegetation belt are significantly correlated with the vegetation types of this area. Among the herbaceous and shrubby pollen assemblages, Artemisia is over-represented, while Poaceae, Cyperaceae and Polygonaceae are under-represented. Artemisia/ Chenopodiaceae (A/C) ratios with the regional vegetation characteristic can be used as a proper index to reconstruct the history of vegetation and climate in Lake Qinghai basin. Modern pollen in the lake mainly comes from the nearby vegetation, controlled by the directions and velocity of the wind. The distribution of modern pollen in Lake Qinghai tends to be similar in most part of the lake. The difference of pollen sedimentation process in the lake can be potentially influenced by the focusing function of the lake, river streams, and lake current.

  11. Airborne castanea pollen forecasting model for ecological and allergological implementation.

    Science.gov (United States)

    Astray, G; Fernández-González, M; Rodríguez-Rajo, F J; López, D; Mejuto, J C

    2016-04-01

    Castanea sativa Miller belongs to the natural vegetation of many European deciduous forests prompting impacts in the forestry, ecology, allergological and chestnut food industry fields. The study of the Castanea flowering represents an important tool for evaluating the ecological conservation of North-Western Spain woodland and the possible changes in the chestnut distribution due to recent climatic change. The Castanea pollen production and dispersal capacity may cause hypersensitivity reactions in the sensitive human population due to the relationship between patients with chestnut pollen allergy and a potential cross reactivity risk with other pollens or plant foods. In addition to Castanea pollen's importance as a pollinosis agent, its study is also essential in North-Western Spain due to the economic impact of the industry around the chestnut tree cultivation and its beekeeping interest. The aim of this research is to develop an Artificial Neural Networks for predict the Castanea pollen concentration in the atmosphere of the North-West Spain area by means a 20years data set. It was detected an increasing trend of the total annual Castanea pollen concentrations in the atmosphere during the study period. The Artificial Neural Networks (ANNs) implemented in this study show a great ability to predict Castanea pollen concentration one, two and three days ahead. The model to predict the Castanea pollen concentration one day ahead shows a high linear correlation coefficient of 0.784 (individual ANN) and 0.738 (multiple ANN). The results obtained improved those obtained by the classical methodology used to predict the airborne pollen concentrations such as time series analysis or other models based on the correlation of pollen levels with meteorological variables.

  12. Image analysis in automatic system of pollen recognition

    Directory of Open Access Journals (Sweden)

    Piotr Rapiejko

    2012-12-01

    Full Text Available In allergology practice and research, it would be convenient to receive pollen identification and monitoring results in much shorter time than it comes from human identification. Image based analysis is one of the approaches to an automated identification scheme for pollen grain and pattern recognition on such images is widely used as a powerful tool. The goal of such attempt is to provide accurate, fast recognition and classification and counting of pollen grains by computer system for monitoring. The isolated pollen grain are objects extracted from microscopic image by CCD camera and PC computer under proper conditions for further analysis. The algorithms are based on the knowledge from feature vector analysis of estimated parameters calculated from grain characteristics, including morphological features, surface features and other applicable estimated characteristics. Segmentation algorithms specially tailored to pollen object characteristics provide exact descriptions of pollen characteristics (border and internal features already used by human expert. The specific characteristics and its measures are statistically estimated for each object. Some low level statistics for estimated local and global measures of the features establish the feature space. Some special care should be paid on choosing these feature and on constructing the feature space to optimize the number of subspaces for higher recognition rates in low-level classification for type differentiation of pollen grains.The results of estimated parameters of feature vector in low dimension space for some typical pollen types are presented, as well as some effective and fast recognition results of performed experiments for different pollens. The findings show the ewidence of using proper chosen estimators of central and invariant moments (M21, NM2, NM3, NM8 NM9, of tailored characteristics for good enough classification measures (efficiency > 95%, even for low dimensional classifiers

  13. Hydration, sporoderm breaking and germination of Cupressus arizonica pollen.

    Science.gov (United States)

    Chichiriccò, G; Spanò, L; Torraca, G; Tartarini, A

    2009-05-01

    In vitro and in vivo rehydration and germination in Cupressus arizonica pollen were examined using light and scanning electron microscopy. Shed pollen has 12.6% water content, which reduced to 8.2% after dispersal, and this latter pollen survived for some months at room temperature and for years at -10 degrees C. Rehydration requires breaking of the sporoderm walls and depends on the composition and pH of the rehydration medium. Acidity restrains the breakage, while alkalinity promotes it. Pollen division follows exine shedding and requires the persistence of the mucilaginous layer; hence, pH values countering these outcomes prevent division. Division results in a large and a small cell separated by a callosic wall. A pollen tube develops from the innermost intine of the large cell, which is callosic, and extends into the mucilaginous middle intine. The percentage germination never exceeded 17% in all tested media. In vivo, pollen rehydrates and casts off the exine in the micropylar drop. Drop withdrawal brings pollen to the apical nucellar cells that degenerate in the meantime, and it leaves a deposit on the surface of the micropylar canal. After contaction of the nucellar cells, the pollen flattens and its mucilaginous layer shrinks and disappears. This occurs simultaneously with sealing of the micropylar canal. During this time, pollen divides asymmetrically without the callosic wall, and the larger cell develops a tube in the interface with the nucellus. Only some pollen grains accomplish adhesion to the nucellus and germinate. The in vitro and in vivo developmental stages are discussed.

  14. Molecular basis of pollen-related food allergy: identification of a second cross-reactive IgE epitope on Pru av 1, the major cherry (Prunus avium) allergen.

    Science.gov (United States)

    Wiche, Regina; Gubesch, Michaela; König, Herbert; Fötisch, Kay; Hoffmann, Andreas; Wangorsch, Andrea; Scheurer, Stephan; Vieths, Stefan

    2005-01-01

    Birch (Betula verrucosa) pollen-associated food allergy is a well-characterized syndrome, which is due to the cross-reactivity of IgE antibodies to homologous allergens in various foods. One crossreacting area on the major birch pollen allergen Bet v 1 and its homologue in cherry (Prunus avium) Pru av 1 has already been identified. This is the so-called 'P-loop' region, which encompasses amino acid residues around position 45 and is found on the two virtually identical tertiary protein structures. We tried to determine an additional IgE cross-reacting patch on Pru av 1 and Bet v 1. The putative IgE-binding region on Pru av 1 was localized with a mAb (monoclonal antibody) that was generated against Bet v 1, and cross-reacts with several Bet v 1 homologues in food and inhibits the binding of patients' IgE to Pru av 1. mAb reactivity pattern was analysed and amino acid positions 28 and 108 of Pru av 1 were selected and mutated by site-directed mutagenesis. The Pru av 1 mutants were produced as recombinant proteins and characterized for their folding, mAb- and IgE-binding capacity and allergenic potency with a cellular assay using the humanized rat basophilic leukaemia cell line RBL-25/30. Amino acid position 28 is involved in a second major IgE-binding region on Pru av 1 and probably on Bet v 1. The identification of this second major IgE-binding region is an essential prerequisite to understand the phenomenon of cross-reactivity and its clinical consequences, and to produce hypoallergenic proteins for an improved immunotherapy of type I allergy.

  15. Detection of Malware and Malicious Executables Using E-Birch Algorithm

    Directory of Open Access Journals (Sweden)

    Dr. Ashit Kumar Dutta

    2016-01-01

    Full Text Available Malware detection is one of the challenges to the modern computing world. Web mining is the subset of data mining used to provide solutions for complex problems. Web intelligence is the new hope for the field of computer science to bring solution for the malware detection. Web mining is the method of web intelligence to make web as an intelligent tool to combat malware and phishing websites. Generally, malware injected through websites into the user system and modifies the executable file and paralyze the whole activity of the system. Antivirus application utilizes the data mining technique to find the malware in the web. There is a need of heuristic approach to solve the malware problem. Dynamic analysis methods yield better result than the static methods. Data mining is the best option for the dynamic analysis of malware or malicious program. The purpose of the research is to apply the enhanced Birch algorithm to find the malware and modified executables of Windows and Android operating system.

  16. Analysis of Individual Tree Competition Effect on Diameter Growth of Silver Birch in Estonia

    Directory of Open Access Journals (Sweden)

    Kobra Maleki

    2015-08-01

    Full Text Available Aim of study: The present study evaluates a set of competition indices including spatially explicit indices combined with different competitor selection approaches and non-spatially explicit competition indices. The aim was to quantify and describe the neighbouring effects on the tree diameter growth of silver birch trees. Area of study: Region throughout Estonia. Material and methods: Data from the Estonian Network of Forest Research Plots was used. After quantifying the selected indices, the best non-spatial indices and spatial indices (combined with neighbour selection methods were separately devised into a growth model as a predictor variable to assess the ability of the diameter growth model before and after adding competition measures. To test the species-specific effect on the competition level, the superior indices were recalculated using Ellenberg’s light indicators and incorporated into the diameter growth model. Main results: Statistical analyses showed that the diameter growth is a function of neighbourhood interactions and spatial indices were better growth predictors than non-spatial indices. In addition, the best selections of competitive neighbours were acquired based on the influence zone and the competition elimination angle concepts, and using Ellenberg’s light values had no significant improvement in quantifying the competition effects. Research highlights: Although the best ranking spatial competition measures were superior to the best non-spatial indices, the differences were negligible.

  17. Artificially decreased vapour pressure deficit in field conditions modifies foliar metabolite profiles in birch and aspen.

    Science.gov (United States)

    Lihavainen, Jenna; Keinänen, Markku; Keski-Saari, Sarita; Kontunen-Soppela, Sari; Sõber, Anu; Oksanen, Elina

    2016-07-01

    Relative air humidity (RH) is expected to increase in northern Europe due to climate change. Increasing RH reduces the difference of water vapour pressure deficit (VPD) between the leaf and the atmosphere, and affects the gas exchange of plants. Little is known about the effects of decreased VPD on plant metabolism, especially under field conditions. This study was conducted to determine the effects of artificially decreased VPD on silver birch (Betula pendula Roth.) and hybrid aspen (Populus tremula L.×P. tremuloides Michx.) foliar metabolite and nutrient profiles in a unique free air humidity manipulation (FAHM) field experiment during the fourth season of humidity manipulation, in 2011. Long-term exposure to decreased VPD modified nutrient homeostasis in tree leaves, as demonstrated by a lower N concentration and N:P ratio in aspen leaves, and higher Na concentration and lower K:Na ratio in the leaves of both species in decreased VPD than in ambient VPD. Decreased VPD caused a shift in foliar metabolite profiles of both species, affecting primary and secondary metabolites. Metabolic adjustment to decreased VPD included elevated levels of starch and heptulose sugars, sorbitol, hemiterpenoid and phenolic glycosides, and α-tocopherol. High levels of carbon reserves, phenolic compounds, and antioxidants under decreased VPD may modify plant resistance to environmental stresses emerging under changing climate.

  18. Methane consumption and soil respiration by a birch forest soil in West Siberia

    Science.gov (United States)

    Nakano, Tomoko; Inoue, Gen; Fukuda, Masami

    2004-07-01

    Methane and carbon dioxide fluxes were measured in a birch forest soil in West Siberia, in August 1999, June 2000 and September 2000. The study site had a very thick organic horizon that was subject to drought during the observation periods. The soils always took up CH4, while CO2 was released from the surface to the atmosphere. CH4 consumption and CO2 emission rates ranged from 0.092 to 0.28 mg C m2 h1 and from 110 to 400 mg C m2 h1 respectively. The CH4 consumption rate and soil temperatures showed significant relationships for individual measurements. The soil respiration rate was weakly correlated with individual soil temperatures. This study examined the effect of current and lagged soil temperatures at a depth of 5 cm on CH4 consumption and soil respiration. The variation in the correlation coefficient between CH4 consumption and lagged soil temperature was greatest at a 4-h lag, whereas that for soil respiration showed a gentle peak at lags from several hours to half a day. This difference in the temperature-related lag effect between CH4 consumption and soil respiration results from differences in the exchange processes. Neither flux showed any correlation with soil moisture. The limited variation in soil moisture during our observation period may account for the lack of correlation. However, the droughty soil conditions resulted in high gas diffusion and, consequently, high CH4 consumption.

  19. Quantification of C uptake in subarctic birch forest after setback by an extreme insect outbreak

    Science.gov (United States)

    Heliasz, Michal; Johansson, Torbjörn; Lindroth, Anders; Mölder, Meelis; Mastepanov, Mikhail; Friborg, Thomas; Callaghan, Terry V.; Christensen, Torben R.

    2011-01-01

    The carbon dynamics of northern natural ecosystems contribute significantly to the global carbon balance. Periodic disturbances to these dynamics include insect herbivory. Larvae of autumn and winter moths (Epirrita autumnata and Operophtera brumata) defoliate mountain birch (Betula pubescens) forests in northern Scandinavia cyclically every 9-10 years and occasionally (50-150 years) extreme population densities can threaten ecosystem stability. Here we report impacts on C balance following a 2004 outbreak where a widespread area of Lake Torneträsk catchment was severely defoliated. We show that in the growing season of 2004 the forest was a much smaller net sink of C than in a reference year, most likely due to lower gross photosynthesis. Ecosystem respiration in 2004 was smaller and less sensitive to air temperature at nighttime relative to 2006. The difference in growing season uptake between an insect affected and non-affected year over the 316 km2 area is in the order of 29 × 103 tonnes C equal to a reduction of the sink strength by 89%.

  20. Antimicrobial effect of bee collected pollen extract to Enterobacteriaceae genera after application of bee collected pollen in their feeding

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2013-10-01

    Full Text Available In this study we researched antimicrobial activity of bee pollen extracts to Enterobacteriaceae genera isolated from chicken intestinal tract after application of bee collected pollen in their feeding. We used well plate agar diffusion method for antimicrobial testing of bee pollen extract and disc diffusion method for antibiotic susceptibility testing of bacteria by EUCAST. Identification of bacteria was done by test kit Enterotest 24. We identified tree bacterial strains: E. coli, P. mirabilis and K. oxytoca. We determined that K. oxytoca was resistant to ampicillin only and others identified strain were sensitive to used antibiotics. Also we determined antimicrobial effect of bee pollen extract to all tested strains of Enterobacteriaceae genera which were isolated from intestinal tract of chicken after application of bee collected pollen extract in their feeding. From obtained results we could be conclude that bacteria isolated from chicken after application of bee pollen extract had more resistance to bee collected pollen extract in in vitro experiment as E. coli CCM 3988, which did not be in contact with bee pollen extract.

  1. Immunochemical Characterization of Acacia Pollen Allergens and Evaluation of Cross-Reactivity Pattern with the Common Allergenic Pollens

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    Mohammad-Hosein Shamsbiranvand

    2014-01-01

    Full Text Available Pollen from the Acacia has been reported as an important source of pollinosis in tropical and subtropical regions of the world. The aim of this study was to characterize the IgE binding protein of Acacia farnesiana pollen extract and evaluate cross-reactivity with the most allergenic pollens. In this study, pollen extract was fractionated by SDS-PAGE and the allergenic profile was determined by IgE-immunoblotting and specific ELISA using forty-two Acacia allergic patients. Potential cross-reactivity among Acacia and selected allergenic plants was evaluated with ELISA and immunoblotting inhibition experiments. There were several resolved protein fractions on SDS-PAGE which ranged from 12 to 85 kDa. Several allergenic protein bands with molecular weights approximately between 12 and 85 kDa were recognized by IgE-specific antibodies from Acacia allergic patients in the immunoblot assay. The inhibition by the Prosopis juliflora pollen extract was more than those by other pollen extracts. Moreover, the wheal diameters generated by the Acacia pollen extract were highly correlated with those of P. juliflora pollen extracts. The findings suggest that several proteins such as 15, 23, 45, and 50 kDa proteins could be used as diagnostic and therapeutic reagents for patients allergic to A. farnesiana and P. juliflora.

