Search

Grana, a journal focused on palynology and aerobiology, has undergone significant changes with the appointment of a new Editor-in-Chief, David Cantrill. Cantrill expresses gratitude to the previous Editor-in-Chief, Professor Else Marie Friis, for her contributions and mentorship. The journal had faced challenges in the past, including the untimely passing of Professor Gamal El-Ghazaly and Professor Siewert Nilsson, which led to delays in refereeing and publication. However, under Friis' leadership, the journal was able to overcome these difficulties and expand its publication frequency. Cantrill plans to assess the composition of the Editorial team and discuss potential changes to the journal's scope. The goal is to continue publishing high-quality research papers that facilitate scientific communication. [Extracted from the article]

The present issue of GRANA is devoted to pollen morphology and diversity of the Gnetales in time and space. Three papers address fossil pollen and two papers concern pollen of the extant genus Ephedra. Together, the papers of the issue contribute new information relevant for the understanding of the fossil and evolutionary history of the Gnetales, pollination biology in the group and implications for ephedroid pollen as indicators of palaeoclimate. [ABSTRACT FROM AUTHOR]

Mycological monitoring of some workplaces (a paper mill, a fur mill, a shoe factory, a secondary school, a kindergarten, a hospital and two cafes) in Lithuania was carried out over a period of 5 years between 1993 and 1997. The aim of the study was to investigate the concentrations and species composition of airborne fungi in the different premises as one of the most important criteria for evaluating their sanitary state. A "Krotov 818" slit-to-agar single-stage impactor (cut-off 0.5 μm) was used for sampling of total propagules, the volume of the samples being 0.05 m[sup 3] at a flow rate of 0.025 m[sup 3]/min. It was found that there were considerable differences in the numbers of airborne fungal propagules between the different workplaces investigated as well as between different areas of the same workplace. The data showed that some fungal species were cosmopolitan. People working for a long time in places involving production processes with the same sort of natural material are at risk of catching a respiratory, allergic or sometimes even mycotic disease as a result of certain fungal species adapting themselves to the environment. Distinctive species were isolated from the fur mill: Aspergillus genus fungi were abundant in those shops with constant high temperature and humidity; Chrysosporium, Arthroderma, Microsporum, Trichophyton and Candida species genus were found in the fur cutting- assembling and sewing shops. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to study the influence of air temperature on the start of Quercus pollination in Córdoba (Andalusia, Spain). Sixteen years of pollen counts were used. The start date of the pollen season in this period varied between 26[sup th] February and 7[sup th] April. Chilling requirements and heat accumulation were taken into account although no significant correlation between chilling hours and the start date was observed. Five different predictive methods based on heat accumulation were compared in this paper: 1) Number of days over a threshold; 2) Heat Units (accumulated daily mean temperature after deducting a base temperature); 3) Growing Degrees Days (Snyder 1988), as a measure of physiological growing time; 4) Accumulated maximum temperatures; and 5) Mean maximum temperature. Results indicated that the optimum base temperature for heat accumulation was 11 C[sup o]. This threshold was used in the first three methods mentioned above. Good statistical results were obtained with the five methods, yielding high levels of explanation (p~99%). Nevertheless, the most accurate method appeared to be the Growing Degree Days (GDD[sup o]) method, which indicated that a mean of 127.3 GDD[sup o] must be accumulated from the end of the chilling period up to the beginning of the Quercus pollen season in Córdoba (South West Spain). Results were tested for predicting start dates in 1999 and 2000. The predicted dates were only one day after the actual dates. [ABSTRACT FROM AUTHOR]

This paper presents the course of the pollen season of selected allergenic taxa (Rumex spp., Plantago spp., Urtica spp. and Chenopodiaceae) in two towns with different degrees of urbanisation (urban, the city Szczecin, and rural, the village Gudowo in Western Pomerania, northwest Poland). The study was conducted in the years 2012–2014 with the volumetric method. The pollen of allergenic herbaceous plants was present in the air from early May until the end of September. From among the taxa studied, the genusRumexis characterised by the longest pollination period, while the genusUrticaby the shortest. The highest percentage contribution of pollen grains to the total pollen count in the air reaching over 90% is from nettle. The pollen seasons determined for the majority of taxa are longer in the city, however the mean pollen grain counts in the air are higher for the rural area. [ABSTRACT FROM AUTHOR]

