Letteratura scientifica selezionata sul tema "Pollen"
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Articoli di riviste sul tema "Pollen"
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Can, I. H., A. İslam, D. S. Karasoy e E. E. Samim. "Does regional pollen load affect the prevalence of clinical allergy to those pollen groups?" Journal of Laryngology & Otology 124, n. 3 (23 novembre 2009): 297–301. http://dx.doi.org/10.1017/s0022215109991873.
Testo completoAbstract (sommario):
AbstractObjective:To test the association between clinical allergic sensitisation to pollens and the profile and load of those pollens, in Ankara, Turkey.Materials and methods:Forty-three patients with seasonal allergic rhinitis were included. Clinical sensitisation to various pollens was compared with 10-year counts of the same pollens. The ratios of sensitisation to various pollen groups, and the association between clinical sensitisation and pollen load, were investigated.Results:Grass pollen allergy was the leading cause of seasonal allergic rhinitis, followed by tree pollen allergy. In Ankara, the most common type of airborne tree pollen was salicacea; however, the commonest clinical tree pollen allergies were due to the betulaceae and fagaceae families.Conclusions:Higher concentrations of airborne pollens may not always result in a higher prevalence of clinical allergy to those pollens.
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,, Fidianinta, Ketty Suketi e Winarso D. Widodo. "Respon Perkecambahan Polen Pepaya IPB 6 dan IPB 9 terhadap Penyimpanan pada Suhu Rendah". Jurnal Hortikultura Indonesia 6, n. 1 (13 agosto 2015): 29. http://dx.doi.org/10.29244/jhi.6.1.29-36.
Testo completoAbstract (sommario):
<p>ABSTRACT</p><p>An experiment was conducted to study the germination and storability of papaya pollen IPB 6 and IPB 9 stored for 4 weeks at 3 levels of low temperature. The experiment was conducted at the Laboratory of Microtechnic and Laboratory of Biophysics and Reproductive Biology, Bogor Agricultural University in the month of April to June 2014. Three variables were observed in this experiment: the germination rate, pollen diameter, and length of pollen. The experimental results showed that storage temperature affected the three variables observed. The best germination for IPB 6 was indicated by pollen storage at 10 0C (23.1%) while for IPB 9 was indicated by pollen stored at 5 0C (30.7%). The longest pollen tube of IPB 6 after storage for 4 weeks was indicated by pollen stored at -20 0C (63 µm) while for IPB 9, indicated by pollen stored at 10 0C (47.72 µm). The experimental results showed that there was no corellation between pollen diameter and length of pollen tube with pollen germination in papaya pollen of IPB 6 dan IPB 9.</p><p>Key words: diameter pollen, pollen tube, germination, storability</p><p> </p><p>ABSTRAK</p><p>Percobaan dilakukan untuk mempelajari daya simpan dan daya berkecambah polen pepaya IPB 6 dan IPB 9 yang disimpan pada suhu 5 0C, 10 0C, dan -20 0C dengan waktu penyimpanan 0-4 minggu. Percobaan dilaksanakan di Laboratorium Mikroteknik dan Laboratorium Biofisik dan Biologi Reproduksi, Institut Pertanian Bogor pada bulan April-Juni 2014. Tiga variabel yang diamati pada percobaan ini adalah daya berkecambah, diameter polen dan panjang polen. Hasil percobaan menunjukkan bahwa suhu penyimpanan mempengaruhi ketiga variabel yang diamati. Daya berkecambah terbaik untuk pepaya IPB 6 ditunjukkan oleh polen yang disimpan pada 10 0C (23.1%)sedangkan untuk IPB 9 ditunjukkan oleh polen yang disimpan pada 5 0C (30.7%). Tabung Polen pepaya terpanjang setelah disimpan selama 4 minggu pada IPB 6 ditunjukkan oleh polen yang disimpan pada -20 0C (63 µm) sedangkan untuk IPB 9 ditunjukkan oleh polen yang disimpan pada 10 0C (47.72 µm). Hasil percobaan menunjukkan bahwa tidak ada hubungan antara diameter dan panjang tabung polen dengan daya berkecambah pada polen pepaya IPB 9 dan IPB 6.</p><p>Kata kunci: daya berkecambah, daya simpan, diameter polen, tabung polen</p>
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Rodríguez-Rajo, F. Javier, Mª Victoria Jato e Mª Carmen Seijo. "El polen de Eucalyptus y su incidencia en la atmósfera de Vigo (N.O. España)." Acta Botanica Malacitana 26 (1 dicembre 2001): 99–110. http://dx.doi.org/10.24310/abm.v26i0.7403.
Testo completoAbstract (sommario):
RESUMEN. El polen de Eucalyptus y su incidencia en la atmósfera de Vigo (N.O. España). Eucalyptus globulus Labill. es la especie arbórea de la familia Myrtaceae, más frecuente en los alrededores de la ciudad de Vigo formando abundantes y densas masas forestales. Aunque su polen se considera moderadamente alergénico, en áreas en las que, como consecuencia de repoblación forestal ocupa extensiones importantes, puede llegar a causar problemas alérgicos.Entre los años 1995 y 2000 se ha realizado el estudio aerobiológico en la ciudad de Vigo mediante un captador LANZONI VPPS 2000 situado en la margen derecha de la ría de Vigo (42°14'15"N, 8°43'30"W). La cantidad de granos de polen anual de Myrtaceae varía ampliamente, alternándose años de concentraciones bajas con otros de valores elevados que representan entre un I y un 3% del polen total anual. El valor más elevado se detectó en 1997 con 1.147 granos de polen. Se encuentra en la atmósfera de Vigo durante todo el año, aunque las concentraciones más importantes se producen generalmente durante los meses de marzo y abril. Asimismo, a lo largo del día los máximos de concentración tienen lugar entre las 15 y las 17 horas. Finalmente se ha realizado un análisis estadístico para poner de manifiesto la posible correlación existente entre las concentraciones de polen y los principales parámetros meteorológicos. El viento procedente del N-NE fue el parámetro con el que se obtuvo correlación positiva y significativa de forma constante, mientras que esta fue negativa con la humedad relativa.Palabras clave. Meteorología, Myrtaceae, Polen, Eucalyptus, Vigo.ABSTRACT. The Eucalyptus pollea and its incidence in the atmosphere of Vigo (N. W. Spain). Eucalyptus globulus Labill. is the most frequent arboreal species of the Myrtaceac family in the surroundings of the city of Vigo, and it constitues abundant and dense forestal masses. Although its pollen can be considered as a moderated allergen, in areas in which Eucalyptus was used in extended reafforestations, it can cause allergenic problems.From 1995 to 2000 a Hirst-type volumetric sampler (Hirst, 1952), LANZONI VPPS 2000 placed in the left bank of the Vigo estuary (42°14'15"N, 8°43'30"W) was used for collecting airborne pollen. From year to year important oscillations in the annual total pollen was observed, alternating years of high concentrations with other of lower values. Eucalyptus pollen counts represent a percentage that vary between I% to 3% of the total pollen, the high quantity being collected in 1997 with 1,147 pollen grains. The Myrtaceae pollen appears in the atmosphere of Vigo all over the year, although the more important concentrations are registered during March and April. Moreover, maximum daily concentrations occur between 17.00 and 18.00 hours. Finally, a statistical analysis has been carried out in order to search for the possible correlations between pollen concentration and the main meteorological parameters. The N-NE wind and relative humidity were the parameters that show the highest correlation coefficients, positive and negative respectively.Key words. Meteorology, Myrtaceae, Pollen, Eucalyptus, Vigo.
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Zhou, Ziyu, Hong Zhang, Shibonage K. Mashilingi, Chunting Jie, Baodi Guo, Yi Guo, Xiao Hu et al. "Bombus terrestris Prefer Mixed-Pollen Diets for a Better Colony Performance: A Laboratory Study". Insects 15, n. 4 (17 aprile 2024): 285. http://dx.doi.org/10.3390/insects15040285.
Testo completoAbstract (sommario):
Pollen is a major source of proteins and lipids for bumblebees. The nutritional content of pollen may differ from source plants, ultimately affecting colony development. This study investigated the foraging preferences of Bombus terrestris in regard to four pollen species, i.e., oilseed rape, wild apricot, sunflower, and buckwheat, under laboratory conditions. The results show that B. terrestris diversified their preference for pollens; the bumblebees mostly preferred wild apricot pollen, whereas sunflower pollen was the least preferred. The colonies fed on a mixed four-pollen diet, with a protein–lipid ratio of 4.55–4.86, exhibited better development in terms of the number of offspring, individual body size and colony weight. The colonies fed with buckwheat and sunflower pollens produced a significantly lower number of workers and failed to produce queen and male offspring. Moreover, wild apricot pollen had the richest protein content (23.9 g/100 g) of the four pollen species, whereas oilseed rape pollen had the highest lipid content (6.7 g/100 g), as revealed by the P:L ratios of wild apricot, sunflower, buckwheat, and oilseed rape, which were 6.76, 5.52, 3.50, and 3.37, respectively. Generally, B. terrestris showed feeding preferences regarding different pollens and a mixture of pollens, which ultimately resulted in differences in colony development. The findings of this study provide important baseline information to researchers and developers of nutritive pollen diets for bumblebees.