  2. Expression of an Exo-β-glucanase Gene Is Specifically Related to Lily Pollen Germination and Pollen Tube Growth

    Institute of Scientific and Technical Information of China (English)

    LIU Xizhen; HUANG Jian; GAO Rongfu; LI Yiqin

    2005-01-01

    The present study is expected to provide better understanding of how exo-β-glucanase acts on the biochemo-rheological property of the cell wall, and thus the regulation mechanism of pollen tube growth. A polymerase chain reaction (PCR)-based strategy and cDNA library screening were used to clone an exo-β-glucanase gene (LP-ExoI) from Lilium longiflorum pollen tubes. The LP-ExoI sequence showed a high level of homology to that of reported plant exo-β-glucan hydrolases. Phylogenetic analysis demonstrated that there was close relationship between LP-ExoI and other exo-glucan hydrolases in Poacea plants. Northern analysis indicated that LP-ExoI transcripts stored in pollen grains at low levels; LP-ExoI transcription level enhanced at 2 h after the onset of pollen incubation and remained relatively high during pollen tube elongation. Moreover, the expression of LP-ExoI was undetectable in petals, filaments, stigmas, styles, ovaries, leaves, and stems. These results suggest that LP-ExoI gene is a late pollen gene, specifically contributing to the regulation of lily pollen germination and pollen tube growth.

  3. Ion Implantation Hampers Pollen Tube Growth and Disrupts Actin Cytoskeleton Organization in Pollen Tubes of Pinus thunbergii

    Institute of Scientific and Technical Information of China (English)

    LI Guoping; HUANG Qunce; YANG Lusheng; QIN Guangyong

    2008-01-01

    Pollen grains of Pinus thunbergii Parl. (Japanese black pine) were implanted with 30 keV nitrogen ion beams and the effects of nitrogen ion implantation on pollen tube growth in vitro and the organization of actin cytoskeleton in the pollen tube cell were investigated using a confocal laser scanning microscope after fluorescence labeling. Treatment with ion implanta-tion significantly blocked pollen tube growth. Confocal microscopy showed that ion implantation disrupted actin filament cytoskeleton organization in the pollen tube. It was found that there was a distinct correlation between the inhibition of pollen tube growth and the disruption of actin cytoskeleton organization, indicating that an intact actin cytoskeleton is essential for con-tinuous pollen tube elongation in Pinus thunbergii. Although the detailed mechanism for the ion-implantation-induced bioeffect still remains to be elucidated, the present study assumes that the cytoskeleton system in pollen grains may provide a key target in response to ion beam im-plantation and is involved in mediating certain subsequent cytological changes.

  4. Overexpression of the tomato pollen receptor kinase LePRK1 rewires pollen tube growth to a blebbling mode

    Science.gov (United States)

    The tubular growth of a pollen tube cell is crucial for the sexual reproduction of flowering plants. LePRK1 is a pollen-specific and plasma membrane–localized receptor-like kinase from tomato (Solanum lycopersicum). LePRK1 interacts with another receptor, LePRK2, and with KINASE PARTNER PROTEIN (KPP...

  5. Does bee pollen cause to eosinophilic gastroenteropathy?

    Science.gov (United States)

    Güç, Belgin Usta; Asilsoy, Suna; Canan, Oğuz; Kayaselçuk, Fazilet

    2015-09-01

    Bee pollen is given to children by mothers in order to strengthen their immune systems. There are no studies related with the side effects of bee polen in the literature. In this article, the literature was reviewed by presenting a case of allergic eosinophilic gastropathy related with bee polen. A 5-year old child was admitted due to abdominal pain. Edema was detected on the eyelids and pretibial region. In laboratory investigations, pathology was not detected in terms of hepatic and renal causes that would explain the protein loss of the patient diagnosed with hypoproteinemia and hypoalbuminemia. Urticaria was detected during the follow-up visit. When the history of the patient was deepened, it was learned that bee pollen was given to the patient every day. The total eosinophil count was found to be 1 800/mm(3). Allergic gastroenteropathy was considered because of hypereosinophilia and severe abdominal pain and endoscopy was performed. Biopsy revealed abundant eosinophils in the whole gastric mucosa. A diagnosis of allergic eosinophilic gastropathy was made. Bee polen was discontinued. Abdominal pain and edema disappeared in five days. Four weeks later, the levels of serum albumin and total eosinophil returned to normal.

  6. Direct contact between dendritic cells and bronchial epithelial cells inhibits T cell recall responses towards mite and pollen allergen extracts in vitro.

    Science.gov (United States)

    Papazian, D; Wagtmann, V R; Hansen, S; Würtzen, P A

    2015-08-01

    Airway epithelial cells (AECs) form a polarized barrier along the respiratory tract. They are the first point of contact with airborne antigens and are able to instruct resident immune cells to mount appropriate immune responses by either soluble or contact-dependent mechanisms. We hypothesize that a healthy, polarized epithelial cell layer inhibits inflammatory responses towards allergens to uphold homeostasis. Using an in-vitro co-culture model of the airway epithelium, where a polarized cell layer of bronchial epithelial cells can interact with dendritic cells (DCs), we have investigated recall T cell responses in allergic patients sensitized to house dust mite, grass and birch pollen. Using allergen extract-loaded DCs to stimulate autologous allergen-specific T cell lines, we show that AEC-imprinted DCs inhibit T cell proliferation significantly of Bet v 1-specific T cell lines as well as decrease interleukin (IL)-5 and IL-13 production, whereas inhibition of Phl p 5-specific T cells varied between different donors. Stimulating autologous CD4(+) T cells from allergic patients with AEC-imprinted DCs also inhibited proliferation significantly and decreased production of both T helper type 1 (Th1) and Th2 cytokines upon rechallenge. The inhibitory effects of AECs' contact with DCs were absent when allergen extract-loaded DCs had been exposed only to AECs supernatants, but present after direct contact with AECs. We conclude that direct contact between DCs and AECs inhibits T cell recall responses towards birch, grass and house dust mite allergens in vitro, suggesting that AECs-DC contact in vivo constitute a key element in mucosal homeostasis in relation to allergic sensitisation.

  7. Mechanical damage to pollen aids nutrient acquisition in Heliconius butterflies (Nymphalidae).

    Science.gov (United States)

    Krenn, Harald W; Eberhard, Monika J B; Eberhard, Stefan H; Hikl, Anna-Laetitia; Huber, Werner; Gilbert, Lawrence E

    2009-12-01

    Neotropical Heliconius and Laparus butterflies actively collect pollen onto the proboscis and extract nutrients from it. This study investigates the impact of the processing behaviour on the condition of the pollen grains. Pollen samples (n = 72) were collected from proboscides of various Heliconius species and Laparus doris in surrounding habitats of the Tropical Research Station La Gamba (Costa Rica). Examination using a light microscope revealed that pollen loads contained 74.88 ± 53.67% of damaged Psychotria pollen, 72.04 ± 23.4% of damaged Psiguria/Gurania pollen, and 21.35 ± 14.5% of damaged Lantana pollen (numbers represent median ± first quartile). Damaged pollen grains showed deformed contours, inhomogeneous and/or leaking contents, or they were empty. Experiments with Heliconius and Laparus doris from a natural population in Costa Rica demonstrated that 200 min of pollen processing behaviour significantly increased the percentage of damaged pollen of Psychotria compared to pollen from anthers (P = 0.015, Z = -2.44, Mann-Whitney U-test). Examination of pollen loads from green house reared Heliconius butterflies resulted in significantly greater amounts of damaged Psiguria pollen after 200 min of processing behaviour compared to pollen from flowers (P < 0.001, Z = -4.583, Mann-Whitney U-test). These results indicate that pollen processing functions as extra oral digestion whereby pollen grains are ruptured to make the content available for ingestion.

  8. Pollen viability and storage temperature for Southern highbush and Rabbiteye blueberry breeding

    Science.gov (United States)

    Pollen viability, as measured by tetrad germination, has been reported, but these studies focused on freshly collected pollen and did not address viability of pollen stored at different temperatures over time. Moreover, genetic differences in pollen viability have been reported in blueberry genotype...

  9. Characterization of the maize pollen transcriptome: Validation of microarray results using quantitative real-time PCR

    Science.gov (United States)

    Pollen is the primary means of gene flow between plants and plant populations and plays a critical role in seed production. Pollen fitness can be defined as the ability of a particular pollen grain to outcompete other pollen present on the stigma and complete fertilization, thus ...

  10. Airborne Pollen Grains of Bozüyük (Bilecik, Turkey)

    Institute of Scientific and Technical Information of China (English)

    Cengiz T(U)RE; Elif SALKURT

    2005-01-01

    Airborne pollen grains in the atmosphere of Bozüyük were investigated over a 2 yr period from 2000 to 2001 using a Durham sampler. A total number of pollen grains of 5 170 pollen grains belonging to 32taxa were identified and recorded along with some unidentified pollen grains. Of all the pollen grains, 78.66%were arboreal, 19.20% were non-arboreal, and 2.12% were unidentified. The majority of pollen grains investigated were Pinus, Platanus, Quercus, Cupressaceae, Poaceae, Fagus, Salix, Rosaceae, Urticaceae,Asteraceae, and Chenopodiaceae. The maximum number of pollen grains was recorded in May.

  11. Microwave-Assisted Drying for the Conservation of Honeybee Pollen

    Directory of Open Access Journals (Sweden)

    Angelo Canale

    2016-05-01

    Full Text Available Bee pollen is becoming an important product thanks to its nutritional properties, including a high content of bioactive compounds such as essential amino acids, antioxidants, and vitamins. Fresh bee pollen has a high water content (15%–30% wt %, thus it is a good substrate for microorganisms. Traditional conservation methods include drying in a hot air chamber and/or freezing. These techniques may significantly affect the pollen organoleptic properties and its content of bioactive compounds. Here, a new conservation method, microwave drying, is introduced and investigated. The method implies irradiating the fresh pollen with microwaves under vacuum, in order to reduce the water content without reaching temperatures capable of thermally deteriorating important bioactive compounds. The method was evaluated by taking into account the nutritional properties after the treatment. The analyzed parameters were phenols, flavonoids, with special reference to rutin content, and amino acids. Results showed that microwave drying offers important advantages for the conservation of bee pollen. Irrespective of microwave power and treatment time, phenol and flavonoid content did not vary over untreated fresh pollen. Similarly, rutin content was unaffected by the microwave drying, suggesting that the microwave-assisted drying could be a powerful technology to preserve bioprotective compounds in fresh pollen.

  12. On the Relationship between Pollen Size and Genome Size

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    Charles A. Knight

    2010-01-01

    Full Text Available Here we test whether genome size is a predictor of pollen size. If it were, inferences of ancient genome size would be possible using the abundant paleo-palynolgical record. We performed regression analyses across 464 species of pollen width and genome size. We found a significant positive trend. However, regression analysis using phylogentically independent contrasts did not support the correlated evolution of these traits. Instead, a large split between angiosperms and gymnosperms for both pollen width and genome size was revealed. Sister taxa were not more likely to show a positive contrast when compared to deeper nodes. However, significantly more congeneric species had a positive trend than expected by chance. These results may reflect the strong selection pressure for pollen to be small. Also, because pollen grains are not metabolically active when measured, their biology is different than other cells which have been shown to be strongly related to genome size, such as guard cells. Our findings contrast with previously published research. It was our hope that pollen size could be used as a proxy for inferring the genome size of ancient species. However, our results suggest pollen is not a good candidate for such endeavors.

  13. Automated pollen identification using microscopic imaging and texture analysis.

    Science.gov (United States)

    Marcos, J Víctor; Nava, Rodrigo; Cristóbal, Gabriel; Redondo, Rafael; Escalante-Ramírez, Boris; Bueno, Gloria; Déniz, Óscar; González-Porto, Amelia; Pardo, Cristina; Chung, François; Rodríguez, Tomás

    2015-01-01

    Pollen identification is required in different scenarios such as prevention of allergic reactions, climate analysis or apiculture. However, it is a time-consuming task since experts are required to recognize each pollen grain through the microscope. In this study, we performed an exhaustive assessment on the utility of texture analysis for automated characterisation of pollen samples. A database composed of 1800 brightfield microscopy images of pollen grains from 15 different taxa was used for this purpose. A pattern recognition-based methodology was adopted to perform pollen classification. Four different methods were evaluated for texture feature extraction from the pollen image: Haralick's gray-level co-occurrence matrices (GLCM), log-Gabor filters (LGF), local binary patterns (LBP) and discrete Tchebichef moments (DTM). Fisher's discriminant analysis and k-nearest neighbour were subsequently applied to perform dimensionality reduction and multivariate classification, respectively. Our results reveal that LGF and DTM, which are based on the spectral properties of the image, outperformed GLCM and LBP in the proposed classification problem. Furthermore, we found that the combination of all the texture features resulted in the highest performance, yielding an accuracy of 95%. Therefore, thorough texture characterisation could be considered in further implementations of automatic pollen recognition systems based on image processing techniques.

  14. Pollen Grain and Hybridization Studies in the Genus Capsicum

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    Tomi Lois OLATUNJI

    2016-03-01

    Full Text Available The current study aimed to evaluate the pollen viability of the commonly cultivated varieties of Capsicum species and assessed the potentials for gene exchange among the genotypes through hybridization studies. Capsicum annuum var. abbreviatum, C. annuum var. acuminatum, C. annuum var. grossum and C. frutescens var. baccatum were the species and varieties used in this study. The present findings indicated that the percentage of pollen viability varied in the studied Capsicum genotypes. The highest pollen viability was obtained in C. annuum var. abbreviatum (96.3%, followed by C. annuum var. grossum (95%, and C. annuum var. acuminatum (91.1%. The lowest pollen viability was recorded in C. frutescens var. baccatum (86.2%. The pollen viability was high in most varieties indicating that meiosis is normal, resulting in viable pollen grains. Several intraspecific and interspecific crosses were performed among the Capsicum genotypes and three putative hybrid fruits were produced. Percentage successes obtained in the crosses were low and comparable in both intra and inter-specific crosses. In the entire crosses pattern, pollination success of 10% was recorded for C. frutescens var. baccatum and C. annuum var. acuminatum. Knowing the nature and viability of pollen grains may help in predicting the success rate of hybridization and the successful crosses between C. frutescens var. baccatum and C. annuum var. acuminatum suggest that these two varieties are the closest genetically.

  15. Pollen Morphology of Parnassia L. (Parnassiaceae) and Its Systematic Implications

    Institute of Scientific and Technical Information of China (English)

    Ding WU; Hong WANG; De-Zhu LI; Stephen BLACKMORE

    2005-01-01

    The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type Ⅰ, with foveolate-reticulate sculpture; (ii) type Ⅱ, with a finely reticulate sculpture; and (iii) type Ⅲ, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect.Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China,with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi,implying that Southwest China is the center of diversification of the genus.

  16. Morphology and viability of castor bean genotypes pollen grains

    Directory of Open Access Journals (Sweden)

    Maria Selma Alves Silva Diamantino

    2016-01-01

    Full Text Available The objective of this work was to characterize the morphology and viability of the pollen of 15 genotypes of castor bean (Ricinus communis L. and to generate information that can assist in the selection of highly promising male parents for future use in genetic improvement programs aimed at producing seeds for oil extraction. Acetolysis and scanning electron microscopy was used to characterize the morphology of the pollen. The viability of the pollen grains was estimated by in vitro germination and colorimetric analysis (acetocarmine 2% and 2, 3, 5-triphenyltetrazolium chloride 1%. For the in vitro germination, pollen grains were grown in 10 types of solidified culture medium consisting of different concentrations of sucrose, boric acid, calcium nitrate, magnesium sulfate and potassium nitrate. The pollen grains had the following characteristics: medium size, isopolar and subspheroidal shape, radial symmetry, circular ambit, 3-colporate, elongated endoapertures, tectate exine and granulated sexine. The acetocarmine dye overestimated pollen viability. The media M5 and M8 were the most efficient at promoting the germination of pollen grains. The studied genotypes had high levels of viability and can therefore be used as male parents in genetic improvement programs.

  17. Patterns and sources of variation in pollen deposition and pollen tube formation in flowers of the endemic monoecious shrub Cnidoscolus souzae (Euphorbiaceae).

