Pollen Samples Research Articles

Viral Diversity in Mixed Tree Fruit Production Systems Determined through Bee-Mediated Pollen Collection

Commercially cultivated Prunus species are commonly grown in adjacent or mixed orchards and can be infected with unique or commonly shared viruses. Apple (Malus domestica), another member of the Rosacea and distantly related to Prunus, can share the same growing regions and common pathogens. Pollen can be a major route for virus transmission, and analysis of the pollen virome in tree fruit orchards can provide insights into these virus pathogen complexes from mixed production sites. Commercial honey bee (Apis mellifera) pollination is essential for improved fruit sets and yields in tree fruit production systems. To better understand the pollen-associated virome in tree fruits, metagenomics-based detection of plant viruses was employed on bee and pollen samples collected at four time points during the peak bloom period of apricot, cherry, peach, and apple trees at one orchard site. Twenty-one unique viruses were detected in samples collected during tree fruit blooms, including prune dwarf virus (PDV) and prunus necrotic ringspot virus (PNRSV) (Genus Ilarvirus, family Bromoviridae), Secoviridae family members tomato necrotic ringspot virus (genus Nepovirus), tobacco necrotic ringspot virus (genus Nepovirus), prunus virus F (genus Fabavirus), and Betaflexiviridae family member cherry virus A (CVA; genus Capillovirus). Viruses were also identified in composite leaf and flower samples to compare the pollen virome with the virome associated with vegetative tissues. At all four time points, a greater diversity of viruses was detected in the bee and pollen samples. Finally, the nucleotide sequence diversity of the coat protein regions of CVA, PDV, and PNRSV was profiled from this site, demonstrating a wide range of sequence diversity in pollen samples from this site. These results demonstrate the benefits of area-wide monitoring through bee pollination activities and provide new insights into the diversity of viruses in tree fruit pollination ecosystems.

A high-throughput protocol for testing heat-stress tolerance in pollen

AbstractViable pollen is crucial for fertilization, but pollen is generally highly susceptible to heat stress. A quick, reliable method for testing the heat-stress tolerance of pollen is needed to improve the heat-stress tolerance in plants, but current methods require considerable space and labor. In addition, many such methods only test tolerance to a single constant temperature, making it time-consuming to screen heat tolerance over a wide temperature range and to examine the dynamics of pollen viability at different temperatures. To address this issue, we aimed to: (1) develop an easy, reliable method for measuring pollen viability at different temperatures; and (2) identify the best temperature range for screening pollen with high heat-stress tolerance. We harvested mature pollen from wheat (Triticum aestivum) plants and transferred it to a 96-well plate filled with liquid medium containing sucrose. We placed the plate in a PCR machine operating under a gradient PCR program to simultaneously test a range of temperatures. After incubating the pollen for 4 h, at temperatures ranging from 21.9 to 47 °C, we examined the pollen grains under a light microscope and employed a specific image analysis pipeline to assess the effects of temperature on pollen morphology, germination, and tube growth. This method facilitated the high-throughput screening of many pollen samples, enabling rapid, reliable, and precise analysis of pollen viability in response to temperature. Our approach should be applicable to other plant species and could be used to identify quantitative trait loci or genes influencing heat stress tolerance in pollen for breeding programs.

Airborne microplastic monitoring: Developing a simplified outdoor sampling approach using pollen monitoring equipment

A novel, yet simple, airborne microplastic (MP) sampling approach using global pollen monitoring equipment was applied to identify, characterise and quantify outdoor airborne MPs for the first time. Modification of Burkard spore trap tape adhesive provided particle capture and facilitated downstream spectroscopy analysis. 36 polymer types were identified from a total of 21 days sampling using Burkard spore traps at two locations (United Kingdom and South Africa). MPs were detected in 95 % of daily samples. Mean MP particle levels were 2.0 ± 0.9 MP m-3 (11 polymer types) in Hull (U.K.), during March, 2.9 ± 2.0 MP m-3 (16 types) in Hull in July, and 11.0 ± 5.7 MP m-3 (29 types) in Gqeberha, (S.A.) in August 2023. The most abundant polymer type was nylon (Gqeberha). The approach was compared with two passive sampling methods whereby 27 polymer types were identified and of these, 6 types were above the limit of quantification (LOQ), with poly(methacrolein:styrene) (PMA/PS) the most abundant. Irregularly shaped MPs < 100 µm in length were predominant from all sampling approaches. For the first time, airborne MPs were chemically characterised and quantified using volumetric pollen sampling equipment, representing a viable approach for future airborne MP monitoring.