The uppermost Eocene Florissant Formation, Rocky Mountains, Colorado, has yielded numerous insect, vertebrate and plant fossils. Three previous comprehensive palynological studies investigated sections of lacustrine deposits of the Florissant Formation and documented the response of plant communities to volcanic eruptive phases but overall found little change in plant composition throughout the investigated sections. These studies reported up to 150 pollen and spore phenotypes. In the present paper, we used a taxonomic approach to the investigation of dispersed pollen and spores of the Florissant Formation. Sediment samples from the shale units containing macrofossils were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The general picture of the palynoflora is in agreement with previous studies. However, the combined LM and SEM investigation provides important complementary information to previous LM studies. While a fairly large amount of previous pollen determinations could be confirmed, the purported taxonomic affinities of several pollen phenotypes need to be revised. For example, pollen referred to asPodocarpusorPodocarpiditessp. belongs to the PinaceaeCathaya, Malus/Pyrusactually belongs to Dryadoideae, pollen of the form genusBoehlensipollisreferred to as Proteaceae/Sapindaceae/Elaeagnaceae orCardiospermumbelongs to Sapindaceae but not toCardiospermum, and pollen ofPersicarioipollissp. B with previously assumed affinities to Polygonaceae actually belongs to Thymelaeaceae.Pandaniiditesand one type ofMalvacipolliscannot be linked with Pandanaceae and Malvaceae. A few taxa are new records for Florissant (Ebenaceae:Diospyros; Mernispermaceae; Trochodendraceae:Tetracentron). In general, SEM investigations complement the LM palynological studies and improve the identification of dispersed pollen and spores and enable integration of data from dispersed fossil pollen into a wide range of comparative morphological, taxonomic, evolutionary, biogeographic and phylogenetic studies. [ABSTRACT FROM AUTHOR]

This paper is part of an investigation dedicated to indoor pollen from a forensic point of view. Previous studies documented the ‘natural’ pollen content of a flat and how it was ‘artificially’ altered by ornamental plants. The present study investigated if this ‘artificial pollen trace’ can be transferred to shoes. Brand new sneakers were worn in the flat and afterwards examined for pollen on their soles. The results showed that the shoes gathered pollen and that some pollen types correlated to those found in the flat. Afterwards, some of these shoes were worn while walking through the city for approximately 1.8 km. On these shoes, flat pollen was also detectable, but in low abundances. This study shows that, from a palynological point of view, shoes are worth a look at when a crime is investigated. Uncommon pollen grains on shoes can point to an indoor location with the corresponding ornamental plants. [ABSTRACT FROM AUTHOR]

The present paper analyses the pollen deposition pattern in a swampy area of tropical mixed deciduous forest at the Baikunthpur Forest Range in the Koriya District of Chhattisgarh, India, based on the palynological investigation of surface samples. The palynological assemblages revealed the dominance of non-arboreal pollen taxa (NAPs: herbs) over the arboreal pollen taxa (APs: trees and shrubs). Among the arboreal taxa, trees constitute on average 41.92% of the pollen in the total pollen rain, whereas the average contribution of shrubs is only 2.19%. Among the herbaceous taxa, Poaceae (grasses) has a relatively high frequency (average 38.20%). The NAPs, on the whole, constitute on average 53.51% of the pollen in the total pollen rain. Cerealia, Chenopodiaceae/Amaranthaceae, Caryophyllaceae, Brassicaceae,ArtemisiaandAlternantherareflect the agrarian activities in the study area. Cyperaceae and other marshy taxa represent boggy places around the sampling site andTypha,Lemna,PotamogetonandNymphoidesthe aquatic vegetation.Pinus,Cedrus,PiceaandAlnusoccur in low frequencies and are exclusively wind transported from the Himalayas. Trilete fern spores and lycopods are indicative of humid climatic condition. [ABSTRACT FROM AUTHOR]

The Havana aeromycobiota diversity was studied from November 2010 to October 2011 using two complementary volumetric methods. A total of 35 fungal genera were characterised, 26 of them were recognised only by non-viable methods, six with viable methodology and the other three with both sampling methods. Furthermore, 47 species were identified by cultivation and the spores collected with the non-viable methodology. These could not be included in a specific genus, and thus, were categorised into five fungal types. In general, the main, spread worldwide, mitosporic fungi also predominated the Havana atmosphere. The predominant species wereCladosporium cladosporioides,Aspergillus flavusandPenicillium citrinum. Moreover, several Zygomycetes (Syncephalastrum racemosum,Rhizopus stoloniferandRhizopus oryzae), Ascomycetes (Chaetomium globosum) and Basidiomycetes such asCoprinusorGanodermawere isolated. In the present paper, the review of the airborne fungi conducted in previous studies in Cuba was completed by the detection of two new genera and the first isolation of ten new records in the Cuban atmosphere. Most of the fungi detected showed a diurnal pattern with high spore peak at 11.00–12.00. [ABSTRACT FROM PUBLISHER]

An advanced protocol to prepare single extant and fossil pollen grains for transmission electron microscopy (TEM) analysis allows for the fast recovery of data on the ultrastructure of pollen/spores. The protocol is easy to apply and less time consuming than previous methods. The 'loss' of pollen grains and pollen that is 'difficult to locate' within the embedding material is avoided, and each single pollen grain can be prepared successfully for TEM analysis. This preparation method is meant as an addition to the single-grain method using combined light and scanning electron microscopy to investigate dispersed fossil pollen grains developed by Dr Reinhard Zetter in the late 1980s. [ABSTRACT FROM AUTHOR]

