Overview of Bee Pollination and Its Economic Value for Crop Production

More than just sweet: current insights into microplastics in honey products and a case study of Melipona quadrifasciata honey

Honey, traditionally known as a pure and natural substance, has become an unexpected reservoir for microplastic contamination. This study consisted of an experimental investigation to assess the occurrence of microplastics in honey produced by Melipona quadrifasciata, a native bee species in Brazil. Our investigation covers eight areas (one sample per area), including built and vegetated areas located in São Paulo city, Brazil, to understand the distribution of microplastics in these environments. Honey samples (10 mL) were collected using a syringe and sent to the laboratory for further analysis. Microplastics extracted from honey samples were characterized under a stereomicroscope to determine their size, color, and morphology. Also, the polymer type was determined by FTIR analysis. All honey samples (100%) showed microplastics. The predominant particles displayed a fiber shape with a size below 299 μm and a transparent color and were primarily composed of polypropylene. Their concentrations ranged from 0.1 to 2.6 particles per mL of honey, raising concerns about their potential impact on bee populations and human consumers. This study underscores the need for further research on the sources and implications of microplastic contamination in Melipona quadrifasciata honey, shedding light on the broader issue of environmental plastic pollution and its impact on pollinators.

Common viral infections inhibit egg laying in honey bee queens and are linked to premature supersedure

With their long lives and extreme reproductive output, social insect queens have escaped the classic trade-off between fecundity and lifespan, but evidence for a trade-off between fecundity and immunity has been inconclusive. This is in part because pathogenic effects are seldom decoupled from effects of immune induction. We conducted parallel, blind virus infection experiments in the laboratory and in the field to interrogate the idea of a reproductive immunity trade-off in honey bee (Apis mellifera) queens and to better understand how these ubiquitous stressors affect honey bee queen health. We found that queens injected with infectious virus had smaller ovaries and were less likely to recommence egg-laying than controls, while queens injected with UV-inactivated virus displayed an intermediate phenotype. In the field, heavily infected queens had smaller ovaries and infection was a meaningful predictor of whether supersedure cells were observed in the colony. Immune responses in queens receiving live virus were similar to queens receiving inactivated virus, and several of the same immune proteins were negatively associated with ovary mass in the field. This work supports the hypothesized relationship between virus infection and symptoms associated with queen failure and suggests that a reproductive-immunity trade-off is partially, but not wholly responsible for these effects.

Dancing with danger-how honeybees are getting affected in the web of microplastics-a review

Anthropogenic activities have negatively impacted the ecosystem dramatically over the last few decades. The environment is becoming more contaminated with heavy metals, pesticides, and microplastics (MPs) as a result of the swift rise in industrialization and urbanisation. These contaminants are present everywhere in the ecosystem, affecting every living creature, from aquatic to terrestrial to aerial. Recently, the widespread of microplastics in the environment has raised serious concerns about the contamination of honey bees by these tiny particles of plastic. Honeybees are the major pollinators which contributes in the pollination of about 70% food that we consume. This review summarizes current research findings on the presence, uptake, and possible effects of microplastics on honey bees. Findings revealed the presence of microplastics in various honey bee matrices, such as honey, pollen, beeswax, and bee bodies, highlighting the potential routes of exposure for these vital pollinators. Additionally, evidence suggests that microplastics can accumulate in honey bee tissues (brain, midgut, Malpighian tubules, trachea, and haemolymph) potentially leading to adverse effects on honey bee health, behaviour, and colony dynamics. Additionally, MPs has a synergistic impact on immune system as well. Change in cuticle profile, reduction in body weight, and changes in eating frequency can regulate overall success rate of their survival. However, significant knowledge gaps remain regarding the long-term consequences for honey bee populations and ecosystem health, which cannot unveil the ultimate degree of future threats. Future research efforts should focus on investigating the interactions between microplastics and other stressors, such as pesticides and pathogens, and assessing the broader ecological implications of honey bee contamination with microplastics. Addressing these knowledge gaps is essential for developing effective mitigation strategies to minimize the impact of microplastics on honey bee populations and safeguarding their vital role in ecosystem functioning and food security.

Improving bee feed recipes to safeguard honeybee colonies during times of food scarcity

In beekeeping, when natural nectar or pollen sources become limited, it is crucial to provide supplemental bee feed to maintain the viability of the bee colony. This study was conducted during the autumn food shortage season, during which bees were fed with different proportions of modified bee feed. We identified an optimal bee diet by evaluating honeybee longevity, food consumption, body weight, and gut microbe distribution, with natural pollen serving as a control diet. The results indicated that bees preferred a mixture of 65% defatted soy flour, 20% corn protein powder, 13% wheat germ flour, 2% yeast powder, and a 50% sucrose solution. This bee food recipe significantly increased the longevity, feed consumption, and body weight of bees. The group fed the natural pollen diet exhibited a greater abundance of essential intestinal bacteria. The bee diets used in this study contained higher protein levels and lower concentrations of unsaturated fatty acids and vitamins than did the diets stored within the colonies. Therefore, we propose that incorporating both bee feed and natural pollen in beekeeping practices will achieve more balanced nutritional intake.

Changes in the proteome of Apis mellifera acutely exposed to sublethal dosage of glyphosate and imidacloprid

Uncontrolled use of pesticides has caused a dramatic reduction in the number of pollinators, including bees. Studies on the effects of pesticides on bees have reported effects on both metabolic and neurological levels under chronic exposure. In this study, variations in the differential expression of head and thorax-abdomen proteins in Africanized A. mellifera bees treated acutely with sublethal doses of glyphosate and imidacloprid were studied using a proteomic approach. A total of 92 proteins were detected, 49 of which were differentially expressed compared to those in the control group (47 downregulated and 2 upregulated). Protein interaction networks with differential protein expression ratios suggested that acute exposure of A. mellifera to sublethal doses of glyphosate could cause head damage, which is mainly associated with behavior and metabolism. Simultaneously, imidacloprid can cause damage associated with metabolism as well as, neuronal damage, cellular stress, and impairment of the detoxification system. Regarding the thorax-abdomen fractions, glyphosate could lead to cytoskeleton reorganization and a reduction in defense mechanisms, whereas imidacloprid could affect the coordination and impairment of the oxidative stress response.

Can Bees Detect Perfluorooctane Sulfonate (PFOS)?

The European honey bee (Apis mellifera) is an important crop pollinator threatened by multiple stressors, including exposure to contaminants. Perfluorooctane sulfonate (PFOS) is a persistent global contaminant that accumulates and biomagnifies in food chains and is detected in honey. Even sublethal exposure to PFOS is detrimental to bee health, but exposure routes are unclear and nothing is known about bee response (detection, avoidance, or attraction) to PFOS. Using Y-mazes, we studied the response of individual bees to PFOS-spiked sugar syrup at four concentrations, 0.02, 30, 61 and 103 µg L-1. Bee activity, choice behavior, and drink duration for unspiked and spiked sugar syrup was recorded for 10 min in the Y-maze system. Most bees (≥80%) tasted and then drank the sugar syrup solutions, including the PFOS-contaminated syrup. Only at 61 and 103 µg L-1 did bees significantly avoid drinking PFOS-spiked syrup, and only when given a choice with unspiked syrup. When the choice of consuming unspiked syrup was removed, the bees drank PFOS-spiked syrup at all the PFOS concentrations tested, and avoidance was not evident. Avoidance was not observed in any treatment at 0.02 or 30 µg L-1 PFOS, concentrations that are frequently reported in environmental waters in contaminated areas. These findings confirm that bees will access PFOS-contaminated resources at concentrations detrimental to the colony health, and provide evidence of potential exposure pathways that may threaten crop pollination services and also human health via food chain transfer in PFOS-contaminated areas. Environ Toxicol Chem 2024;43:1638-1647. © 2024 SETAC.