Optimisation of bioaerosol sampling using an ultralight aircraft: A novel approach in determining the 3-D atmospheric biodiversity

Bioaerosols, such as pollen and fungal spores, are routinely monitored for agricultural, medical or urban greening practices, but sampling methodology is largely relying on techniques more than half a century old. Moreover, biomonitoring campaigns often take place in urban environments, although sources can be located outside cities’ borders with ampler vegetation. Therefore, the question arises whether we are accurately picturing the biodiversity and abundance of regional bioaerosols and whether those locally detected might derive from long-distance transport, horizontally or vertically. To answer the above, we used novel, mobile monitoring devices, and aerial measurement units, like aircrafts, so as to explore bioaerosol concentrations at a variety of altitudes.An ultralight aircraft was equipped with a sampling device for bioaerosols. The device consisted of duplicate isokinetic impactors that match the physical functioning and the microscopic quantification method of the widely used ground-based Hirst-type impactors. Isokinetic airflow was realized by adjusting the air flux at the impactors’ inlet to the airspeed of the aircraft. Three campaigns were made, where the comparability, efficiency and accuracy of different sampling devices were determined, namely of the abovementioned impactor, and of the mobile conventional Hirst-type pollen sampler. The campaigns involved measurements from ground level (0 m altitude) up to 900 m (above ground level (agl)) via flights.Our results showed that aircraft-based airborne pollen concentration measurements were consistently higher than those of all other devices, regardless of the altitude and sampling time. It is noteworthy that the pollen concentration exceeded 500 pollen grains/m3 at >900 m of altitude, this concentration being 1.77 times higher than that simultaneously measured at ground level. Likewise, the diversity of pollen was also higher at higher altitude.Our results indicate the usability and superiority of small aircraft and high-flow impactors for research, achieving higher biodiversity and abundance over a shorter sampling interval compared to conventional volumetric techniques. Higher pollen amounts at higher altitudes also point at the necessity to monitor bioaerosols across the vertical dimension, especially in densely populated areas and high-traffic air space.

Pollen atlas from bat guano deposits in southeastern Amazonia

The botanical literature lacks pollen resources such as atlases and identification keys for bat guano deposits. To address this gap, our dataset describes modern pollen and spore assemblages from five caves in the Carajás region, southeastern Amazonia. A comprehensive atlas featuring illustrations and detailed descriptions of pollen and spores was created using both original and published data. It aims to simplify the identification of different pollen and spores taxa within bat guano deposits, featuring light micrographs and descriptions of 105 pollen taxa, including 81 arboreal and shrub taxa, 11 lianas taxa, 7 herbaceous taxa, 3 palm taxa, and 3 ferns. Among the total pollen assemblage, entomophilous plant taxa represented 42.8%, followed by wind-pollinated taxa at 9.5% and bat-pollinated taxa at 7.6%. Our data indicate that bat guano can provide valuable information on plant taxa that are underrepresented in more traditional pollen sampling sites such as peat bogs and lake sediments.

Physicochemical Characterization and Antioxidant Activity of Algerian Bee Pollens: Exploring Geographical Influences