Cladosporium spores are ubiquitous in the air and are included in the fungal contaminants that define environmental quality. This paper provides an updated review of their concentration in the Iberian Peninsula, based on data from 12 sampling stations collected using a common non-viable volumetric sampling method and the same subsequent data-treatment techniques. The database comprised 84 annual periods, covering the period 1993–2009. Mean annual total spore concentrations for each station, calculated as the sum of daily concentrations, ranged from 54 459 in Cartagena to 933 485 in Sevilla; other sampling stations recorded annual total spores between 93 052 (Porto) and 579 953 (Mérida). Analysis of annual spore-distribution patterns revealed either one or two peaks (spring and fall) depending on the location and prevailing climate of the area where the sampling stations have been placed. For all stations, average temperature was the meteorological parameter displaying the strongest positive correlation with airborne spore concentrations. [ABSTRACT FROM AUTHOR]

Pollen morphology of Violaceae, a family of c. 825–900 species, has been little studied to date, with the exception of Viola. In this paper, we present the results of a survey of the pollen of representative species of 16 of the 23 genera of Violaceae, examined using light microscopy, scanning electron microscopy and selectively transmission electron microscopy. Pollen grains are isopolar monads with a mean polar diameter of 30.2 μm and a mean equatorial diameter of 34.1 μm. Unusually, two size classes were found in pollen of Fusispermum. The shape of Violaceae pollen is mostly suboblate or oblate spheroidal with an obtuse convex triangular amb. The apertures are tricolporate with the exception of Paypayrola where the pollen observed was dicolporate, and the endoapertures are mostly lalongate pores. The pollen surface is usually perforate and granular. The exine is tectate perforate and columellate, usually with thickened endexine at the apertures. Pollen descriptions are provided for 21 taxa representing most of the lineages in the phylogenetic tree produced by Tokuoka in 2008 using both plastid and nuclear genes. Pollen characters were optimised on this phylogeny using parsimony and our results indicate the high potential utility of pollen characters in the systematics of Violaceae. [ABSTRACT FROM PUBLISHER]

Leptosphaeria maculans and L. biglobosa are fungal pathogens able to cause allergic reactions in humans and infect plants of Brassica species. The rate of their development and subsequent spore release depend on weather conditions. The aim of this paper was to pinpoint the exact meteorological conditions triggering the release of L. maculans and L. biglobosa ascospores in central and eastern Poland. Multiple regressions indicated that the frequency and amount of rainfall over short periods were important in mediating spore release. The first ascospore event depended mainly on the number of rainy days during the first 10 days of July and the cumulative precipitation during July and September. The most important variables for maximum spore release were cumulative rainfall in the beginning of July and the end of September, as well as the number of days with precipitation events in the first 10 days of August. The results highlighted for the first time the importance of the days preceding the collection of oilseed rape plants from the field. Higher moisture content of senescing but still living stems play a crucial role in the early start of the ascospore season and the maximum release of ascospores. This was not yet considered to date. [ABSTRACT FROM PUBLISHER]

In this paper, we present advances in studies of Compositae pollen morphology made over the past two years, focusing on the presentation of novel pollen morphological data, the potential systematic implications for presently unplaced taxa, and a bibliography of the literature. The pollen of Allittia, Castroviejoa, Lorandersonia, Pembertonia and Rhetinocarpha was found to be typical of their taxonomic placements in Astereae and Gnaphalieae, showing a helianthoid pollen type. That of Berylsimpsonia is also congruent with its current taxonomic position in Mutisieae, corresponding to an anthemoid type with an infratectum comprising two layers of robust columellae, separated by a spongy internal tectum. The pollen of Cavea, at present incertae sedis, was found to be highly distinctive with prominent, peg-like spines. The palynological data suggest affinity to Mutisieae or Vernonieae, and indicate that palynology continues to play a useful role in the systematic study of unplaced taxa. The bibliography of 172 references indicates the high level of research activity currently taking place in Compositae pollen morphology; we highlight some aspects of the taxonomic distribution of this research. [ABSTRACT FROM PUBLISHER]

The palynoflora from the Lavanttal Basin is characterised by a diverse spectrum of conifers. Their pollen is mostly well preserved allowing for high taxonomic resolution. Most coniferous taxa belong to the Pinaceae (Abies, Cathaya, Cedrus, Keteleeria, Larix, Picea, Pinus and Tsuga) and the Cupressaceae (Cryptomeria, Glyptostrobus and Sequoia), but pollen of Sciadopityaceae (Sciadopitys) is also occuring. The presence of these conifer taxa supports previous suggestions based on sedimentological and palynological observations that the sediments of the Lavanttal Basin accumulated in a lowland/wetland environment. Many of the taxa described in this paper had a wide, mostly Northern Hemispheric distribution, occupying swamps, river plains, deltas, hummocks and also better drained habitats located near to the main areas of sedimentation during most of the Cenozoic. Modern relatives of most of the fossil taxa prefer ample precipitation, suggesting that during the Middle Miocene (Sarmatian), the Lavanttal area received plenty of rainfall; there is no indication of a seasonal climate with a drought period. In general, the conifer taxa identified here are suggestive of a warm-temperate climate. [ABSTRACT FROM PUBLISHER]