Structural and functional impacts of neonicotinoids analogues on Apis mellifera's chemosensory protein: Insights from spectroscopic and molecular modeling investigations

In the intricate web of ecological relationships, pollinators such as the Italian honeybee (Apis mellifera) play a crucial role in maintaining biodiversity and agricultural productivity. This study focuses on the interactions between three neonicotinoid compounds and the honeybee's chemosensory protein 3 (CSP3), a key player in their olfactory system. Employing advanced spectroscopic techniques and molecular modeling, we explore the binding dynamics and conformational changes in CSP3 upon exposure to these pesticides. The research reveals that all three neonicotinoids considerably quench CSP3's fluorescence through a dynamic and static mixing mechanism, indicating a strong binding affinity, predominantly driven by hydrophobic interactions. UV-visible absorption, synchronous fluorescence, and 3D fluorescence spectra support slight changes in the microenvironment around the aromatic amino acids of CSP3. Circular dichroism spectra indicate a reduction in CSP3's α-helix content, suggesting structural alterations. Molecular docking and dynamics simulations further elucidate the binding modes and stability of these interactions, highlighting the role of specific amino acids in CSP3's binding cavity. Findings provide critical insights into molecular mechanisms by which neonicotinoids may impair honeybee chemosensory function, offering implications for designing safer pesticides and understanding the broader ecological impact of these chemicals on pollinator health.

Insight into Olfactory Learning, Memory, and Mortality of Apis mellifera jemenitica after Exposure to Acetamiprid Insecticide

The honey bee, a significant crop pollinator, encounters pesticides through various routes of exposure during foraging and flower visitation. Considering the potential threat of pesticide poisoning, the indigenous Saudi bee Apis mellifera jemenitica is susceptible to the risks associated with acetamiprid, a neonicotinoid insecticide. This study investigates the acetamiprid-induced effects on the survival, olfactory learning, and memory formation of A. m. jemenitica through two exposure routes: topical application and oral ingestion. Field-realistic and serially diluted concentrations (100, 50, 25, and 10 ppm) of acetamiprid led to notable mortality at 4, 12, 24, and 48 h after treatment, with peak mortality observed at 24 h and 48 h for both exposure routes. Bee mortality was concentration-dependent, increasing with the rising concentration of acetamiprid at the tested time intervals. Food consumption following oral exposure exhibited a concentration-dependent pattern, steadily decreasing with increasing concentrations of acetamiprid. Oral exposure resulted in a substantially higher cumulative mortality (55%) compared to topical exposure (15%), indicating a significant disparity in bee mortality between the two exposure routes. The 24 h post-treatment LC50 values for acetamiprid were 160.33 and 12.76 ppm for topical application and oral ingestion, respectively. The sublethal concentrations (LC10, LC20, and LC30) of acetamiprid were 15.23, 34.18, and 61.20 ppm, respectively, following topical exposure, and 2.85, 4.77, and 6.91 ppm, respectively, following oral exposure. The sublethal concentrations of acetamiprid significantly decreased learning during the 2nd-3rd conditioning trials and impaired memory formation at 2, 12, and 24 h following both topical and oral exposure routes, compared to the control bees. Notably, the sublethal concentrations were equally effective in impairing bee learning and memory. Taken together, acetamiprid exposure adversely affected bee survival, hindered learning, and impaired the memory retention of learned tasks.

Buzzing with Intelligence: Current Issues in Apiculture and the Role of Artificial Intelligence (AI) to Tackle It

Honeybees (Apis mellifera L.) are important for agriculture and ecosystems; however, they are threatened by the changing climate. In order to adapt and respond to emerging difficulties, beekeepers require the ability to continuously monitor their beehives. To carry out this, the utilization of advanced machine learning techniques proves to be an exceptional tool. This review provides a comprehensive analysis of the available research on the different applications of artificial intelligence (AI) in beekeeping that are relevant to climate change. Presented studies have shown that AI can be used in various scientific aspects of beekeeping and can work with several data types (e.g., sound, sensor readings, images) to investigate, model, predict, and help make decisions in apiaries. Research articles related to various aspects of apiculture, e.g., managing hives, maintaining their health, detecting pests and diseases, and climate and habitat management, were analyzed. It was found that several environmental, behavioral, and physical attributes needed to be monitored in real-time to be able to understand and fully predict the state of the hives. Finally, it could be concluded that even if there is not yet a full-scale monitoring method for apiculture, the already available approaches (even with their identified shortcomings) can help maintain sustainability in the changing apiculture.

Vertical Stratification of Solitary Bees and Wasps in an Urban Forest from the Brazilian Amazon

Solitary bees and wasps that nest in cavities in tree trunks are important components of terrestrial ecosystems, providing pollination services, and in the case of wasps, the regulation of their prey populations. However, little is known about the vertical strata where bees and wasps build their nests. This is especially the case of urban forest remnants in the Amazon, which is relevant in the context of the global crisis in insect losses. We investigated the existence of vertical stratification in the nesting of solitary bees and wasps in an urban forest in Rio Branco, state of Acre, in the western Brazilian Amazon. We focused on whether wood temperature, ants, and termites are predictors of bee and wasp nesting. We sampled bee and wasp nests in the forest using trap-nests made with wooden blocks containing cavities with three different diameters for twelve months. Trap-nests were installed randomly at three heights in the forest. We collected 145 nests of 25 species, belonging to 11 genera and 6 families. A higher number of nests and species were collected in the upper stratum of the forest, strengthening the hypothesis that there is vertical stratification in the assemblage of solitary bees and wasps. Wood surface temperature and termite attacks on trap-nests were significantly different between strata, which may explain the vertical stratification of bee and wasp assemblages. Considering the importance of these insects for tropical forest ecosystems, the conservation of structurally complex and stratified forests is of paramount importance to maintain the diversity of this insect group.

Unlocking Quercetin's Neuroprotective Potential: A Focus on Bee-Collected Pollen

In the quest to evade side effects associated with synthetic drugs, mankind is continually exploring natural sources. In recent decades, neurodegenerative disorders (NDDs) have surged dramatically compared to other human diseases. Flavonoids, naturally occurring compounds, have emerged as potential preventers of NDD development. Notably, quercetin and its derivatives demonstrated excellent antioxidant properties in the fight against NDDs. Recognizing bee-collected pollen (BP) as a well-established excellent source of quercetin and its derivatives, this review seeks to consolidate available data on the prevalence of this flavonoid in BP, contingent upon its botanical and geographical origins. It aims to advocate for BP as a superb natural source of "drugs" that could serve as preventative measures against NDDs. Examination of numerous published articles, detailing the phenolic profile of BP, suggests that it can be a great source of quercetin, with an average range of up to 1000 mg/kg. In addition to quercetin, 24 derivatives (with rutin being the most predominant) have been identified. Theoretical calculations, based on the recommended dietary intake for quercetin, indicate that BP can fulfil from 0.1 to over 100 % of the requirement, depending on BP's origin and bioaccessibility/bioavailability during digestion.