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Costa, Paulo Marks de Araújo, Vênia Camelo de Souza, Ivan Sérgio da Silva Oliveira, Vagner Sousa da Costa e Emerson Serafim Barros. "Pollen viability and floral biology of Mandacaru (Cereus jamacaru (DC) (Cactaceae))". Research, Society and Development 9, n. 8 (6 agosto 2020): e997986671. http://dx.doi.org/10.33448/rsd-v9i8.6671.
Testo completoAbstract (sommario):
Pollen fertility is indicated by viability, which influences the reproductive success of plants. Mandacaru is a native tree species with natural distribution in the Caatinga. The objective was to verify the pollen viability, pollen per ovule ratio and the morphological identification of the mandacaru flower (Cereus jamacaru). Ten flower buds were used and one hundred anthers of these buds, which and stained with Alexander dye on checkered glass slide and viable and non-viable pollens were accounted amount of ovule per flower bud was counted the pollen/ovule ratio. Mandacaru presented viability of 99.41% the pollen, with an average of 314,686 pollens on each flower. There were 356 pollens for each ovule, this indicates the species reproductive system for facultative autogamous and facultative xenogamics. The flower is hermaphrodite, with gynoecium measuring an average of 160.9 mm, an average of 883 ovules per flower, the androecium averaging 577 anthers per flower, 545 pollen per anther. Mandacaru has high pollen viability, with large size hermaphrodite flower, with high number of anthers and pollen contained in these anthers.
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Mondal, Swarnaditya, Biswajit Roy e Jnan Bikash Bhandari. "Taxonomic Investigation of Some Members of Fabaceae (Subfamily- Caesalpinioidae) With Special Reference to Pollen Morphology". NBU Journal of Plant Sciences 12, n. 1 (2020): 1–14. http://dx.doi.org/10.55734/nbujps.2020.v12i01.001.
Testo completoAbstract (sommario):
Palynology, the study of pollen, had a big role in taxonomic identification, paleontology and forensics. Pollens from different plants had different morphology, such as in Fabaceae. This study aimed to determine the pollen grains morphology in Fabaceae (Subfamily Caesalpinioidae). Pollen morphology of 19 plant species under 7 genera Fabaceae (Subfamily Caesalpinioidae) were examined. Fresh pollen samples were collected from 4 plant species from the North 24 Pgns, 2 plant species from South 24 Pgns, 8 plant species from Kolkata, 2 plant species from Nadia and 3 plant species from Howrah. Pollens were acetolysed following standard method and observed under Compound microscope. Pollen shapes were recorded based on the P/E ratio. In general, all these pollens were small, medium and large size. Parameters measured in this study were the types of pollen sizes, pollen shape, aperture characteristic, and ornamentation type of exine and the most common aperture type was tricolporate. The most important characters included exine ornamentation (exine ornamentation type) and Apocolpium Index.
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Guo, J. J., J. L. Ou, Z. G. Zhao e J. Zeng. "In vitro Competition of Betula alnoides Pollens from Two Types of Habitats in a Heterogeneous Landscape in South China". Silvae Genetica 63, n. 1-6 (1 dicembre 2014): 125–32. http://dx.doi.org/10.1515/sg-2014-0017.
Testo completoAbstract (sommario):
Abstract Pollens of Betula alnoides were collected in its natural forests at two types of sites with soils originated from limestone (Site L) and granite (Site G) in a heterogeneous landscape at Jingxi County, Guangxi in 2010 to 2012 to investigate whether nutritional differences between the sites influenced its pollen competition. In vitro pollen germinations were conducted separately and in pairs for these samples as well as nutrient contents of pollens and soils were measured. There was no significant difference in total nitrogen, phosphorus, potassium and calcium contents of dried pollen and in efficient ones of aqueous extracts of pollens between two types of sites although the soil nutrient contents were quite different between them, and less remarkable correlation was found between these nutrient contents of soil and pollen. The results of pollen competition of B. alnoides were much diverse among three years, it seemed that pollen-pollen interaction did not depend on site type, and might vary according to genotype and/or combination of genotypes.
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Zhao, Lin-Na, Jian-Qiang Li, Wen-Xiu Cheng, Su-Qin Liu, Zheng-Kai Gao, Xi Xu, Cai-Hua Ye e Huan-Ling You. "Simulation Palynologists for Pollinosis Prevention: A Progressive Learning of Pollen Localization and Classification for Whole Slide Images". Biology 11, n. 12 (16 dicembre 2022): 1841. http://dx.doi.org/10.3390/biology11121841.
Testo completoAbstract (sommario):
Existing API approaches usually independently leverage detection or classification models to distinguish allergic pollens from Whole Slide Images (WSIs). However, palynologists tend to identify pollen grains in a progressive learning manner instead of the above one-stage straightforward way. They generally focus on two pivotal problems during pollen identification. (1) Localization: where are the pollen grains located? (2) Classification: which categories do these pollen grains belong to? To perfectly mimic the manual observation process of the palynologists, we propose a progressive method integrating pollen localization and classification to achieve allergic pollen identification from WSIs. Specifically, data preprocessing is first used to cut WSIs into specific patches and filter out blank background patches. Subsequently, we present the multi-scale detection model to locate coarse-grained pollen regions (targeting at “pollen localization problem”) and the multi-classifiers combination to determine the fine-grained category of allergic pollens (targeting at “pollen classification problem”). Extensive experimental results have demonstrated the feasibility and effectiveness of our proposed method.
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AROGUNDADE, Oluwabunmi Okerinmola, e Hameedat O. LAWAL. "Palynological Studies of Three Taxa and One F1 Hybrid in the Genus Talinum Adans". Notulae Scientia Biologicae 10, n. 2 (29 giugno 2018): 175–81. http://dx.doi.org/10.15835/nsb10210214.
Testo completoAbstract (sommario):
Acetolysed pollen grains of Talinum paniculatum (Jacq.) Gaertn., Talinum triangulare (Jacq.) Willd. pink petals, Talinum triangulare (Jacq.) Willd. white petals and Talinum triangulare (Jacq.) Willd. pink and white petals F1 hybrid were studied in order to document their morphological structures and ascertain features of taxonomic significance among them. All the taxa have generic features which support their classification as a genus as well as distinct features which ascertain their individuality. Generic features include monad pollen unit, acolpate and monocolpate pollen grains as well as circular and ovate pollen shapes. The delimiting features include additional dyads pollen units in T. triangulare white petal and the F1 hybrid of T. triangulare pink and white petals, quadrangular pollen shape in T. paniculatum, bicolpate pollen grain in the F1 hybrid, tricolpate pollens in T. triangulare white petal and T. paniculatum, tetracolpate pollens in T. triangulare pink petal and T. paniculatum and pentacolpate pollen grains in T. paniculatum only. The shape of the pores in T. paniculatum also separated it from the varieties and hybrid of T. triangulare. Based on the pollen size, the pollens of T. paniculatum are Media (25 - 50 µm) while those of the two varieties of T. triangulare and their F1 hybrid are Magna (50 - 100 µm). The taxa of Talinum in this study can be separated based on their palynological features.
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Aswath, VivekC R., N. S. Bhandari e S. Gangola. "SEM-based study for palynological and pollen germination of Lilium longiflorum cv. Pavia". Journal of Applied Horticulture 24, n. 03 (10 marzo 2023): 302–5. http://dx.doi.org/10.37855/jah.2022.v24i03.53.
Testo completoAbstract (sommario):
Pollen is the first choice of germplasm curator, geneticist, breeder and physiologist for conservation and crop improvement programs. A pollen palynological attributes and pollen germination study of Lilium longiflorum cv., 'Pavia' was conducted using scanning electron microscope (SEM). Various morphological characteristics were studied. The results showed that pollens were much alike in ultra-morphology with elliptical to ellipsoidal shape, reticulate exine and single germination ditch. The pollen viability was tested by the wet room method with 3 dyes; Acetocarmine, TTC, Lugol's iodine and 49.66% pollen viability was recorded with Acetocarmine dye; which suggested acetocarmine stain can be as a quick test method for pollen viability. The pollen germination ability was examined at set intervals, thereby establishing the dynamics of this process for 72 hours. Pollens collected just 1 h after anthesis were recorded with highest germination (85%) compared to pollen harvested before or one day after. The suitable medium for pollen germination was 3% sucrose and 15% PEG that recorded with highest pollen germination (95%) after 72 h of inoculation. Understanding evolutionary ecology and the sterility problem and designing hybridization programmes in cross-breeding necessitates a thorough understanding of pollen morphology and viability. Pollen ultra-morphology traits could be helpful in determining the evolutionary relationship of lilies.
