Spatial Bi-hourly Variation of Alternaria Spore Concentration in Worcester, UK

Alternaria species are ubiquitous fungi affecting food security and human health. They are pathogenic on many economically important crops and allergenic to many sensitive people worldwide. Studies from Worcester, UK have shown high a concentration of Alternaria spores, most likely caused by agricultural activities. However, it is unknown whether Alternaria spore concentrations vary geographically throughout Worcestershire. An investigation on the spatial variation in bi-hourly concentration of Alternaria spores in Worcestershire during 2016 and 2017 was conducted. Spores were sampled using two Hirst-type Burkard spore traps at the University of Worcester. One on the rooftop of a building at St John’s Campus and another at Lakeside Campus approximately 7 km away. St John’s Campus is located in the centre of Worcester (52.1970, -2.2421), while Lakeside Campus is located in an agricultural environment (52.2537, -2.2535) with regularly cut grass in the near surroundings. Slides were counted using bi-hourly traverse at x 400 magnification. The total number of spores per slide were converted to the daily mean of spores m¯³ of air. There was a highly positive correlation in the concentration of Alternaria spores between the two sites in both 2016 and 2017. St John’s had the highest peak of spore concentration (213 m¯³) in 2016 and Lakeside had the peak concentration in 2017 (184 m¯³). Concentrations above 100 m¯³ of air were observed more frequently at Lakeside. The study revealed that Alternaria spore concentrations were higher at Lakeside than at St John’s. This could be attributed to spores released from either crops or agricultural activities (e.g. haying or harvesting) or from decomposed grass since the surrounding area is routinely managed. Further work in 2018 will include spore correlations with weather variables from a pair of weather stations located at each site, enabling studies caused by variations in weather and climate. Spatial variation in bi-hourly spore concentrations is useful information to atopic subjects, health experts and crop pathologists. Keywords: Harvesting. Allergy. Fungal Spores

Spatial and Temporal Variance of Bi-hourly Grass Pollen Concentrations in the Local Surroundings of Worcester, UK

B: Grass pollen is the most important aeroallergen worldwide and the health outcome among sensitive individuals is closely related to exposure. It has been argued that grass pollen concentrations can be expected to vary substantially within the urban environment, partly due to source distribution and partly due to dispersion and deposition mechanisms. Most studies conducted on local spatial and temporal variance of pollen concentrations are from one season. Only a few studies include multiple seasons and the results are inconclusive. The patterns and factors responsible for local spatial and temporal pollen variance are still largely unknown. Bi-hourly pollen data provides finer temporal resolution than the standardized daily data otherwise used. Bi-hourly data collected from two sampling sites are used to investigate local spatial and temporal patterns of grass pollen concentrations in Worcester. M: Grass pollen was sampled from two locations in Worcester during the years 2016 and 2017 using a Burkard sampler. Daily and bi-hourly grass pollen concentrations were investigated for temporal and spatial variance using statistical methods by comparing years and locations. The investigation is being repeated for the year 2018. R: Preliminary results from 2016 and 2017 suggest that there is a high spatial correlation for the bi-hourly concentrations in 2016 but not in 2017. In 2016, all recorded peaks except one coincide with a corresponding peak. In 2017, the highest peak coincided with a corresponding peak but the rest of the data did not. Results from 2018 are currently unknown. C: Spatial and temporal variance in grass pollen concentrations fluctuates between years and locations. Peak concentrations tend to have the highest correlations compared to low concentrations. The results show that at least two years of data are needed to establish potential autocorrelation between nearby sites. Future work needs to include longer time-series, more locations and local grass source maps to understand key underlying factors of localized grass pollen concentrations

Using qPCR and microscopy to assess the impact of harvesting and weather conditions on the relationship between Alternaria alternata and Alternaria spp. spores in rural and urban atmospheres.

Alternaria is a plant pathogen and human allergen. Alternaria alternata is one of the most abundant fungal spores in the air. The purpose of this study was to examine whether Alternaria spp. spore concentrations can be used to predict the abundance and spatio-temporal pattern of A. alternata spores in the air. This was investigated by testing the hypothesis that A. alternata dominates airborne Alternaria spp. spores and varies spatio-temporally. Secondarily, we aimed at investigating the relationship between airborne Alternaria spp. spores and the DNA profile of A. alternata spores between two proximate (~ 7 km apart) sites. These were examined by sampling Alternaria spp. spores using Burkard 7-day and cyclone samplers for the period 2016-2018 at Worcester and Lakeside campuses of the University of Worcester, UK. Daily Alternaria spp. spores from the Burkard traps were identified using optical microscopy whilst A. alternata from the cyclone samples was detected and quantified using quantitative polymerase chain reaction (qPCR). The results showed that either A. alternata or other Alternaria species spores dominate the airborne Alternaria spore concentrations, generally depending on weather conditions. Furthermore, although Alternaria spp. spore concentrations were similar for the two proximate sites, A. alternata spore concentrations significantly varied for those sites and it is highly likely that the airborne samples contained large amounts of small fragments of A. alternata. Overall, the study shows that there is a higher abundance of airborne Alternaria allergen than reported by aerobiological networks and the majority is likely to be from spore and hyphal fragments. [Abstract copyright: © 2023. The Author(s).

Air mass trajectories and land cover map reveal cereal crops as major local sources of Alternaria spores in Worcester and Leicester, UK.

