Pollinator Diversity Research Articles

Prediction Model for Annual Variation in Total Pollen by Allergenic Trees in Korean Cities.

Pollen forecasting systems can provide information for coping with respiratory allergies. They estimate daily pollen production, dispersal, deposition, and removal based on daily weather conditions to predict daily pollen concentrations and provide allergy warnings. As of 2023, the Korea Meteorological Administration (KMA) provides 2-day forecast of allergenic pollens. However, unlike these models, long-term analysis of annual observations of tree pollen reveal annual variations. Therefore, in this study, we aimed to develop annual prediction models for allergenic tree pollens based on long-term multi-site pollen and meteorological data. Daily pollen concentrations were observed using Hirst-type volumetric spore traps at nine sites in Korea from 1998 to 2021, and daily weather data from the closest KMA stations were utilized. Models were developed to predict the seasonal pollen integral of seven tree species based on monthly mean temperature, wind speed, and total precipitation using three variable selection methods: 1) the t-test based key variable screening followed by linear regression with stepwise procedure (TM), 2) direct linear regression with stepwise procedure from the full variable model (FM), and 3) LASSO regression from the full variable model (LM). Data obtained during 1998-2017 and 2018=2021 were utilized for model development and validation, respectively. The root mean squared error, mean absolute error, mean error, and coefficient of determination (R²) revealed that the TM models were best suited for actual forecasting, even though R² in the TM model was lower than those of the FM and LM models. The annual variation model in this study can be integrated with the daily pollen forecast model by controlling the annual pollen potential, and the accuracy of the daily forecast can be improved accordingly.

Pollination biology of Impatiens capensis Meerb. in non-native range.

Pollination biology in the widespread species Impatiens capensis Meerb. has only been studied in America, specifically in zones of the U.S.A. and Canada. In this study, we investigated the pollination biology of I. capensis using an integrative identification approach using morphological and molecular tools in four populations of Northwest Poland. We also determined and compared the functional characteristics of the pollinators of the introduced species from the study sites and the native ones reported, for the latter collecting information from bibliographic sources. Visitors were identified using standard morphological keys, including identifying and classifying insect mouthparts. Molecular identification was carried out using mitochondrial DNA's cytochrome oxidase subunit I (COI). We morphologically identified 20 species of visitors constituted by 17 pollinators and three nectar robbers. DNA barcoding of 59 individuals proved the identification of 18 species (also 18 BINs). The frequency of pollinator species was primarily made up of representatives of both Hymenoptera (75%) and Diptera (21%). The morphological traits, such as the chewing and sucking mouthparts, small and big body height, and robber and pollinator behavior explained mainly the native and introduced visitors' arrangements that allow pollination success. However, to understand the process comprehensively, further investigation of other causalities in pollination success and understanding the diversity of pollinators in outer native ranges are necessary.

Temporal Patterns of Insect Pollinator Diversity in Relation to Flowering Plant Phenology in the Western Mindanao State University Experimental Forest Area, Upper La Paz, Zamboanga City, Philippines

Temporal Patterns of Insect Pollinator Diversity in Relation to Flowering Plant Phenology in the Western Mindanao State University Experimental Forest Area, Upper La Paz, Zamboanga City, Philippines

Interactive Effect of Honey Bees [Apis mellifera, Apis cerana (Hymenoptera: Apidae)] and Native Bees for Pollination Services in Radish, Raphanus sativus