Abstract: This research study offers a comprehensive physicochemical analysis and assessment of antioxidant activity for 15 bee pollen samples collected from diverse regions of Algeria. The analysis included a wide range of parameters such as moisture content, sugar composition (fructose, glucose, and sucrose), ash, electrical conductivity, free acidity, pH, total flavonoid (TFC) and phenolic (TPC) contents, as well as protein and lipid contents. Additionally, the study evaluated the antioxidant activity using two methods: DPPH radical scavenging activity and ferricreducing antioxidant power (FRAP).The results revealed higher values of pH, free acidity, and electrical conductivity, indicating potential variations in the physicochemical properties of bee pollen samples from different regions. Notably, the samples were further distinguished by high total phenolic content (26.23 mg GAE/g), flavonoid content (4.73 mg QE/g), and protein content (21.7%), along with a unique mineral composition. The analysis also demonstrated the highest total antioxidant capacity and a marked correlation with total phenolics. This study highlights the influence of geographical factors on the physicochemical properties and antioxidant activity of Algerian bee pollen. Regional variations underscore the importance of considering geographical factors in evaluating bee pollen quality, nutritional value, and potential health benefits of Algerian bee pollen. This emphasizes their crucial role in functional foods and natural health products. Understanding these variations supplies valuable insights for optimizing the utilization of bee pollen in functional foods, dietary supplements, and pharmaceutical formulations. Further research into environmental factors influencing bee pollen's antioxidant properties could enhance our understanding of its therapeutic potential. other: Further research into environmental factors influencing bee pollen's antioxidant properties could enhance our understanding of its therapeutic potential. Additionally, exploring the potential applications of Algerian bee pollen in functional foods, dietary supplements, and pharmaceutical formulations could provide opportunities for product development and innovation in the food and healthcare industries.

Late-Holocene ecosystem dynamics on Weizhou Island, China: A pollen and historical record of climate change and anthropogenic disturbances

Understanding the mechanisms behind landscape diversity changes on islands, particularly due to historical human interventions, remains a critical challenge in paleoecology. This study addresses this gap by utilizing over 160 pollen samples combined with multi-proxy data and historical records to reconstruct the late-Holocene ecological and environmental dynamics of Weizhou Island, China, over the last 1400 years. Our analyses reveal the evolution of ecosystem diversity and vegetation succession amid climatic fluctuations and anthropogenic pressures, identifying four distinct phases of transformation: (1) A warm and dry climate from 1400 to 850 cal yr BP fostering a savanna ecosystem; (2) A shift to a North subtropical seasonal rainforest under a more humid climate between 850 and 210 cal yr BP, with increased vegetation diversity; (3) The initiation of agriculture and aquaculture, along with a cooler climate from 210 cal yr BP to 1970 CE, marked by human-induced landscape alterations; and (4) A significant transformation from a once-diverse ecosystem to artificial protective forests from 1970 CE to the present. By correlating environmental indicators with historical accounts across eight Chinese dynasties, our study provides detailed insights into the climatic and human factors shaping the island's history. The findings demonstrate that while climatic shifts are primary drivers of biodiversity changes, anthropogenic disturbances also play a significant role. This research underscores the resilience of ecosystems to both climatic and human pressures and emphasizes the importance of integrating historical context into environmental studies.

Analysis of contaminant residues in honey bee hive matrices

Pollinators provide ecological services essential to maintaining our food supply and propagating natural habitats. Populations are in decline due to environmental stressors including pesticides, pathogens, and habitat loss. To better understand the impacts of pesticide exposures on colony health, a field survey in Ohio, USA was conducted to monitor the potential contamination of honey bee colonies by pesticides. Apiaries (n = 10) were situated across an agricultural gradient and samples were collected over a 4-week period encompassing corn planting. Dead bees from entrance traps (DBT), pollen, and in-hive (IH) matrices including bee bread, honey, larvae, and nurse bees were analyzed for a whole suite of pesticides. Out of 210 pesticides targeted, 68 residues were quantified across 306 samples. Neonicotinoids, miticides, and fungicides were the dominant pesticide classes identified throughout all the matrix types. Neonicotinoids were detected at higher concentrations and at higher frequencies compared to fungicides, specifically in field pollen samples. DBT also contained high concentrations of these two contaminant classes, although detection frequencies for neonicotinoids were typically lower. Overall, herbicides and non‑neonicotinoid insecticides were found with low frequency and at low concentrations. For most pesticide classes, trends for the mean concentrations were DBT > IH nurse bees > field pollen > IH larvae > IH honey. Pesticides were detected in 100 % of samples with concentrations ranging from 0.01 ppb (diphenylamine) to 2790 ppb (clothianidin). All samples were contaminated with at least two pesticide residues, while 19 samples presented over ten detects and maximum detections of 20 in DBT. Pesticide residues were positively correlated with agricultural gradients across sites and sampling periods. These findings reveal that foraging leads to the exposure of the entire colony to a wide range of pesticides. Moreover, residues determined in DBT serve as an effective proxy for monitoring hive matrices with significantly less disturbance to active hives.