Alternaria is a plant pathogen and human allergen. Agricultural areas are known sources of Alternaria spores. Transport of Alternaria spores may occur between such geographical regions. This study examined Alternaria spore abundance and potential pathways for atmospheric transport of the spores between the cities of Worcester and Leicester in the UK, both surrounded by agricultural land. Alternaria spores were sampled using Burkard volumetric samplers for the period 2016-2018 at Worcester and Leicester, located ~90 km apart. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and UK’s land cover map for crops were used to examine the relationship between air mass trajectories and potential source areas of Alternaria spores at the two locations during an episode (27 Jul-07 Aug 2017) of high spore concentrations. During the 3 years of observation, 61 and 151 days of clinical relevance were recorded at Worcester and Leicester, respectively. Spore concentrations at Leicester were considerably higher than in Worcester. Analysis of the crop map showed higher amounts of winter barley and oilseed rape near to Leicester than Worcester. HYSPLIT calculations showed that during the episode, the air masses arrived at both stations from Ireland and the Atlantic Ocean. Long distance transport probably had a small and equal contribution to the observations at both sites. The hypothesis is therefore that the substantially higher concentrations of Alternaria spores at Leicester are caused by specific local sources with high emission potential: potentially winter barley and oilseed rape. Local sources of winter barley and oilseed rape likely contributed to Alternaria spore concentrations of clinical significance in the urban areas of Leicester and Worcester. The strength of the local sources likely resulted in higher emissions of spores at Leicester than at Worcester. Long distance transport probably had a small but equal contribution to the total spore load at the two stations

Microscale pollen release and dispersal patterns in flowering grass populations

Characterizing pollen release and dispersion processes is fundamental for knowledge advancement in ecological, agricultural and public health disciplines. Understanding pollen dispersion from grass communities is especially relevant due to their high species-specific allergenicity and heterogeneously distributed source areas. Here, we aimed to address questions concerning fine level heterogeneity in grass pollen release and dispersion processes, with a focus on characterizing the taxonomic composition of airborne grass pollen over the grass flowering season using eDNA and molecular ecology methods. High resolution grass pollen concentrations were compared between three microscale sites (<300 m apart) in a rural area in Worcestershire, UK. The grass pollen was modelled with local meteorology in a MANOVA (Multivariate ANOVA) approach to investigate factors relevant to pollen release and dispersion. Simultaneously, airborne pollen was sequenced using Illumina MySeq for metabarcoding, analysed against a reference database with all UK grasses using the R packages DADA2 and phyloseq to calculate Shannon's Diversity Index (α-diversity). The flowering phenology of a local Festuca rubra population was observed. We found that grass pollen concentrations varied on a microscale level, likely attributed to local topography and the dispersion distance of pollen from flowering grasses in local source areas. Six genera (Agrostis, Alopecurus, Arrhenatherum, Holcus, Lolium and Poa) dominated the pollen season, comprising on average 77 % of the relative abundance of grass species reads. Temperature, solar radiation, relative humidity, turbulence and wind speeds were found to be relevant for grass pollen release and dispersion processes. An isolated flowering Festuca rubra population contributed almost 40 % of the relative pollen abundance adjacent to the nearby sampler, but only contributed 1 % to samplers situated 300 m away. This suggests that most emitted grass pollen has limited dispersion distance and our results show substantial variation in airborne grass species composition over short geographical scales

Near-ground Effect of Height on Pollen Exposure

The effect of height on pollen concentration is not well documented and little is known about the near-ground vertical profile of airborne pollen. This is important as most measuring stations are on roofs, but patient exposure is at ground level. Our study used a big data approach to estimate the near-ground vertical profile of pollen concentrations based on a global study of paired stations located at different heights. We analyzed paired sampling stations located at different heights between 1.5 and 50m above ground level (AGL). This provided pollen data from 59 Hirst-type volumetric traps from 25 different areas, mainly in Europe, but also covering North America and Australia, resulting in about 2,000,000 daily pollen concentrations analyzed. The daily ratio of the amounts of pollen from different heights per location was used, and the values of the lower station were divided by the higher station. The lower station of paired traps recorded more pollen than the higher trap. However, while the effect of height on pollen concentration was clear, it was also limited (average ratio 1.3, range 0.7–2.2). The standard deviation of the pollen ratio was highly variable when the lower station was located close to the ground level (below 10m AGL). We show that pollen concentrations measured at >10m are representative for background near-ground levels

Harnessing benefits of finger millet in combating micronutrient malnutrition through genetics and genomic approaches

In developing countries, 80% deaths are attributed to continuous persistence micronutrient deficiency and associated infections and chronic diseases. Traditional crops harbouring health benefitting characteristics and micronutritional richness can deliver a low cost sustainable food-based solution for nutrition and health in such countries. Finger millet, one such traditional crop grown in most marginal areas of Africa and Asia, is a rich source of health benefitting micronutrients, phytochemicals, vitamins and several essential amino acids. The objective of this work is to use advances in genetics and genomics approaches for better understanding the genetic control of these health benefitting traits and to breed them effectively into other staple crops consumed on daily basis. A set of 190 genotypes incorporating a minicore collection of finger millet together with a number of elite breeding lines has been assembled to capture and characterise entire genetic variation associated with such traits in the crop germplasm. These genotypes have been extensively characterised for diversity in micronutrients (such as iron, zinc, calcium, magnesium, sodium, and potassium), protein and anti-nutrients (phytate and oxalate). Large-scale GBS performed on this association panel has generated 156,157 SNPs which are being used in genome-wide association studies. Our work has identified a number of genomic regions in finger millet associated with both the health benefitting traits as well as with other factors that affect their bioavailability. This work will significantly contribute in developing means of assessing how such genetic variations are distributed in other staple crops