Radish flowers, being self-incompatible are highly reliant on insect visitors for pollination. Honey bees are effective pollinators of radish. Pollination is influenced by visitation rates, behaviour and pollination effectiveness of pollinators which aid in seedset. We explored bee behaviour known to favour pollination; flowers visited per unit time and time required to process a flower by honey bees and non-Apis bees visiting radish. During our study, 54 species/morphospecies were observed to visit radish flowers, of which Apis cerana indica is predominant. Pollinator effectiveness was measured by means of seed set by flowers receiving a single visit of a specific pollinator as compared to seed set by flowers allowed for open pollination (multiple visits) and was found to be 0.31 and 0.36 for A. cerana and Apis mellifera, respectively. Yield enhancement studies through entomophily showed that, flowers receiving unrestricted visit of pollinators (open control) recorded 265.5% higher yield followed by interaction of two pollinators (A. c. indica + A. mellifera) 198.3%, A. mellifera (163.8%) and A. c. indica (178.3%) with respect to radish flowers allowed only for self-pollination. Pollinator diversity enhanced pollination and seed set in radish. These advantages of pollinator synergies and benefits of biodiversity are increasingly recognized.

Can trait matching inform the design of pollinator‐friendly urban green spaces? A review and synthesis of the literature

AbstractLand use change is a major driver of pollinator decline and loss of pollination services. For plant and pollinator interactions to persist in rapidly changing urban systems, co‐occurring species must share matching traits, including phenological, morphological, and physiological traits. Thus, the knowledge of trait matching among interacting plants and pollinators can aid in the design of pollinator habitats and enhance the conservation value of urban green spaces, but this remains relatively understudied. Here, we review how trait matching facilitates the persistence of interactions and creation of new interactions in urban plant–pollinator networks. We highlight four major urban drivers facilitating the restructuring of plant–pollinator networks through species loss and gain in urban areas. We also show different pathways by which the matching of morphological, phenological, and physiological traits of interacting plants and pollinators is affected by urbanization. Furthermore, we show how the knowledge of functional traits can help to predict novel plant–pollinator interactions in urban environments, including those among exotic species. Finally, we show how the application of trait matching can aid management practices, facilitating the design and creation of sustainable green spaces that will accommodate functionally diverse pollinators and plants within the urban matrix.

Quantifying the impact of nitrogen levels on spring maize varieties (Zea mays L.) in Kanchanpur, Nepal

Maize has tremendous potential for increasing productivity, profitability, and sustainability in agriculture. A crucial obstacle to maximizing yield the suitable maize variety with appropriate nitrogen (N) doses. The current two-factorial research carried out in the farmer's field at Kanchanpur, Nepal, aimed to evaluate the effect of different levels of N on the growth and yield of spring maize varieties. Conducted from February to July 2022, the experiment design was randomized complete block with two factors; where hybrid varieties Bioseed 9220 and Arun-2 were the first factors and four different levels of nitrogen (0, 60, 120, and 180 kg N ha-1) were the second factors. Results showed that 180 kg N ha-1 and Bioseed 9220 treatment produced significantly higher plant height, kernel row-1, kernel row cob-1, cob plant-1, and thousand-grain weight as compared to other doses and Arun-2, respectively. Similarly, Bioseed 9220 and 180 kg N ha-1 treatment had significantly longer days for tasseling and silking. The grain yield of Bioseed 9220 (5.48 t ha-1) was significantly greater than Arun-2 (4.15 t ha-1) and the N level of 180 kg ha-1 had a higher yield (5.11 t ha-1) compared to 120 kg ha-1 (4.8 t ha-1), 60 kg ha-1 (4.78 t ha-1) and least in 0 kg ha-1 (4.56 t ha-1). The result indicates that Bioseed 9220 performs better than Open Pollinated Variety (OPV) Arun-2 in growth and yield attributes. N enrichment also boosts yield and yield-attributing characteristics. Bioseed 9220 with 180 kg N ha-1 should be prioritized among farmers to increase the productivity and yield of maize.