Farm management and landscape context shape plant diversity at wetland edges in the Prairie Pothole Region of Canada

Evaluating the impacts of farming systems on biodiversity is increasingly important given the need to stem biodiversity loss, decrease fossil fuel dependency, and maintain ecosystem services benefiting farmers. We recorded woody and herbaceous plant species diversity, composition, and abundance in 43 wetland-adjacent prairie remnants beside crop fields managed using conventional, minimum tillage, organic, or perennial cover (wildlife-friendly) land management in the Prairie Pothole Region. We used a hierarchical framework to estimate diversity at regional and local scales (gamma, alpha), and how these are related through species turnover (beta diversity). We tested the expectation that gamma richness/evenness and beta diversity of all plants would be higher in remnants adjacent to perennial cover and organic fields than in conventional and minimum tillage fields. We expected the same findings for plants providing ecosystem services (bee-pollinated species) and disservices (introduced species). We predicted similar relative effects of land management on alpha diversity, but with the expectation that the benefits of organic farming would decrease with increasing grassland in surrounding landscapes. Gamma richness and evenness of all plants were highest for perennial cover, followed by minimum tillage, organic, and conventional sites. Bee-pollinated species followed a similar pattern for richness, but for evenness organic farming came second, after perennial cover sites, followed by minimum tillage and conventional. For introduced species, organic sites had the highest gamma richness and evenness. Grassland amount moderated the effect of land management type on all plants and bee-pollinated plant richness, but not as expected. The richness of organic sites increased with the amount of grassland in the surrounding landscape. Conversely, for conventional sites, richness increased as the amount of grassland in the landscape declined. Our results are consistent with the expectation that adopting wildlife-friendly land management practices can benefit biodiversity at regional and local scales, in particular the use of perennial cover to benefit plant diversity at regional scales. At more local extents, organic farming increased plant richness, but only when sufficient grassland was available in the surrounding landscape; organic farms also had the highest beta diversity for all plants and bee-pollinated plants. Maintaining native cover in agroecosystems, in addition to low-intensity farming practices, could sustain plant biodiversity and facilitate important ecosystem services.

Increasing temperature and time in glasshouses increases honey bee activity and affects internal brood conditions

Honey bees are globally important pollinators, key to many aspects of ecosystem function and agricultural production. However they are facing an increasing array of stress factors. These stressors include exposure to pathogens and pesticides, agricultural intensification, and changes in climate, and likely contribute to colony dysfunction and colony losses. Here we use temperature-controlled glasshouse experiments to investigate the impact of a field-realistic temperature-range on honey bee colonies, including temperatures based on projections for near-future local conditions. We show that increased temperatures have a significant impact on honey bee worker activity, with increased worker movement in and out of colonies, particularly over 30 °C. In addition, increased glasshouse temperatures led to significantly higher brood (egg, larval and pupal cells) humidity. Finally, temperature had a more severe impact at the later end of the experiment than at the start (on worker movement and brood conditions), suggesting that colonies under stress (either due to exposure to thermal stress or glasshouse confinement) have more difficulty in manging thermoregulation. These results indicate the potential impact of higher temperatures on the healthy functioning of these important pollinators.

Color-advertising strategies of invasive plants through the bee eye

Invasive plants represent a significant global challenge as they compete with native plants for limited resources such as space, nutrients and pollinators. Here, we focused on four invasive species that are widely spread in the French Pyrenees, Buddleja davidii, Reynoutria japonica, Spiraea japonica and Impatiens glandulifera, and analyzed their visual advertisement signals with respect to those displayed by their surrounding native species using a perceptual approach based on the neural mechanisms of bee vision given that bees are regular pollinators of these plants. We collected 543 spectral reflections from the 4 invasive species, and 66 native species and estimated achromatic and chromatic similarities to the bee eye. R. japonica, S. japonica and B. davidii were inconspicuous against the foliage background and could be hardly discriminated in terms of color from their surrounding native plants. These characteristics promote generalization, potentially attracting pollinators foraging on similar native species. Two morphs of I. glandulifera were both highly salient in chromatic and achromatic terms and different from their surrounding native species. This distinctive identity facilitates detection and learning in association with rich nectar. While visual signals are not the only sensory cue accounting for invasive-plant success, our study reveals new elements for understanding biological invasion processes from the perspective of pollinator perceptual processes.

Systems theory: A novel approach for understanding how stressors affect honey bee health 'all at once'

A new study showcases the usefulness of systems theory and network analyses for understanding how dozens of stressors can act concomitantly to affect managed honey bee health. Interestingly, the most influential stressors are not those currently being addressed by beekeepers.

A colony health and economic comparison of Varroa-resistant Varroa destructor (Mesostigmata: Varroidae) and commercial honey bees (Hymenoptera: Apidae)

Honey bees (Apis mellifera L.) are the premier agricultural pollinators with direct ecological value and are key to some agro-economies. Major factors have negatively impacted honey bee health in the past 2 decades with Varroa (Varroa destructor Anderson and Trueman) infestation rising as a principal predictor of colony mortality. A key strategy deployed in Varroa management is breeding for resistant honey bee populations that can maintain comparable levels of productivity as nonresistant populations. In this study, we examine one such population, Hilo honey bees, within the context of a common garden contrast with a commercial population in a stationary honey production operation. We compare colony survival, health, yield, and profit outcomes to show how this specific breeding population retains a profit value in honey production operations while maintaining higher survival and lower Varroa infestation levels than the commercial population. This information can be used by commercial beekeepers to make best management practice decisions and inspire further work examining what trade-offs, if any, are present in this Varroa-resistant population.

Honey bee stressor networks are complex and dependent on crop and region

Honey bees play a major role in crop pollination but have experienced declining health throughout most of the globe. Despite decades of research on key honey bee stressors (e.g., parasitic Varroa destructor mites and viruses), researchers cannot fully explain or predict colony mortality, potentially because it is caused by exposure to multiple interacting stressors in the field. Understanding which honey bee stressors co-occur and have the potential to interact is therefore of profound importance. Here, we used the emerging field of systems theory to characterize the stressor networks found in honey bee colonies after they were placed in fields containing economically valuable crops across Canada. Honey bee stressor networks were often highly complex, with hundreds of potential interactions between stressors. Their placement in crops for the pollination season generally exposed colonies to more complex stressor networks, with an average of 23 stressors and 307 interactions. We discovered that the most influential stressors in a network-those that substantively impacted network architecture-are not currently addressed by beekeepers. Finally, the stressor networks showed substantial divergence among crop systems from different regions, which is consistent with the knowledge that some crops (e.g., highbush blueberry) are traditionally riskier to honey bees than others. Our approach sheds light on the stressor networks that honey bees encounter in the field and underscores the importance of considering interactions among stressors. Clearly, addressing and managing these issues will require solutions that are tailored to specific crops and regions and their associated stressor networks.

Biotic and abiotic stresses on honeybee health

Honeybees are the most critical pollinators providing key ecosystem services that underpin crop production and sustainable agriculture. Amidst a backdrop of rapid global change, this eusocial insect encounters a succession of stressors during nesting, foraging, and pollination. Ectoparasitic mites, together with vectored viruses, have been recognized as central biotic threats to honeybee health, while the spread of invasive giant hornets and small hive beetles also increasingly threatens colonies worldwide. Cocktails of agrochemicals, including acaricides used for mite treatment, and other pollutants of the environment have been widely documented to affect bee health in various ways. Additionally, expanding urbanization, climate change, and agricultural intensification often result in the destruction or fragmentation of flower-rich bee habitats. The anthropogenic pressures exerted by beekeeping management practices affect the natural selection and evolution of honeybees, and colony translocations facilitate alien species invasion and disease transmission. In this review, the multiple biotic and abiotic threats and their interactions that potentially undermine bee colony health are discussed, while taking into consideration the sensitivity, large foraging area, dense network among related nestmates, and social behaviors of honeybees.