    Science.gov (United States)

    Arceo-Gómez, G; Alonso, C; Abdala-Roberts, L; Parra-Tabla, V

    2016-07-01

    Pollen deposition and pollen tube formation are key components of angiosperm reproduction but intraspecific variation in these has rarely been quantified. Documenting and partitioning (populations, plants and flowers) natural variation in these two aspects of plant reproduction can help uncover spatial mosaics of reproductive success and underlying causes. In this study, we assess variation in pollen deposition and pollen tube formation for the endemic monoecious shrub Cnidoscolus souzae throughout its distribution range in Mexico, and determine how this variation is structured among populations, plants and flowers. We also infer the relative importance of pollen quantity and quality in determining pollination success in this species. While we found no evidence suggesting that pollen receipt limits C. souzae reproduction across 19 populations, we did find extensive variation in pollen load size and pollen tube number per flower. Total variation in pollen receipt and pollen tube number was mostly explained by intra-individual and among-population variance. Furthermore, pollen load size had a stronger effect on the number of pollen tubes at the base of the style than pollen germination rate, suggesting that pollen quantity may be more important than quality for pollen tube success in C. souzae. Our results suggest that both small within-plant flower differences and broad-scale differences in community attributes can play an important role in determining pollination success. We emphasise the need to evaluate patterns and sources of variation in pollen deposition and pollen tube formation as a first step in understanding the causes of variation in pollination success over broad spatial scales.

  18. Study on Floral and Pollen Characters of Tetraploid Rice

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-xin; CHEN Jian-guo; CHEN Dong-ling; SONG Zhao-jian; DAI Bing-cheng; CAI De-tian

    2009-01-01

    Polyploidization is the evolution trend of many crops, and the yield increased obviously after polyploidization. The polyploidization of rice often brings "gigas" of both vegetative organs and seeds. Howevere, in rice breeding, it is required for restoring lines to have not only big anthers but also abundant pollens. People often doubt that the enlargement of the floral organ may just be enlargement of cell size in polyploid rice. So, it is of significance to study characteristics of floral organs and pollens of several tetraploid rice varieties or lines. Floral organ and pollen characteristics of Sg99012 and HN2026 were studied comparatively by stages and different ploidy levels, with the materials 9311, HD9802S, and PA64S as the control. The results showed that chromosome doubling had much more influence on floral characteristics of every lines than seeding by stages, and the tetraploids of every lines displayed "gigas". In correlation analysis, spikelet length, spikelet width, and anther length had significant correlation; spikelet width and anther width had significant correlation, too. Both seeding by stages and chromosome doubling made the correlations of characters between every floral organ changed to some extent. Seeding by stages had little effect on pollen diameter and fertility of HN2026-4X and Sg99012-4X. But chromosome doubling increased pollen size of every lines remarkably, and also increased the pollen quantity of PMeS (polyploid meiosis stability) restoring line HN2026-4X and gene map restoring line 9311-4X remarkably, whereas only had little effect on that of sterile lines. Moreover, chromosome doubling changed pollen fertility and made the number of fertility pollen of 9311 reduced significantly, but the pollen fertility of HN2026 (PMeS restoring line) and PA64S (sterile line) almost had no change after chromosome doubling. The results showed that tetraploid restoring lines had advantage of abundant and big size pollens, and tetraploid sterile

  19. Promising method advancement in palynology: a supplement to pollen analysis

    DEFF Research Database (Denmark)

    Enevold, Renée; Odgaard, Bent Vad

    2016-01-01

    The analysis of Non Pollen Palynomorphs (NPPs) has evolved over the last few decades to be a fruitful supplement to palynological surveys and has especially proven to be a useful addition when interpreting anthropogenic disturbance of the natural environment. NPPs in anthropogenic soils and archa......The analysis of Non Pollen Palynomorphs (NPPs) has evolved over the last few decades to be a fruitful supplement to palynological surveys and has especially proven to be a useful addition when interpreting anthropogenic disturbance of the natural environment. NPPs in anthropogenic soils...... from sediment-, pollen- and macrofossil analyses. Fungal ascospore x1000. Photo: Renée Enevold...

  20. Sulfinylated Azadecalins act as functional mimics of a pollen germination stimulant in Arabidopsis pistils

    OpenAIRE

    Qin, Yuan; Wysocki, Ronald J.; Somogyi, Arpad; Feinstein, Yelena; Franco, Jessica Y.; Tsukamoto, Tatsuya; Dunatunga, Damayanthi; Levy, Clara; Smith, Steven; Simpson, Robert; Gang, David; Johnson, Mark A.; Palanivelu, Ravishankar

    2011-01-01

    Polarized cell elongation is triggered by small molecule cues during development of diverse organisms. During plant reproduction, pollen interactions with the stigma result in the polar outgrowth of a pollen tube, which delivers sperm cells to the female gametophyte to effect double fertilization. In many plants, pistils stimulate pollen germination. However, in Arabidopsis, the effect of pistils on pollen germination and the pistil factors that stimulate pollen germination remain poorly char...

  1. Viability and seasonal distribution patterns of Scots pine pollen in Finland.

    Science.gov (United States)

    Pulkkinen, P.; Rantio-Lehtimäki, A.

    1995-01-01

    Germination ability and airborne counts of Scots pine (Pinus sylvestris L.) pollen were studied during the spring of 1993 at Turku in southern Finland (60 degrees 32' N, 22 degrees 28' E) and at Utsjoki in northern Finland (69 degrees 45' N, 27 degrees 01' E). Pollen waas trapped from the beginning of May to the end of June in a high-volume air sampler. Germination tests were performed to determine the in vitro pollen viability of the trapped pollen. Airborne pine pollen counts were obtained from a continuously operating Burkard trap located near each high-volume sampler. When male flowering began, phenological observations were carried out on pollen grains collected in rotored samplers located in pine and spruce stands and open fields near Turku and Utsjoki. In southern Finland, the peak period of pine pollen production was short, lasting for only 3 days, but it accounted for about 80% of the total germinating pine pollen yield for the year. The peak count was on May 20, with over 2000 germinating pollen grains per cubic meter of air. Pollen germination rates of up to 70% were obtained during the week preceding the local pollen peak, and rates reached almost 90% on the peak day. Pollen viability remained at 45 to 65% for 1 week after the peak. There was no significant difference between the pollen counts for day and night, indicating that during the main pollen season, the pollen source was close to Turku. Before the local pollen peak, the counts of living pine pollen were low, indicating that pine pollen transported over long distances was of little ecological importance in 1993 in the Turku area. In northern Finland, the first pollen grains were caught on July 4, and the peak day was July 13. However, no viable pollen was observed during this period, indicating that there was little gene drift from southern to northern Finland in 1993.

  2. BVOC responses to realistic nitrogen fertilization and ozone exposure in silver birch.

    Science.gov (United States)

    Carriero, G; Brunetti, C; Fares, S; Hayes, F; Hoshika, Y; Mills, G; Tattini, M; Paoletti, E

    2016-06-01

    Emission of BVOC (Biogenic Volatile Organic Compounds) from plant leaves in response to ozone exposure (O3) and nitrogen (N) fertilization is poorly understood. For the first time, BVOC emissions were explored in a forest tree species (silver birch, Betula pendula) exposed for two years to realistic levels of O3 (35, 48 and 69 ppb as daylight average) and N (10, 30 and 70 kg ha(-1) yr(-1), applied weekly to the soil as ammonium nitrate). The main BVOCs emitted were: α-pinene, β-pinene, limonene, ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexanal. Ozone exposure increased BVOC emission and reduced total leaf area. The effect on emission was stronger when a short-term O3 metric (concentrations at the time of sampling) rather than a long-term one (AOT40) was used. The effect of O3 on total leaf area was not able to compensate for the stimulation of emission, so that responses to O3 at leaf and whole-plant level were similar. Nitrogen fertilization increased total leaf area, decreased α-pinene and β-pinene emission, and increased ocimene, hexanal and DMNT emission. The increase of leaf area changed the significance of the emission response to N fertilization for most compounds. Nitrogen fertilization mitigated the effects of O3 exposure on total leaf area, while the combined effects of O3 exposure and N fertilization on BVOC emission were additive and not synergistic. In conclusion, O3 exposure and N fertilization have the potential to affect global BVOC via direct effects on plant emission rates and changes in leaf area.

  3. Climate warming feedback from mountain birch forest expansion: reduced albedo dominates carbon uptake.

    Science.gov (United States)

    de Wit, Heleen A; Bryn, Anders; Hofgaard, Annika; Karstensen, Jonas; Kvalevåg, Maria M; Peters, Glen P

    2014-07-01

    Expanding high-elevation and high-latitude forest has contrasting climate feedbacks through carbon sequestration (cooling) and reduced surface reflectance (warming), which are yet poorly quantified. Here, we present an empirically based projection of mountain birch forest expansion in south-central Norway under climate change and absence of land use. Climate effects of carbon sequestration and albedo change are compared using four emission metrics. Forest expansion was modeled for a projected 2.6 °C increase in summer temperature in 2100, with associated reduced snow cover. We find that the current (year 2000) forest line of the region is circa 100 m lower than its climatic potential due to land-use history. In the future scenarios, forest cover increased from 12% to 27% between 2000 and 2100, resulting in a 59% increase in biomass carbon storage and an albedo change from 0.46 to 0.30. Forest expansion in 2100 was behind its climatic potential, forest migration rates being the primary limiting factor. In 2100, the warming caused by lower albedo from expanding forest was 10 to 17 times stronger than the cooling effect from carbon sequestration for all emission metrics considered. Reduced snow cover further exacerbated the net warming feedback. The warming effect is considerably stronger than previously reported for boreal forest cover, because of the typically low biomass density in mountain forests and the large changes in albedo of snow-covered tundra areas. The positive climate feedback of high-latitude and high-elevation expanding forests with seasonal snow cover exceeds those of afforestation at lower elevation, and calls for further attention of both modelers and empiricists. The inclusion and upscaling of these climate feedbacks from mountain forests into global models is warranted to assess the potential global impacts.

  4. The formation of pollen in male flowers and yearly atmospheric pollen counts of Cryptomeria japonica in the following year

    Directory of Open Access Journals (Sweden)

    Hideaki Taira

    1998-01-01

    Full Text Available Prediction of yearly atmospheric pollen counts is a very important component in the prevention of allergenic symptoms. We investigated the relationship between atomspheric pollen counts and the formation of male flowers of Cryptomeriajaponica D. Don (C. japonica. An atmospheric pollen survey of C. japonica was conducted from 1983 to 1996 using a Durham’s sampler. A regression analysis was performed between the total pollen count and July temperature in previous years. The atmospheric pollen counts of C. japonica had a high positive correlation with the mean temperature in July of the previous year. However, the predicted using average mean July temperature records of the previous year were insufficient, especially in years following high pollen count. In experimental conditions, using 60 C. japonica trees in pots, the formation of male flowers was shown to increase with a rise in incubation temperature. In a forest of C. japonica, our results showed that the length and weight of new needle growth from old needles, which produced many flowers in the previous year, were shorter and lighter, respectively. These aerobiological and plant physiological studies provide evidence that a smaller number of pollen counts are a common result in a year following one in which many male flowers are produced, even if the mean July temperature of that year was high.

  5. Automated DNA extraction from pollen in honey.

    Science.gov (United States)

    Guertler, Patrick; Eicheldinger, Adelina; Muschler, Paul; Goerlich, Ottmar; Busch, Ulrich

    2014-04-15

    In recent years, honey has become subject of DNA analysis due to potential risks evoked by microorganisms, allergens or genetically modified organisms. However, so far, only a few DNA extraction procedures are available, mostly time-consuming and laborious. Therefore, we developed an automated DNA extraction method from pollen in honey based on a CTAB buffer-based DNA extraction using the Maxwell 16 instrument and the Maxwell 16 FFS Nucleic Acid Extraction System, Custom-Kit. We altered several components and extraction parameters and compared the optimised method with a manual CTAB buffer-based DNA isolation method. The automated DNA extraction was faster and resulted in higher DNA yield and sufficient DNA purity. Real-time PCR results obtained after automated DNA extraction are comparable to results after manual DNA extraction. No PCR inhibition was observed. The applicability of this method was further successfully confirmed by analysis of different routine honey samples.

  6. Large-Scale Variations in Lumber Value Recovery of Yellow Birch and Sugar Maple in Quebec, Canada.

    Directory of Open Access Journals (Sweden)

    Mariana Hassegawa

    Full Text Available Silvicultural restoration measures have been implemented in the northern hardwoods forests of southern Quebec, Canada, but their financial applicability is often hampered by the depleted state of the resource. To help identify sites most suited for the production of high quality timber, where the potential return on silvicultural investments should be the highest, this study assessed the impact of stand and site characteristics on timber quality in sugar maple (Acer saccharum Marsh. and yellow birch (Betula alleghaniensis Britt.. For this purpose, lumber value recovery (LVR, an estimate of the summed value of boards contained in a unit volume of round wood, was used as an indicator of timber quality. Predictions of LVR were made for yellow birch and sugar maple trees contained in a network of more than 22000 temporary sample plots across the Province. Next, stand-level variables were selected and models to predict LVR were built using the boosted regression trees method. Finally, the occurrence of spatial clusters was verified by a hotspot analysis. Results showed that in both species LVR was positively correlated with the stand age and structural diversity index, and negatively correlated with the number of merchantable stems. Yellow birch had higher LVR in areas with shallower soils, whereas sugar maple had higher LVR in regions with deeper soils. The hotspot analysis indicated that clusters of high and low LVR exist across the province for both species. Although it remains uncertain to what extent the variability of LVR may result from variations in past management practices or in inherent site quality, we argue that efforts to produce high quality timber should be prioritized in sites where LVR is predicted to be the highest.

  7. Elevated air humidity affects hydraulic traits and tree size but not biomass allocation in young silver birches (Betula pendula

    Directory of Open Access Journals (Sweden)

    Arne eSellin

    2015-10-01

    Full Text Available As changes in air temperature, precipitation, and air humidity are expected in the coming decades, studies on the impact of these environmental shifts on plant growth and functioning are of major importance. Greatly understudied aspects of climate change include consequences of increasing air humidity on forest ecosystems, predicted for high latitudes. The main objective of this study was to find a link between hydraulic acclimation and shifts in trees’ resource allocation in silver birch (Betula pendula Roth in response to elevated air relative humidity (RH. A second question was whether the changes in hydraulic architecture depend on tree size. Two years of application of increased RH decreased the biomass accumulation in birch saplings, but the biomass partitioning among aboveground parts (leaves, branches, and stems remained unaffected. Increased stem Huber values (xylem cross-sectional area to leaf area ratio observed in trees under elevated RH did not entail changes in the ratio of non-photosynthetic to photosynthetic tissues. The reduction of stem-wood density is attributable to diminished mechanical load imposed on the stem, since humidified trees had relatively shorter crowns. Growing under higher RH caused hydraulic conductance of the root system (KR to increase, while KR (expressed per unit leaf area decreased and leaf hydraulic conductance increased with tree size. Saplings of silver birch acclimate to increasing air humidity by adjusting plant morphology (live crown length, slenderness, specific leaf area, and fine-root traits and wood density rather than biomass distribution among aboveground organs. The treatment had a significant effect on several hydraulic properties of the trees, while the shifts were largely associated with changes in tree size but not in biomass allocation.

  8. Phylogeny of chitinases and its implications for estimating horizontal gene transfer from chitinase-transgenic silver birch (Betula pendula).

    Science.gov (United States)

    Lohtander, Katileena; Pasonen, Hanna-Leena; Aalto, Markku K; Palva, Tapio; Pappinen, Ari; Rikkinen, Jouko

    2008-01-01

    Chitinases are hydrolytic enzymes that have been employed in biotechnology in attempts to increase plants' resistance against fungal pathogens. Genetically modified plants have given rise to concerns of the spreading of transgenes into the environment through vertical or horizontal gene transfer (HGT). In this study, chitinase-like sequences from silver birch (Betula pendula) EST-libraries were identified and their phylogenetic relationships to other chitinases were studied. Phylogenetic analyses were used to estimate the frequency of historical gene transfer events of chitinase genes between plants and other organisms, and the usefulness of phylogenetic analyses as a source of information for the risk assessment of transgenic silver birch carrying a sugar beet chitinase IV gene was evaluated. Thirteen partial chitinase-like sequences, with an approximate length of 600 bp, were obtained from the EST-libraries. The sequences belonged to five chitinase classes. Some bacterial chitinases from Streptomyces and Burkholderia, as well as a chitinase from an oomycete, Phytophthora infestans, grouped together with the class IV chitinases of plants, supporting the hypothesis that some class IV chitinases in bacteria have evolved from eukaryotic chitinases via horizontal gene transfer. According to our analyses, HGT of a chitinase IV gene from eukaryotes to bacteria has presumably occurred only once. Based on this, the likelihood for the HGT of chitinase IV gene from transgenic birch to other organisms is extremely low. However, as risk is a function of both the likelihood and consequences of an event, the effects of rare HGT event(s) will finally determine the level of the risk.