Çanakkale bee pollen: diversity, chemical composition, antioxidant and antibacterial properties

Çanakkale, Turkey, which straddles the continents of Europe and Asia, is a settlement centre with natural beauty divided by the Dardanelles Strait. This study determined the diversity, chemical composition, total antioxidant activity and antibacterial activity of fresh bee pollen obtained from 11 stations in Çanakkale in April–May 2017. The Louveaux (1978) method was modified and used to determine the botanical origin of pollen samples. It was determined that the most prevalent families in the pollen samples were Brassicaceae (23.1%), Cistaceae (22.5%), Rosaceae (11.06%), Papaveraceae (5.36%), Oleaceae (7.52%) and Fabaceae (7.31%). A maximum of 47 and a minimum of 31 components were detected in the chemical composition of bee pollen extracts (BPE) by Gas Chromatography Mass Spectrometry (GC-MS), and it was determined that the main components varied depending on the location. Regarding the total antioxidant capacity of BPE, 2,2-Diphenyl-1-picrylhydrazyl (DPPH) reduction was 100% for all locations except Yenice. Also, the antibacterial activity of BPE against Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Staphylococcus aureus ATCC 29213 could not be determined. These findings showed high bee pollen diversity, chemical composition, and antioxidant capacity in the Çanakkale region. The bee pollen from this area is a natural product that can be used as a food supplement.

Diverse pollen nutrition can improve the development of solitary bees but does not mitigate negative pesticide impacts

Floral resource loss and pesticide exposure are major threats to bees in intensively managed agroecosystems, but interactions among these drivers remain poorly understood. Altered composition and lowered diversity of pollen nutrition may reinforce negative pesticide impacts on bees. Here we investigated the development and survival of the solitary bee Osmia bicornis provisioned with three different pollen types, as well as a mixture of these types representing a higher pollen diversity. We exposed bees of each nutritional treatment to five pesticides at different concentrations in the laboratory. Two field-realistic concentrations of three nicotinic acetylcholine receptor (nAChR) modulating insecticides (thiacloprid, sulfoxaflor and flupyradifurone), as well as of two fungicides (azoxystrobin and tebuconazole) were examined. We further measured the expression of two detoxification genes (CYP9BU1, CYP9BU2) under exposure to thiacloprid across different nutrition treatments as a potential mechanistic pathway driving pesticide-nutrition interactions. We found that more diverse pollen nutrition reduced development time, enhanced pollen efficacy (cocoon weight divided by consumed pollen weight) and pollen consumption, and increased weight of O. bicornis after larval development (cocoon weight). Contrary to fungicides, high field-realistic concentrations of all three insecticides negatively affected O. bicornis by extending development times. Moreover, sulfoxaflor and flupyradifurone also reduced pollen efficacy and cocoon weight, and sulfoxaflor reduced pollen consumption and increased mortality. The expression of detoxification genes differed across pollen nutrition types, but was not enhanced after exposure to thiacloprid. Our findings highlight that lowered diversity of pollen nutrition and high field-realistic exposure to nAChR modulating insecticides negatively affected the development of O. bicornis, but we found no mitigation of negative pesticide impacts through increased pollen diversity. These results have important implications for risk assessment for bee pollinators, indicating that negative effects of nAChR modulating insecticides to developing solitary bees are currently underestimated.

Vegetation response to climate change and human activity in southwestern China since the Last Glacial Maximum

Southwestern China, a biodiversity hotspot, underwent dramatic climate change following the Last Glacial Maximum and intensive human activity also exerted a major impact since the late Holocene. In this paper, we report a pollen record from Yilong Lake in Yunnan Province, southwestern China, to understand vegetation response to long-term climatic variation and human activities at a regional-level over the last 27,000 years. Findings show that temperate and coniferous taxa were dominant before 18 cal kyr BP reflecting the glacial climate. Between 18 and 14 cal kyr BP, thermophilic taxa increased in response to global deglaciation. A notable shift from deciduous to evergreen forests occurred at approximately 14 cal kyr BP, after which pollen concentration increased but pollen diversity decreased. Pollen assemblages indicated dense forests, primarily composed of evergreen oaks developed under warm and strong summer monsoon conditions from 13 to 8 cal kyr BP. High rates of vegetation change occurred during the middle Holocene before vegetation diversity gradually increased during the Holocene Thermal Optimum, with high variability of precipitation in the Yilong Lake region. Anthropogenic forcing progressively became the main factor affecting vegetation composition and vegetation change rates over the past three millennia.