Current honey bee stressor investigations and mitigation methods in the United States and Canada

Honey bees are the most important managed insect pollinators in the US and Canadian crop systems. However, the annual mortality of colonies in the past 15 years has been consistently higher than historical records. Because they are eusocial generalist pollinators and amenable to management, honey bees provide a unique opportunity to investigate a wide range of questions at molecular, organismal, and ecological scales. Here, the American Association of Professional Apiculturists (AAPA) and the Canadian Association of Professional Apiculturists (CAPA) created 2 collections of articles featuring investigations on micro and macro aspects of honey bee health, sociobiology, and management showcasing new applied research from diverse groups studying honey bees (Apis mellifera) in the United States and Canada. Research presented in this special issue includes examinations of abiotic and biotic stressors of honey bees, and evaluations and introductions of various stress mitigation measures that may be valuable to both scientists and the beekeeping community. These investigations from throughout the United States and Canada showcase the wide breadth of current work done and point out areas that need further research.

Discussion: Harnessing microbiome-mediated adaptations in insect pollinators to mitigate climate change impact on crop pollination

Insect pollinators, vital for agriculture and biodiversity, face escalating threats from climate change. We argue and explore the pivotal role of the microbiomes in shaping adaptations of insect pollinator resilience amid climate-induced challenges (climate change and habitat alteration). Examining diverse taxonomic groups, we unravel the interplay between insect physiology, microbiomes, and adaptive mechanisms. Climate-driven alterations in microbiomes impact insect health, behavior, and plant interactions, posing significant effects on agricultural ecosystems. We propose harnessing microbiome-mediated adaptations as a strategic approach to mitigate climate change impacts on crop pollination. Insights into insect-pollinator microbiomes offer transformative avenues for sustainable agriculture, including probiotic interventions (use of EM PROBIOTIC) and microbiome engineering (such as engineering gut bacteria) to induce immune responses and enhanced pollination services. Integrating microbiome insights into conservation practices elucidates strategies for preserving pollinator habitats, optimizing agricultural landscapes, and developing policies to safeguard pollinator health in the face of environmental changes. Finally, we stress interdisciplinary collaboration and the urgency of understanding pollinator microbiome dynamics under climate change in future research.

Decision support model to assess pesticide safeness toward environment

For farmers around the world to protect crops from disturbing pests, it is common to use pesticides to ward off the growth of pests or even eliminate them. Even though pesticides are seen as a good thing for protecting crops, there is one thing that mustn't be forgotten the origin of the pesticide itself is a toxin compound that is dangerous if used irresponsibly. The main concern of this study is excessive use of pesticides may cause serious consequences to the ecosystem and environment through the accumulation of pesticide residue by irresponsible farmers. To minimize the effects of pesticide residues, the selection of the type of pesticide needs to be considered which type may not be harmful to the environment's health even though accumulation happens. Therefore, in this study, a fuzzy-based computational model assessor was built to measure the safety level of pesticides toward the environment. The fuzzy model was created with consideration of several parameters related to pesticide behaviors, its effects on beneficial organisms, and its persistence in the environment. The method used for this study includes literature reviewing, fuzzification, statistical approach, expert knowledge sharing, and quantitative analysis. The model created in this study can assist in a more accurate and realistic method of selecting better pesticide options that will be used by farmers. To ensure the validity of the model, verifying and validating the formula and pesticide result assessment were done with related literature articles. In this study, from 10 types of pesticides used as a sample, dodine, and iprodione pesticides are the best option for protecting crops with a safety level of 7.36, and abamectin, dimethoate, chorpyrifos, and methidathion are not safe options for farming use because of its potential of harming the environment.

Effects of study design parameters on estimates of bee abundance and richness in agroecosystems: a meta-analysis

Pollinators are critical for agricultural production and food security, leading to many ongoing surveys of pollinators (especially bees) in crop and adjacent landscapes. These surveys have become increasingly important to better understand the community of potential pollinators, quantify relative insect abundance, and secure crop ecosystem services. However, as some bee populations are declining, there is a need to align and improve bee survey efforts, so that they can best meet research and conservation goals, particularly in light of the logistical and financial constraints of conducting such studies. Here, we mined the existing literature on bee surveys in or around agricultural lands to better understand how sampling methods can be optimized to maximize estimates of 2 key measures of bee communities (abundance and richness). After reviewing 72 papers spanning 20 yr of publication, we found that study duration, number of sites, sampling time, and sampling method most significantly influenced abundance, while the number of trips per year and collection method significantly influenced richness. Our analysis helps to derive thresholds, priorities, and recommendations that can be applied to future studies describing bee communities in agroecosystems.

Advances and knowledge gaps on climate change impacts on honey bees and beekeeping: A systematic review

The Western honey bee Apis mellifera is a managed species that provides diverse hive products and contributing to wild plant pollination, as well as being a critical component of crop pollination systems worldwide. High mortality rates have been reported in different continents attributed to different factors, including pesticides, pests, diseases, and lack of floral resources. Furthermore, climate change has been identified as a potential driver negatively impacting pollinators, but it is still unclear how it could affect honey bee populations. In this context, we carried out a systematic review to synthesize the effects of climate change on honey bees and beekeeping activities. A total of 90 articles were identified, providing insight into potential impacts (negative, neutral, and positive) on honey bees and beekeeping. Interest in climate change's impact on honey bees has increased in the last decade, with studies mainly focusing on honey bee individuals, using empirical and experimental approaches, and performed at short-spatial (<10 km) and temporal (<5 years) scales. Moreover, environmental analyses were mainly based on short-term data (weather) and concentrated on only a few countries. Environmental variables such as temperature, precipitation, and wind were widely studied and had generalized negative effects on different biological and ecological aspects of honey bees. Food reserves, plant-pollinator networks, mortality, gene expression, and metabolism were negatively impacted. Knowledge gaps included a lack of studies at the apiary and beekeeper level, a limited number of predictive and perception studies, poor representation of large-spatial and mid-term scales, a lack of climate analysis, and a poor understanding of the potential impacts of pests and diseases. Finally, climate change's impacts on global beekeeping are still an emergent issue. This is mainly due to their diverse effects on honey bees and the potential necessity of implementing adaptation measures to sustain this activity under complex environmental scenarios.

Glyphosate exposure affected longevity-related pathways and reduced survival in asian honey bees (Apis cerana)

Glyphosate (N-(phosphonomethyl)glycine, GLY) ranks among the most extensively used and effective herbicides globally. However, excessive GLY utilization poses a substantial threat to the survival of honey bees (Apis cerana). Here we monitored the survival status of A. cerana treated with GLY, and conducted transcriptome sequencing of the bee gut and head to further explore potential GLY influences at the molecular level. We observed that the mortality rate of bees increased as GLY concentration escalated. Pivotal pathways emerged in response to the GLY treatment, with a substantial number of differentially expressed genes enriched in the longevity regulating pathway - multiple species. This strongly suggested that GLY may influence the physiological behavior of bees by impacting this particular pathway. Moreover, our analysis revealed a notable reduction in the enzymatic activities of CYP450 and AChE in both the bee head and intestines of when exposed to GLY. Conversely, the enzymatic activity of superoxide dismutase (SOD) in the head remained unaffected, whereas in the intestines, it exhibited a significant increase. Additionally, prophenol oxidase (PPO) and glutathione-S-transferases (GSTs) displayed contrasting trends in enzymatic activity in both organs. This study offers valuable insights into how GLY impacted the survival of A. cerana.