  9. Investigating Pollen and Gene Flow of WYMV-Resistant Transgenic Wheat N12-1 Using a Dwarf Male-Sterile Line as the Pollen Receptor.

    Directory of Open Access Journals (Sweden)

    Shanshan Dong

    Full Text Available Pollen-mediated gene flow (PMGF is the main mode of transgene flow in flowering plants. The study of pollen and gene flow of transgenic wheat can help to establish the corresponding strategy for preventing transgene escape and contamination between compatible genotypes in wheat. To investigate the pollen dispersal and gene flow frequency in various directions and distances around the pollen source and detect the association between frequency of transgene flow and pollen density from transgenic wheat, a concentric circle design was adopted to conduct a field experiment using transgenic wheat with resistance to wheat yellow mosaic virus (WYMV as the pollen donor and dwarf male-sterile wheat as the pollen receptor. The results showed that the pollen and gene flow of transgenic wheat varied significantly among the different compass sectors. A higher pollen density and gene flow frequency was observed in the downwind SW and W sectors, with average frequencies of transgene flow of 26.37 and 23.69% respectively. The pollen and gene flow of transgenic wheat declined dramatically with increasing distance from its source. Most of the pollen grains concentrated within 5 m and only a few pollen grains were detected beyond 30 m. The percentage of transgene flow was the highest where adjacent to the pollen source, with an average of 48.24% for all eight compass directions at 0 m distance. Transgene flow was reduced to 50% and 95% between 1.61 to 3.15 m, and 10.71 to 20.93 m, respectively. Our results suggest that climate conditions, especially wind direction, may significantly affect pollen dispersal and gene flow of wheat. The isolation-by-distance model is one of the most effective methods for achieving stringent transgene confinement in wheat. The frequency of transgene flow is directly correlated with the relative density of GM pollen grains in air currents, and pollen competition may be a major factor influencing transgene flow.

  10. Isolation of a pollen-specific promoter in tritordeum

    Institute of Scientific and Technical Information of China (English)

    Tu Zhiming; Zhang Jiangzhou; Chen Lin; Chuan Qin; Yang Guangxiao; He Guangyuan

    2011-01-01

    The promoter is a cis-acting element in regulating gene expression. A promoterless plasmid containing UidA gene was transformed into tritordeum by barmbadment. Histochemical analysis of various tissues in transgenic tritordeum was carried to examine tissue-specific expression of GUS(beta-glucuronidase) activity. The pollen-specific promoter was trapped and identified successfully in a transformant line. PCR(polymerase chain reaction) method was used to isolate this pollen-specific promoter. By sequencing and analyzing the amplified fragment from PCR, a part of UidA gene and a flanking sequence were obtained. Some essential elements of plant promoters were found in the sequence. To determine the function of it, the cloned fragment was fused with UidA gene, then cloned and transformed into Triticum durum. The transgenic plant transformed by this vector showed GUS expression only in pollen. Therefore a pollen-specific promoter was isolated successfully.

  11. Pollen genetic markers for detection of mutagens in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Nilan, R.A.; Rosichan, J.L.; Arenaz, P.; Hodgdon, A.L.; Kleinhofs, A.

    1980-01-01

    To utilize and exploit pollen for in situ mutagen monitoring, screening and toxicology, the range of genetic traits in pollen must be identified and analyzed. To be useful for the development of mutagen detection systems proteins should be: (1) activity stainable or immunologically identifiable in the pollen, (2) the products of one to three loci; and (3) gametophytic and nuclear in origin. Several proteins, including alcohol dehydrogenase in maize, which meet these criteria are discussed. The waxy locus in barley and maize which controls starch deposition for pollen screening and mutant detection. Thirty waxy mutant lines, induced by sodium azide and gamma-rays are characterized for spontaneous and induced reversion frequencies, allelism, karyotype, amylose content, and UDPglucose glucosyltransferase (waxy gene product) activity. Twelve mutant alleles are being mapped by recombinant frequencies.

  12. Regulatory networks in pollen development under cold stress

    Directory of Open Access Journals (Sweden)

    Kamal Dev Sharma

    2016-03-01

    Full Text Available Cold stress modifies anthers’ metabolic pathways to induce pollen sterility. Cold-tolerant plants, unlike the susceptible ones, produce high proportion of viable pollen. Anthers in susceptible plants, when exposed to cold stress, increase abscisic acid (ABA metabolism and reduce ABA catabolism. Increased ABA negatively regulates expression of tapetum cell wall bound invertase and monosaccharide transport genes resulting in distorted carbohydrate pool in anther. Cold-stress also reduces endogenous levels of the bioactive gibberellins (GAs, GA4 and GA7, in susceptible anthers by repression of the GA biosynthesis genes. Here we discuss recent findings on mechanisms of cold susceptibility in anthers which determine pollen sterility. We also discuss differences in regulatory pathways between cold-stressed anthers of susceptible and tolerant plants that decide pollen sterility or viability.

  13. Preliminary study on radiocarbon AMS dating of pollen

    Institute of Scientific and Technical Information of China (English)

    周卫建; 周杰; 萧家仪; D.Donahue; A.J.T.Jull

    1999-01-01

    17 samples were collected from aeolian and lacustrine profiles within the environment sensitive zone of the Loess Plateau, and an experimental method was established which is suitable for pollen extraction from aeolian sediment. A comparative study of pollen dating was carried out using the accelerator mass spectrometry (AMS) 14C dating of known age samples, and then an experiment with the pollen concentrates was performed. The results indicate that pollen that has been deposited simultaneously with sediment in a stable environment can provide reliable ages. This technique will provide a way of improving the chronological framework for the Loess Plateau since the late Pleistocene. The 14C dating was combined with field investigations, and from the geological record within this zone, evidence was extracted of four major monsoon precipitation changes during the transition from the late Pleistocene to Holoeene.

  14. Change in Ragweed Pollen Season, 1995-2015

    Data.gov (United States)

    U.S. Environmental Protection Agency — This figure shows how the length of ragweed pollen season changed at 11 locations in the central United States and Canada between 1995 and 2015. Data were provided...

  15. Pollen analyses of Pleistocene hyaena coprolites from Montenegro and Serbia

    Directory of Open Access Journals (Sweden)

    Argant Jacqueline

    2007-01-01

    Full Text Available The results of pollen analyses of hyaena coprolites from the Early Pleistocene cave of Trlica in northern Montenegro and the Late Pleistocene cave of Baranica in southeast Serbia are described. The Early Pleistocene Pachycrocuta brevirostris, and the Late Pleistocene Crocuta spelaea are coprolite-producing species. Although the pollen concentration was rather low, the presented analyses add considerably to the much-needed knowledge of the vegetation of the central Balkans during the Pleistocene. Pollen extracted from a coprolite from the Baranica cave indicates an open landscape with the presence of steppe taxa, which is in accordance with the recorded conditions and faunal remains. Pollen analysis of the Early Pleistocene samples from Trlica indicate fresh and temperate humid climatic conditions, as well as the co-existence of several biotopes which formed a mosaic landscape in the vicinity of the cave.

  16. Do urban canyons influence street level grass pollen concentrations?

    DEFF Research Database (Denmark)

    Peel, Robert George; Kennedy, Roy; Smith, Matt

    2014-01-01

    In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city centre...... street canyon environments in Aarhus, Denmark, and London, UK, during the grass pollen seasons of 2010 and 2011 respectively. For the period mid-day to late evening, street level concentrations in both cities tended to be lower than roof-level concentrations, though this difference was found...... source distribution. In the London study, an increase in relative humidity was linked to a significant decrease in street/roof level concentration ratio, and a possible causative mechanism involving moisture mediated pollen grain buoyancy is proposed. Relationships with the other weather variables were...

  17. Effective Long-Distance Pollen Dispersal in Centaurea jacea

    OpenAIRE

    Albrecht, M; Duelli, P; M. K. Obrist; Müller, C.; Kleijn, D.; Schmid, B.

    2009-01-01

    Background Agri-environment schemes play an increasingly important role for the conservation of rare plants in intensively managed agricultural landscapes. However, little is known about their effects on gene flow via pollen dispersal between populations of these species. Methodology/Principal Findings In a 2-year experiment, we observed effective pollen dispersal from source populations of Centaurea jacea in restored meadows, the most widespread Swiss agri-environment scheme, to potted plant...

  18. Effective Long-Distance Pollen Dispersal in Centaurea jacea

    OpenAIRE

    Matthias Albrecht; Peter Duelli; Obrist, Martin K.; David Kleijn; Bernhard Schmid

    2009-01-01

    BACKGROUND: Agri-environment schemes play an increasingly important role for the conservation of rare plants in intensively managed agricultural landscapes. However, little is known about their effects on gene flow via pollen dispersal between populations of these species. METHODOLOGY/PRINCIPAL FINDINGS: In a 2-year experiment, we observed effective pollen dispersal from source populations of Centaurea jacea in restored meadows, the most widespread Swiss agri-environment scheme, to potted pla...

  19. Pollen Morphology of some Cultivated Varieties of Strawberry

    OpenAIRE

    Ibrahim, M. I. A. [محمد اسماعيل ابراهيم; Ibrahim, Atef; El-Naggar, Assem

    1999-01-01

    Pollen grains of twelve cultivated varieties of strawberries grown in Egypt were morphologically studied using both light microscopy and SEM observations. These varieties include eleven cultivars of Fragaria x ananassa (c.v: Capitola, Douglas, Chandler, Selva, Fern, Seascape, Dorite, Pajaro, Parker, Sequioa, Oso Grande) and one cultivar of Fragaria vesca. Pollen grains of Fragaria are spheroidal, subprolate ellipsoidal to triangular in outline. Tricolporate with long colpae tapering to pointe...

  20. All-optical automatic pollen identification: Towards an operational system

    Science.gov (United States)

    Crouzy, Benoît; Stella, Michelle; Konzelmann, Thomas; Calpini, Bertrand; Clot, Bernard

    2016-09-01

    We present results from the development and validation campaign of an optical pollen monitoring method based on time-resolved scattering and fluorescence. Focus is first set on supervised learning algorithms for pollen-taxa identification and on the determination of aerosol properties (particle size and shape). The identification capability provides a basis for a pre-operational automatic pollen season monitoring performed in parallel to manual reference measurements (Hirst-type volumetric samplers). Airborne concentrations obtained from the automatic system are compatible with those from the manual method regarding total pollen and the automatic device provides real-time data reliably (one week interruption over five months). In addition, although the calibration dataset still needs to be completed, we are able to follow the grass pollen season. The high sampling from the automatic device allows to go beyond the commonly-presented daily values and we obtain statistically significant hourly concentrations. Finally, we discuss remaining challenges for obtaining an operational automatic monitoring system and how the generic validation environment developed for the present campaign could be used for further tests of automatic pollen monitoring devices.

  1. Comparative pollen morphology of Glechoma and Marmoritis(Nepetinae,Lamiaceae)

    Institute of Scientific and Technical Information of China (English)

    Tae-Soo JANG; Suk-Pyo HONG

    2010-01-01

    The pollen morphology of 13 taxa(34 specimens)of the genera Glechoma L.,and Marmoritis Benth.was investigated in detail using light,scanning electron,and transmission electron microscopy.Pollen grains of all studied taxa are small to large in size(P = 32.5-60.4μm,E = 20.2-50.5μm),prolate-spheroidal to prolate in shape and mostly hexacolpate(the amb more or less circular or rarely ellipsoid)with granular membranes.The sexine ornamentation of Glechoma is bireticulate; the muri of the primary reticulum are irregularly circled,and lumen size is short.In contrast,the sexine surfaces of the Marmoritis pollen tend to more elongate or wider at the muri of the primary reticulum than those of the Glechoma.The pollen wall stratification of selected taxa(three from Glechoma and one from Marmoritis)is characterized by unbranched columellae,and continuous or distinctly discontinuous endexine based on transmission electron microscopy observation.The results of Glechoma and Marmoritis reveal rather similar pollen morphological features,however,fine details of sexine ornamentation are characteristic to differentiate the pollen taxa.Although these differences may be useful in establishing the taxonomic boundary between two genera,they are too weak to segregate diagnostic characters.

  2. Allergy to periwinkle pollen (Catharanthus roseus G. Don.).

    Science.gov (United States)

    Ghosh, Debajyoti; Roy, Indrani; Chanda, Sunirmal; Gupta-Bhattacharya, Swati

    2007-01-01

    Catharanthus roseus G. Don. (CR) or periwinkle plants are widely grown/ cultivated as garden plants in the tropics and subtropics. In spite of its predominantly entomophilous nature, CR pollen had been reported to be airborne and allergenic. The objective of this study was to discover the seasonal changes of CR pollen concentration in air, to determine its potential to cause respiratory allergy and to analyze its allergenic components. A 2-year aerobiological survey was conducted with a Burkard 7-day sampler in an agricultural farm in the suburban zone of Calcutta city where CR pollen was found to be almost perennial with 3.6-5.4% contribution to the aeropollen load. Skin prick test was conducted on 282 respiratory allergic individuals living within a 15 km radius of the study area. 29.8% of them were positive to CR pollen. Among them, 80.9% were directly involved in gardening. The whole pollen extract was subjected to gel filtration in a Sephacryl S-200 column. Among 5 eluted fractions, fraction I showed optimum IgE-reactivity in ELISA-inhibition. The fraction I shows 4 protein components in SDS-PAGE, within which 3 (40-66 kD molecular mass) were found to be IgE-reactive in immunoblotting using patient sera. It can be concluded that CR pollen can trigger IgEmediated respiratory allergy in the people living in close proximity.

  3. Influence of wind direction on pollen concentration in the atmosphere

    Science.gov (United States)

    Silva Palacios, I.; Tormo Molina, R.; Muñoz Rodríguez, A. F.

    The daily pollen concentration in the atmosphere of Badajoz (SW Spain) was analysed over a 6-year period (1993-1998) using a volumetric aerobiological trap. The results for the main pollination period are compared with the number of hours of wind each day in the four quadrants: 1 (NE), 2 (SE), 3 (SW) and 4 (NW). The pollen source distribution allowed 16 pollen types to be analysed as a function of their distribution in the four quadrants with respect to the location of the trap. Four of them correspond to species growing in an irrigated farmland environment (Amaranthaceae-Chenopodiaceae, Plantago, Scirpus, and Typha), five to riparian and woodland species (Salix, Fraxinus, Alnus, Populus, and Eucalyptus), four to urban ornamentals (Ulmus, Arecaceae, Cupressaceae, and Casuarina), and three which include the most frequent pollen grains of widely distributed species (Poaceae, Quercus, and Olea). The results show that the distribution of the sources and the wind direction play a very major role in determining the pollen concentration in the atmosphere when these sources are located in certain quadrants, and that the widely distributed pollen sources show no relationship with wind direction. In some years the values of the correlations were not maintained, which leads one to presume that, in order to draw significant conclusions and establish clear patterns of the influence of wind direction, a continuous and more prolonged study will be required.

  4. Temperature sensitivity of a numerical pollen forecast model

    Science.gov (United States)

    Scheifinger, Helfried; Meran, Ingrid; Szabo, Barbara; Gallaun, Heinz; Natali, Stefano; Mantovani, Simone

    2016-04-01

    Allergic rhinitis has become a global health problem especially affecting children and adolescence. Timely and reliable warning before an increase of the atmospheric pollen concentration means a substantial support for physicians and allergy suffers. Recently developed numerical pollen forecast models have become means to support the pollen forecast service, which however still require refinement. One of the problem areas concerns the correct timing of the beginning and end of the flowering period of the species under consideration, which is identical with the period of possible pollen emission. Both are governed essentially by the temperature accumulated before the entry of flowering and during flowering. Phenological models are sensitive to a bias of the temperature. A mean bias of -1°C of the input temperature can shift the entry date of a phenological phase for about a week into the future. A bias of such an order of magnitude is still possible in case of numerical weather forecast models. If the assimilation of additional temperature information (e.g. ground measurements as well as satellite-retrieved air / surface temperature fields) is able to reduce such systematic temperature deviations, the precision of the timing of phenological entry dates might be enhanced. With a number of sensitivity experiments the effect of a possible temperature bias on the modelled phenology and the pollen concentration in the atmosphere is determined. The actual bias of the ECMWF IFS 2 m temperature will also be calculated and its effect on the numerical pollen forecast procedure presented.