Increased rupture of cypress pollen type due to atmospheric water in central and southeastern Spain

This study aims to investigate the meteorological variables determining Cupressaceae pollen grain disruption in the environment. A parallel sampling of pollen grains and disrupted Cupressaceae pollen grains was performed in six cities using two Spanish aerobiological networks. The pollen concentrations, disrupted pollen concentrations, percentage of disrupted pollen and number of days when the percentage of disrupted pollen was above or equal to 50 % were quantified during two pollen seasons. The concentrations were determined following the standardised method EN 16868. Results show that the concentrations of pollen grains and disrupted pollen grains were not determined by geographical features and rarely by bioclimatic variables or indexes but by the ornamental use of the specimens in the vicinity of the pollen sampler, highlighting the possibility of using management practices to reduce exposure to allergens in the cities. African dust outbreaks coincided with higher concentrations of pollen grains and disrupted pollen grains, but the reduced percentage of disrupted pollen grains pointed to a non-causal relationship with long-distance transport. The effect of wind and maximum gusts remained negligible. The triggering factor for pollen disruption was the amount of water in the atmosphere, mainly reported as relative humidity. Rainfall increased the effect of disruption due to pollen grain swelling caused by its wash-out effect. The higher the relative humidity, the higher the disrupted pollen concentrations. This aligns with the mechanism of Cupressaceae reproduction since the family needs a water medium in the form of pollination droplets for the pollination tube to develop and the pollen grain to perform its biological function. Therefore, people that develop allergic symptoms to Cupresaceae pollen should avoid exposure during days with high relative humidity in the main pollen season.

Seasonal variation and characterisation of pollen collected by honeybee Apis mellifera scutellata Lepeletier in southwest Ethiopia

The ability of honeybees to successfully grow, reproduce and build strong colonies and produce honey depends on their ability to obtain enough resources from flowering plants within appropriate seasons. However, little is known about seasonal variations and characterisation of honeybee pollen collected in Ethiopia. Therefore, to address this, a total of 2160 pollen samples were collected from five districts in different seasons for two years. The pollen samples were acetolysed and taxonomically identified. The pollen type was classified into frequency categories based on its relative abundance. Diversity indices and species richness were also calculated and compared between districts and seasons. The highest species richness was recorded in Guraferda district, while the lowest was recorded in Godare district. The spring season was considered the most suitable as it has the highest richness in all districts. The ‘predominant’ and ‘secondary’ pollen sources were identified from different plant genera in Asteraceae (62.23%), Mimosaceae (23.59%), Myrtaceae (43.76%), Poaceae (27.25%), Rubiaceae (36.64%), Combretaceae (28.14%), Euphorbiaceae (18.97%), Burseraceae (16.35%), Convolvulaceae (16.52%), Solanaceae (21.40%), Icacinaceae (17.86%), and Dichapetalaceae (16.35%). Terminalia spp. (Combretaceae) had the highest pollen counts and are common in the area. Other species with significant pollen counts included Acacia spp. (Mimosaceae), Croton macrostachyus (Euphorbiaceae), Eucalyptus camaldulensis (Myrtaceae), Vernonia spp. (Asteraceae) and Iodes spp. (Icacinaceae). This study indicated that southwest Ethiopia has great potential for honey production and beekeeping business based on the study of pollen collected. Thus, these results help as a guide to the optimal use of flora resources by a honeybee in the areas.

Comparison of Olea pollen sampling between gravimetric and volumetric traps (NW of Morocco)

Olea pollen is considered one of the most critical causes of respiratory allergic disease in the Mediterranean region, contributing to different symptoms in allergic sufferers. Due to the high increase in the prevalence of olive pollen caused by the expansion of cultivated areas especially in the Mediterranean region, the aim of this study was to examine the Olea pollen sampling efficiency between gravimetric and volumetric pollen traps over the period 2018–2022. Our data demonstrated that Olea pollen season start-date was generally recorded earlier with volumetric trap than shown with gravimetric method. Moreover, the peak dates occurred mainly in May for the years studied. Across the entire period, the greatest pollen concentrations were reached in the week 11th and >60 % of the total Olea pollen were already reached after the ninth week of sampling in 2020. In general, the evolution of pollen sampling for both methods demonstrates similar temporal development. Variations in the seasonal pollen integral could be attributed to the elevation above ground level at which the traps were placed, exposure to regional winds, the influence of long-range transported pollen and the mode of pollen transport. The findings indicate that the gravimetric method was equally practical as the volumetric method in estimating airborne pollen.