This paper reports the pollen sources selected by Apis mellifera in the area northwest of Santa Cruz (Argentina). It evaluates the relative biomass contribution and the protein content of the collected taxa. During the apicultural period (September 2008-March 2009) pollen loads from three colonies were collected every fortnight using pollen traps. Forty-two pollen types were found in the samples, from which 15 taxa had a biomass contribution over 1% of the total pollen crop. The main pollen sources were Brassicaceae, Taraxacum officinale, Convolvulus arvensis, Rosaceae, Salix spp. and Schinus marchandii (Anacardiaceae). Of the total pollen sources identified, 15 are new records for the bee pollen flora of Argentina and 13 are native plants of South America. The contribution of native flora occurred mainly in spring. Schinus marchandii, Mulguraea-Junellia type (Verbenaceae), Adesmia spp. (Fabaceae), Sysirinchium spp. (Iridaceae), Acaena spp. (Rosaceae), Astereae and Senecio spp. (Asteraceae) were the indigenous pollen types with the highest biomass contribution. Protein content of most collected pollen types was variable (between 13.25% and 24.43%). [ABSTRACT FROM AUTHOR]

The extensive pollen morphological diversity of the Cichorieae has been widely demonstrated, and previous studies have shown that in some cases pollen characters can contribute to our understanding of inter-generic relationships. This paper extends the range of genera for which pollen morphological information is available in two predominantly Old World sub-tribes, Crepidinae and Lactucinae. All the genera discussed were found to produce pollen belonging to previously described types. However, the inclusion of certain, previously under studied Asian genera and species, especially those from China, provides useful new information about the extent of pollen morphological diversity within and between genera in these subtribes, and may contribute to a better understanding of the systematics of these groups. [ABSTRACT FROM AUTHOR]

Continental-scale modern pollen-climate data repositories are a primary data source for palaeoclimate reconstructions. However, these repositories can contain artefacts, such as records from different depositional environments and replicate records, that can influence the observed pollen-climate relationships as well as the palaeoclimate reconstructions derived from these relationships. Because the depositional environment determines the relative strength of the local and regional pollen signals, combining data from different depositional environments results in pollen abundances that can be influenced by the local pollen signal. Replicate records in pollen-climate datasets can skew pollen-climate relationships by causing an overweighting of pollen abundances in a climate space. In this paper, we address the issues related to these artefacts as we define the methods used to create a research dataset from the North American Modern Pollen Database (NAMPD) (Whitmore et al., 2005). The research dataset we present consists of 2 613 records in eastern North America, of which 70.9% are lacustrine sites. The research dataset encompasses the majority of the temperature and Summer precipitation ranges of the NAMPD's climatic range, and 40% of its Winter precipitation range. We present our analyses of the research dataset and demonstrate that it improves upon regional pollen-climate relationship modelling of eastern North American taxa. [ABSTRACT FROM AUTHOR]

Pollen morphology is widely used in taxonomic treatments of tribe Vernonieae, and differences in exine structure and aperture form have been described for many species within the genera comprising the tribe. However, in recent years a number of new species have been described and, in the present paper, we describe in detail the pollen of 24 species of the tribe which are either endemic or uncommon to certain regions of Argentina or of Paraguay. The pollen of these species are radially symmetrical and more or less spheroidal, 3-colporate or, in one species, 3-porate; the exine may be tectate or semitectate and microperforate, with echinate lophae or, in the 3-porate example, psilate lophae. Using a range of characteristics related to size, shape, wall thickness, apertures and tectum surface morphology, five of the six pollen types previously described for tribe Vernonieae, and a subtype, are recognized. Our results support the usefulness of pollen morphology in helping to determine the taxonomic position of species within tribe Vernonieae. [ABSTRACT FROM AUTHOR]

Subfossil pollen from two co-existing Betula species in Iceland, B. nana and B. pubescens, is frequently found in sediments and peat. Interpretation of the findings often depends on the ability to differentiate between the two species according to pollen size and structure. Fresh pollen samples were prepared from 70 individual trees/shrubs which had been identified to species by chromosome number. Grain diameters and pore depths were measured and ratios of grain diameter to pore depth (D/P ratios) were calculated. The mean grain diameters of pollen from diploid B. nana and tetraploid B. pubescens were 20.42 and 24.20 µm, whereas mean pore depths were 2.20 and 2.81 µm respectively. Mean D/P ratios were therefore 9.55 for B. nana and 8.85 for B. pubescens. The difference between species was statistically significant for all three pollen parameters. Grain diameter appeared to be the most useful parameter, as only about 20% of the samples were in the overlapping region of the species distributions. Pollen size (grain diameter) was also positively correlated to tree morphology, which was evaluated using species-specific botanical characters. Pollen samples from different locations/populations in Iceland varied slightly in mean size and ratio. The size difference between pollen of B. nana and B. pubescens in this study is less than other papers have reported, which may be due to the effect of introgressive hybridisation between the two birch species in Iceland. [ABSTRACT FROM AUTHOR]