Distinct fungal microbiomes of two Thai commercial stingless bee species, Lepidotrigona terminata and Tetragonula pagdeni suggest a possible niche separation in a shared habitat

Stingless bees, a social corbiculate bee member, play a crucial role in providing pollination services. Despite their importance, the structure of their microbiome, particularly the fungal communities, remains poorly understood. This study presents an initial characterization of the fungal community associated with two Thai commercial stingless bee species, Lepidotrigona terminata (Smith) and Tetragonula pagdeni (Schwarz) from Chiang Mai, Thailand. Utilizing ITS amplicon sequencing, we identified distinct fungal microbiomes in these two species. Notably, fungi from the phyla Ascomycota, Basidiomycota, Mucoromycota, Mortierellomycota, and Rozellomycota were present. The most dominant genera, which varied significantly between species, included Candida and Starmerella. Additionally, several key enzymes associated with energy metabolism, structural strength, and host defense reactions, such as adenosine triphosphatase, alcohol dehydrogenase, β-glucosidase, chitinase, and peptidylprolyl isomerase, were predicted. Our findings not only augment the limited knowledge of the fungal microbiome in Thai commercial stingless bees but also provide insights for their sustainable management through understanding their microbiome.

Seasonal screening of pesticide residues in beehive products collected from different districts in Egypt

Pesticides are of immense importance in agriculture, but they might contaminate bees' products. In this study, samples of honey, pollen, and beeswax were collected, seasonally, from apiaries in Toshka (Aswan), El-Noubariya (El-Beheira), and Ismailia (Ismailia) cities in Egypt. The pesticide residues were analyzed using the GC-MS after being extracted and cleaned using the QuEChERS method. Results showed that samples from El-Noubariya had great content of residues followed by Ismailia, and finally Toshka. Samples collected during fall and winter had the highest pesticide residue contents. Specifically, the phenylconazole fungicide group was repeatedly detected in all the examined samples along with organophosphate insecticides. Beeswax samples had the greatest amounts of pesticide residues followed by pollen and then honey samples. Chlorpyrifos (0.07-39.16 ng/g) and profenofos (1.94-17.00 ng/g) were detected in honey samples and their products. Pyriproxyfen (57.12 ng/g) and chlorpyrifos-methyl (39.16 ng/g) were detected in great amounts in beeswax samples from Ismailia and El-Noubariya, respectively. Yet, according to health hazard and quotient studies, the amounts of pesticides detected in honey do not pose any health threats to humans.

Metagenomic analysis of the honey bee queen microbiome reveals low bacterial diversity and Caudoviricetes phages

In eusocial insects, the health of the queens-the colony founders and sole reproductive females-is a primary determinant for colony success. Queen failure in the honey bee Apis mellifera, for example, is a major concern of beekeepers who annually suffer colony losses, necessitating a greater knowledge of queen health. Several studies on the microbiome of honey bees have characterized its diversity and shown its importance for the health of worker bees, the female non-reproductive caste. However, the microbiome of workers differs from that of queens, which, in comparison, is still poorly studied. Thus, direct investigations of the queen microbiome are required to understand colony-level microbiome assembly, functional roles, and evolution. Here, we used metagenomics to comprehensively characterize the honey bee queen microbiome. Comparing samples from different geographic locations and breeder sources, we show that the microbiome of queens is mostly shaped by the environment experienced since early life and is predicted to play roles in the breakdown of the diet and protection from pathogens and xenobiotics. We also reveal that the microbiome of queens comprises only four candidate core bacterial species, Apilactobacillus kunkeei, Lactobacillus apis, Bombella apis, and Commensalibacter sp. Interestingly, in addition to bacteria, we show that bacteriophages infect the queen microbiome, for which Lactobacillaceae are predicted to be the main reservoirs. Together, our results provide the basis to understand the honey bee colony microbiome assemblage, can guide improvements in queen-rearing processes, and highlight the importance of considering bacteriophages for queen microbiome health and microbiome homeostasis in eusocial insects.IMPORTANCEThe queen caste plays a central role in colony success in eusocial insects, as queens lay eggs and regulate colony behavior and development. Queen failure can cause colonies to collapse, which is one of the major concerns of beekeepers. Thus, understanding the biology behind the queen's health is a pressing issue. Previous studies have shown that the bee microbiome plays an important role in worker bee health, but little is known about the queen microbiome and its function in vivo. Here, we characterized the queen microbiome, identifying for the first time the present species and their putative functions. We show that the queen microbiome has predicted nutritional and protective roles in queen association and comprises only four consistently present bacterial species. Additionally, we bring to attention the spread of phages in the queen microbiome, which increased in abundance in failing queens and may impact the fate of the colony.

Impact of Brood Cell Cocoons on Metal Accumulation and CYP450 Detoxification Gene Expression in Apis cerana cerana

Honey bees play a critical role as pollinators. However, their reproduction success and survival face severe threats due to the deterioration of their living environment. Notably, environmental conditions during their preimaginal stage inside brood cells can influence their immune capabilities and overall health after emergence. During the in-cell developmental stage, workers are in close contact with cocoons, which can become a source of stress due to accumulated metals. To investigate this potential threat, experiments were conducted to examine the impact of cocoons in brood cells used to rear different generations on the metal content and detoxification gene expression levels in Apis cerana cerana. Our findings indicated significant differences in the layers, weight, base thickness, and metal contents like Cr, Cd, Pb, Mn, Ni, and As of cocoons in multi-generation brood cells compared to single-generation brood cells. These increases led to significant elevations in metal levels and upregulations of the four CYP450 detoxification genes in both six-day-old larvae and newly emerged workers. In conclusion, this study highlights the negative impact of cocoons in multi-generation brood cells on bee health and provides evidence supporting the development of rational apiculture management strategies for ecosystem stability.

Alcohol extract of the gypsy mushroom (Cortinarius caperatus) inhibits the development of Deformed wing virus infection in western honey bee (Apis mellifera)

Deformed wing virus (DWV) transmitted by the parasitic mite Varroa destructor is one of the most significant factors contributing to massive losses of managed colonies of western honey bee (Apis mellifera) subspecies of European origin reported worldwide in recent decades. Despite this fact, no antiviral treatment against honey bee viruses is currently available for practical applications and the level of viral infection can only be controlled indirectly by reducing the number of Varroa mites in honey bee colonies. In this study, we investigated the antiviral potential of the gypsy mushroom (Cortinarius caperatus) to reduce DWV infection in honey bees. Our results indicate that the alcohol extract of C. caperatus prevented the development of DWV infection in cage experiments as well as after direct application to honey bee colonies in a field experiment. The applied doses did not shorten the lifespan of honey bees. The reduced levels of DWV in C. caperatus-treated honey bees in cage experiments were accompanied by significant changes in the gene expression of Tep7, Bap1, and Vago. The C. caperatus treatment was not effective against the trypanosomatid Lotmaria passim. No residues of C.caperatus were found in honey harvested in the spring from colonies supplemented with the mushroom extract for their winter feeding. These findings suggest that C. caperatus alcohol extract could be a potential natural remedy to treat DWV infection in honey bees.