Tesi sul tema "Pollen"
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Capucho, Liana Carneiro 1984. "Diversidade morfológica de políades em espécies de Mimosoideae (Leguminosae) = Morphological diversity of polyads in Mimosoideae species (Leguminosae)". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315571.
Testo completoAbstract (sommario):
Orientador: Simone de Pádua TeixeiraTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-24T13:42:31Z (GMT). No. of bitstreams: 1 Capucho_LianaCarneiro_D.pdf: 7485279 bytes, checksum: b54a3fba348638fec00612447ae9cdb5 (MD5) Previous issue date: 2014
Resumo: Dentre os diversos tipos de agrupamento polínico, encontrados em 42 famílias de angiospermas, as políades são de interesse especial, pois são registradas para apenas quatro destas famílias e sua ocorrência pode ser associada a uma redução no número de grãos de pólen por antera em uma espécie. Em Leguminosae, a maior em número de espécies e a mais amplamente distribuída dentre as quatro famílias com políades, essas estruturas ocorrem na subfamília Mimosoideae. Este trabalho apresenta dados sobre a origem, o desenvolvimento e a diversidade morfológica das políades, em nível estrutural e ultraestrutural (Capítulo 1); sobre a origem do adesivo polínico em Calliandra brevipes, substância encontrada tipicamente em políades de espécies do gênero; além de dados sobre a origem e desenvolvimento da políade nesta espécie (Capítulo 2, já publicado); a morfologia e fertilidade polínica em espécies poliembriônicas de Inga (Capítulo 3); e um estudo aprofundado da morfologia incomum das políades em Parkia, em nível estrutural e ultraestrutural (Capítulo 4). As políades são estruturas peculiares e ainda muito pouco estudadas, e o presente trabalho vem prover dados essenciais para a compreensão da origem e morfologia destas estruturas, e de sua funcionalidade na reprodução de espécies da subfamília Mimosoideae em Leguminosae. Para um entendimento mais completo acerca da função, valor adaptativo e seleção dessas estruturas, com ocorrência tão restrita a determinados grupos de plantas, estudos acerca da fisiologia do pólen, interação pólen-pistilo e de viabilidade de embriões formados após a fertilização dos óvulos, são requeridos
Abstract: Among all different types of pollen aggregation, reported for 42 angiosperm families, polyads are of great interest, because they are reported for only four of these families and it is associated to a reduction on number of pollen grains per anther in a species. Among those four families, Leguminosae stands out because it is the most species-rich family and widely spread. In Leguminosae, polyads often occur in the subfamily Mimosoideae. This study highlighted new information on the origin, development and morphological diversity of the polyads, employing anatomic and ultrastructural analyses (Chapter 1); origin of pollen adhesive in Calliandra brevipes, sticky substance tipically found in Calliandra polyads, in addition to data on polyad origin and development (Chapter 2, already published); polyad morphology and fertility in polyembrionic species of Inga (Chapter 3); and a meticulous analysis of the peculiar morphology of Parkia polyads (Chapter 4). Polyads are peculiar and still not well-known structures, and this study aims to contribute with essential data for its origin and morphology understanding, and its functionality in the reproduction of species comprised by subfamily Mimosoideae, in Leguminosae. For a more complete understanding on the function, adaptive value and selection of these structures, that are restricted to certain groups of plants, studies are required on the physiology of pollen, pollen-pistil interaction and viability of embryos formed after fertilization of the ovules
Doutorado
Biologia Vegetal
Doutora em Biologia Vegetal
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Souza, Cintia Neves de. "Palinotaxonomia em espécies brasileiras de Gloxiniinae com ênfase no complexo Mandirola-Goyazia /". Jaboticabal, 2017. http://hdl.handle.net/11449/151043.
Testo completoAbstract (sommario):
Orientador: Eduardo Custódio GasparinoCoorientador: Andréa Onofre de Araújo
Banca: Maria Amélia Vitorino da Cruz-Barros
Banca: Vania Gonçalves Lourenço Esteves
Resumo: A subtribo Gloxiniinae é composta por 21 gêneros e cerca de 160 espécies. No Brasil, Gloxiniinae possui 16 espécies, distribuídas em oito gêneros, sendo três endêmicos, geralmente encontrados em afloramentos rochosos de cerrados, campos rupestres ou florestas de galeria. Foram estudados os grãos de pólen de dez espécies brasileiras de Gloxiniinae (Gesneriaceae) pertencentes aos gêneros: Chautemsia A.O.Araujo & V.C.Souza (1 sp.), Gloxinia L'Hér. (3 spp.), Goyazia Taub. (2 spp.), Mandirola Decne. (3 spp.) e Seemannia Regel (1 sp.) com o objetivo de contribuir para a caracterização taxônomica do grupo e uma melhor delimitação dos gêneros e/ou espécies, com enfoque para as populações do complexo Mandirola-Goyazia, pois os dois gêneros e as espécies incluídas nesse complexo não aparecem bem delimitados em estudos taxonômicos e trabalhos de filogenia, e essa dificuldade pode ser explicada por apresentarem distribuição simpátrica, morfologia floral e fenologia muito semelhantes. Os grãos de pólen foram acetolisados, medidos, fotografados em microscópia óptica, microscopia eletrônica de varredura e transmissão e descritos qualitativamente. Os dados quantitativos foram analisados através de estatísticas descritiva e multivariada. Para as espécies brasileiras de Gloxiniinae analisadas, foram observadas variações entre os grãos de pólen principalmente quanto ao âmbito, forma, comprimento, largura e extremidades dos colpos, presença ou não de margem, tipo de endoabertura e tipo de orname... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Gloxiniinae have 21 genera and about 160 species. In Brazil, Gloxiniinae has 16 species, distributed in eight genera, three of which are endemic, generally found in rock outcrops of cerrado, rupestrian fields or gallery forests. We studied the pollen grains of ten Brazilian Gloxiniinae (Gesneriaceae) belonging to the genera: Chautemsia A.O.Araujo & V.C.Souza (1 sp.), Gloxinia L'Hér. (3 spp.), Goyazia Taub. (2 spp.), Mandirola Decne. (3 spp.) and Seemannia Regel (1 sp.) with the aim of contributing to the taxonomic characterization of the group and a better delimitation of the genera and/or species, focusing on the Mandirola-Goyazia complex populations. The species of this complex are not well delimited in taxonomic studies and phylogeny works, and this difficulty can be explained by the sympatric distribution, and the floral morphology and phenology very similar. The pollen grains were acetolysed, measured, photographed under light microscopy, scanning and transmission electron microscopy and described qualitatively. The quantitative data were analyzed by descriptive and multivariate statistics. We observed for the Brazilian Gloxiniinae species variations on the amb, shape, length and width colpi, colpi end, margo, endoaperture and ornamentation. For the 36 natural populations of Mandirola and Goyazia, qualitative data such as number and type of apertures, endoaperture, margo, ornamentaion and exine utrastructure are very similar, but we identify differences in amb, shape, le... (Complete abstract click electronic access below)
Mestre
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Cardellach, Lliso Pau. "Análisis esporo-polínico de la miel y el propóleo, y su relación con el entorno". Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670125.