Pollen variations involving the number and position of the apertures are relatively frequent in certain members of Gentianaceae. In this paper the high incidence of pollen variation in Centaurium pulchellum (Sw.) Druce is described. Two other species of Centaurium: C. ameghinoi (Speg.) Druce and C. cachanlahuen (Molina) B. L. Rob were also examined. These two species have 3-colporate or, less frequently, 4-colporate pollen grains, which are the two basic aperture arrangements. However, there are also a variable proportion of atypical grains. Apart from typical 3-zonacolporate grains, C. ameghinoi sometimes has 3-syncolpate or parasyncolpate pollen, while C. cachanlahuen occasionally has 4-colporate grains with short colpi that converge in pairs. C. pulchellum also has 3 or 4-colporate grains, but a high proportion of the pollen grains show a range of different aperture patterns. A total of 13 aperture configurations, including the typical 3-colporate and 4-colporate types, were recorded. The proportion of the different pollen types varied widely between and within individuals. However, the production of atypical grains does not seem to have any notable effect on pollen viability within the species. It is suggested that the wide variation in aperture pattern observed in C. pulchellum may be partially induced by environmental factors. [ABSTRACT FROM AUTHOR]

This paper discusses a subjectively defined system of air mass types, the 13 Péczely's large-scale weather situations over the Carpathian Basin in relation to the detected airborne pollen grain concentrations. Based on the ECMWF (European Centre for Medium-Range Weather Forecasts) sea-level pressure data set, daily sea-level pressure fields analyzed at 00:00 UTC were prepared for each Péczely's weather types in order to relate the sea-level pressure patterns with the average pollen levels in Szeged. The data basis for this study comprises daily values of 12 meteorological parameters and daily average pollen concentrations for 24 species in a 5-year period (1997-2001). It was found that Péczely's anticyclonic ridge types 2 and 11 as well as cyclonic types 4 and 7 are favourable for pollen production and dispersal unlike the cyclonic types 3 and 13. Hence, the Péczely's large-scale weather situations cannot alone be considered as an overall system in predicting pollen concentrations. [ABSTRACT FROM AUTHOR]

Establishing a modern pollen analogue for remote, high-deposition environments (e.g. ice caps) presents a unique problem that is difficult to address with current technology. Collecting modern pollen with traditional Tauber traps in these locations (at sub-annual resolution) is nearly impossible due to the time and costs involved in frequent, long-distance or remote travel. Presented in this paper is an automated, dry-deposition Tauber trap with the ability to open and close on a timer, which allows for pollen collection at programmable intervals. This new trap (along with three traditional Tauber traps) was field tested in the summer of 2005 at the University of Colorado's Niwot Ridge Long-Term Ecological Research Station (LTER) located in the Front Range of the Colorado Rockies. During the research, one of the traditional traps became damaged and was subsequently discarded from the study. Significant variability in pollen concentrations and percentages was found in the remaining traps. Statistical tests revealed that the pollen assemblage collected in the automated trap was statistically no different to the pollen collected in the traditional Tauber traps. Field testing in a cold, high-wind environment also revealed the weaknesses of acrylic as a trap material, and identified several improvements that could be made to the overall design. Further testing aside, this modified, automated Tauber trap now permits modern pollen rain studies at higher resolutions in more remote locations. [ABSTRACT FROM AUTHOR]

Although exposure to airborne pollen grains and fungal spores has been implicated as a causative factor for acute exacerbation of asthma, the few epidemiologic studies that have attempted to evaluate the relationship between these bioaerosols and asthma have used only total counts (ignoring the relative importance of different taxa) or a few predominant pollen or spore types (ignoring less abundant but potentially relevant groups). This paper reports the development of hypothesis-driven exposure metrics (based on known aeroallergen associations with allergic asthma and other hypersensitivity diseases, pollen allergen cross-reactivity, and the presence of local sources in the city of Fresno, California, USA) for a 3.5 year epidemiologic study of childhood asthma. Outdoor regional and neighborhood concentrations of pollen and spores were measured using Hirst-type, 7-day samplers. Indoor and outdoor residential concentrations were measured at 84 selected homes with similar 24-hour slit impactors. All pollen and spore concentrations were recorded in 2-hour intervals to assist in understanding diurnal fluctuations in aeroallergen concentrations, identify exposures during the time periods that children are outdoors, and study interaction between aeroallergens and other air contaminants, which were the primary focus of the study. The 124 pollen taxa that were observed were reduced to 15 categories and the 66 fungal and algal taxa were reduced to five categories that will be used in microenvironmental models to generate individual daily exposure estimates for each of the 315 children. These new exposure metrics will allow examination of health effects for taxa traditionally associated with allergy and those with locally elevated concentrations in combination with exposures to other indoor and outdoor air contaminants. [ABSTRACT FROM AUTHOR]

In the anthers of flowering plants, gymnosperms, and seed ferns, tiny (±1 µm) granules might occur on the radial and innermost tangential wall of secretory tapetum cells. These sporopollenin granules develop simultaneously with the pollen exine and are called orbicules or Ubisch bodies. The present paper focuses on two quite different topics associated with orbicules. The morphological and ultrastructural diversity of orbicules in the order Gentianales is summarized, and it is demonstrated that orbicules are a plesiomorphic feature in the order. Furthermore, orbicule characters seemed to be correlated with evolutionary trends in pollen dispersal unit and tapetum type features. In the second part, we report on our investigation of Corylus avellana L. (Hazel) pollen, using immunogold electron microscopy to gain an insight into the possible role that orbicules may play as a vector of pollen allergens. During the pollen season orbicules are dispersed into the atmosphere along with Hazel pollen grains. The localisation of homologues of the new birch pollen allergen Bet v 7 was studied at the subcellular level in Hazel anthers. The results of this study indicate that orbicules and pollen of Hazel might act as very effective vectors for homologues of Bet v 7 and that debris of Hazel anthers represent vectors of allergens after the pollen season. [ABSTRACT FROM AUTHOR]