Development and validation of a green analytical method for determining fourteen bisphenols in bee pollen by ultra-high-performance liquid chromatography-tandem mass spectrometry

A new analytical method was developed and validated to determine fourteen bisphenols (A, B, C, E, F, M, P, S, Z, AF, AP, BP, FL, PH) in bee pollen using ultra-high-performance liquid chromatography-tandem mass spectrometry. Two different sample treatments were proposed and evaluated: one based on the QuEChERS (quick, easy, cheap, effective, rugged & safe) approach and the other utilizing microextraction with a supramolecular solvent (SUPRAS). In both cases, average analyte recovery ranged between 71 % and 114 %, and the matrix effect was between −45 % and +5 %, although it was not significant when using the QuEChERS-based method (<±20 %). The environmental impact of both sample treatments was assessed using different analytical metrics, with both procedures classified as environmentally friendly, though slightly better results were obtained for SUPRAS. The method was fully validated, showing that the QuEChERS approach had better overall performance, particularly regarding sensitivity and matrix effect. Consequently, the QuEChERS methodology was applied to determine bisphenols in thirty bee pollen samples from different Spanish regions. Residues of three bisphenols (M, P, and S) were detected, although only bisphenol S was quantified in several samples at low concentration levels (<7 μg kg−1), which is below the established specific migration limit (SML; 50 μg kg−1). However, regarding human health, the estimated daily intake, target hazard quotient, and hazard index assessed were higher than acceptable limits, suggesting a potential risk for human consumers.

Microbial community diversity analysis of kiwifruit pollen and identification of potential pathogens.

The kiwifruit industry typically uses commercial pollen for artificial pollination. However, during the collection of male flowers and pollen production, pollen can be easily contaminated by pathogenic bacteria that cause diseases such as canker and flower rot. Consequently, it is crucial to understand the structure of the pollen microbial community. This study employed Illumina high-throughput sequencing technology to analyze the fungal and bacterial composition in pollen samples from various regions in Shaanxi Province. Concurrently, potential pathogenic strains were isolated using traditional microbial isolation and cultivation techniques, and their molecular identification was performed through 16S rDNA sequence analysis. A tieback test was conducted on healthy branches to verify the pathogenicity of the strains. The results revealed a rich diversity of fungi and bacteria in kiwifruit pollen. At the phylum level, pollen fungi were mainly distributed in Ascomycota, and bacteria were mainly distributed in Proteobacteria and Firmicutes. The dominant fungal genera were Mycosphaerella, Aspergillus, and Cladosporium; the dominant bacterial genera were Weissella, Pantoea, Enterobacter, and Pseudomonas, respectively. Additionally, both Erwinia persicina and Pseudomonas fluorescens, isolated from pollen, exhibited high pathogenicity toward healthy kiwifruit branches. These findings contribute to a deeper understanding of the microbial diversity in commercial kiwifruit pollen used for mass pollination.

Determination of potentially toxic metals and natural radionuclides in airborne pollens produced different urban environments in Turkey and health risk assessment

ABSTRACT Air pollutants are associated with potentially toxic metals (PTMs) and natural and/or artificial radionuclides, which can pose a major threat to human and environmental health. Pollens can be utilized as a bioindicator to determine the level of air pollution in urban areas. In this study, the concentrations of PTMs and natural radionuclides in 35 airborne pollen samples of 22 species belonging to Pinaceae, Cupressaceae, Araucariaceae, Betulaceae, Salicaceae, and Oleaceae families grown in different urban areas in Turkey were determined using an energy-dispersive X-ray fluorescence spectrometry. For the first time, non-carcinogenic and radiologic health risk assessments for adults were done, estimating hazard index (HI) and annual effective dose (AED), respectively. The concentrations of Fe, Mn, Zn, Ti, Sr, Cu, Ni, Co, Cr, V and Pb analyzed in airborne pollen samples varied from 52.1 to 3078.0, 26.1 to 159.6, 15.6 to 199.7, 9.1 to 282.2, 1.0 to 128.4, 5.0 to 40.1, 5.4 to 23.6, <LD to 11.3, 1.6 to 26.6, <LD to 11.1 and <LD to 5.7 mg/kg, respectively. The average concentrations of K (2%), Th (1.3 mg/kg) and U (1.0 mg/kg) were converted into the activity concentrations (in Bq/kg) of 40K (595.8), 232Th (5.2) and 238U (11.8), respectively. All HI and AED values revealed a very low non-carcinogenic and radiological health risk due to exposure to all PTMs and radionuclides in the pollen samples studied.