Testo completoAbstract (sommario):
Estudiar els productes d’ Apis mellifera derivats dels recursos botànics (mel, melat, pol·len i pròpoli), és útil per a caracteritzar i posar en valor els productes de l’ abella d’ un territori i per a comprendre les interaccions planta-pol·linitzador. La melisopalinologia té com a objectius la determinació geogràfica i botànica dels productes apícoles, basant-se en la presencia de tipus pol·línics (TP). El primer objectiu de la present tesi ha estat determinar quines plantes són útils per a A. mellifera a Catalunya, a través d’una revisió bibliogràfica i d’observacions in situ s’ha elaborat una llista de 424 tàxons útils, de 114 famílies. Per a l’estudi melissopalinològic de les 51 mels i els 26 pròpolis analitzats en aquesta tesi es va elaborar una palinoteca de referència en base als TP dels tàxons d’interès apícola de Catalunya. Com a resultat de l’anàlisi melissopalinològica, s’ha determinat l’origen geogràfic i botànic de les mels i els pròpolis, i s’han identificat 156 TP de 74 famílies. A través de l’anàlisi de l’espectre pol·línic de les mels, s’ han tipificat diferents tipus de mels, tant multiflorals com monoflorals, de diferents zones geogràfiques i de diferents anys. A més, l’anàlisi estadística ha mostrat l’existència de diferències significatives entre les mels urbanes i la resta de mels. A les mels no urbanes s’han identificat 131 TP. Tot i que els més freqüents són autòctons (Brassicaceae T., Coronilla T., Quercus perennifolio, Rubus T., Salix sp. y Ulex T.), l’aparició d’espècies invasores (com Ailanthus altissima) mostra la seva utilitat com a recurs apícola, i indica que cal tenir en compte a aquest tipus d’espècies a l’hora d’establir l’origen geogràfic i botànic de les mels d’ un territori. També, destacar l’elevada presència i percentatges de TP com Cistus monspeliensis, Hedera helix, Rhamnus sp. i Salix sp., que podrien servir com a indicadors per a la tipificació geogràfica de mels de Catalunya. Per altra banda, es veu reflectida la importància per a A. mellifera dels ecosistemes de tipus matollar i herbaci, així com, que les abelles de ruscs situats a la perifèria de nuclis urbans s’ endinsen a les ciutats per alimentar-se, mentres que les de ruscs urbans poden allunyar-se de la ciutat. En les mels urbanes, procedents de Barcelona i Viladecans, s’han identificat 89 TP, tant ornamentals com silvestres. L’ aparició dels TP Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. i Sophora sp., fan palesa la marcada influència de tàxons exòtics. D’altra banda, l’aparició d’un alt percentatge de tàxons arvenses indica que A. mellifera els visita, i reflecteix la importància de minimitzar l’ús d’ herbicides, i la d’adequar sòls amb aquest tipus de vegetació en ciutats. Referent als pròpolis, l’espectre pol·línic reflecteix la variabilitat de paisatges i vegetació de Catalunya. Es van analitzar 26 mostres que van permetre la determinació de 135 TP, dels quals els més freqüents van ser Asparagus sp., Brassicaceae T., Hedera helix, Quercus perennifoli y Rosmarinus officinalis. A més, les diferències observades en els pròpolis de Catalunya en funció del seu color i textura, podrien estar relacionades amb l’origen botànic de les resines procedents de Pinus sp., Quercus sp, Castanea sativa i Populus sp. Comparant les mostres de pròpolis i mel d’un mateix lloc, s’observa que la riquesa i la diversitat pol·línica és major en pròpolis que en mels i, encara que hi ha relació entre els seus espectres pol·línics, els tipus pol·línics difereixen en un 64,4%. Per això, l’estudi de l’espectre pol·línic de tots dos productes aporta una informació més precisa sobre la vegetació circumdant dels abellars, complementant i millorant la determinació de l’origen geogràfic de mels, sobretot, d’ aquelles amb una diversitat pol·línica molt baixa.Estudiar los productos de Apis mellifera derivados de recursos botánicos (miel, mielato, polen y propóleo), es útil para caracterizar y valorar los productos de la abeja de un territorio y para comprender las interacciones planta-polinizador. La melisopalinología tiene como objetivos la determinación geográfica y botánica de los productos apícolas, basándose en la presencia de tipos polínicos (TP). El primer objetivo de la presente tesis ha sido determinar qué plantas son útiles para A. mellifera en Catalunya, a través de una revisión bibliográfica y de observaciones in situ se ha elaborado una relación de 424 taxones útiles, de 114 familias Para el estudio melisopalinológico de las 51 mieles y 26 propóleos analizados en esta tesis se elaboró una palinoteca de referencia en base a los TP de los taxones de interés apícola de Catalunya. Como resultado del análisis melisopalinológico, se ha determinado el origen geográfico y botánico de mieles y propóleos, y se han identificado 156 TP de 74 familias. A través del análisis del espectro polínico de las mieles, se han tipificado distintos tipos de mieles, tanto multiflorales como monoflorales, de diferentes zonas geográficas y distintos años. Además, el análisis estadístico ha mostrado la existencia de diferencias significativas entre las mieles urbanas y el resto de mieles. En las mieles no urbanas, se han identificado 131 TP. Aunque los más frecuentes son autóctonos (Brassicaceae T., Coronilla T., Quercus perennifolio, Rubus T., Salix sp. y Ulex T.) la aparición de especies invasoras (como Ailanthus altissima) muestra su utilidad como recurso apícola, e indica que hay que tener en cuenta a este tipo de especies al establecer el origen geográfico y botánico de las mieles de un territorio. También, destacar la elevada presencia y porcentajes de TP como Cistus monspeliensis, Hedera helix, Rhamnus sp. y Salix sp., que podrían servir como indicadores para la tipificación geográfica de mieles de Catalunya. Por otro lado, se ve reflejada la importancia para A. mellifera de los ecosistemas de tipo matorral y herbáceo, así como que las abejas de la periferia de núcleos urbanos se adentran en las ciudades para alimentarse, mientras que las de colmenas urbanas pueden alejarse de la ciudad. En las mieles urbanas, de Barcelona y Viladecans, se han identificado 89 TP, tanto ornamentales como silvestres. La aparición de los TP Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. y Sophora sp., hacen patente la marcada influencia taxones exóticos. Por otro lado, la aparición de un alto porcentaje de taxones arvenses indica que A. mellifera los visita, y refleja la importancia de minimizar el uso de herbicidas, y la de adecuar suelos con este tipo de vegetación en ciudades. Referente a los propóleos, el espectro polínico refleja la variabilidad de paisajes y vegetación de Catalunya. Se analizaron 26 muestras que permitieron la determinación de 135 TP, de los cuales los más frecuentes fueron Asparagus sp., Brassicaceae T., Hedera helix, Quercus perennifolio y Rosmarinus officinalis. Además, las diferencias observadas en los propóleos de Catalunya en función de su color y textura, podrían estar relacionadas con el origen botánico de las resinas procedentes de Pinus sp., Quercus sp, Castanea sativa y Populus sp. Comparando las muestras de propóleo y miel de un mismo lugar, se observa que la riqueza y la diversidad polínica es mayor en propóleos que en mieles y, aunque existe relación entre sus espectros polínicos difieren en un 64.4%. Por ello, el estudio del espectro polínico de ambos productos aporta una información más precisa sobre la vegetación circundante de los colmenares, complementando y mejorando la determinación del origen geográfico de mieles, sobre todo, aquellas con una diversidad polínica muy baja.
The study of Apis mellifera products derived from botanical resources (honey, honeydew honey, corbicular pollen, and propolis) is useful to assess the quality of bee products in a territory and to better understand plant-pollinator interactions. The main objectives of Melissopalynology are the determination of the geographical and botanical origin of bee products, based on the presence of nectariferous and/or polliniferous pollen types (PT). The first objective of this thesis was to determine which plants are useful to A. mellifera in Catalonia, through a literature review as well as on-site observations has been obtained a list of 424 useful taxa from 114 families. For the melissopalynological study of the 51 honeys and 26 propolis analyzed in this thesis, a reference palinotheque was elaborated based on the list of the pollen types (PT) from the taxa with beekeeping interest in Catalonia. As a result of the melissopalynological analysis, the geographical and botanical origin of the honeys and propolis have been determined, and 156 pollen types of 74 families identified. Through the analysis of the pollen spectrum of honeys, different types of honey have been typified, both multifloral and monofloral, from different geographical areas and from different years. In addition, the statistical analysis has demonstrated the existence of significant differences between urban honey and other honey. In non-urban honeys 131 PT were identified. Although the most frequent are native (Brassicaceae T., Coronilla T., Quercus deciduous, Rubus T., Salix sp., and Ulex T.), the appearance of invasive species (such as Ailanthus altissima) shows it’s as apicultural resource, and indicates that this type of species must be taken into account when establishing the geographical and botanical origin of honeys from a given territory. Also, the high presence and percentages of PT such as Cistus monspeliensis, Hedera helix, Rhamnus sp. and Salix sp. could serve as indicators for the geographical classification of honey from Catalonia. On the other side, it has been reflected the importance for A. mellifera of shrubland and herbaceous ecosystems, as well as that honeybees located on the periphery of urban centers enter the cities to feed, and that bees from urban beehives can move outside the city. In the urban honeys from Barcelona and Viladecans, 89 PT were identified, both ornamental and wild. The presence of Cercis, Phoenix, Schinus, Agave, Ailanthus altissima, Eucalyptus sp. and Sophora sp. reveal the marked influence of exotic taxa. On the other hand, the appearance of a high percentage of PT of weed taxa indicates that A. mellifera visits them, and reflects the importance of minimizing the use of herbicides and of implementing soils with this type of vegetation in cities. Regarding propolis, the pollen spectrum reflects the variability of landscapes and vegetation in Catalonia. 26 samples were analyzed, and 135 PT determined, of which the most frequent being Asparagus sp., Brassicaceae T., Hedera helix, Quercus deciduous and Rosmarinus officinalis. Furthermore, the differences observed in the propolis of Catalonia, on the basis of their color and texture, could be related to the botanical origin of the resins from Pinus sp., Quercus sp, Castanea sativa, and Populus sp. Comparing the samples of propolis and honey from the same place, it was observed that the richness and diversity of pollen is greater in propolis than in honey and, although there is a relationship between their pollen spectra, the pollen types differ by 64.4%. Therefore, the study of the pollen spectrum of both products provides more precise information about the surrounding vegetation of the beehives, complementing and improving the determination of the geographical origin of honey, especially those with a very low pollen diversity.