The Burseraceae are a medium-sized family in which 18 genera are currently recognised. They are the subject of a long-term project to describe the pollen morphology from light, scanning electron and transmission electron microscopy. The pollen morphology of tribe Protieae has been published, as well as an account of the pollen of the African taxa in the family. Pollen data for the other two tribes, Bursereae and Canarieae, are more or less complete. The pollen of all the genera have been examined, with the exception of the recently described Pseudodacryodes Pierlot for which, currently, there is no pollen material available. This paper summarises the results. There is considerable variation in exine and aperture features between, and occasionally within, the genera and 14 major pollen types are defined, including two previously undescribed types: ‘ Canarium oleiferum ’ and ‘ Canarium gracile ’. The distribution of pollen characteristics throughout the family is compared with previously published tribal and subtribal groupings, as well as with current ideas of generic relationships from molecular analyses. Comparisons show notable congruence of pollen data with molecular data. To some extent pollen morphology is different for each of the subtribes. Nevertheless, there are some notable exceptions, for example, the pollen of Garuga and Boswellia are remarkably similar, although Garuga has been included, somewhat tenuously, in tribe Protieae, and Boswellia is included in tribe Bursereae, subtribe Boswelliinae. In a recent molecular tree Garuga and Boswellia appear to be closely related, and this supports the conclusion, based on several macromorphological characters as well as pollen, that Garuga should be transferred to tribe Bursereae. [ABSTRACT FROM AUTHOR]

Qinghai‐Tibetan Plateau is one of the most sensitive areas to climate change of the earth, owing to its unique topographic features and ecosystem. Soil pollen analysis is an important component of palaeo‐ecological research, while pollen preservation and the relationship between pollen and vegetation can influence the correct interpretation of fossil pollen spectra. In this paper, 36 pollen samples, which come from four meadows and two forest soil pollen profiles, have been analyzed to determine relationships between pollen and vegetation and pollen preservation on the northeastern Qinghai‐Tibetan Plateau. The relationship between pollen and vegetation shows that the surface pollen assemblages can represent regional vegetation characteristics moderately, while Betula and Populus pollen is absent in the soil surface for Betula and Populus mixed forest. Artemisia , Chenopodiaceae, Ephedra, Pinus, Hippophae etc. are over‐represented pollen taxa, Leguminosae, Ranunculaceae, Rosaceae, Gramineae etc. are under‐represented pollen taxa. The study of pollen preservation indicates that pollen concentrations decrease with the increase of soil depths, more pollen taxa are present in surface soils than in deep levels, and more than 75% pollen grains will be lost from the surface soils to deep levels. Pollen sorting preservation function should be noticed. Artemisia and Chenopodiaceae can be preserved well and have higher pollen percentages in deeper levels. Cyperaceae and Populus are preserved worse, Populus pollen is absent and Cyperaceae has higher pollen percentages in the surface soil than in the deep levels. The high soil pH values are the most destructive factors for pollen preservation on the northeastern Qinghai‐Tibetan Plateau. Pollen concentrations decrease sharply when the soil pH values are over 7.6. Downward leaching of pollen is unimportant in this study. [ABSTRACT FROM AUTHOR]

The use of meteorological autocorrelation variables and pollen concentrations from previous days, coupled with classification of meteorological data according to multivariate analysis techniques, is shown to improve the predictive power of multiple regression models for daily pollen forecasts. This paper presents an investigation of the meteorological and autocorrelation variables which influence pollen counts in Cartagena, from 1995 to 1999, as a basis for the development of predictive models. The analysis of total pollen concentrations, and especially Chenopodiaceae-Amaranthaceae, was determined. Initially, forecasting models for total pollen counts were developed, using data from 1995 to 1998, and autocorrelation and meteorological variables. Secondly, predictive models were developed for different meteorological situations, which improved the results by decreasing the number of predictive parameters. Finally, data from 1999 were used to validate the predictive models. [ABSTRACT FROM AUTHOR]

Pollen is significant from a human health perspective because it has been known to trigger allergic respiratory disease such as asthma and hay fever. The presence of pollen in the atmosphere has been related to meteorological parameters in past studies, but this has not been done previously in Sydney, Australia. This paper reports the results of a study on Poaceae, Plantaginaceae, Casuarinaceae, and total pollen in Sydney. Pollen concentration data for the period 19 August 1992 to 31 December 1995 was examined with meteorological data for the same period. The daily pollen concentration was compared to the meteorological data for the same day and for up to three days previously. The analysis methods were Spearman's rank correlation and multiple regression. Poaceae, Plantaginaceae, and total pollen appear to be positively correlated with temperature, dew point temperature, and wind speed, and negatively correlated with air pressure. Casuarinaceae pollen is also related to these meteorological parameters, but the sign of the correlations is the opposite. There is potential for the results of this study to be used by public health authorities in the prediction of pollen concentrations in Sydney. [ABSTRACT FROM AUTHOR]