Diversity and biological traits of bees visiting flowers of Cucurbita maxima var. zapallito differ between biodiversity-based and conventional management practices.

Low diversity of pollinators and the modified composition of functional groups of bees have been proposed as the causes of pollination deficiency in cultivated Cucurbitaceae species. Functional groups of bees are determined by traits, such as body size, nesting site, and social behavior. The presence of bees with specific traits can be differentially affected by agricultural management practices. This work aimed to assess how management types (agroecological and conventional) in Cucurbita maxima var. zapallito crops affect the abundance of bees with different biological traits. The study was conducted on four farms located in horticultural areas of central-eastern Santa Fe province, Argentina. A total of 108 10-min censuses were conducted to record bee species abundance in flowers. The species were assigned to categories for each of the three biological traits. A total of 552 individuals, belonging to 16 bee species, were recorded. Honey bees were more abundant under conventional management, whereas the native bees Eucera fervens and other species were more abundant under agroecological management. Species of the categories analyzed (body size: small, medium, and large; nesting site: above-ground cavities or ground-nesting; and social behavior: solitary or social) were present on farms under both management types. We found that management type affected bees, and their effects differed among bees with specific biological traits. Medium-sized and small bees, ground-nesting bees, and solitary bees were found in greater abundance on agroecological farms than on conventional farms. Our data allowed us to explain the diversity and abundance of bees relative to the management type and biological traits of the species. Implications for insect conservation: This study suggests that incorporating biodiversity-based management strategies might increase abundance and richness of native bees with different biological traits, ensuring the free pollination service they provide and a taxonomically and functionally diverse assemblage.

Temporal and spatial variation of floral resources of woody species in a vereda ecosystem: Uniformity and habitat complementarity

Floral resource distribution, pollinator community structure, and flowering season are essential for maintaining and preserving pollination services in ecosystems. In humid Cerrado areas, veredas are considered hygrophilous communities, marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones. Waterlogged portions present dense hygrophilous forests, whereas open areas predominant present herbaceous and shrubby components. We identified the pollination syndromes of woody species in a vereda ecosystem and characterized the pollination resource availability between habitats (hygrophilous forest and open area). The study was conducted on a vereda located in the north of Minas Gerais, Brazil. We characterized pollination syndromes using information on floral attributes, pollinator observations, and a literature survey. We performed phenological monitoring for 24 months and examined the occurrence of flowering using circular statistics. The differences in pollination syndrome occurrence among months and habitats were determined using modularity analysis. We found eight pollination syndromes, with melittophily being the most frequent pollination type among the woody species in the studied vereda. Flowering occurs throughout the year in the community and peaks from September to November during the transition from the dry to the wet season. In hygrophilous forest the species flowered preferentially in November, whereas in open area, preferentially between September and October. The syndromes distribution differed between the habitats, as well as resource availability. This difference between habitats can influence pollinator diversity. Modularity showed complementarity among the habitats, with continuous resource availability throughout the entire ecosystem. Species present in the hygrophilous forest provide their resources mainly during the rainy season, whereas species from the open area, during the dry season. Information on these interactions is necessary to understand the functionality of a vereda ecosystem, through the characterization of the resource's availability, and maintenance of pollination services in the ecosystem. In addition, our results demonstrate the importance of the vereda ecosystem as an important area in the availability of resources for the Cerrado formation. This information can strengthen protection laws and contribute to sustainable practices that boost the conservation of pollinators in the biome.