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Landi, Lorrayne Albernaz Domingues Camilo. "Palinotaxonomia em espécies brasileiras do complexo Codonanthe-Codonanthopsis e gêneros relacionados /". Jaboticabal, 2017. http://hdl.handle.net/11449/151255.
Testo completoAbstract (sommario):
Orientador: Eduardo Custódio GasparinoCoorientador: Alain Chautems
Banca: Cynthia Fernandes Pinto da Luz
Banca: Claudia Barbieri Ferreira Mendonça
Resumo: Palinotaxonomia em Espécies Brasileiras do complexo Codonanthe- Codonanthopsis (Gesneriaceae) e gêneros relacionados - Será estudada a morfologia dos grãos de pólen de 25 espécies brasileiras dos gêneros Codonanthe (Mart.) Hanst., Codonanthopsis Mansf., Nematanthus Schrad. e Paradrymonia Hanst., distribuídas em sua maioria em dois biomas, Amazônia e Mata Atlântica. O objetivo deste trabalho é contribuir com a caracterização palinológica, em busca de dados morfológicos que possam melhor definir as espécies estudadas, auxiliando dessa forma, o melhor entendimento das relações de parentesco entre os gêneros e na compreensão da distinção florística entre os respectivos biomas. Os grãos de pólen foram acetolisados, medidos e fotografados sob microscopia de luz, microscopia eletrônica de varredura e transmissão. Os dados quantitativos receberam tratamento estatístico e descritivos, adequado ao tamanho das amostras e foram submetidos a uma análise multivariada identificando caracteres polínicos importantes na distinção das espécies. Os resultados obtidos com este estudo confirma a diversidade polínica para a Gesneriaceae, como já relatado na literatura. Os caracteres que mais contribuíram para distinção entre os gêneros, que auxiliarão trabalhos evolutivos futuros, foram a ornamentação dos grãos de pólen e as características de abertura. As espécies de Codonanthe e Codonanthopsis apresentam ornamentação predominantemente microrreticulada, diferente de Paradrymonia e Nematanthus com ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Palynotaxonomy in Brazilian species of Codonanthe-Codonanthopsis complex (Gesneriaceae) and related genera - The morphology of the pollen grains of 25 Brazilian species Codonanthe (Mart.) Hanst., Codonanthopsis Mansf., Nematanthus Schrad. and Paradrymonia Hanst., distributed mostly in two biomes, the Amazon rainforest and Atlantic Forest. The objective of this study is to contribute with the palynological characterization, in search of morphological data that can better define the studied species, a, thus helping, the better understanding of kinship relations between the genera and in the understanding of the floristic distinction between the respective biomes. The pollen grains were acetolysed, measured and photographed under light microscopy, scanning electron microscopy and transmission. The quantitative data were submitted to a multivariate analysis, identifying pollen characters that were important for the species classification. The results obtained with this study confirm the pollen diversity for the Gesneriaceae, as already reported in the literature. The characters that contributed the most to distinguish between the genera, which will help future evolutionary works, were the ornamentation of the pollen grains and the aperture characteristics. The species of Codonanthe and Codonanthopsis present predominantly microreticulate ornamentation, different from Paradrymonia and Nematanthus with pollen grains mostly reticulate. For Paradrymonia, there were no variations in the ornamentation of the apocolpium and mesocolpium of its pollen grains; in Nematanthus we can see a variation in the pattern of ornamentation between the apocolpium and mesocolpium regions (from microreticulate, reticulate to foveolate). Pollen grains with colpate aperture were described for Codonanthopsis, and for Paradrymonia pollen grains colp... (Complete abstract click electronic access below)
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Tebbutt, Scott James. "Pollen-specific gene expression". Thesis, University of East Anglia, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334705.
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Kitaoka, Traci Kimiko. "Bumble bee pollen foraging activation role of colony stores and pollen quality and odor /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1453656.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of California, San Diego, 2008.Title from first page of PDF file (viewed July 25, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 28-29).
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Németh, M. Barbara. "Pollen Performance and Seedling Vigor in Laboratory and Natural Populations of Clarkia Unguiculata (Onagraceae)". Miami University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=miami1117816212.
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Gessman, Daniel J. "Pollen Forecasting in Sarasota, Florida". Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6845.
Testo completoAbstract (sommario):
Current predictions of pollen levels rely strictly on historical Averages, regardless of environmental factors that might affect the timing of pollen release by different plants. For this thesis, the goal was to develop a statistical model that will accurately forecast pollen levels by correlating those daily counts to atmospheric and meteorological conditions. This project used ARIMA modeling on IBM’s SPSS Statistics 24 of daily pollen count information for multiple allergenic pollens in the Sarasota County, Florida area over a 11-year period. The pollen species in question for this project are oak and cypress trees, grass, and ragweed pollens; and Alternaria and Cladosporium mold spores. The total pollen counts for weeds, grass, trees, and overall total are also included in the 11 years of data. The atmospheric variables used to predict pollen levels are high temperature, low temperature, average temperature, precipitation, humidity, wind direction, and wind speed for daily observations over the 11-year period. Results for these models showed that maximum temperature, precipitation, humidity, and wind direction were the driving predictors behind the pollen counts in Sarasota, Florida. The analysis of the pollination periods also showed that there were phenological changes according to the specific species. The models and phenological changes are specific to the Sarasota, Florida area, and would serve as a framework for studying other pollination regions.
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Banks, Hannah. "Pollen structure in Caesalpinioid legumes". Thesis, Oxford Brookes University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401805.
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Lee, Christopher B. "Pollen-pistil interactions in nicotiana". Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6089.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 4, 2009) Vita. Includes bibliographical references.
Libri sul tema "Pollen"
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Noon, Jeff. Pollen. New York: Crown Publishers, 1996.
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Boucheron, Rose. Pollen. London: Piatkus, 1989.
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Geitmann, Anja, a cura di. Pollen and Pollen Tube Biology. New York, NY: Springer US, 2020. http://dx.doi.org/10.1007/978-1-0716-0672-8.
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FLORENCE, VANOLI. POLLEN DES NUITS - POLEN DE LA NOCHE. Vitoria-Gasteiz: ARTE ACTIVO EDICIONES, 2011.
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Mohapatra, Shyam S., e R. Bruce Knox, a cura di. Pollen Biotechnology. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4757-0235-4.
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Sofiev, Mikhail, e Karl-Christian Bergmann, a cura di. Allergenic Pollen. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-4881-1.
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Shivanna, K. R., e N. S. Rangaswamy. Pollen Biology. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77306-8.
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Moore, Peter D. Pollen analysis. 2a ed. Oxford: Blackwell Science, 1991.
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Moore, Peter D. Pollen analysis. 2a ed. Oxford: Blackwell Scientific, 1991.
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(Firm), Tender Buttons, a cura di. Pollen memory. New York: Tender Buttons, 2003.
Cerca il testo completoCapitoli di libri sul tema "Pollen"
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Jacobs, Joela. "Pollen". In Microbium, 99–112. Earth, Milky Way: punctum books, 2023. http://dx.doi.org/10.53288/0396.1.08.
Testo completoAbstract (sommario):
When you are inhaling pollen, your body has been penetrated by a little package of plant sperm. Pollen grains are multicellular organisms that contain male sex cells, and their job is to get this sperm to the egg to facilitate fertilization. For that, they hitch a ride on insects or trust their fate to wind, water, and any other moving means, including us. Yet most human-pollen encounters are only noticed when they result in an allergic reaction. Allergies have been on the rise, which is at least partly because pollen is too: Pollen counts have been going up in urban environments due to the tendency of city planners to plant male trees, which avoids problems with fruit falling on heads, cars, and sidewalks. Yet this also means that pollen is not absorbed by female trees and left roaming the streets to enter human noses instead. This self-made allergy problem demonstrates that we often seem to neglect what pollen is and does: As a miniscule sperm delivery mechanism, it is all about sex. Accordingly, pollen’s cultural history has predominantly been focused on attraction rather than allergic aversion, and because of that, pollen has shaped not only our understanding of plant fertility, but also human ideas about eroticism and sexuality, reproduction and desire.
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Ibrahim, Mohamed Ismail, Ali Al-Dousari e Abeer Hassan Al-Saleh. "Pollen in Dust". In Atlas of Fallen Dust in Kuwait, 177–96. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66977-5_7.