Health status of honeybee colonies (Apis mellifera) and disease-associated risk factors in different agroecological zones of Southwest Ethiopia

A cross-sectional study design was conducted in different agroecological zones of southwest Ethiopia from October 2019 to October 2021. The study aimed to determine the prevalence and associated risk factors for honeybee diseases and pests, as well as the impact of these issues on honeybee colonies and their products. To identify potential risk factors for honeybee disease and pests, a multivariate random effects logistic regression analysis was used. Adult honeybee and brood samples from a total of 384 honeybee colonies were collected and tested using standard laboratory diagnostic methods. The highest prevalence (55.8%) of ants was recorded, followed by wax moths (22.5%) and hive beetles (23.3%). In the current study, the main honeybee diseases observed in the study areas were varroosis (36.5%), bee lice (5.2%), nosemosis (39.6%), amoeba (56%), and chalkbrood (4.5%). However, tracheal mites, sachbrood, and American and European foul brood, were not detected. The agroecological zone (OR = 5.2, 95% CI: 1.75-14.85), type of hive (OR = 2.9, 95% CI: 1.17-17.03), management system (OR = 4.3, 95% CI: 1.23-14.70), and the management of the colony (OR = 3.5, 95% CI: 1.31-9.14) were identified as risk factors for varroosis in these areas. The occurrence of nosemosis in colonies was also influenced by the agroecological zone (OR = 12.2, 95% CI: 3.06-48.54) and colony management (OR = 3.4, 95% CI: 1.59-7.23). The agroecological zone (OR = 10.5, 95% CI: 12.76-22.63) and hive type (OR = 3.0, 95% CI: 1.39-6.36) were the primary risk factors for the occurrence of amoeba in honeybee colonies. However, the occurrence of bee lice (OR = 34.7, 95% CI: 3.96-104.93) and chalkbrood (OR = 4.8, 95% CI: 1.44-13.16) in honeybee colonies was only influenced by the agroecological zone in the study areas. This study demonstrated that losses in honey production in the area are significantly attributed to honeybee disease and pests. Therefore, it is essential to increase public awareness of how honeybee diseases and pests affect honey production and to develop and implement appropriate control measures for these diseases and pests. Furthermore, more studies should be conducted to characterize and isolate other causes of honeybee diseases and pests in various locations.

A scoping review on the effects of Varroa mite (Varroa destructor) on global honey bee decline

Arguably the most ecologically and economically valuable pollinators worldwide, honey bees play a significant role in food production and enrich biodiversity through pollination. Varroa destructor is an invasive ectoparasitic mite that attacks and feeds on European honey bee, Apis mellifera. Because literature on the effectiveness and sustainability of various treatment modalities available for Varroa mite control in honey bee colonies are scattered, this scoping review was conducted to serve as a guiding document with a focus on: (1) identifying the detrimental impact Varroa mites have on the European honey bee; (2) determining current methods for Varroa mite control and their limitations; (3) examining current market landscape and key players in the pesticide market; and (4) identifying opportunities for more sustainable Varroa mite control methods. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, 397 articles published between 1998 and 2022 were screened; of which 65 articles were retained using inclusion/exclusion criteria, which were systematically analyzed in-depth, information extracted, and included in this scoping review. The results suggest that Varroa mites are one of the predominant causes of global honey bee decline as they lack natural resistance to Varroa mites, thereby negatively affecting honey bee reproduction and immunity, killing broods, and transmitting pathogenic viruses to colonies. Further, our findings suggest that: apiarists have many options for Varroa control, but no method has proven to be effective, safe and nonpersistent in the environment; adoption of nano-pesticides and development of sustainable alternatives to traditional pesticides are key drivers for growing pesticide market; and nano-pesticides may have potential to serve as an effective, safe and non-ecopersistent pesticide for Varroa mite and associated virus control. In conclusion, this review highlights an unmet need for effective and sustainable control strategies and tools for Varroa mite and virus control.

Olfactory Learning Behavior and Mortality of the Honey Bee Apis mellifera jemenitica in Response to Pyrethroid Insecticide (Deltamethrin)

Honey bees are constantly threatened due to the wide use of pesticides. This study presents the effects of deltamethrin on the mortality, olfactory learning, and memory formation of the native Saudi bee Apis mellifera jemenitica. Topical and oral application of realistic field and serial dilutions of deltamethrin (250, 125, 62.5, and 25 ppm) caused significant mortality at 4, 12, 24, and 48 h posttreatment. Bee mortality increased with the increasing concentration of insecticide at all tested posttreatment times. Highest mortality was observed at 24 h and 48 h after both exposure routes. Food consumption gradually decreased with increasing concentration of deltamethrin during oral exposure. The LC50 of deltamethrin was determined at 12, 24, and 48 h for topical (86.28 ppm, 36.16 ppm, and 29.19 ppm, respectively) and oral (35.77 ppm, 32.53 ppm, and 30.78 ppm, respectively) exposure. Oral exposure led to significantly higher bee mortality than topical exposure of deltamethrin at 4 h and 12 h, but both exposure routes were equally toxic to bees at 24 h and 48 h. The sublethal concentrations (LC10, LC20, and LC30) of deltamethrin significantly impaired the learning during conditioning trials, as well as the memory formation of bees at 2, 12, and 24 h after topical and oral exposure. Thus, deltamethrin inhibits learning, and bees were unable to memorize the learned task.

Occurrence of chlorpyrifos and organochlorine pesticides in a native bumblebee (Bombus pauloensis) living under different land uses in the southeastern Pampas, Argentina

Pollinators such as Apidae bees are vital for ecosystems and food security. Unfortunately, their populations have declined due to several factors including pesticide use. Among them, the organophosphate insecticide chlorpyrifos, poses a global threat, while legacy compounds like organochlorine pesticides (OCPs) easily bioaccumulate, increasing the concern. Bombus pauloensis, a widely distributed native bee in Argentina, is used for commercial pollination; however, information regarding their health status is scarce. This study assessed chlorpyrifos and OCP levels in B. pauloensis (workers and males) and related environmental matrices living from three different land uses schemes, by means of GC-ECD and GC-MS. The ornamental horticulture field (OP) showed the highest total pesticide concentrations in workers (13.1 ng/g), flowers and soils, whereas the organic agriculture field (OA) exhibited the lowest. Chlorpyrifos was the most abundant compound, accounting for at least 20 % of pesticide load across all matrices. The food production horticulture field (FH) had the highest chlorpyrifos concentration in workers, males and soils (5.0, 4.4 and 3.3 ng/g, respectively), suggesting a local greater usage, whereas OA showed the lowest. Regarding OCPs groups, Drins and DDTs were predominant in most matrices, with FH males registering the highest levels (4.0 and 2.5 ng/g, respectively), closely followed by OP. However, metabolites' contribution indicated historical use and atmospheric inputs in all sites. Multivariate analyses confirmed the significance of site and bumblebee sex to explain pesticide composition. Males from all sites exhibited higher chlorpyrifos levels than workers and this trend was similar for some OCP groups. Overall, OA differed from FH and OP, indicating a correlation between production modes and pesticide profiles. This study demonstrates the value of B. pauloensis as a pesticide biomonitor but also offers insights into its populations' health in the area. In this sense, this information could be useful towards the preservation of this crucial pollinator.

Effects of the insecticide imidacloprid on the post-embryonic development of the honey bee Apis mellifera (Hymenoptera: Apidae)

The widespread use of pesticides in agriculture has been linked to declines in bee populations worldwide. Imidacloprid is a widely used systemic insecticide that can be found in the pollen and nectar of plants and has the potential to negatively impact the development of bee larvae. We investigated the effects of oral exposure to a realistic field concentration (20.5 ng g-1) of imidacloprid on the midgut and fat body of Apis mellifera worker larvae. Our results showed that larvae exposed to imidacloprid exhibited changes in the midgut epithelium, including disorganization of the brush border, nuclear chromatin condensation, cytoplasm vacuolization, and release of cell fragments indication cell death. Additionally, histochemical analysis revealed that the midgut brush border glycocalyx was disorganized in exposed larvae. The fat body cells of imidacloprid-exposed larvae had a decrease in the size of lipid droplets from 50 to 8 μm and increase of 100 % of protein content, suggesting possible responses to the stress caused by the insecticide. However, the expression of de cdc20 gene, which plays a role in cell proliferation, was not affected in the midgut and fat body of treated larvae. These results suggest that imidacloprid negatively affects non-target organs during the larval development of A. mellifera potentially impacting this important pollinator species.