Airborne biological agents have become prominent safety and health issues in agriculture, biotechnology, industrial settings, and the indoor environment. Each of these environments presents unique exposure concerns due to the nature of the encountered biological agent, the microbial concentrations, the modes of exposure, and the susceptibility of the exposed population. Acceptable levels of airborne microorganisms have not been established and the sampling methods and analytical techniques employed to assess airborne biocontaminants are varied and non-standardized. This paper reviews and compares the different air sampling methods for biological agents and classical analytical methods (i.e., culture and microscopy), analysis for specific microorganism constituents (i.e., ergosterol, muramic acid, glucans, allergens, mycotoxins, endotoxins) and molecular methods (i.e., polymerase chain reactions). Each of the described methods has distinct advantages and disadvantages. Selection of sampling and analytical methods depends upon the nature of the information that is sought; there is no one ideal sampling or analytical method. Combinations of sampling and analytical methods can provide a wide range of data that can be effectively tailored to many different environmental settings. [ABSTRACT FROM AUTHOR]

Plant species of the family Urticaceae have periods of extensive and overlapping flowering. Two genera Urtica ( U. urens L., U. membranacea Poir. in Lam) and Parietaria ( P. judaica L .) are abundant throughout the Iberian Peninsula. Both have substantial allergenic potential, but patient sensitivity is specific to each genus. As a result, interest from the medical profession in the identification of the pollen from these genera has arisen. It would be useful to be able to estimate the relative percentages of pollen of these genera in the air, which would allow clinicians to recommend the appropriate safety measures to patients. Unfortunately, palynologists are unable to distinguish between the species of genera ( Parietaria and Urtica ). Additionally, traditional methods of pollen counting are laborious and therefore not optimal for routine on-line analysis. Recent biometrical analysis enables us to discriminate between pollen species of the genera Parietaria and Urtica , but they fail to solve the problem of genera identification. Alternative methods for counting and distinguishing genera of Urticaceae have long been awaited by medical experts among others. In this paper we present a computational system to discriminate between genera by using image analysis. It is based on the definition and computation of digital shape measures on pollen images taken by an optical microscope. The system correctly classifies more than 86% of all experiments done. A set of shape parameters are tested and the subset with the highest discrimination power includes: area (A), diameter (DM), mean distance to centroide (D mean ) and roundness (R) of the pollen grain. [ABSTRACT FROM AUTHOR]

Angiosperm pollen grains can absorb or release water quickly. The respective degree of hydration has great influence upon the actual pollen grain shape and is, to a certain extent, reversible (harmomegathic effect). In the hydrated condition the majority of pollen grains are usually spherical, but in the dry condition they are infolded in a highly variable manner. This paper demonstrates many kinds of infolding within dicotyledonous tricolp(or)ate pollen from several angiosperm families. In most cases the foldings are directionally oriented, but it is only possible to predict the final form in dry condition to a limited degree. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyse whether the functional diversity of the fungal community follows the environmental gradients as much as vascular plants. After determination of the Ellenberg's indicator values on the basis of 602 cormophyte species occurring in 110 permanent plots across Central Europe, the relation between soil fungi and the abiotic factors as defined by Ellenberg's indicators has been evaluated. The palynological assessment proves that not the fungal occurrence, but the concentration of fungal remains is the most appropriate tool to unravel causal links between the belowground microflora and the soil abiotic factors. The analyses show a striking dichotomy within the fungal community. First, the logarithms of fungal diversity and hyphal density show close but opposite relationships with light, moisture, soil reaction and nitrogen availability. Second, fungal functional groups show parallel, decreasing trends for soil reaction and nitrogen availability. Aside from the mycorrhizal network as a whole (ericoid, EM and AM), we demonstrate that the degree of ecological information supplied by the different trophic levels (litter-related fungi, fimicolous fungi, wood-related fungi and strictly ericoid mycorrhizal fungi) is much greater than expected from previous studies. [ABSTRACT FROM AUTHOR]

This paper presents data of airborne pollen concentration of Pinus, Platanus, Quercus, Betula, Poaceae and Castanea, the most abundant pollen types, during the last eight years, in Santiago de Compostela (NW Iberian Peninsula). We determined their respective principal pollen release periods and analysed statistically the influence of the main meteorological parameters on their pollen concentration, obtaining a negative correlation with precipitation and a positive correlation with temperature, in the majority of the cases, during these years. A detailed study of accumulated pollen values, in relation to accumulated average temperatures and the precipitation distribution, enabled us to establish a relationship between these parameters and the principal pollination period of each of these taxa. [ABSTRACT FROM AUTHOR]

This paper describes the pollen morphology of Cathaya from well-dated Mio-Pliocene sediments in the Himi area of Toyama Prefecture in central Japan. The geological distribution of the genus shows that it was present around the study area and in northern Japan from at least the Middle Miocene to the Early Pleistocene. The genus flourished in the Early Pliocene when the climate was warm, and became extinct in Japan in or after the Early Pleistocene because of climatic deterioration. [ABSTRACT FROM AUTHOR]