Testo completoAbstract (sommario):
Abstract Twenty-eight pairs of pollen and aeolian dust traps covering the State of Kuwait were used to obtain seasonal pollen counts of the most eight dominant families during 2009–2011 i.e. Chenopodiaceae, Poaceae (Gramineae), Cyperaceae, Leguminosae (Fabaceae), Cyperaceae, Brassicaceae, Malvaceae, Compositae, and Plantaginaceae. The sampling site locations were chosen to cover all the geomorphological sectors and native vegetation areas in Kuwait. Generally, pollen counts show us a remarkable distinction between the year 2009–2010 and 2010–2011, It is also evident that pollen counts (concentration) vary from season to season. Pollen counts over four seasons for two years (October 2009–August 2011) reveal the presence of two peaks in spring (April–May) and autumn (October–November). Map distribution of pollens in each of the dominant plant families in Kuwait is generated according to seasons showing higher and lower concentrations of dust pollen counts.
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Kellogg, Elizabeth A. "Pollen". In Flowering Plants. Monocots, 63–67. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-15332-2_6.
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Bährle-Rapp, Marina. "Pollen". In Springer Lexikon Kosmetik und Körperpflege, 435. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_8076.
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Wan, Samuel. "Pollen". In New Masters of Flash, 34–67. Berkeley, CA: Apress, 2001. http://dx.doi.org/10.1007/978-1-4302-5143-9_2.
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Bowman, J. L., J. Dawson, Z. A. Wilson, L. G. Briarty, B. J. Mullingan, S. Craig e A. Chaudhury. "Pollen". In Arabidopsis, 275–95. New York, NY: Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4612-2598-0_4.
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Prance, Ghillean T. "Pollen". In Humiriaceae, 15–16. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-82359-7_6.
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Cavalcanti, Taciana Barbosa. "Pollen". In Flora Neotropica, 51–53. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-65875-5_6.
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Burgos-Ellis, Helen. "Pollen". In Natural Things in Early Modern Worlds, 22–50. London: Routledge, 2023. http://dx.doi.org/10.4324/9781003351054-4.
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Chen, Tong, Xiaoqin Wu, Yanmei Chen, Nils Böhm, Jinxing Lin e Jozef Šamaj. "Pollen and Pollen Tube Proteomics". In Plant Proteomics, 270–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-72617-3_17.
Testo completoAtti di convegni sul tema "Pollen"
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Danhope-Smith, Stefanie, e Payaal Patel. "Pollen". In CHI '05 extended abstracts. New York, New York, USA: ACM Press, 2005. http://dx.doi.org/10.1145/1056808.1057103.
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Kawaguchi, Chihiro, Masateru Taniguchi, Makusu Tsutsui, Satoyuki Kawano e Tomoji Kawai. "Electrical Detection of Pollen Allergen Using Electrode-Embedded-Micro-Channel". In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-36035.
Testo completoAbstract (sommario):
Hay fever is a disease that approximately 20 percent of the world population develop. Providing appropriate treatment for this plant-specific pollen allergy requires a method to identify various types of pollen. Here we introduce a technique that can be used for direct detections of single biological macromolecules such as pollen. Our method is based on two-probe current measurements using a microfluidic-channel-embedded-electrode system. A fabrication procedure of the device is as follows. First, we formed two gold nanoelectrodes by standard electron beam lithography and lift-off processes. The interelectrode gap distance was designed to be 500 nm. We then deposited a SiO2 layer. After that, we fabricated Cr etching mask. Finally, we dry-etched the sample by reactive ion etching and obtained a microfluidic-channel-embedded-electrode structure. We flowed HEPES(2-[4-(2-Hydroxyethyl)-1-piperazinyl] ethanesulfonic acid) solution containing pollen of 500 nm size into the micro-channel and simultaneously measured current flowing through the two electrodes. Characteristic spike-like signals were observed; sharp rise of the current followed by a rather smooth decrease to the base current level. We exhibited control experiments in a HEPES solution wherein no pollen was added and observed only featureless current traces. We anticipate that the sharp current rise is associated with trapping of a single cedar pollen between the electrodes whereas the gradual current decrease represents the pollen detrapping. We propose the technique for identifying several kinds of pollens based on the height and the width of the current spikes.
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Jagtiani, Ashish, Jiang Zhe e Bi-min Zhang Newby. "Simultaneous Detection of Multiple Bioparticles With a High Throughput Resistive Pulse Sensor". In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-15565.
Testo completoAbstract (sommario):
We describe an all-electronic, label-free, resistive pulse sensor that utilizes multiple micropores for simultaneous detection and counting of multiple biological particles. Four particle samples were utilized for the sensor testing: 20μm and 40μm polymethacrylate (PM) particles, Juniper pollen and Eastern Cottonwood pollen. Experiments demonstrated that this sensor was able to differentiate and count multiple particle solutions simultaneously through its four micropores fabricated on polymer membranes. Thus the sensing throughput has been improved significantly. Furthermore, the experimental results also proved the feasibility of differentiating various pollens from PM microparticles with the multi-pore resistive pulse sensor, with no need for labeling of samples.
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Djubina, Nikola, Kristiana Jansone e Olga Sozinova. "Innovative methods for air micropollution research". In International Conference of Young Scientists on Meteorology, Hydrology and Environmental Monitoring. Ukrainian Hydrometeorological Institute, 2023. http://dx.doi.org/10.15407/icys-mhem.2023.020.
Testo completoAbstract (sommario):
Microscopic biological pollution, such as pollen, can have detrimental effects on human health, serving as a primary cause of respiratory allergies and pollinosis. Furthermore, pollen, as a prominent constituent of biological microscopic pollution, may contribute to the dispersion of industrial pollutants due to the accumulation of chemical elements on its surface. This study aims to evaluate the capacity of pollen to adhere to and transport particulate matter, including potential microplastics. The study encompasses a comprehensive approach, involving multiple aspects of pollen collection. Firstly, pollen samples were obtained directly from plants. Additionally, pollen was collected from various surfaces, representing different environmental contexts. Furthermore, specialized techniques were employed to capture pollen from airflow. Lastly, controlled laboratory conditions were established to simulate pollution of pollen samples. The collected pollen samples were then subjected to analysis using a scanning electron microscope to examine the composition of the pollen wall, detect different chemical elements, and identify the presence of nanometer-sized particles on the pollen surface. Through this investigation, two distinct types of pollen samples were differentiated: clean and polluted. The analysis of clean pollen samples revealed the presence of chemical elements, including oxygen (O), carbon (C), potassium (K), phosphorus (P), and calcium (Ca), on the surfaces of hazel (Corylus) and alder (Alnus) pollen. It should be noted that the concentration of these elements may vary depending on factors such as plant species and growth conditions. Moreover, hazel pollen (Corylus) exhibited the presence of chemical elements like lead (Pb), zinc (Zn), and tin (Sn), which can be attributed to environmental pollution. This abstract presents a preliminary overview of the study, with future research planned to expand upon these initial findings. Subsequent investigations will involve the inclusion of additional plant species and rigorous laboratory experiments to further elucidate the variations in pollen wall composition across different plants, while also considering the influence of diverse growth conditions and environmental factors.
5
Xue, Yingen. "Neonicotinoid residues in fresh corn pollen and proportion of corn pollen in bee-collected pollen during corn pollination". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.115318.
Testo completo
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Yuan, Fang, Yun-Quan Deng e Bao-Shan Wang. "The observation of pollen viability and pollen tube germination inLimonium bicolor". In International conference on Human Health and Medical Engineering. Southampton, UK: WIT Press, 2014. http://dx.doi.org/10.2495/hhme130841.
Testo completo
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Liang, Yuqing, Yuanmin Wang, Liubo Yang, Hongmei Wu e Xiangpei Wang. "GC--MS analysis of Japanese Banana Flower without pollen and Pollen". In International Conference on Advances in Energy, Environment and Chemical Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/aeece-15.2015.158.
Testo completo
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Heimann, U., J. Haus e D. Zuehlke. "OP3 - Fully Automated Pollen Analysis and Counting: The Pollen Monitor BAA500". In SENSOR+TEST Conferences 2009. AMA Service GmbH, Von-Münchhausen-Str. 49, 31515 Wunstorf, Germany, 2009. http://dx.doi.org/10.5162/opto09/op3.
Testo completo
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Musunuri, Naga, Ian Fischer, Pushpendra Singh, Daniel E. Bunker e Susan Pell. "Fluid Dynamics of Hydrophilous Pollination in Ruppia (Widgeon Grass)". In ASME 2016 Fluids Engineering Division Summer Meeting collocated with the ASME 2016 Heat Transfer Summer Conference and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/fedsm2016-7891.
Testo completoAbstract (sommario):
The aim of this work is to understand the physics underlying the mechanisms of two-dimensional aquatic pollen dispersal, known as hydrophily, that have evolved in several genera of aquatic plants, including Halodule, Halophila, Lepilaena, and Ruppia. We selected Ruppia maritima, which is native to salt and brackish waters circumglobally, for this study. We observed two mechanisms by which the pollen released from male inflorescences of Ruppia is adsorbed on a water surface: 1) inflorescences rise above the water surface and after they mature their pollen mass falls onto the surface as clumps and disperses as it comes in contact with the surface; 2) inflorescences remain below the surface and produce air bubbles which carry pollen mass to the surface where it disperses. In both cases dispersed pollen masses combined with others under the action of lateral capillary forces to form pollen rafts. The formation of porous pollen rafts increases the probability of pollination since the attractive capillary force on a pollen raft toward a stigma is much larger than on a single pollen grain. The presence of a trace amount of surfactant can disrupt the pollination process as the pollen is not captured or transported on the water surface.