Shared use of a mass‐flowering crop drives dietary niche overlap between managed honeybees and bumblebees

Abstract Resource competition between wild pollinators and managed honeybees (Apis mellifera) has the potential to detrimentally impact insect biodiversity as well as wild plant and crop pollination. As honeybees are central place foragers, their competitive impact on wild bees is expected to be structured by hive proximity, in conjunction with foraging decisions related to landscape‐level resource availability. Yet, how these factors structure dietary niche overlap between wild bees and managed honeybees remains unclear. We conducted a field experiment in seminatural grasslands, where honeybee foraging densities and niche overlap with buff‐tailed bumblebees (Bombus terrestris) were measured at four distances (&lt;100, 500, 1000 and 2000 m) from experimentally placed apiaries, during and after the blooming period of mass‐flowering oilseed rape (Brassica napus). We measured honeybee foraging densities using standardized transect surveys, and quantified species diet composition and dietary niche overlap from pollen samples collected from both bee species. Honeybee foraging densities were highest near apiaries and declined sharply beyond 500 m from the apiaries. However, niche overlap was unrelated to hive proximity but positively related to the availability of oilseed rape. Furthermore, there were significant inter‐ and intraspecific differences in pollen diet composition and breadth throughout the season. Synthesis and applications: Niche overlap between honeybees and bumblebees in agricultural environments was due to resource sharing of mass‐flowering oilseed rape. When both honeybees and bumblebees predominantly forage on wild plants, they maintain distinct pollen diets, suggesting there is a low risk of resource competition between these generalist taxa. Conservation actions that promote floral resource availability and diversity in agricultural landscapes are crucial to maintain niche differentiation between managed honeybees and wild bees.

Aboriginal earth mounds and ENSO on the Calperum floodplain, Murray-Darling Basin, South Australia

This paper presents new data derived from pollen, starch and radiocarbon samples that were collected from six Aboriginal earth (oven) mounds and middens on the Calperum and Pike floodplains, Murray-Darling Basin (MDB), South Australia (SA). Analyses of these samples were undertaken in order to enhance our understanding about the Holocene lifeways of Aboriginal people living in this region. The results from these analyses, combined with published data about the mounds’ contents, relevant ethno-historical information and climate data, allow us to infer that Aboriginal people adopted, in this region, an innovative food production system about 3800 years ago. Further, we argue that the timing of the change suggests this was in response to adverse El Niño Southern Oscillation (ENSO) related weather patterns and consequently fluctuations in both terrestrial and aquatic food resources.

Diversity of plant pollen sources, microbial communities, and phenolic compounds present in bee pollen and bee bread.

The pollination of several crops, as well as wild plants, depends on honeybees. To get the nutrients required for growth and survival, honeybee colonies are dependent on pollen supply. Bee pollen (BP) is partially packed in honeycomb cells and processed into beebread (BB) by microbial metabolism. The composition of pollen is highly variable and is mainly dependent on ecological habitat, geographical origin, honey plants, climatic conditions, and seasonal variations. Although there are important differences between the BP and the BB, little comparative chemical and microbiological data on this topic exists in the literature, particularly for samples with the same origin. In this study, BP and BB pollen samples were collected from two apiaries located in the Campania and Molise regions of Southern Italy. Phenolic profiles were detected via HPLC, while antioxidant activity was determined by ABTS·+ and DPPH· assay. The next-generation sequencing (NGS) based on RNA analysis of 16S (rRNA) and internal transcribed spacer (ITS2) regions were used to investigate the microbial community (bacteria and fungi) and botanical origin of the BP and BB. Chemical analysis showed a higher content of flavonols in BP (rutin, myricetin, quercetin, and kaempferol), while in BB there was a higher content of phenolic acids. The NGS analysis revealed that the microbial communities and pollen sources are dependent on the geographical location of apiaries. In addition, diversity was highlighted between the microbial communities present in the BP and BB samples collected from each apiary.