Complex floral traits shape pollinator attraction to flowering plants in urban greenspaces

Urban greenspaces are recognized as a benefit to pollinator conservation. Selective planting of attractive flowering plants can improve the conservation value of urban greenspaces. However, the functional traits of flowering plants that moderate pollinator preference merits further study. We analyzed 98 ornamental plants and spontaneous plant species for ten categories of floral and plant traits across twelve parks or campus greenspaces in Wuhan, a megacity located in central China. Our results revealed that: (1) Plant species vary enormously in their pollinator visitation rate. (2) For Lepidoptera, the number of individuals to the plot was lower for disk/bowl-shaped flowers than other flower shapes, and it was negatively corelated with corolla tube length. The number of Diptera individuals to the plot was higher for white, red/pink and yellow/orange flowers than blue/violet flowers. (3) Honeybees preferred exotic annual/biennial herbaceous species, with disk/bowl and flag flowers. Solitary bees preferred horizontal, lip or flag flowers. Diptera most frequently visited upward-facing, yellow/orange flower heads and Lepidoptera preferred horizontal, funnel-shaped flowers or flower heads. Blue/violet flowers and a diverse floral orientation were preferred by most pollinator groups. We recommend planting native woody plants (Nandina domestica, Thymus quinquecostatus, Lagerstroemia indica, and Tamarix austromongolica) and attractive exotic plants (Centaurea cyanus, Borago officinalis, Portulaca grandiflora, and Echinacea purpurea) to support multiple pollinator groups. As preferences differ among pollinators, increasing the species richness of flowering plants is conducive to promote overall pollinator diversity.

The Diversity and Abundance of Insect Pollinators Visiting Apple Flowers

A study was conducted to determine the insect pollinators visiting apple flowers. In studies, Apple flowers attracted insects from five orders, including Hymenoptera, Diptera, Lepidoptera, Coleoptera and Thysanoptera. Of all the orders, insects belonging to order Hymenoptera were most abundant. They included honey bee Apis mellifera, Apiscerana, bumble bees Bombus sp. Anthophoride Xylocopafenestrata, X. aestuans X. pubescens, X. valga, Halictidae Halictus spp. Nomia spp. Lasiogllosum spp. Ceratina spp. Melissodes spp., Colletidae Colleteseous, vespidaeVespa orientalis, V. Cincta V. Mandarinia, Polistes hebraeus, megachilidae Osmia spp. Andrenidae Andrenaflaviceps, Formicide Camponotuscompressus. Honeybees were the most abundant of all flower visitors and made up more than 48% of the total.

Diversity and Abundance of Pollinators Affecting Seed Production in Radish (Raphanus sativa)

Diversity and Abundance of Pollinators Affecting Seed Production in Radish (Raphanus sativa)

Diversity and Abundance of Insect Pollinators Affecting Seed Production in Mustard (Brassica napus L.)

Diversity and Abundance of Insect Pollinators Affecting Seed Production in Mustard (Brassica napus L.)

Micrometer insights into Nepeta genus: Pollen micromorphology unveiled

This study provides a comprehensive pollen micromorphology within the Nepeta genus, revealing intricate details about the pollen grains' structure and characteristics. The findings shed light on the evolutionary and taxonomical aspects of this plant genus, offering valuable insights for botanists and researchers studying Nepeta species. The pollen grains of 18 Nepeta species were studied using scanning electron microscopy (SEM) and light microscopy (LM) in Northern Pakistan. At the microscale, pollen quantitative measurements, qualitative traits, and diverse sculpturing patterns were reported and compared. Significant differences in pollen size, shape, ornamentation, and sculpturing patterns were discovered among the Nepeta species. Our data show that exine sculpturing is quite diverse, with most species exhibiting a reticulate perforate pollen pattern. Nepeta connata, Nepeta discolor, Nepeta elliptica, revealed a distinct bireticulate perforate exine stratification. Hexazonocolpate pollen is the most common. Furthermore, the surface membrane attributes of the colpus varied greatly, ranging from rough, scabrate, psilate, to sinuate patterns. Principal Component Analysis (PCA) was used to discover the key factors influencing pollen diversity. PCA results showed that polar and equatorial diameters, colpi size, and exine thickness were the most influential pollen features between Nepeta species. This study adds to our understanding of pollen morphology in the Nepeta genus, offering information on the vast range of characteristics found in this economically important group. The extensive characterization of pollen features provides useful insights for the categorization and differentiation of Nepeta species, adding to the Lamiaceae micromorphology.