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Салтанович, Татьяна, Людмила Анточ e А. Дончилэ. "Особенности мужского гаметофита томата в условиях вирусного патогенеза и водного дефицита". In VIIth International Scientific Conference “Genetics, Physiology and Plant Breeding”. Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2021. http://dx.doi.org/10.53040/gppb7.2021.25.
Testo completoAbstract (sommario):
On the example of F1 hybrid combinations and tomato varieties, the possibility of the assessing method for pollen selection on the responses of male gametophytes under conditions of viral pathogenesis and drought has been shown. It was found the action of factors on the pollen viability and on the rate of pollen tubes growth, leading to the manifestation of differential reactions. The viruses are the main sources of variability of the pollen functional traits, while the effect of water deficit and genotype are considerably weaker. Genotypes that combine the high viability of pollen with the ability to form longer pollen tubes under the complementary action of viruses and water deficit have been identified, suggesting the prospect of these genotypes using in further breeding studies.
Rapporti di organizzazioni sul tema "Pollen"
1
Law, Edward, Samuel Gan-Mor, Hazel Wetzstein e Dan Eisikowitch. Electrostatic Processes Underlying Natural and Mechanized Transfer of Pollen. United States Department of Agriculture, maggio 1998. http://dx.doi.org/10.32747/1998.7613035.bard.
Testo completoAbstract (sommario):
The project objective was to more fully understand how the motion of pollen grains may be controlled by electrostatic forces, and to develop a reliable mechanized pollination system based upon sound electrostatic and aerodynamic principles. Theoretical and experimental analyses and computer simulation methods which investigated electrostatic aspects of natural pollen transfer by insects found that: a) actively flying honeybees accumulate ~ 23 pC average charge (93 pC max.) which elevates their bodies to ~ 47 V likely by triboelectrification, inducing ~ 10 fC of opposite charge onto nearby pollen grains, and overcoming their typically 0.3-3.9 nN detachment force resulting in non-contact electrostatic pollen transfer across a 5 mm or greater air gap from anther-to-bee, thus providing a theoretical basis for earlier experimental observations and "buzz pollination" events; b) charge-relaxation characteristics measured for flower structural components (viz., 3 ns and 25 ns time constants, respectively, for the stigma-style vs. waxy petal surfaces) ensure them to be electrically appropriate targets for electrodeposition of charged pollen grains but not differing sufficiently to facilitate electrodynamic focusing onto the stigma; c) conventional electrostatic focusing beneficially concentrates pollen-deposition electric fields onto the pistill tip by 3-fold as compared to that onto underlying flower structures; and d) pollen viability is adequately maintained following exposure to particulate charging/management fields exceeding 2 MV/m. Laboratory- and field-scale processes/prototype machines for electrostatic application of pollen were successfully developed to dispense pollen in both a dry-powder phase and in a liquid-carried phase utilizing corona, triboelectric, and induction particulate-charging methods; pollen-charge levels attained (~ 1-10 mC/kg) provide pollen-deposition forces 10-, 77-, and 100-fold greater than gravity, respectively, for such charged pollen grains subjected to a 1 kV/cm electric field. Lab and field evaluations have documented charged vs. ukncharged pollen deposition to be significantly (a = 0.01-0.05) increased by 3.9-5.6 times. Orchard trials showed initial fruit set on branches individually treated with electrostatically applied pollen to typically increase up to ~ 2-fold vs. uncharged pollen applications; however, whole-tree applications have not significantly shown similar levels of benefit and corrective measures continue. Project results thus contribute important basic knowledge and applied electrostatics technology which will provide agriculture with alternative/supplemental mechanized pollination systems as tranditional pollen-transfer vectors are further endangered by natural and man-fade factors.
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Radev, Zheko. Sugars Composition of Bee-collected Pollen. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, dicembre 2021. http://dx.doi.org/10.7546/crabs.2021.11.03.
Testo completo
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Miller, Gad, e Jeffrey F. Harper. Pollen fertility and the role of ROS and Ca signaling in heat stress tolerance. United States Department of Agriculture, gennaio 2013. http://dx.doi.org/10.32747/2013.7598150.bard.
Testo completoAbstract (sommario):
The long-term goal of this research is to understand how pollen cope with stress, and identify genes that can be manipulated in crop plants to improve reproductive success during heat stress. The specific aims were to: 1) Compare heat stress dependent changes in gene expression between wild type pollen, and mutants in which pollen are heat sensitive (cngc16) or heat tolerant (apx2-1). 2) Compare cngc16 and apx2 mutants for differences in heat-stress triggered changes in ROS, cNMP, and Ca²⁺ transients. 3) Expand a mutant screen for pollen with increased or decreased thermo-tolerance. These aims were designed to provide novel and fundamental advances to our understanding of stress tolerance in pollen reproductive development, and enable research aimed at improving crop plants to be more productive under conditions of heat stress. Background: Each year crop yields are severely impacted by a variety of stress conditions, including heat, cold, drought, hypoxia, and salt. Reproductive development in flowering plants is highly sensitive to hot or cold temperatures, with even a single hot day or cold night sometimes being fatal to reproductive success. In many plants, pollen tube development and fertilization is often the weakest link. Current speculation about global climate change is that most agricultural regions will experience more extreme environmental fluctuations. With the human food supply largely dependent on seeds, it is critical that we consider ways to improve stress tolerance during fertilization. The heat stress response (HSR) has been intensively studied in vegetative tissues, but is poorly understood during reproductive development. A general paradigm is that HS is accompanied by increased production of reactive oxygen species (ROS) and induction of ROS-scavenging enzymes to protect cells from excess oxidative damage. The activation of the HSR has been linked to cytosolic Ca²⁺ signals, and transcriptional and translational responses, including the increased expression of heat shock proteins (HSPs) and antioxidative pathways. The focus of the proposed research was on two mutations, which have been discovered in a collaboration between the Harper and Miller labs, that either increase or decrease reproductive stress tolerance in a model plant, Arabidopsis thaliana (i.e., cngc16--cyclic nucleotide gated channel 16, apx2-1--ascorbate peroxidase 2,). Major conclusions, solutions, achievements. Using RNA-seq technology, the expression profiles of cngc16 and apx2 pollen grains were independently compared to wild type under favourable conditions and following HS. In comparison to a wild type HSR, there were 2,776 differences in the transcriptome response in cngc16 pollen, consistent with a model in which this heat-sensitive mutant fails to enact or maintain a normal wild-type HSR. In a comparison with apx2 pollen, there were 900 differences in the HSR. Some portion of these 900 differences might contribute to an improved HSR in apx2 pollen. Twenty-seven and 42 transcription factor changes, in cngc16 and apx2-1, respectively, were identified that could provide unique contributions to a pollen HSR. While we found that the functional HS-dependent reprogramming of the pollen transcriptome requires specific activity of CNGC16, we identified in apx2 specific activation of flavonol-biosynthesis pathway and auxin signalling that support a role in pollen thermotolerance. Results from this study have identified metabolic pathways and candidate genes of potential use in improving HS tolerance in pollen. Additionally, we developed new FACS-based methodology that can quantify the stress response for individual pollen in a high-throughput fashion. This technology is being adapted for biological screening of crop plant’s pollen to identify novel thermotolerance traits. Implications, both scientific and agricultural. This study has provided a reference data on the pollen HSR from a model plant, and supports a model that the HSR in pollen has many differences compared to vegetative cells. This provides an important foundation for understanding and improving the pollen HSR, and therefor contributes to the long-term goal of improving productivity in crop plants subjected to temperature stress conditions. A specific hypothesis that has emerged from this study is that pollen thermotolerance can be improved by increasing flavonol accumulation before or during a stress response. Efforts to test this hypothesis have been initiated, and if successful have the potential for application with major seed crops such as maize and rice.
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Lagera, Anjela J., Lloyd O. Balinado, John Rex Baldomero, Hannah Fae I. Rotairo, Nariza L. Tero, Mailyn S. Maghinay, Irma F. Baluyo et al. Varying Sugars and Sugar Concentrations Influence In Vitro Pollen Germination and Pollen Tube Growth of Cassia alata L. Journal of Young Investigators, giugno 2017. http://dx.doi.org/10.22186/jyi.33.1.42-45.
Testo completo
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Staiger, C. J. Identification of Actin-Binding Proteins from Maize Pollen. Office of Scientific and Technical Information (OSTI), gennaio 2004. http://dx.doi.org/10.2172/820708.