  5. Pollen morphology of Rhododendron subgen. Tsutsusi and its systematic implications

    Institute of Scientific and Technical Information of China (English)

    Yue-Jiao ZHANG; Xiao-Feng JIN; Bing-Yang DING; Jing-Ping ZHU

    2009-01-01

    Eighty-four pollen samples were obtained for 80 taxa, of which, 13 species and one variety are from sect. Brachycalyx Sweet, 58 species and two varieties from sect. Tsutsusi Sweet, and six species from subgen. Pentanthera (G. Don) Pojarkova, respectively. Pollen morphology of all samples was observed using LM and SEM. Pollen grains are revealed to be spheroidal and tetrahedral with tricolporate apertures. Pollen sizes of sub-gen. Tsutsusi (Sweet) Pojarkova range from 37.67 μm to 61.06 μm, and the exine sculptures are more or less compactly granulated. Pollen sizes are significantly different between sect. Brachycalyx and sect. Tsutsusi of subgen. Tsutsusi. Rhododendron tashiroi Maxim. of sect. Tsusiopsis Sleumer shows a close affinity to sect. Brachycalyx. Pollen size and exine are consistent with general morphology in differentiating species in sect. Tsutsusi. Rhododendron huadingense B. Y. Ding & Y. Y. Fang, once placed as a member of sect. Brachycalyx, should be considered as a species in subgen. Pentanthera.

  6. Pollen-Ovule Ratio and Gamete Investment in Pedicularis (Orobanchaceae)

    Institute of Scientific and Technical Information of China (English)

    Chun-Feng Yang; You-Hao Guo

    2007-01-01

    The Pedicularis species provides ideal materials to study floral evolution because of their substantial flower variation based on a narrow genetic basis, even though they are almost exclusively pollinated by bumblebee.These traits allow us to detect the evolutionary trends of floral parameters without considering genetic background and the difference of pollination vectors. The pollen-ovule ratio is widely used to estimate the pattern of resource investment in two sexual functions in flowering plants. Forty species representing all of the corolla types in Pedicularis were used to study pollen-ovule ratio, gamete investment, and their correlations. Results show that pollen-ovule ratio does not differ among both different corolla types and taxonomic groups. It is therefore suggested that pollen-ovule ratio should be a parallel evolution. The correlations between pollen-ovule ratio and pollen size (-), and ovule size (+) can be successfully explained in terms of sex allocation theory. The biological significance of such relationships was also discussed. Additionally, we analyzed the pattern of resource investment into female gamete, which has been somewhat neglected, and found that plants have different patterns of gamete investment between the two sexual functions.

  7. Securing maximum diversity of Non Pollen Palynomorphs in palynological samples

    DEFF Research Database (Denmark)

    Enevold, Renée; Odgaard, Bent Vad

    2015-01-01

    Palynology is no longer synonymous with analysis of pollen with the addition of a few fern spores. A wide range of Non Pollen Palynomorphs are now described and are potential palaeoenvironmental proxies in the palynological surveys. The contribution of NPP’s has proven important to the interpreta......Palynology is no longer synonymous with analysis of pollen with the addition of a few fern spores. A wide range of Non Pollen Palynomorphs are now described and are potential palaeoenvironmental proxies in the palynological surveys. The contribution of NPP’s has proven important.......g. Schulz & Shumilovskikh 2013). Increasingly it has become customary for palynologists to quantify at least some of the NPP’s appearing on the pollen slides (e.g. Strother et al. 2015, Odgaard 1994). Are these samples representative of the initial NPP assemblages? The usual sample preparation method...... for pollen analysis is based on acetylization (Erdtman 1969) and HF-treatment which are of variable destructiveness to the NPP’s. Some NPP’s might completely vanish and the prepared sample might hold less NPP diversity than the initial NPP assemblage. Consequently, it may be advisable to consider...

  8. Contrasting short-term performance of mountain birch (Betula pubescens ssp. czerepanovii treeline along a latitudinal continentality-maritimity gradient in the southern Swedish Scandes

    Directory of Open Access Journals (Sweden)

    Lisa Öberg

    2012-01-01

    Full Text Available Positional treeline shift is a fundamental aspect and indicator of high-mountain vegetation response to climate change. This study analyses treeline performance during the period 2005/2007 -2010/2011 in the Swedish Scandes. Focus is on mountain birch (Betula pubescens ssp. czerepanovii along a regional climatic maritimity-continentality gradient. Treeline upshift by 3.0 yr-1 in the maritime part differed significantly from retreat by 0.4 m yr-1 in the continental part of the transect. This discrepancy is discussed in terms of differential warming-induced snow cover phenology patterns and their influence on soil moisture conditions. In the continental area, earlier and more complete melting of prior relatively rare late-lying snow patches, even high above the treeline, has progressed to a state when melt water irrigation ceases. As a consequence, soil drought sets back the vigor of existing birches and precludes sexual regeneration and upslope advance of the treeline. In the maritime area, extensive and deep snow packs still exist above the treeline and constrain its position, although some release is taking place in the current warm climate. Thereby, the birch treeline expands upslope as the alpine snow patches shrink, but continue to provide sufficient melt water throughout the summer. Treeline rise appears to have been based primarily on seed regeneration over the past few decades. This is a novelty, since prior (1915-2007 treeline advance was accomplished mainly by in situ shifts in growth form of relict krummholz birches, in some cases millennial-old, prevailing above the treeline. By the snow phenology mechanism, birch can benefit from climate warming in the maritime region, which contrasts with the situation in the continental region. This discrepancy should be accounted for in projective models. In a hypothetical case of sustained warming, the subalpine birch forest belt may expand less extensively than often assumed, although advance may

  9. Ecological role of reindeer summer browsing in the mountain birch (Betula pubescens ssp. czerepanovii) forests: effects on plant defense, litter decomposition, and soil nutrient cycling.

    Science.gov (United States)

    Stark, Sari; Julkunen-Tiitto, Riitta; Kumpula, Jouko

    2007-03-01

    Mammalian herbivores commonly alter the concentrations of secondary compounds in plants and, by this mechanism, have indirect effects on litter decomposition and soil carbon and nutrient cycling. In northernmost Fennoscandia, the subarctic mountain birch (Betula pubescens ssp. czerepanovii) forests are important pasture for the semidomestic reindeer (Rangifer tarandus). In the summer ranges, mountain birches are intensively browsed, whereas in the winter ranges, reindeer feed on ground lichens, and the mountain birches remain intact. We analyzed the effect of summer browsing on the concentrations of secondary substances, litter decomposition, and soil nutrient pools in areas that had been separated as summer or winter ranges for at least 20 years, and we predicted that summer browsing may reduce levels of secondary compounds in the mountain birch and, by this mechanism, have an indirect effect on the decomposition of mountain birch leaf litter and soil nutrient cycling. The effect of browsing on the concentration of secondary substances in the mountain birch leaves varied between different years and management districts, but in some cases, the concentration of condensed tannins was lower in the summer than in the winter ranges. In a reciprocal litter decomposition trial, both litter origin and emplacement significantly affected the litter decomposition rate. Decomposition rates were faster for the litter originating from and placed into the summer range. Soil inorganic nitrogen (N) concentrations were higher in the summer than in the winter ranges, which indicates that reindeer summer browsing may enhance the soil nutrient cycling. There was a tight inverse relationship between soil N and foliar tannin concentrations in the winter range but not in the summer range. This suggests that in these strongly nutrient-limited ecosystems, soil N availability regulates the patterns of resource allocation to condensed tannins in the absence but not in the presence of browsing.

  10. Impact of cytomixis on meiosis, pollen viability and pollen size in wild populations of Himalayan poppy (Meconopsis aculeata Royle)

    Indian Academy of Sciences (India)

    V K Singhal; Puneet Kumar

    2008-09-01

    We report the occurrence of cytomixis in wild populations of Himalayan poppy (Meconopsis aculeata Royle), which is considered to be an important and threatened medicinal plant growing in the high hills of the Himalayas. The impact of cytomixis on meiotic behaviour, reduced pollen viability and heterogeneous-sized pollen grains was also studied. Cytological studies in the seven wild populations from the high hills of Himachal Pradesh revealed that all the Himalayan populations exist uniformly at the tetraploid level (2n=56) on x=14. The phenomenon of chromatin transfer among the proximate pollen mother cells (PMCs) in six populations caused various meiotic abnormalities. Chromatin transfer also resulted in the formation of coenocytes, aneuploid, polyploid and anucleated PMCs. Among individuals that showed chromatin transfer, chromosome stickiness and interbivalent connections were frequently observed in some PMCs. The phenomenon of cytomixis in the species seems to be directly under genetic control; it affects the meiotic course considerably and results in reduced pollen viability.

  11. Viable suspensions of maize (Zea mays L.) pollen with exogenous DNA

    Energy Technology Data Exchange (ETDEWEB)

    Broglia, M. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Innovazione

    1996-12-01

    A viable suspension of maize pollen in aqueous medium containing exogenous DNA would be a suitable tool in attempting maize genetic transformation via pollen grains by different techniques. In this work the effects of addition of DNA to hypertonic aqueous media able to preserve maize pollen viability were investigated. An almost total loss of viability was found when pollen was incubated with native DNA in water or sucrose medium due to the immediate sticking of DNA on the pollen wall. Calcium in the incubation medium avoided DNA sticking preserving pollen fertilization ability. Pre-washing of pollen in hypertonic sucrose solution was proved to remove DNA binding components from the pollen wall. PEG 20%, that is known to inhibit pollen, and silk nucleases, was also used instead of sucrose, without any reduction in the seed-set yields.

  12. Pollen tube branching in the ovary of five species of Oenothera

    Directory of Open Access Journals (Sweden)

    Renata Śnieżko

    2014-02-01

    Full Text Available Flowers of Oenothera hookeri Torr. et Gray, Oe. brevistylis and Oe. lamarkiana de Vries were pollinated after anthesis by insects. Oe. biennis L., Oe. suaveolens Desf and sulfurea were selfpollinated in the buds. Pollen morphology was slightly different: Oe. hookeri have regular, triporated pollen, often germinating through two pores; in Oe. suaveolens many pollen grains had callose patches on the intine; in Oe. brevistylis tetraporated pollen were more often than in other species; in Oe. lamarckiana many pollen grains were empty; in Oe. biennis and Oe. suaveolens pollen grain size and viability varied. The pollen tube growth and fertilization were similar in 5 species and can be considered as typical for Oenothera. In the ovary pollen tubes branched and changed their growth direction. Near micropyle they formed short branches to the inner integument. In the nucellus the pollen tube became swollen.

  13. Screening for High-Temperature Tolerant Cotton Cultivars by Testing In Vitro Pollen Germination, Pollen Tube Growth and Boll Retention

    Institute of Scientific and Technical Information of China (English)

    Zhi Liu; You-Lu Yuan; Shao-Qing Liu; Xiao-Nan Yu; Li-Qun Rao

    2006-01-01

    With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major influence on crop production. In the cotton (Gossypium hirsutum L.)-growing areas of China, especially in the Yangtze River valley, unexpected periodic episodes of extreme heat stress usually occur in July and August, the peak time of cotton flowering and boll loading, resulting in lower boll set and lint yield. Breeding programs for screening high temperature-tolerant cotton germplasm and cultivars are urgent in order to stabilize yield in the current and future warmer weather conditions. In the present study, 14 cotton cultivars were quantified for in vitro pollen germination and pollen tube growth in response to temperatures ranging from 10 to 50 ℃ at 5 ℃ intervals. Different cotton genotypes varied in their in vitro pollen germination and pollen tube length responses to the different temperatures. Maximum pollen germination and pollen tube length ranged from 25.2% to 56.2% and from 414 to 682 μm, respectively.The average cardinal temperatures (Tmin, Topt, and Tmax) also varied among the 14 cultivars and were 11.8,27.3, and 42.7 ℃ for pollen germination and 11.8, 27.8, and 44.1 ℃ for maximum pollen tube length. Variations in boll retention and boll numbers per plant in field experiments were found for the 14 cotton cultivars and the boll retention and boll retained per plant on 20 August varied considerably in different years according to weather conditions. Boll retention on 20 August was highly correlated with maximum pollen germination (R2=0.84) and pollen tube length (R2=0.64). A screening method based on principle component analysis of the combination of pollen characteristics in an in vitro experiment and boll retention testing in the field environment was used in the present study and, as a result, the 14 cotton cultivars could be classified as tolerant, moderately tolerant, moderately susceptible and susceptible to high

  14. Bias to pollen odors is affected by early exposure and foraging experience.

    Science.gov (United States)

    Arenas, A; Farina, W M

    2014-07-01

    In many pollinating insects, foraging preferences are adjusted on the basis of floral cues learned at the foraging site. In addition, olfactory experiences gained at early adult stages might also help them to initially choose food sources. To understand pollen search behavior of honeybees, we studied how responses elicited by pollen-based odors are biased in foraging-age workers according to (i) their genetic predisposition to collect pollen, (ii) pollen related information gained during foraging and (iii) different experiences with pollen gained at early adult ages. Bees returning to the hive carrying pollen loads, were strongly biased to unfamiliar pollen bouquets when tested in a food choice device against pure odors. Moreover, pollen foragers' orientation response was specific to the odors emitted by the pollen type they were carrying on their baskets, which suggests that foragers retrieve pollen odor information to recognize rewarding flowers outside the hive. We observed that attraction to pollen odor was mediated by the exposure to a pollen diet during the first week of life. We did not observe the same attraction in foraging-age bees early exposed to an artificial diet that did not contain pollen. Contrary to the specific response observed to cues acquired during foraging, early exposure to single-pollen diets did not bias orientation response towards a specific pollen odor in foraging-age bees (i.e. bees chose equally between the exposed and the novel monofloral pollen odors). Our results show that pollen exposure at early ages together with olfactory experiences gained in a foraging context are both relevant to bias honeybees' pollen search behavior.