Chemical Profile of Essential Oils of Selected Lamiaceae Plants and In Vitro Activity for Varroosis Control in Honeybees (Apis mellifera)

The most significant ectoparasitic mite of honeybees, Varroa destructor, has a detrimental effect on bee health and honey output. The principal strategy used by the control programs is the application of synthetic acaricides. All of this has resulted in drug resistance, which is now a major worry for beekeeping. As a result, research on alternate products and techniques for mite management is now required. The aim of this study was to determine whether essential oils (EOs) extracted from botanical species of Lamiacae, typical of the Calabria region of Southern Italy, could reduce the population of the mite V. destructor. Among the best-known genera of the Lamiaceae family are oregano, rosemary and thyme, whose EOs were employed in this study. By steam distillation, the EOs were extracted from Origanum vulgare subsp. viridulum (Martrin-Donos) Nyman, Thymus capitatus Hoffmanns. and Link, Thymus longicaulis C.Presl and Salvia rosmarinus Schleid. plant species harvested directly on the Calabrian territory in their balsamic time. Each EO went to the test in vitro (contact toxicity) against V. destructor. Fifty adult female mites, five for each EO and the positive and negative control, were used in each experimental replicate. The positive controls comprised five individuals treated to Amitraz dilute in acetone, and the negative controls included five individuals exposed to acetone alone. To create the working solution to be tested (50 μL/tube), the EOs were diluted (0.5 mg/mL, 1 mg/mL, 2 mg/mL and 4 mg/mL) in HPLC-grade acetone. After 1 h of exposure, mite mortality was manually assessed. Origanum vulgare subsp. viridulum, Thymus capitatus and Thymus longicaulis were the EOs with the highest levels of efficiency at 2 mg/mL, neutralizing (dead + inactivated), 94%, 92% and 94% of parasites, respectively. Salvia rosmarinus EO gave a lower efficacy, resulting in a percentage of 38%. Interestingly, no adverse effects were highlighted in toxicity tests on honeybees. These results show that these OEs of the Lamiaceae family have antiparasitic action on V. destructor. Therefore, they could be used, individually or combined, to exploit the synergistic effect for a more sustainable control of this parasite mite in honeybee farms.

Applications of Romanian Propolis in Phyto-Inhibitory Activity and Antimicrobial Protection: A Comparative Study

Propolis use in medicine, pharmaceutical, cosmetic, and food industries is well known. This study aimed to investigate propolis' phyto-inhibitory and antimicrobial potential. Nine propolis samples obtained from distinct Romanian regions and characterized in terms of physical-chemical parameters, phenols and flavonoid contents, and antioxidant properties were prepared as dry propolis and aqueous extracts. The phyto-inhibitory effect was comparatively tested on different cereals: hexaploid bread wheat (Triticum aestivum), maize (Zea mays L.), oats (Avena sativa L.), and barley (Hordeum vulgare L.), while their in vitro antimicrobial activity was evaluated against bacterial and fungal strains specific to cereals: Bacillus subtilis, B. cereus, Proteus mirabilis, Fusarium oxysporum, Penicillium chrysogenum, and Aspergillus niger. All propolis samples showed a phyto-inhibitory effect on the cereals, the most pronounced being corn and oats. Propolis powder samples displayed a lower phyto-inhibitory activity than propolis extracts. Also, all tested products showed inhibitory efficacy against both bacteria and fungi. Furthermore, principal component analysis showed differences between the samples' phyto-inhibitory and antimicrobial properties depending on the geographical origin. Positive correlations were found between the polyphenols, flavonoid content, and antioxidant activity, respectively. These data support propolis' phyto-pharmaceutical potential related to its use in plant crop management as an alternative in ecological agriculture.

Processing of the 3C/D Region of the Deformed Wing Virus (DWV)

The deformed wing virus (DWV) belongs to the genus Iflavirus and the family Iflaviridae within the order Picornavirales. It is an important pathogen of the Western honey bee, Apis mellifera, causing major losses among honey bee colonies in association with the ectoparasitic mite Varroa destructor. Although DWV is one of the best-studied insect viruses, the mechanisms of viral replication and polyprotein processing have been poorly studied in the past. We investigated the processing of the protease-polymerase region at the C-terminus of the polyprotein in more detail using recombinant expression, novel serological reagents, and virus clone mutagenesis. Edman degradation of purified maturated polypeptides uncovered the C- and N-termini of the mature 3C-like (3CL) protease and RNA-dependent RNA polymerase (3DL, RdRp), respectively. Autocatalytic processing of the recombinant DWV 3CL protease occurred at P1 Q2118 and P1' G2119 (KPQ/GST) as well as P1 Q2393 and P1' S2394 (HAQ/SPS) cleavage sites. New monoclonal antibodies (Mab) detected the mature 3CL protease with an apparent molecular mass of 32 kDa, mature 3DL with an apparent molecular mass of 55 kDa as well as a dominant 3CDL precursor of 90 kDa in DWV infected honey bee pupae. The observed pattern corresponds well to data obtained via recombinant expression and N-terminal sequencing. Finally, we were able to show that 3CL protease activity and availability of the specific protease cleavage sites are essential for viral replication, protein synthesis, and establishment of infection using our molecular clone of DWV-A.

Isolation and Identification of Microorganisms and Antibiotic Resistance Microorganisms from Beehives Located in Palm, Corn and Longan Plantations, Thailand

This study aims to determine the prevalence of microorganisms and antibiotic-resistant microorganisms in beehives located on different plantations in Thailand. Seventeen swabs immersed in transport media were utilized for samples from different zones within beehives. Traditional microbial culture-based methods, biochemical tests, MALDI-TOF MS (VITEK® MS, bioMerieux, Marcy-l'Étoile, France), and antibiotic drug susceptibility (disk-diffusion) tests were used to detect microorganism and antimicrobial resistance bacteria. The results from 16 beehive swabs found Gram-positive bacteria at 59.5%, Gram-negative bacteria at 35.1%, and fungi (yeast) at 5.4%. These organisms are classified as 11, 11, and 2 types of Gram-positive bacteria, Gram-negative bacteria, and fungi (yeast), respectively. Furthermore, no organism showed resistance to vancomycin or cefoxitin for antibiotic drug susceptibility testing. In contrast, all Acinetobacter spp. were susceptible to ciprofloxacin, levofloxacin, ceftazidime, cefotaxime, imipenem, and meropenem, except for Acinetobacter schindleri, which was resistant to ceftazidime and cefotaxime. For other organisms, due to the limitations of tests to identify some environmental microbial species, the antimicrobial susceptibility test results cannot be interpreted as resistant or susceptible to the drug for these organisms. The study's findings will support prevention, healthcare services, and public health systems.

Identification of peptides from honeybee gut symbionts as potential antimicrobial agents against Melissococcus plutonius

Eusocial pollinators are crucial elements in global agriculture. The honeybees and bumblebees are associated with a simple yet host-restricted gut community, which protect the hosts against pathogen infections. Recent genome mining has led to the discovery of biosynthesis pathways of bioactive natural products mediating microbe-microbe interactions from the gut microbiota. Here, we investigate the diversity of biosynthetic gene clusters in the bee gut microbiota by analyzing 477 genomes from cultivated bacteria and metagenome-assembled genomes. We identify 744 biosynthetic gene clusters (BGCs) covering multiple chemical classes. While gene clusters for the post-translationally modified peptides are widely distributed in the bee guts, the distribution of the BGC classes varies significantly in different bee species among geographic locations, which is attributed to the strain-level variation of bee gut members in the chemical repertoire. Interestingly, we find that Gilliamella strains possessing a thiopeptide-like BGC show potent activity against the pathogenic Melissococcus plutonius. The spectrometry-guided genome mining reveals a RiPP-encoding BGC from Gilliamella with a 10 amino acid-long core peptide exhibiting antibacterial potentials. This study illustrates the widespread small-molecule-encoding BGCs in the bee gut symbionts and provides insights into the bacteria-derived natural products as potential antimicrobial agents against pathogenic infections.