Testo completo
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Brooks, G. R., e A. Grenier. Late Holocene pollen stratigraphy of Lake Louise, Manitoba. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2001. http://dx.doi.org/10.4095/212115.
Testo completo
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Firon, Nurit, Prem Chourey, Etan Pressman, Allen Hartwell e Kenneth J. Boote. Molecular Identification and Characterization of Heat-Stress-Responsive Microgametogenesis Genes in Tomato and Sorghum - A Feasibility Study. United States Department of Agriculture, ottobre 2007. http://dx.doi.org/10.32747/2007.7591741.bard.
Testo completoAbstract (sommario):
Exposure to higher than optimal temperatures - heat-stress (HS) - is becoming increasingly common to all crop plants worldwide. Heat stress coinciding with microgametogenesis, especially during the post-meiotic phase that is marked by starch biosynthesis, is often associated with starch-deficient pollen and male sterility and ultimately, greatly reduced crop yields. The molecular basis for the high sensitivity of developing pollen grains, on one hand, and factors involved in pollen heat-tolerance, on the other, is poorly understood. The long-term goal of this project is to provide a better understanding of the genes that control pollen quality under heat-stress conditions. The specific objectives of this project were: (1) Determination of the threshold heat stress temperature(s) that affects tomato and sorghum pollen quality whether: a) Chronic mild heat stress conditions (CMHS), or b) Acute heat stress (AHS). (2) Isolation of heat-responsive, microgametogenesis-specific sequences. During our one-year feasibility project, we have accomplished the proposed objectives as follows: Objectrive 1: We have determined the threshold HS conditions in tomato and sorghum. This was essential for achieving the 2nd objective, since our accumulated experience (both Israeli and US labs) indicate that when temperature is raised too high above "threshold HS levels" it may cause massive death of the developing pollen grains. Above-threshold conditions have additional major disadvantages including the "noise" caused by induced expression of genes involved in cell death and masking of the differences between heatsensitive and heat-tolerant pollen grains. Two different types of HS conditions were determined: a) Season-long CMHS conditions: 32/26°C day/night temperatures confirmed in tomato and 36/26°C day maximum/night minimum temperatures in sorghum. b) Short-term AHS: In tomato, 2 hour exposure to 42-45°C (at 7 to 3 days before anthesis) followed by transfer to 28/22±2oC day/night temperatures until flower opening and pollen maturation, caused 50% reduced germinating pollen in the heat-sensitive 3017 cv.. In sorghum, 36/26°C day/night temperatures 10 to 5 days prior to panicle emergence, occurring at 35 days after sowing (DAS) in cv. DeKalb28E, produced starch-deficient and sterile pollen. Objective 2: We have established protocols for the high throughput transcriptomic approach, cDNA-AFLP, for identifying and isolating genes exhibiting differential expression in developing microspores exposed to either ambient or HS conditions and created a databank of HS-responsivemicrogametogenesis-expressed genes. A subset of differentially displayed Transcript-Derived Fragments (TDFs) that were cloned and sequenced (35 & 23 TDFs in tomato and sorghum, respectively) show close sequence similarities with metabolic genes, genes involved in regulation of carbohydrate metabolism, genes implicated in thermotolerance (heat shock proteins), genes involved in long chain fatty acids elongation, genes involved in proteolysis, in oxidation-reduction, vesicle-mediated transport, cell division and transcription factors. T-DNA-tagged Arabidopsis mutants for part of these genes were obtained to be used for their functional analysis. These studies are planned for a continuation project. Following functional analyses of these genes under HS – a valuable resource of genes, engaged in the HS-response of developing pollen grains, that could be modulated for the improvement of pollen quality under HS in both dicots and monocots and/or used to look for natural variability of such genes for selecting heat-tolerant germplasm - is expected.
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Eyal, Yoram, e Sheila McCormick. Molecular Mechanisms of Pollen-Pistil Interactions in Interspecific Crossing Barriers in the Tomato Family. United States Department of Agriculture, maggio 2000. http://dx.doi.org/10.32747/2000.7573076.bard.
Testo completoAbstract (sommario):
During the evolutionary process of speciation in plants, naturally occurring barriers to reproduction have developed that affect the transfer of genes within and between related species. These barriers can occur at several different levels beginning with pollination-barriers and ending with hybrid-breakdown. The interaction between pollen and pistils presents one of the major barriers to intra- and inter-specific crosses and is the focus of this research project. Our long-term goal in this research proposal was defined to resolve questions on recognition and communication during pollen-pistil interactions in the extended tomato family. In this context, this work was initiated and planned to study the potential involvement of tomato pollen-specific receptor-like kinases (RLK's) in the interaction between pollen and pistils. By special permission from BARD the objectives of this research were extended to include studies on pollen-pistil interactions and pollination barriers in horticultural crops with an emphasis on citrus. Functional characterization of 2 pollen-specific RLK's from tomato was carried out. The data shows that both encode functional kinases that were active as recombinant proteins. One of the kinases was shown to accumulate mainly after pollen germination and to be phosphorylated in-vitro in pollen membranes as well as in-vivo. The presence of style extract resulted in dephosphorylation of the RLK, although no species specificity was observed. This data implies a role for at least one RLK in pollination events following pollen germination. However, a transgenic plant analysis of the RLK's comprising overexpression, dominant-negative and anti-sense constructs failed to provide answers on their role in pollination. While genetic effects on some of the plants were observed in both the Israeli and American labs, no clear functional answers were obtained. An alternative approach to addressing function was pursued by screening for an artificial ligand for the receptor domain using a peptide phage display library. An enriched peptide sequence was obtained and will be used to design a peptide-ligand to be tested for its effect o pollen germination and tube growth. Self-incompatibility (SI) in citrus was studied on 3 varieties of pummelo. SI was observed using fluorescence microscopy in each of the 3 varieties and compatibility relations between varieties was determined. An initial screen for an S-RNase SI mechanism yielded only a cDNA homologous to the group of S-like RNases, suggesting that SI results from an as yet unknown mechanism. 2D gel electrophoresis was applied to compare pollen and style profiles of different compatibility groups. A "polymorphic" protein band from style extracts was observed, isolated and micro-sequenced. Degenerate primers designed based on the peptide sequence date will be used to isolate the relevant genes i order to study their potential involvement in SI. A study on SI in the apple cultivar Top red was initiated. SI was found, as previously shown, to be complete thus requiring a compatible pollinator variety. A new S-RNase allele was discovered fro Top red styles and was found to be highly homologous to pear S-RNases, suggesting that evolution of these genes pre-dated speciation into apples and pears but not to other Rosaceae species. The new allele provides molecular-genetic tools to determine potential pollinators for the variety Top red as well as a tool to break-down SI in this important variety.
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Chen, Ru, Yao Sun e Guoqi Sima. Comparative efficacy and tolerance of intralymphatic, subcutaneous and sublingual immunotherapy for pollen-induced allergic rhinitis: a network meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, gennaio 2022. http://dx.doi.org/10.37766/inplasy2022.1.0078.
Testo completoAbstract (sommario):
Review question / Objective: What is the effect of intralymphatic, subcutaneous and sublingual immunotherapy for pollen-induced allergic rhinitis. Condition being studied: Immunotherapy is the classic treatment for allergic rhinitis. Intralymphatic immunotherapy is a new type of treatment. Currently, no studies have compared subcutaneous, sublingual and intralymphatic sublingual immunotherapy. At present, there is no review to compare the efficacy of intralymphatic, subcutaneous and sublingual immunotherapy for pollen-induced allergic rhinitis.
10
Arpaia, Mary Lu, Sharoni Shafir, Thomas Davenport e Arnon Dag. Enhancement of avocado pollination and productivity - an interdisciplinary approach. United States Department of Agriculture, gennaio 2007. http://dx.doi.org/10.32747/2007.7695882.bard.
Testo completoAbstract (sommario):
The original objective was to determine the impact of temperature on floral behavior and pollen tube growth and humidity on the proportions of self-, close, and cross-pollinated avocado fruit on trees growing in humid, coastal and dry, inland CA climates. Because self-pollination was demonstrated to be the prevailing mode of pollination in Florida cultivars in warm humid conditions, it was appropriate to determine if similar rates of self-pollination occur in a dry Mediterranean climate present in California. The conclusions of the work were that despite limiting cool temperatures present in Ventura County, where the research was conducted, self-pollination within Stage 2 flowers is the dominant mode of pollination at both the humid and dry sites. Moreover, it was determined that pollen transfer is mediated by wind and bees have a negligible role in pollen transfer. Temperatures that are marginally warm enough to allow somewhat normal floral opening and closing behavior are still insufficient to provide pollen tube growth to the ovule before abscission of the flower. These results provide the basis for understanding why growers utilizing solid block avocado plantings achieve good yields without bees.