  15. IRREGULAR POLLEN EXINE1 Is a Novel Factor in Anther Cuticle and Pollen Exine Formation1[OPEN

    Science.gov (United States)

    Chen, Xiaoyang; Zhang, Hua; Luo, Hongbing; Zhao, Li; Dong, Zhaobin; Yan, Shuangshuang; Liu, Renyi; Xu, Chunyan; Li, Song; Chen, Huabang

    2017-01-01

    Anther cuticle and pollen exine are protective barriers for pollen development and fertilization. Despite that several regulators have been identified for anther cuticle and pollen exine development in rice (Oryza sativa) and Arabidopsis (Arabidopsis thaliana), few genes have been characterized in maize (Zea mays) and the underlying regulatory mechanism remains elusive. Here, we report a novel male-sterile mutant in maize, irregular pollen exine1 (ipe1), which exhibited a glossy outer anther surface, abnormal Ubisch bodies, and defective pollen exine. Using map-based cloning, the IPE1 gene was isolated as a putative glucose-methanol-choline oxidoreductase targeted to the endoplasmic reticulum. Transcripts of IPE1 were preferentially accumulated in the tapetum during the tetrad and early uninucleate microspore stage. A biochemical assay indicated that ipe1 anthers had altered constituents of wax and a significant reduction of cutin monomers and fatty acids. RNA sequencing data revealed that genes implicated in wax and flavonoid metabolism, fatty acid synthesis, and elongation were differentially expressed in ipe1 mutant anthers. In addition, the analysis of transfer DNA insertional lines of the orthologous gene in Arabidopsis suggested that IPE1 and their orthologs have a partially conserved function in male organ development. Our results showed that IPE1 participates in the putative oxidative pathway of C16/C18 ω-hydroxy fatty acids and controls anther cuticle and pollen exine development together with MALE STERILITY26 and MALE STERILITY45 in maize. PMID:28049856

  16. Millennial-scale vegetation changes in the north-eastern Russian Arctic during the Pliocene/Pleistocene transition (2.7-2.5 Ma) inferred from the pollen record of Lake El'gygytgyn

    Science.gov (United States)

    Andreev, Andrei A.; Tarasov, Pavel E.; Wennrich, Volker; Melles, Martin

    2016-09-01

    The sediment record of Lake El'gygytgyn (67°30‧N, 172°05‧E) spans the past 3.6 Ma and provides unique opportunities for qualitative and quantitative reconstructions of the regional paleoenvironmental history of the terrestrial Arctic. Millennial-scale pollen studies of the sediments that accumulated during the Late Pliocene and Early Pleistocene (ca. 2.7 to 2.5 Ma) demonstrate orbitally-driven vegetation and climate changes during this transitional interval. Pollen spectra show a significant vegetation shift at the Pliocene/Pleistocene boundary that is, however, delayed by a few thousand years compared to lacustrine response. About 2.70-2.68 Ma the vegetation at Lake El'gygytgyn, currently a tundra area was mostly dominated by larch forests with some shrub pine, shrub alder and dwarf birch in understory. During the marine isotope stages G3 and G1, ca. 2.665-2.647 and 2.625-2.617 Ma, some spruce trees grew in the local larch-pine forests, pointing to relatively warm climate conditions. At the beginning of the Pleistocene, around 2.588 Ma, a prominent climatic deterioration led to a change from larch-dominated forests to predominantly treeless steppe- and tundra-like habitats. Between ca. 2.56-2.53 Ma some climate amelioration is reflected by the higher presence of coniferous taxa (mostly pine and larch, but probably also spruce) in the area. After 2.53 Ma a relatively cold and dry climate became dominant again, leading to open steppe-like and shrubby environments followed by climate amelioration between ca. 2.510 and 2.495 Ma, when pollen assemblages show that larch forests with dwarf birch and shrub alder still grew in the lake's vicinity. Increased contents of green algae colonies (Botryococcus) remains and Zygnema cysts around 2.691-2.689, 2.679-2.677, 2.601-2.594, 2.564-2.545, and 2.532-2.510 Ma suggest a spread of shallow-water environments most likely due to a lake-level lowering. These events occurred simultaneously with dry climate conditions inferred

  17. Quantification of overnight movement of birch (Betula pendula branches and foliage with short interval terrestrial laser scanning

    Directory of Open Access Journals (Sweden)

    Eetu ePuttonen

    2016-02-01

    Full Text Available The goal of the study was to determine circadian movements of silver birch (Petula Bendula branches and foliage detected with terrestrial laser scanning (TLS. The study consisted of two geographically separate experiments conducted in Finland and in Austria. Both experiments were carried out at the same time of the year and under similar outdoor conditions. Experiments consisted of 14 (Finland and 77 (Austria individual laser scans taken between sunset and sunrise. The resulting point clouds were used in creating a time series of branch movements. In the Finnish data, the vertical movement of the whole tree crown was monitored due to low volumetric point density. In the Austrian data, movements of manually selected representative points on branches were monitored. The movements were monitored from dusk until morning hours in order to avoid daytime wind effects. The results indicated that height deciles of the Finnish birch crown had vertical movements between -10.0 and 5.0 cm compared to the situation at sunset. In the Austrian data, the maximum detected representative point movement was 10.0 cm. The temporal development of the movements followed a highly similar pattern in both experiments, with the maximum movements occurring about an hour and a half before (Austria or around (Finland sunrise. The results demonstrate the potential of terrestrial laser scanning measurements in support of chronobiology.

  18. Leaf surface lipophilic compounds as one of the factors of silver birch chemical defense against larvae of gypsy moth.

    Directory of Open Access Journals (Sweden)

    Vyacheslav V Martemyanov

    Full Text Available Plant chemical defense against herbivores is a complex process which involves a number of secondary compounds. It is known that the concentration of leaf surface lipophilic compounds (SLCs, particularly those of flavonoid aglycones are increased with the defoliation treatment of silver birch Betula pendula. In this study we investigated how the alteration of SLCs concentration in the food affects the fitness and innate immunity of the gypsy moth Lymantria dispar. We found that a low SLCs concentrations in consumed leaves led to a rapid larval development and increased females' pupae weight (= fecundity compared to larvae fed with leaves with high SLCs content. Inversely, increasing the compounds concentration in an artificial diet produced the reverse effects: decreases in both larval weight and larval survival. Low SLCs concentrations in tree leaves differently affected larval innate immunity parameters. For both sexes, total hemocytes count in the hemolymph increased, while the activity of plasma phenoloxidase decreased when larvae consume leaves with reduced content of SLCs. Our results clearly demonstrate that the concentration of SLCs in silver birch leaves affects not only gypsy moth fitness but also their innate immune status which might alter the potential resistance of insects against infections and/or parasitoids.

  19. A Preliminary Pharmacokinetic Study of Betulin, the Main Pentacyclic Triterpene from Extract of Outer Bark of Birch (Betulae alba cortex

    Directory of Open Access Journals (Sweden)

    Melanie N. Laszczyk

    2008-12-01

    Full Text Available During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 μg/mL respectively, for pharmacokinetic studies it was suspended in sesame oil (rats, i.p. and PEG 400 / 0.9 % NaCl (dogs, s.c.. I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 μg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 μg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p. and dogs (s.c.. In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.

  20. Genome-scale transcriptome analysis in response to nitric oxide in birch cells: implications of the triterpene biosynthetic pathway.

    Directory of Open Access Journals (Sweden)

    Fansuo Zeng

    Full Text Available Evidence supporting nitric oxide (NO as a mediator of plant biochemistry continues to grow, but its functions at the molecular level remains poorly understood and, in some cases, controversial. To study the role of NO at the transcriptional level in Betula platyphylla cells, we conducted a genome-scale transcriptome analysis of these cells. The transcriptome of untreated birch cells and those treated by sodium nitroprusside (SNP were analyzed using the Solexa sequencing. Data were collected by sequencing cDNA libraries of birch cells, which had a long period to adapt to the suspension culture conditions before SNP-treated cells and untreated cells were sampled. Among the 34,100 UniGenes detected, BLASTX search revealed that 20,631 genes showed significant (E-values≤10-5 sequence similarity with proteins from the NR-database. Numerous expressed sequence tags (i.e., 1374 were identified as differentially expressed between the 12 h SNP-treated cells and control cells samples: 403 up-regulated and 971 down-regulated. From this, we specifically examined a core set of NO-related transcripts. The altered expression levels of several transcripts, as determined by transcriptome analysis, was confirmed by qRT-PCR. The results of transcriptome analysis, gene expression quantification, the content of triterpenoid and activities of defensive enzymes elucidated NO has a significant effect on many processes including triterpenoid production, carbohydrate metabolism and cell wall biosynthesis.

  1. Nutrient supply has greater influence than sink strength on photosynthetic adaptation to CO2 elevation in white birch seedlings.

    Science.gov (United States)

    Zhang, Shouren; Dang, Qing-Lai; Cao, Bing

    2013-04-01

    To study the effects of source-sink ratio and nutrient supply on photosynthetic acclimation to CO(2) elevation, we subjected white birch seedlings to two levels of nutrient supply (high vs. low) and CO(2) concentrations (ambient vs. doubled [CO(2)]) for two months and then shaded the lower canopy on half of the seedlings to reduce source/sink ratio for an additional month. The CO(2) elevation significantly increased P(n) and IWUE at both nutrient levels but the increase was greater in the high than low nutrient treatment. The CO(2) elevation resulted in a down-regulation of V(cmax) in the low nutrient treatment but up-regulation of J(max), TPU, [Formula: see text] and J(c) in the high nutrient after 3 months of treatment. Both the CO(2) elevation and high nutrient supply increased the partition of total electron transport to carboxylation at the expense of oxidation. The seedlings responded to the shading of the lower canopy by reducing biomass allocation to roots rather than making physiological adjustments to unshaded leaves in the upper canopy. Our results suggest that the direction of photosynthetic acclimation to CO(2) elevation in white birch was nutrient-dependent and an increase in sink strength could reduce the feedback inhibition of photosynthesis.

  2. How does solar ultraviolet-B radiation improve drought tolerance of silver birch (Betula pendula Roth.) seedlings?

    Science.gov (United States)

    Robson, T Matthew; Hartikainen, Saara M; Aphalo, Pedro J

    2015-05-01

    We hypothesized that solar ultraviolet (UV) radiation would protect silver birch seedlings from the detrimental effects of water stress through a coordinated suite of trait responses, including morphological acclimation, improved control of water loss through gas exchange and hydraulic sufficiency. To better understand how this synergetic interaction works, plants were grown in an experiment under nine treatment combinations attenuating ultraviolet-A and ultraviolet-B (UVB) from solar radiation together with differential watering to create water-deficit conditions. In seedlings under water deficit, UV attenuation reduced height growth, leaf production and leaf length compared with seedlings receiving the full spectrum of solar radiation, whereas the growth and morphology of well-watered seedlings was largely unaffected by UV attenuation. There was an interactive effect of the treatment combination on water relations, which was more apparent as a change in the water potential at which leaves wilted or plants died than through differences in gas exchange. This suggests that changes occur in the cell wall elastic modulus or accumulation of osmolites in cells under UVB. Overall, the strong negative effects of water deficit are partially ameliorated by solar UV radiation, whereas well-watered silver birch seedlings are slightly disadvantaged by the solar UV radiation they receive.

  3. Effective long-distance pollen dispersal in Centaurea jacea.

    Directory of Open Access Journals (Sweden)

    Matthias Albrecht

    Full Text Available BACKGROUND: Agri-environment schemes play an increasingly important role for the conservation of rare plants in intensively managed agricultural landscapes. However, little is known about their effects on gene flow via pollen dispersal between populations of these species. METHODOLOGY/PRINCIPAL FINDINGS: In a 2-year experiment, we observed effective pollen dispersal from source populations of Centaurea jacea in restored meadows, the most widespread Swiss agri-environment scheme, to potted plants in adjacent intensively managed meadows without other individuals of this species. Potted plants were put in replicated source populations at 25, 50, 100 m and where possible 200 m distance from these source populations. Pollen transfer among isolated plants was prevented by temporary bagging, such that only one isolated plant was accessible for flower visitors at any one time. Because C. jacea is self-incompatible, seed set in single-plant isolates indicated insect mediated effective pollen dispersal from the source population. Seed set was higher in source populations (35.7+/-4.4 than in isolates (4.8+/-1.0. Seed set declined from 18.9% of that in source populations at a distance of 25 m to 7.4% at 200 m. At a distance of 200 m seed set was still significantly higher in selfed plants, indicating long-distance effective pollen dispersal up to 200 m. Analyses of covariance suggested that bees contributed more than flies to this long-distance pollen dispersal. We found evidence that pollen dispersal to single-plant isolates was positively affected by the diversity and flower abundance of neighboring plant species in the intensively managed meadow. Furthermore, the decline of the dispersal was less steep when the source population of C. jacea was large. CONCLUSIONS: We conclude that insect pollinators can effectively transfer pollen from source populations of C. jacea over at least 200 m, even when "recipient populations" consisted of single-plant isolates

  4. Fullerene fine particles adhere to pollen grains and affect their autofluorescence and germination

    Directory of Open Access Journals (Sweden)

    Aoyagi H

    2011-05-01

    Full Text Available Hideki Aoyagi, Charles U UgwuLife Science and Bioengineering, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, JapanAbstract: Adhesion of commercially produced fullerene fine particles to Cryptomeria japonica, Chamaecyparis obtusa and Camellia japonica pollen grains was investigated. The autofluorescence of pollen grains was affected by the adhesion of fullerene fine particles to the pollen grains. The degree of adhesion of fullerene fine particles to the pollen grains varied depending on the type of fullerene. Furthermore, germination of Camellia japonica pollen grains was inhibited by the adhesion of fullerene fine particles.Keywords: Cryptomeria japonica, Chamaecyparis obtusa, Camellia japonica, autofluorescence, pollen grains, fullerene fine particle

  5. Calcium in pollen-pistil interaction in `Petunia hybrida Hor`. Pt. 1. Localization of Ca{sup 2+} ions in mature pollen grain using pyroantimonate and autoradiographic methods

    Energy Technology Data Exchange (ETDEWEB)

    Bednarska, E.; Butowt, R. [Uniwersytet Mikolaja Kopernika, Torun (Poland)

    1994-12-31

    The localization of Ca{sup 2+} in the mature pollen grain and the flow of these ions the somatic tissues of the anther to the pollen grains has been studied using pyroantimonate and autoradiographic methods. In the pollen grain, Ca{sup 2+} ions have been localized in the sporoderm in the cytoplasmic vesicles of probably dictyosomal origin. Calcium ions were transported into the sporoderm together with the compounds of degenerating tapetum. The material of degenerating tapetum forms pollen coat surrounding the mature pollen grains. (author). 18 refs, 9 figs.

  6. Characterization of an endo-1,4-β-glucanase from Lilium longiflorum that functioned in pollen germination and pollen tube growth

    Institute of Scientific and Technical Information of China (English)

    SHEN MouHua; CAO QingQin; LI YiQin

    2008-01-01

    Endo-β-glucanases play vital roles in the regulation of pollen tube growth. Here, a previously identified endo-1,4-β-glucanase from Lilium Iongiflorum (lily), named LlpCell, was expressed in Escherichia coli, purified, and further investigated for its physiological function. The recombinant LIpCel1 protein hydrolyzed carboxy-methylcellulose (CMC) and exhibited activity towards laminarin from Eisenia. arborea and 1,3:1,4-β-glucan of barley. The pH for the optimum activity was 6.0 and the value of Km calculated from CMC was 5.0 mg/mL. Adding EDTA resulted in the total loss of the enzymatic activity, and this effect could be restored by the addition of Ca2+. Western blotting analysis showed that LIpCel1 protein was present in pollen grains and rehydrated pollen grains, and the amount of the protein was increased during pollen germinating, but not in the pollen tube. Consistently, the immunofluorescence labeling study with the antibody against LIpCell also indicated the presence of LIpCel1 at the beginning of germination, but not in the elongating pollen tube. Furthermore, incubation of LIpCel1 with pollen at the beginning of pollen germination increased the germination percentage and the length of pollen tube. All of these results suggested that LIpCell could play an important role in the regulation of lily pollen germination and the initiation of pollen tube growth.

  7. Holocene environmental changes in southern Kamchatka, Far Eastern Russia, inferred from a pollen and testate amoebae peat succession record

    Science.gov (United States)

    Klimaschewski, A.; Barnekow, L.; Bennett, K. D.; Andreev, A. A.; Andrén, E.; Bobrov, A. A.; Hammarlund, D.