Return of the Phrag-i: evaluating sexual reproduction mechanisms amenable to dieback recovery and potential invasiveness across Phragmites australis haplotypes

Phragmites australis is one of the most invasive wetland plants on the planet with both native and invasive haplotypes occurring in the United States. Three Phragmites haplotypes (Delta-, EU- and Gulf-types) co-occur in marshes of the Mississippi River Delta (MRD), where a recent dieback of Phragmites has prompted investigations about the potential for recolonization by seed. In other areas of the US, the invasive EU-type has been shown to spread by seed, yet little is known about reproduction modes of the Delta- and Gulf-types. We conducted a survey at 35 sites along the Mississippi River Delta region in southeast Louisiana to examine the potential for sexual reproduction across haplotypes as well as the potential for hybridization. Seed and pollen samples were collected from Phragmites populations to examine flowering phenology and determine pollen viability of the three lineages. We also conducted a seedbank assay in stands of three haplotypes to test the potential for recruitment by seed. Despite the observed potential for sexual reproduction in Delta- and EU- types, no Phragmites seedlings germinated from the seedbank. EU was the only haplotype to exhibit germination from seeds collected from seed heads. Both spatial separation and temporal isolation in flowering times indicate that hybridization between Phragmites haplotypes in the lower MRD is unlikely. High pollen production, increased pollen production following dieback, and viable seeds in the EU-type suggest that this invasive haplotype has a greater potential to invade new areas and adapt to stressors through sexual reproduction compared to than Delta-or Gulf haplotypes.

Floristic diversity and its relationships with human land use varied regionally during the Holocene

Humans have caused growing levels of ecosystem and diversity changes at a global scale in recent centuries but longer-term diversity trends and how they are affected by human impacts are less well understood. Analysing data from 64,305 pollen samples from 1,763 pollen records revealed substantial community changes (turnover) and reductions in diversity (richness and evenness) in the first ~1,500 to ~4,000 years of the Holocene epoch (starting 11,700 years ago). Turnover and diversity generally increased thereafter, starting ~6,000 to ~1,000 years ago, although the timings, magnitudes and even directions of these changes varied among continents, biomes and sites. Here, modelling these diversity changes, we find that most metrics of biodiversity change are associated with human impacts (anthropogenic land-cover change estimates for the last 8,000 years), often positively but the magnitudes, timings and sometimes directions of associations differed among continents and biomes and sites also varied. Once-forested parts of the world tended to exhibit biodiversity increases while open areas tended to decline. These regionally specific relationships between humans and floristic diversity highlight that human–biodiversity relationships have generated positive diversity responses in some locations and negative responses in others, for over 8,000 years.

Development of flour confectionery products using physiologically valuable beekeeping products

The current tasks facing specialists involved in the production and circulation of food products is the creation of products that are balanced in terms of physiologically valuable ingredients. The formation of cookies with a modified recipe composition can change the perception of cookie descriptors. So, a desirable aspect is the search for physiologically valuable ingredients that enrich the finished product and meet the requirements of consumers when assessing its consumer properties, characteristic of the geographical location of the regions of residence and familiar to consumers. The purpose of the research was to develop flour confectionery products using physiologically valuable beekeeping products – bee pollen pellet collected in various regions of the country, and to evaluate the consumer characteristics of the resulting products, taking into account the factors of traditional perception of organoleptic indicators. The objects of the research were samples of bee pollen collected in various regions of Russia. The quality of bee pollen pellet was assessed according to organoleptic indicators: appearance, color, consistency, smell, taste. The assessment of physicochemical quality indicators of bee pollen pellet was carried out using industry-accepted methods. The quality of sugar cookies was assessed using accepted methods for assessing the quality of flour confectionery products. The assessment of the organoleptic quality indicators of the cookies was also carried out hedonistically using the acceptability and preference method and the paired comparison method. The research has confirmed the feasibility of using bee products (bee pollen pellet) in the production of flour confectionery products. Hedonic tests of the perception of flour confectionery products with the addition of beekeeping products and bee pollen have confirmed the traditional perception of the finished products. In general, the proposed solutions for the development of flour confectionery products using physiologically valuable beekeeping products will expand the range of functional food products.