PCA and LDA Assessment of the Heavy Metal Contamination in Honey Bees, Bee Pollen and Honey Produced in Urban Areas of Türkiye

Heavy metals are of great importance in terms of environmental pollution. Environmental pollution affects not only humans but also plants and animals. Living organisms with varying sensitivity to various pollutants can be used to assess environmental pollution. Honey bees have been used as bioindicators for this purpose because they operate in very large areas in their region. The aim of this study is to investigate heavy metal pollution in honey bees and bee products in 4 different urban regions of Konya using principal component analysis (PCA) and linear discriminant analysis. In this study, when the heavy metal contents of honey bees, bee pollen, and honey samples are compared, it is seen that bees are exposed to more heavy metal contamination. Honey bees don’t reflect these amounts in the honey, and the heavy metal content in honey remains in much smaller amounts. When principal component analysis (PCA) is applied to these samples, the heavy metal variation of bees and bee pollen can be explained by three components, while the variation of the heavy metal contents of honey can be explained by four components. Linear discriminant analysis was performed to distinguish the geographic locations of the samples. According to the results of the LDA analysis for heavy metal content, the bees can be assigned to 80% and the pollen and honey to 100% of their correct geographical origin.

Chemical Properties and Biological Activity of Bee Pollen

Pollen, a remarkably versatile natural compound collected by bees for its abundant source of proteins and nutrients, represents a rich reservoir of diverse bioactive compounds with noteworthy chemical and therapeutic potential. Its extensive biological effects have been known and exploited since ancient times. Today, there is an increased interest in finding natural compounds against oxidative stress, a factor that contributes to various diseases. Recent research has unraveled a multitude of biological activities associated with bee pollen, ranging from antioxidant, anti-inflammatory, antimicrobial, and antifungal properties to potential antiviral and anticancer applications. Comprehending the extensive repertoire of biological properties across various pollen sources remains challenging. By investigating a spectrum of pollen types and their chemical composition, this review produces an updated analysis of the bioactive constituents and the therapeutic prospects they offer. This review emphasizes the necessity for further exploration and standardization of diverse pollen sources and bioactive compounds that could contribute to the development of innovative therapies.

We Built It; Did They Come? Pollinator Diversity and Community Structure in a Post-Mining Prairie Restoration Project

We Built It; Did They Come? Pollinator Diversity and Community Structure in a Post-Mining Prairie Restoration Project

Nationwide study of the triple landscape gradient across natural, agricultural and urban areas for the richness of flower-visiting insects

Studies investigating urbanisation effects on pollinator diversity have shown contrasting results, ranging from predicting urban areas as ecological sinks to possible refuges for pollinators. These divergent results may stem from the diversity of non-urban areas being compared with urban areas as well as the existence of interactions among habitats. We tested the interactive effects of urban, agricultural and semi-natural areas on the richness of flower-visiting insects at the landscape scale. Using the dataset from a citizen science programme, we investigated how the richness pattern varied (i) along the triple gradient across urban, agricultural and semi-natural areas and (ii) among the different visitor taxa. We stratified the dataset to have a balanced landscape composition and spatial distribution of sampling sites for each plant species sampled. Accounting for general sampling factors (e.g., plant species, temperature, shading, time of observation), we showed that urbanisation negatively impacted the total richness of flower visitors, especially when associated with agricultural areas. We observed maximum richness in agricultural landscapes composed of ∼30 % of semi-natural areas, thus suggesting synergistic effects between these land uses on insect richness. Our results showed contrasting richness patterns for different taxa. For bees, urban areas were less detrimental to richness than agricultural areas. By contrast, for syrphids and butterflies, richness was highest in agricultural and semi-natural areas, respectively. Our study revealed the necessity to distinguish among rural areas when studying urbanisation gradients and highlighted synergistic landscape effects that could help inform landscape planners about how to attract a diversity of flower visitors.