    2015-11-01

    High resolution palaeoenvironmental records in Far-Eastern Russia are rare, and the Kamchatka Peninsula is among the least studied areas of the region. This paper describes a record spanning the last ca. 11,000 yr, obtained from a bog in the southern part of Kamchatka. The radiocarbon dated core was analysed for pollen, testate amoebae, charcoal and loss-on-ignition (LOI). The vegetation during the early Holocene was dominated by grasses (Poaceae), birch (Betula) and heath (Ericaceae p. p.). Around 10,300 cal yr BP there was a substantial change in the vegetation cover to shrub alder (Alnus viridis s.l.) stands with sedges and ferns (Polypodiophyta) as well as herbs such as meadow rue (Thalictrum) in the understory. In the surroundings of Utka peatlands started to form. The variations in the vegetation cover were most probably caused by climatic changes. At the beginning of sediment accumulation, before 10,300 cal yr BP, the composition of the vegetation points to cooler summers and/or decreased annual precipitation. Around 10,300 cal yr BP, changes in vegetation occurred due to rising temperatures and/or changed water regimes. Increased abundancies of dry indicating testate amoebae after 9100 cal yr BP point to intermediate to dry soil conditions. Between 8600 and 7700 cal yr BP tree alder (Alnus incana) was widely spread at the site which probably indicates optimal environmental conditions. The tephra layer at 381-384.5 cm (ca. 8500 cal yr BP) produces a strong impact on the testate amoebae assemblages. At 7700 cal yr BP there was a sudden drop of A. incana in the local vegetation. From this time on, A. incana and also A. viridis decrease continuously whereas Betula gradually increases. The upper part of the sequence (after 6300 cal yr BP) shows higher abundancies of meadowsweet (Filipendula) and sweet gale (Myrica) pollen. After 6300 cal yr BP, changes in testate amoebae demonstrate variable soil moisture conditions at the site. Between 3700 and 1800 cal yr BP

  8. Pollen and seed dispersal among dispersed plants.

    Science.gov (United States)

    Ghazoul, Jaboury

    2005-08-01

    The ecological significance of spacing among plants in contributing to the maintenance of species richness, particularly in tropical forests, has received considerable attention that has largely focussed on distance- and density-dependent seed and seedling mortality. More recently it has become apparent that plant spacing is also relevant to pollination, which often constrains seed production. While seed and seedling survival is reduced at high conspecific densities, pollination success, by contrast, is positively correlated to local conspecific density. Distance-dependent mechanisms acting on pollination and seed production have now been described for a variety of plants, with relatively isolated plants or fragmented populations generally suffering reduced fecundity due to pollen limitation. Yet there is considerable variability in the vulnerability of plant species to pollination failure, which may be a function of breeding system, life history, the pollination vector, the degree of specialisation among plants and their pollinators, and other indirect effects of habitat change acting on plants or pollinators. As reduced tree densities and population fragmentation are common outcomes of anthropogenically altered landscapes, understanding how pollination processes are affected in such degraded landscapes can inform effective conservation and management of remaining natural areas.

  9. Palinocam Network: airborne pollen vigilance in Madrid

    Directory of Open Access Journals (Sweden)

    Patricia Cervigón Morales

    2005-12-01

    Full Text Available Asthma Regional Programme started to give up in 1992 with four big areas. Palinocam network project was first set up in Madrid as a part of Asthma Regional Programme, comprised in a wider Environmental Subprogram: Palynological Network of Madrid Region (PALINOCAM NETWORK.Palynological network is a multidisciplinary organization which has been working since 1993. In that moment an Experts Committee was created with This Experts Committee is coordinated by the Public Health Institute, under the technical Direction of Faculty of Pharmacy and is integrated by all of the involved institutions. This juridical framework is completed with individual agreements signed between the Councils and the Public Health Department, and with a Collaboration Agreement signed with the Madrid ́s Complutense University Faculty of Pharmacy.This network main aim is to watch for aerobiological content in Madrid's air, for a best knowledge of patients expositions in each geographical area in en different moment. This information has a great interest for Public Health.Palinocam Network is a useful tool in Public Health for offering information of aerobiological levels by Internet and Telephonic Service yearly .In this way allergic patients, sanitarians and media can know the most frequent pollen types in each season and its airborne level.

  10. Transference of genetic information through irradiated pollen

    Energy Technology Data Exchange (ETDEWEB)

    Dryanovska, O.A. (Bylgarska Akademiya na Naukite, Sofia. Inst. po Genetika)

    1983-01-01

    Blossoms are used as mothers of two longistylous with male sterility varieties of Deva and Hera without anthocyan on the stem from L. esculentum (Mill.) (L.), which were pollinated with irradiated dallenform L. peruvianum (L.) with anthocyan on the stem, with 10 AND 200 Kr of gamma-rays, 5 and 10 min from a source of mixed (long and short) UV-rays, at a distance of 20 cm, while the control blossoms were pollinated with a mixture of other cultivated plants. Irradiation with gamma rays was carried out on a gamma device with a dose power of up to 1,500 R/m. The results show that irradiated pollen tube with the male chromatin induces gynogenesis and seconadary diploidization. It is assumed that some of the microfragments irradiated with high doses of radiation contain a functionally active gene or the genes responsible for anthocyan synthesis. These microfragments are capable of combining with the nonirradiated mother chromatin and they become involved and operate in the process of development of the mother sex cells and at the early embryogenesis, as a result of which anthocyan appears in the developing plants.

  11. Hollow Pollen Shells to Enhance Drug Delivery

    Directory of Open Access Journals (Sweden)

    Alberto Diego-Taboada

    2014-03-01

    Full Text Available Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine, made largely of cellulose, and the outer layer (exine, composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet protection to the material inside it. These microcapsule shells have many advantageous properties, such as homogeneity in size, resilience to both alkalis and acids, and the ability to withstand temperatures up to 250 °C. These hollow microcapsules have the ability to encapsulate and release actives in a controlled manner. Their mucoadhesion to intestinal tissues may contribute to the extended contact of the sporopollenin with the intestinal mucosa leading to an increased efficiency of delivery of nutraceuticals and drugs. The hollow microcapsules can be filled with a solution of the active or active in a liquid form by simply mixing both together, and in some cases operating a vacuum. The active payload can be released in the human body depending on pressure on the microcapsule, solubility and/or pH factors. Active release can be controlled by adding a coating on the shell, or co-encapsulation with the active inside the shell.

  12. Predicting tree pollen season start dates using thermal conditions.

    Science.gov (United States)

    Myszkowska, Dorota

    2014-01-01

    Thermal conditions at the beginning of the year determine the timing of pollen seasons of early flowering trees. The aims of this study were to quantify the relationship between the tree pollen season start dates and the thermal conditions just before the beginning of the season and to construct models predicting the start of the pollen season in a given year. The study was performed in Krakow (Southern Poland); the pollen data of Alnus, Corylus and Betula were obtained in 1991-2012 using a volumetric method. The relationship between the tree pollen season start, calculated by the cumulated pollen grain sum method, and a 5-day running means of maximum (for Alnus and Corylus) and mean (for Betula) daily temperature was found and used in the logistic regression models. The estimation of model parameters indicated their statistically significance for all studied taxa; the odds ratio was higher in models for Betula, comparing to Alnus and Corylus. The proposed model makes the accuracy of prediction in 83.58 % of cases for Alnus, in 84.29 % of cases for Corylus and in 90.41 % of cases for Betula. In years of model verification (2011 and 2012), the season start of Alnus and Corylus was predicted more precisely in 2011, while in case of Betula, the model predictions achieved 100 % of accuracy in both years. The correctness of prediction indicated that the data used for the model arrangement fitted the models well and stressed the high efficacy of model prediction estimated using the pollen data in 1991-2010.

  13. Meiotic aberrations during 2n pollen formation in Begonia.

    Science.gov (United States)

    Dewitte, A; Eeckhaut, T; Van Huylenbroeck, J; Van Bockstaele, E

    2010-02-01

    Unreduced gametes are the driving force for the polyploidization of plants in nature, and are also an important tool for ploidy breeding. The final heterozygosity of a 2n pollen grain depends on the cytological mechanism behind 2n pollen formation. In this study, chromosome pairing and chromosome segregation during the microsporogenesis of seven Begonia genotypes were analysed using fluorescent chromosome staining on (squashed) pollen mother cells. Among the seven genotypes, five genotypes produce 2n pollen (B. 'Bubbles', B. 'Florence Rita', B. 'Orococo', B. 'Tamo' and B276) and two genotypes produce only normal n pollen (B. fischeri and B243). All 2n pollen producers showed a mechanism equivalent to first division restitution (FDR), in which chromosomes did not segregate during meiosis I but only during meiosis II. This FDR was the result of (a) an irregular chromosome pairing in B. 'Tamo', (b) stickiness of chromosomes associated with numerous chromosome bridges in B. 'Florence Rita' and B276, and (c) a combination of irregular chromosome pairing and stickiness of chromosomes in B. 'Bubbles'. The exact mechanism of the nuclear restitution in B. 'Orococo' could not be determined. Other mechanisms, such as early asymmetric cytokinesis, omission of meiosis II, parallel or tripolar spindle formation, were rather uncommon. Unpaired chromosomes (univalents) were observed in all genotypes, but they had moved to one of the poles by the end of anaphase I or II. Only B. 'Tamo' formed a high number of micronuclei. Consequently, this genotype formed a large number of malformed pollen. Obviously, chromosome behaviour during meiosis in Begonia is very dynamic, which may have important consequences for chromosome evolution and biodiversity within the genus.

  14. Air quality biomonitoring through pollen viability of Fabaceae.

    Science.gov (United States)

    Duro, Anna; Piccione, Vincenzo; Zampino, Daniela

    2013-05-01

    In this study, pollen viability and germination of three plant species, Cercis siliquastrum L., Robinia pseudoacacia L., and Spartium junceum L., belonging to the Fabaceae family, was evaluated in sites with different intensity of road traffic, constantly monitored with continuous analysers for air pollutants (carbon monoxide (CO), sulphur dioxide (SO(2)), and nitrogen dioxide (NO(2))) by the Municipality of Catania. Two sites, in which road traffic was absent, were selected, too. The percentages of viable pollen by 2,3,5-trypheniltetrazolium chloride (TTC) test ranged from 59.0 to 90.2 % in C. siliquastrum, from 61.5 to 83.5 % in S. junceum and from 67.5 to 84.3 % in R. pseudoacacia. The percentages of germination varied from 41.0 to 72.7 % in C. siliquastrum, from 42.0 to 64.7 % in S. junceum and from 38.3 to 66.3 % in R. pseudoacacia. The highest percentages of viable pollens were found in no-road traffic stations by either TTC or germination tests, while the lowest values were detected in a site characterised by heavy road traffic. In the monitored period (2007-2009), pollen viability, germinability and tube length of C. siliquastrum resulted in a significant negative correlation to CO, SO(2) and NO(2), whereas data from TTC and germination tests on S. junceum and R. pseudoacacia pollens were not well correlated to air pollutants. The results showed that pollen viability, germination and tube growth in C. siliquastrum were affected by air pollution. S. junceum and R. pseudoacacia were not very influenced by air pollutants, suggesting a different pollen sensitivity of these species.

  15. Use of MODIS Satellite Data to Evaluate Juniperus spp. Pollen Phenology to Support a Pollen Dispersal Model, PREAM, to Support Public Health Allergy Alerts

    Science.gov (United States)

    Luvall, J. C.; Sprigg, W. A.; Levetin, E.; Huete, A. R.; Nickovic, S.; Prasad, A. K.; Pejanovic, G.; Vukovic, A.; Van De Water, P. K.; Budge, A.; Hudspeth, W. B.; Krapfl, H.; Toth, B.; Zelicoff, A.; Myers, O.; Bunderson, L.; Ponce-Campos, G.; Menache, M.; Crimmins, T. M.; Vujadinovic, M.

    2012-12-01

    Pollen can be transported great distances. Van de Water et. al., 2003 reported Juniperus spp. pollen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. The DREAM (Dust REgional Atmospheric Model, Nickovic et al. 2001) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and concentrations of dust. We are modifying the DREAM model to incorporate pollen transport. Pollen emission is based on MODIS-derived phenology of Juniperus spp. communities. Ground-based observational records of pollen release timing and quantities will be used as model verification. This information will be used to support the Centers for Disease Control and Prevention's National Environmental Public Health Tracking Program and the State of New Mexico environmental public health decision support for asthma and allergies alerts.

  16. Use of MODIS Satellite Data to Evaluate Juniperus spp. Pollen Phenology to Support a Pollen Dispersal Model, PREAM, to Support Public Health Allergy Alerts

    Science.gov (United States)

    Luvall, J. C.; Sprigg, W. A.; Levetin, E.; Huete, A.; Nickovic, S.; Prasad, A.; Pejanovic, G. A.; Vukovic, A.; VandeWater, P. K.; Budge, A. M.; Hudspeth, W.; Krapfl, H.; Toth, B.; Zelicoff, A. P.; Myers, O. B.; Bunderson, L.; Ponce-Campos, G.; Crimmins, T. M.; Menache, M.; Vujadinovic, M.

    2013-01-01

    Pollen can be transported great distances. Van de Water et. al., 2003 reported Juniperus spp. pollen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. The DREAM (Dust REgional Atmospheric Model) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and concentrations of dust. We are modifying the DREAM model to incorporate pollen transport. Pollen emission is based on MODIS-derived phenology of Juniperus spp. communities. Ground-based observational records of pollen release timing and quantities will be used as model verification. This information will be used to support the Centers for Disease Control and Prevention s National Environmental Public Health Tracking Program and the State of New Mexico environmental public health decision support for asthma and allergies alerts

  17. Subtropical grass pollen allergens are important for allergic respiratory diseases in subtropical regions

    Directory of Open Access Journals (Sweden)

    Davies Janet

    2012-03-01

    Full Text Available Abstract Background Grass pollen allergens are a major cause of allergic respiratory disease but traditionally prescribing practice for grass pollen allergen-specific immunotherapy has favoured pollen extracts of temperate grasses. Here we aim to compare allergy to subtropical and temperate grass pollens in patients with allergic rhinitis from a subtropical region of Australia. Methods Sensitization to pollen extracts of the subtropical Bahia grass (Paspalum notatum, Johnson grass (Sorghum halepense and Bermuda grass (Cynodon dactylon as well as the temperate Ryegrass (Lolium perenne were measured by skin prick in 233 subjects from Brisbane. Grass pollen-specific IgE reactivity was tested by ELISA and cross-inhibition ELISA. Results Patients with grass pollen allergy from a subtropical region showed higher skin prick diameters with subtropical Bahia grass and Bermuda grass pollens than with Johnson grass and Ryegrass pollens. IgE reactivity was higher with pollen of Bahia grass than Bermuda grass, Johnson grass and Ryegrass. Patients showed asymmetric cross-inhibition of IgE reactivity with subtropical grass pollens that was not blocked by temperate grass pollen allergens indicating the presence of species-specific IgE binding sites of subtropical grass pollen allergens that are not represented in temperate grass pollens. Conclusions Subtropical grass pollens are more important allergen sources than temperate grass pollens for patients from a subtropical region. Targeting allergen-specific immunotherapy to subtropical grass pollen allergens in patients with allergic rhinitis in subtropical regions could improve treatment efficacy thereby reducing the burden of allergic rhinitis and asthma.

  18. [Analysis of pine pollen by using FTIR, SEM and energy-dispersive X-ray analysis].

    Science.gov (United States)

    Wang, Ya-min; Wang, Hong-jie; Zhang, Zhuo-yong

    2005-11-01

    Infrared spectroscopy (IR), scanning electron microscope (SEM) and energy-dispersive X-ray analysis (EDX) were used to analyze nutrients in four pine pollen powder samples. The IR fingerprints showed that each of the samples, pinus massoniana, pinus yunnanensis, pinus tabulaeformis, and pinus densiflora, respectively had its own characteristic infrared spectrum. Based on the difference of the relative intensity of those characteristic absorption peaks, the IR fingerprints can be used for the identification of the four kinds of pine pollen samples. The broken pollen of pinus was more easily to release nutritional components for the distinct difference IR fingerprints of natural and broken masson pine pollen samples. As a result of SEM, four kinds of pollen grains were oblong or subspheroidal in distal face and proximal face. The exine sculpture of the four kinds of samples were granulous and almost the same, but there was some difference of the size of pollen grains. The main morphologic change of the broken pollen was that the air bags were separated from pollen particles, and part of the main body of pollen particles was broken. The energy-dispersive X-ray analysis results showed that eleven elements, including Mg, Se, Si, Sr, P, S, Cl, K, Ca, Mn, and Fe, existed and the highest content in pollen of pinus was K element. The contents of trace elements were different in different kinds of pollen of pinus. The element intensity in broken masson pine pollen was distinctlyhigher than that innatural masson pine pollen.