The Podostemaceae, or river-weeds, comprise 46 genera and 270 species of dicots and are the largest family of strictly aquatic angiosperms. Despite the large size, specialized habitats, and enigmatic morphology of the family, relatively little is known about the palynology of Podostemaceae. In the current paper, pollen morphology and ultrastructure of Marathrum schiedeanum are described. Pollen grains are relatively small, spheroidal, and tricolpate to spiraperturate. The exine has a microechinate ornament, a tectate-granular sexine and a relatively thick nexine in non-apertural regions, and a semitectate sexine and thinner nexine in apertural regions. Although aperture variation occurs in the family, this is the first report of the spiral aperture type in Podostemaceae. The spiraperturate condition appears to be derived in river-weeds, as does the granular pollen wall, which represents a reduction of the typical columellae found in eudicots. [ABSTRACT FROM AUTHOR]

Pollen allergy remains insufficiently studied in the Philippines despite its global significance. This community-based, cross-sectional study thus determined the sensitisation profile of Filipino individuals to pollen allergens from selected grass species (Zea mays, Saccharum spontaneum, and Dichanthium spp.) and tree species (Mangifera indica, Delonix regia, and Peltophorum pterocarpum). Study subjects (n = 523), 2–70 years old, and residents of Bustos, Bulacan, Mayorga, Leyte, and Laoag, Ilocos Norte, were recruited from November 2018 to July 2019. Clinical history was evaluated through a self-directed questionnaire, while pollen sensitisation was assessed through skin prick test (SPT) and pollen-specific immunoglobulin E enzyme-linked immunosorbent assay (sIgE ELISA). Correlation and multiple logistic regression analyses were performed to identify significant relationships between pollen sensitisation and demographic characteristics. Of the 523 study subjects, 38.24% reported symptoms of allergic rhinitis, 32.70% reported atopic dermatitis, and 30.02% reported allergic asthma. Participants were mainly sensitised to M. indica (32.70%). More males were sensitised at earlier age groups than females. Alternatively, females had increased odds of reporting allergic rhinitis and more than one type of allergic disease. Sensitisation to tree pollen, age, smoking, and secondhand smoking status were also significant predictors (p ≥ 0.05). Smoking status, sex, age, family history, and sensitisation to tree pollen were significant risk factors associated with allergic diseases. [ABSTRACT FROM AUTHOR]

Wind-blown pollen (pollen rain) is a major contributor to element cycling in modern forests and aquatic ecosystems, particularly in high-latitude and acidic settings where nutrients are a limiting factor. The rich package of proteins, nitrogen and phosphorus residing within pollen is, nonetheless, inaccessible to most organisms, owing to the indigestible sporopollenin walls. Saprotrophic breakdown by fungi, and some non-fungal microorganisms, can make nutrients bioavailable, and represents a key trophic link in element cycling and the transfer of organic carbon. Little is known about when micro-saprotrophs first adapted to exploit pollen, thus establishing this crucial step in the evolution of modern terrestrial ecosystems. One approach is to examine the rich fossil record of palynomorphs. Here we describe translucent bodies referable either to fungi (Chytridiomycota) or water moulds (Oomycetes) within the pollen of glossopterid gymnosperms and cordaitaleans, and fern spores from silicified Permian (Guadalupian–Lopingian) peats of the Toploje Member, Bainmedart Coal Measures, Prince Charles Mountains, Antarctica. These probable holocarpic thalli or oospores exploited the nutrient-rich microgametophyte tissue of dispersed miospores in high-palaeolatitude wetlands. The exceptional preservation of fossil microorganisms in permineralised peats offers insights into the deep-time evolution of intimate ecological relationships, otherwise known only among extant biotas. Permineralisation has preserved sub-micron details of these delicate and cryptic saprotrophs that likely played key roles in cycling nutrients in the acidic forest mires of the Permian. Our study reveals that the extensive recapture of spore/pollen-derived nutrients via saprotrophic digestion was already at play in the high-latitude ecosystems of the late Palaeozoic. [ABSTRACT FROM AUTHOR]

This paper intends to elucidate the anther wall development, pollen wall development and exine substructure of Uraria crinita (L.) Desv. ex DC. (Fabaceae). The undifferentiated anther is ovoid-shaped and tetrasporangiated. The anther wall development is basic type, which is comprised of an epidermis, an endothecium layer, two middle layers and a tapetum. Anther-tapetum is glandular type and the cells are uniseriate and uninucleate. Pollen grains are tricolporate and 2-celled at the time of shedding. Before protectum development begins, a glycocalyx layer is inserted against the callose, and the plasma membrane is invaginated, exclusive of the future apertures. Subsequently, the probacula are elongate under the protectum and arise basally from the plasma membrane. The foot layer and endexine formation are concomitant with the callosic wall dissolution. The foot layer is thin and interrupted, but the endexine is thick and continuous. The intine is initially in the vacuoled stage. The substructure in the tectum, bacula and endexine is the same as a rod-shaped in side view. It composed of the loop like striate elements. [ABSTRACT FROM AUTHOR]