  19. Studies of modern pollen assemblages for pollen dispersal- deposition- preservation process understanding and for pollen-based reconstructions of past vegetation, climate, and human impact: A review based on case studies in China

    Science.gov (United States)

    Xu, Qinghai; Zhang, Shengrui; Gaillard, Marie-jose; Li, Manyue; Cao, Xianyong; Tian, Fang; Li, Furong

    2016-10-01

    Fossil pollen, as a direct proxy record of past vegetation, and indirect proxy record of past climate, plays an essential role in revealing and reconstructing past vegetation and climate. However, relationships between pollen, vegetation and climate are not linear, hence quantitative reconstructions of past vegetation and climate based on pollen records are not straightforward, and results may be highly contradictory and difficult to interpret. One of the main causes of discrepancies between results has been the lack of comprehensive and systematical studies on modern pollen dispersal and deposition processes, particularly on the quantification of these processes. Based on empirical studies performed in China over the last 30 years, this paper provides the state-of-the-art of the understanding of pollen dispersal and deposition processes in China and the remaining questions to be investigated. We show that major progress has been achieved in the study of modern pollen dispersal and deposition processes, and in the application of models of the pollen-vegetation-climate relationships for quantitative reconstruction of past vegetation and climate. However, several issues are not entirely solved or understood yet, such as how to quantify the reworking and re-deposition of pollen grains in quaternary alluvial sediments, the influence of pollen preservation on pollen assemblages, and human impact on vegetation. Even so, the progress made during the last decades makes it possible to achieve significantly more precise and informative reconstructions of past vegetation, land-use and climate in China than was possible earlier.

  20. Flowering phenology and potential pollen emission of three Artemisia species in relation to airborne pollen data in Poznań (Western Poland).

    Science.gov (United States)

    Bogawski, Paweł; Grewling, Łukasz; Frątczak, Agata

    Artemisia pollen is an important allergen in Europe. In Poznań (Western Poland), three Artemisia species, A. vulgaris, A. campestris and A. absinthium, are widely distributed. However, the contributions of these species to the total airborne pollen are unknown. The aim of the study was to determine the flowering phenology and pollen production of the three abovementioned species and to construct a model of potential Artemisia pollen emission in the study area. Phenological observations were conducted in 2012 at six sites in Poznań using a BBCH phenological scale. Pollen production was estimated by counting the pollen grains per flower and recalculating the totals per inflorescence, plant and population in the study area. Airborne pollen concentrations were obtained using a Hirst-type volumetric trap located in the study area. Artemisia vulgaris began to flower the earliest, followed by A. absinthium and then A. campestris. The flowering of A. vulgaris corresponded to the first peak in the airborne pollen level, and the flowering of A. campestris coincided with the second pollen peak. The highest amounts of pollen per single plant were produced by A. vulgaris and A. absinthium. A. campestris produced considerably less pollen, however, due to its common occurrence, it contributed markedly (30 %) to the summation of total of recorded pollen. A. vulgaris is the most important pollen source in Poznań, but the roles of two other Artemisia species cannot be ignored. In particular, A. campestris should be considered as an important pollen contributor and likely might be one of the main causes of allergic reactions during late summer.

  1. The Holocene paleoenvironmental history of central European Russia reconstructed from pollen, plant macrofossil, and testate amoeba analyses of the Klukva peatland, Tula region

    Science.gov (United States)

    Novenko, Elena Yu.; Tsyganov, Andrey N.; Volkova, Elena M.; Babeshko, Kirill V.; Lavrentiev, Nikita V.; Payne, Richard J.; Mazei, Yuri A.

    2015-05-01

    Holocene climatic variability and human impact on vegetation are reconstructed from a region in central European Russia, which lies at an important ecotone between broadleaf forest and steppe. For the first time in this region we adopt a multi-proxy approach that combines analysis of local mire conditions from plant macrofossil and testate amoeba analyses with pollen-based quantitative climate reconstruction. The proxies indicate a long-term warming trend from 9700 to 7500 cal yr BP, interrupted by a series of short-term cold events. From 7500 to 5000 cal yr BP the results imply a relatively stable climate, warmer and drier than present, spanning the Holocene Thermal Maximum. Since 5000 cal yr BP the data suggest a change to cooler climate, but with centennial-scale variability. This shift at around 5000 cal yr BP is supported by extensive evidence from other sites. In the early Holocene, the region was occupied mainly by pine and birch forests. Broad-leafed forests of oak, lime and elm expanded after 7800 cal yr BP and remained dominant until the last few centuries. During the historical period, vegetation changes have been driven mainly by human activities.

  2. Diagnostic value of scratch-chamber test, skin prick test, histamine release and specific IgE in birch-allergic patients with oral allergy syndrome to apple

    DEFF Research Database (Denmark)

    Osterballe, M; Scheller, R; Stahl Skov, P;

    2003-01-01

    BACKGROUND: The aim of the study was to examine the diagnostic value of skin prick test (SPT), scratch-chamber test (SCT), histamine release (HR) and specific immunoglobulin E (IgE) in birch-allergic patients with oral allergy syndrome to apple. METHODS: Ten birch-allergic patients with oral alle...... a detailed case history about symptoms of oral allergy syndrome combined with a SPT with fresh apple peel or A72 will be useful.......BACKGROUND: The aim of the study was to examine the diagnostic value of skin prick test (SPT), scratch-chamber test (SCT), histamine release (HR) and specific immunoglobulin E (IgE) in birch-allergic patients with oral allergy syndrome to apple. METHODS: Ten birch-allergic patients with oral...... allergy syndrome to apple and 10 control subjects were included. All were tested with SPT, SCT, HR and specific IgE [CAP, Pharmacia, Sweden and Magic Lite (ML), ALK-ABELLO, Denmark]. RESULTS: The SPT with apple, acetone extract of apple (A72) and commercial apple extract showed sensitivities of 0.80, 0...

  3. Host species and strain combination determine growth reduction of spruce and birch seedlings colonized by root-associated dark septate endophytes.

    Science.gov (United States)

    Reininger, Vanessa; Grünig, Christoph R; Sieber, Thomas N

    2012-04-01

    Interactions of Betula pendula and Picea abies with dark septate endophytes of the Phialocephala fortinii-Acephala applanata species complex (PAC) were studied. PAC are ubiquitous fungal root symbionts of many woody plant species but their ecological role is largely unknown. Sterile birch and spruce seedlings in monoculture and mixed culture were exposed to four PAC strains, added either singularly or paired in all possible combinations at 18°C and 23°C. Plant and fungal biomass was determined after 4 months. The most significant factors were strain and host combination. One of the strains significantly reduced biomass gain of spruce but not of birch. Plant biomass was negatively correlated with total endophytic fungal biomass in half of the strain - plant combinations. Endophytic PAC biomass was four times higher in spruce (≈ 40 mg g(-1) drw) than in birch (≈ 10 mg g(-1) drw). Competition between strains was strain-dependent with some strains significantly reducing colonization density of other strains, and, thus, attenuating adverse effects of 'pathogenic' strains on plant growth in some strain - plant combinations. Biomass gain of spruce but not of birch was significantly reduced at higher temperature. In conclusion, host, fungal genotype, colonization density and presence of a competing PAC strain were the main determining factors for plant growth.

  4. Ozone and climate - Effects of the excess of critical loads on birches and mountain plants; Ozon og klima - effekter av taalegrenseoverskridelser paa bjoerk og fjellplanter

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, L.M.

    1996-01-01

    The conference paper relates to the environmental effects of high concentrated ozone on the biomass production in Norway. The effects on birches and mountain plants from ozone together with the interaction between ozone and carbon dioxide and their influence on vegetation are discussed

  5. Pollen morphology of Rhizophora L. in Peninsular Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Mohd-Arrabe' , A. B.; Noraini, Talip Noraini [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2013-11-27

    Rhizophora L. are common mangrove genus in Peninsular Malaysia, it contains 3 species and 1 hybrid (R. apiculata Blume, R. mucronata Lam., R. stylosa Griff., R. x lamarckii Montrouz). This genus has some unique adaptation towards extreme environment. Rhizophora has looping aerial stilt-root and uniformly viviparous. The aim of this study is to investigate the variation in the pollen morphology of Rhizophora that can be related to their habitat. Methods include in this study is pollen observation under light and acetolysis method under scanning electron microscope. Pollen type of Rhizophora species studied except hybrid species is classified tricolporate, shape spheroidal based on ratio of length polar axis/ length of equatorial axis (1.03 - 1.09). The exine ornamentation is perforate-reticulate for R. apiculata and R. mucronata, while R. stylosa is perforate. For the only hybrid in Peninsular Malaysia, R. x lamarckii (R. apiculata x R. stylosa) differs from others, tricolpate with the absence of porate, shape is subprolate and exine ornamentation is reticulate and striate in equatorial region. Pollenkitt is present due to the salty and extreme environment. This may enhance the volume of pollenkitt present surrounding the pollen grains in Rhizophora for protection and adaptation purposes. Based on these findings, it is evident that pollen morphology is somehow related to its natural habitat.

  6. STIGMA RECEPTIVITY AND POLLEN VIABILITY OF Melaleuca alternifolia

    Directory of Open Access Journals (Sweden)

    Liliana Baskorowati

    2009-06-01

    Full Text Available Stigma  receptivity based on seed set and pollen  tubes growth  following controlled pollination of flowers  of different  ages was examined  in Melaleuca alternifolia. The stigma secretion during 10 days after anthesis and pollen viability under three different temperatures and five storage times were also observed. These series of research were undertaken because successful controlled pollination of M. alternifolia depends on the application of viable pollen to the receptive compatible  stigma. The objective of this research was therefore to determine the stigma receptivity and pollen viability of M. alternifolia. Results showed that the stigma receptivity began to develop  on day  one and finished  on day  seven after anthesis,  peak receptivity occurred from day three to day six. The stigma receptivity also coincides with the appearance of secretion in the stigma, occurring  from day three to day seven after anthesis. Therefore,  the time for pollination of M. alternifolia appeared to extend for  approximately 7 days after anthesis. Data for M. alternifolia showed that regardless of storage temperature, pollen  was still  viable  after 26 weeks  of storage;  results also demonstrated  that the lowest temperature  (-18oC was the best regime for long term storage.

  7. Modelling airborne concentration and deposition rate of maize pollen

    Science.gov (United States)

    Jarosz, Nathalie; Loubet, Benjamin; Huber, Laurent

    2004-10-01

    The introduction of genetically modified (GM) crops has reinforced the need to quantify gene flow from crop to crop. This requires predictive tools which take into account meteorological conditions, canopy structure as well as pollen aerodynamic characteristics. A Lagrangian Stochastic (LS) model, called SMOP-2D (Stochastic Mechanistic model for Pollen dispersion and deposition in 2 Dimensions), is presented. It simulates wind dispersion of pollen by calculating individual pollen trajectories from their emission to their deposition. SMOP-2D was validated using two field experiments where airborne concentration and deposition rate of pollen were measured within and downwind from different sized maize (Zea mays) plots together with micrometeorological measurements. SMOP-2D correctly simulated the shapes of the concentration profiles but generally underestimated the deposition rates in the first 10 m downwind from the source. Potential explanations of this discrepancy are discussed. Incorrect parameterisation of turbulence in the transition from the crop to the surroundings is probably the most likely reason. This demonstrates that LS models for particle transfer need to be coupled with air-flow models under complex terrain conditions.

  8. Pollen germination in vitro of Mexican Crataegus spp.

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    M. W. Borys

    2014-01-01

    Full Text Available The germination of pollen in vitro of 42 selections of Crataegus belonging to the cultivated group (C. pubescens (H.B.K. Steud. = C. mexicana Moc. et Sessé and wild group (probably C. nelsoni Eggleston was evaluated. The anthers size (length and width of each selection was also determined. Both attributes were determined by using undehisced anthers of flowers of the spring flowering period (dry season. The percent of germinated pollen varied from 82.4 to 94.2%, depending upon the selection; both groups of selections gave similar values of germination. The 45.83% of selections of the wild group gave from 88 to 90% of germinated pollen. The selections of cultivated group have been characterized by a wide range of pollen germination. The anther size - length and width - depended upon the selection. The plants of the cultivated group showed a larger size more frequently than those of the wild group. No correlation was found between pollen germination and anthers dimensions. The results were discussed in relation to productivity of fruits trees of the Mexican representatives included in the germplasm collection.

  9. A guided tour: Pollen tube orientation in flowering plants

    Institute of Scientific and Technical Information of China (English)

    SAUTER Margret

    2009-01-01

    Sexual reproduction in flowering plants requires that two sperm cells are delivered to the embryo sac where double fertilization of an egg cell and of a central cell results in the formation of a diploid embryo and of the triploid nutritional endosperm tissue. The immobile male gametes are delivered to the immobile female gametophyte by a single cell, the pollen tube. The pollen tube must be able to germinate on a genetically appropriate stigma and it must be directed through the transmitting tract of the style from where it must target an ovule. Moreover, the pollen tube must enter the ovule at a defined opening, the micropyle, grow toward one of the two synergids and release the two sperm cells upon contact. This complex process requires recognition events with chemically based or physically supported cell-cell communication as well as directional cues for the growing pollen tube. A number of molecules and mechanisms have been implicated in pollen tube guidance which are summarized in this review.

  10. Pollen and spores as biological recorders of past ultraviolet irradiance

    Science.gov (United States)

    Jardine, Phillip E.; Fraser, Wesley T.; Lomax, Barry H.; Sephton, Mark A.; Shanahan, Timothy M.; Miller, Charlotte S.; Gosling, William D.

    2016-12-01

    Solar ultraviolet (UV) irradiance is a key driver of climatic and biotic change. Ultraviolet irradiance modulates stratospheric warming and ozone production, and influences the biosphere from ecosystem-level processes through to the largest scale patterns of diversification and extinction. Yet our understanding of ultraviolet irradiance is limited because no method has been validated to reconstruct its flux over timescales relevant to climatic or biotic processes. Here, we show that a recently developed proxy for ultraviolet irradiance based on spore and pollen chemistry can be used over long (105 years) timescales. Firstly we demonstrate that spatial variations in spore and pollen chemistry correlate with known latitudinal solar irradiance gradients. Using this relationship we provide a reconstruction of past changes in solar irradiance based on the pollen record from Lake Bosumtwi in Ghana. As anticipated, variations in the chemistry of grass pollen from the Lake Bosumtwi record show a link to multiple orbital precessional cycles (19–21 thousand years). By providing a unique, local proxy for broad spectrum solar irradiance, the chemical analysis of spores and pollen offers unprecedented opportunities to decouple solar variability, climate and vegetation change through geologic time and a new proxy with which to probe the Earth system.

  11. [Pollen quality of Pinus pithyusa Stev. in natural stands of the South Crimea].

    Science.gov (United States)

    Koba, V P

    2005-01-01

    Results of long-term research of germination rate, vitality and dynamics of in vitro growth of P. pithyusa pollen are shown. Dynamics of pollen quality under the action of external factors has been defined.

  12. Chemical modification of coating of Pinus halepensis pollen by ozone exposure.

    Science.gov (United States)

    Naas, Oumsaad; Mendez, Maxence; Quijada, Melesio; Gosselin, Sylvie; Farah, Jinane; Choukri, Ali; Visez, Nicolas

    2016-07-01

    Pollen coating, located on the exine, includes an extractible lipid fraction. The modification of the pollen coating by air pollutants may have implications on the interactions of pollen with plant stigmas and human cells. Pinus halepensis pollen was exposed to ozone in vitro and the pollen coating was extracted with organic solvent and analyzed by GC-MS. Ozone has induced chemical changes in the coating as observed with an increase in dicarboxylic acids, short-chain fatty acids and aldehydes. 4-Hydroxybenzaldehyde was identified as the main reaction product and its formation was shown to occur both on native pollen and on defatted pollen. 4-Hydroxybenzaldehyde is very likely formed via the ozonolysis of acid coumaric-like monomers constitutive of the sporopollenin. Modification of pollen coating by air pollutants should be accounted for in further studies on effect of pollution on germination and on allergenicity.

  13. Specialist bees collect Asteraceae pollen by distinctive abdominal drumming (Osmia) or brushing (Melissodes, Svastra)

    Science.gov (United States)

    Four species of western US Osmia (Cephalosmia) bees that are Asteraceae specialists (oligoleges) were observed to employ a heretofore unappreciated, stereotypical means of collecting pollen, abdominal drumming, to gather pollen from 19 flowering species representing nine tribes of Asteraceae. Abdom...

  14. Evaluation of the botanical origin of commercial dry bee pollen load batches using pollen analysis: a proposal for technical standardization

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    Ortrud M. Barth

    2010-12-01

    Full Text Available High quality of bee pollen for commercial purpose is required. In order to attend the consumer with the best identification of the botanical and floral origin of the product, 25 bee pollen batches were investigated using two techniques of pollen grain preparation. The first started to identify pollen loads of different colors in t