Effects of Plant-Based Supplement on Oxidative Stress of Honey Bees (Apis mellifera) Infected with Nosema ceranae

One of the most important approaches in the prevention and treatment of nosemosis is the use of herbal preparations as food supplements for bees. Therefore, the aim of this study was to investigate the effects of a plant-based supplement branded as "B+" on honeybees in a laboratory experiment. Four experimental groups were established: treated group (T), N. ceranae-infected and treated group (IT), N. ceranae-infected group (I) and non-infected group (NI). Survival, N. ceranae spore load and oxidative stress parameters together with expression levels of antioxidant enzyme genes and vitellogenin gene were monitored. The mortality in the T, IT and NI groups was significantly (p < 0.001) lower than in than in the I group. Within Nosema-infected groups, the IT group had a significantly lower (p < 0.001) number of N. ceranae spores than the I group. In addition, expression levels of genes for antioxidant enzymes were lower (p < 0.001) in the IT group compared to the I group. The concentration of malondialdehyde and the activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione S-transferase) were significantly lower (p < 0.001) in the IT group compared to the I group. No negative effects of the tested supplement were observed. All these findings indicate that the tested supplement exerted beneficial effects manifested in better bee survival, reduced N. ceranae spore number and reduced oxidative stress of bees (lower expression of genes for antioxidant enzymes and oxidative stress parameters).

Wild bee and pollen microbiomes across an urban-rural divide

Wild pollinators and their microbiota are sensitive to land use changes from anthropogenic activities that disrupt landscape and environmental features. As urbanization and agriculture affect bee habitats, human-led disturbances are driving changes in bee microbiomes, potentially leading to dysbiosis detrimental to bee fitness. This study examines the bacterial, fungal, and plant compositions of the small carpenter bee, Ceratina calcarata, and its pollen provisions across an urban-rural divide. We performed metabarcoding of C. calcarata and provisions in Toronto by targeting the 16S rRNA, ITS, and rbcL regions. Despite similar plant composition and diversity across bees and their provisions, there was a greater microbial diversity in pollen provisions than in bees. By characterizing the differences in land use, climate, and pesticide residues that differentiate urban and rural landscapes, we find that urban areas support elevated levels of microbial diversity and more complex networks between microbes and plants than rural areas. However, urban areas may lead to lower relative abundances of known beneficial symbionts and increased levels of pathogens, such as Ascosphaera and Alternaria fungi. Further, rural pollen provisions indicate elevated pesticide residues that may dysregulate symbiosis. As anthropogenic activities continue to alter land use, ever changing environments threaten microbiota crucial in maintaining bee health.

Review: the risks of spray adjuvants to honey bees

Pesticide applications are often made as tank mixes containing multiple pesticide products and may include spray adjuvants to enhance pesticidal activities. The primary aim of adjuvant products is to increase the spreading and sticking of spray droplets and to increase the penetration of active ingredients through the cuticles of leaves or targeted pests, which can reduce the amount of active ingredient needed for effective pest control. Adjuvants are made up of compounds drawn from the "inert ingredient" list maintained by EPA but are identified as "principal functioning agents" when used in adjuvant products. These inert compounds do not undergo the same testing and risk assessment process that is required of pesticide active ingredients and generally have no mitigation measures that prevent application onto crops during bloom at times of day when bees are foraging. Honey bees (Apis mellifera;Hymenoptera:Apidae) are at an increased risk of exposure to adjuvant tank mixtures while providing agricultural pollination services. Colony losses attributed to pesticide applications thought to have low risk to honey bees have been reported, highlighting the need to better understand the toxicity of adjuvants included in pesticide tank mixtures. This review summarizes current literature on the risks posed to honey bees by agricultural adjuvants and tank mix combinations of adjuvants with pesticides. Based on the current state of knowledge, we make recommendations to pesticide applicators, product manufacturers, regulatory agencies, and researchers regarding adjuvant toxicity to honey bees with the goal of reducing risks that adjuvants pose to honey bees and other beneficial insects.

Trace metals with heavy consequences on bees: A comprehensive review

The pervasiveness of human imprint on Earth is alarming and most animal species, including bees (Hymenoptera: Apoidea: Anthophila), must cope with several stressors. Recently, exposure to trace metals and metalloids (TMM) has drawn attention and has been suggested as a threat for bee populations. In this review, we aimed at bringing together all the studies (n = 59), both in laboratories and in natura, that assessed the effects of TMM on bees. After a brief comment on semantics, we listed the potential routes of exposure to soluble and insoluble (i.e. nanoparticle) TMM, and the threat posed by metallophyte plants. Then, we reviewed the studies that addressed whether bees could detect and avoid TMM in their environment, as well as the ways bee detoxify these xenobiotics. Afterwards, we listed the impacts TMM have on bees at the community, individual, physiological, histological and microbial levels. We discussed around the interspecific variations among bees, as well as around the simultaneous exposure to TMM. Finally, we highlighted that bees are likely exposed to TMM in combination or with other stressors, such as pesticides and parasites. Overall, we showed that most studies focussed on the domesticated western honey bee and mainly addressed lethal effects. Because TMM are widespread in the environment and have been shown to result in detrimental consequences, evaluating their lethal and sublethal effects on bees, including non-Apis species, warrants further investigations.

Genome-wide DNA methylation patterns in bumble bee (Bombus vosnesenskii) populations from spatial-environmental range extremes

Unraveling molecular mechanisms of adaptation to complex environments is crucial to understanding tolerance of abiotic pressures and responses to climatic change. Epigenetic variation is increasingly recognized as a mechanism that can facilitate rapid responses to changing environmental cues. To investigate variation in genetic and epigenetic diversity at spatial and thermal extremes, we use whole genome and methylome sequencing to generate a high-resolution map of DNA methylation in the bumble bee Bombus vosnesenskii. We sample two populations representing spatial and environmental range extremes (a warm southern low-elevation site and a cold northern high-elevation site) previously shown to exhibit differences in thermal tolerance and determine positions in the genome that are consistently and variably methylated across samples. Bisulfite sequencing reveals methylation characteristics similar to other arthropods, with low global CpG methylation but high methylation concentrated in gene bodies and in genome regions with low nucleotide diversity. Differentially methylated sites (n = 2066) were largely hypomethylated in the northern high-elevation population but not related to local sequence differentiation. The concentration of methylated and differentially methylated sites in exons and putative promoter regions suggests a possible role in gene regulation, and this high-resolution analysis of intraspecific epigenetic variation in wild Bombus suggests that the function of methylation in niche adaptation would be worth further investigation.

Heavy Metal Concentrations of Beeswax (Apis mellifera L.) at Different Ages

Beeswax is a naturally occurring product that worker bees produce. Beeswax is used in a variety of industries and pharmaceuticals. Humans utilize it extensively in cosmetics, medicinal formulations, and food manufacturing. Beeswax is an essential component of advanced contemporary beekeeping. Beekeepers, in particular, utilize significant amounts of beeswax to make beeswax comb foundation. In its natural condition, beeswax is white, but it becomes yellow then dark in color when it comes into touch with honey and pollen. The ongoing use of wax comb in bee activities (such as brood rearing, storage honey and bee bread), combined with environmental factors such as heavy metal and pesticide residues, resulted in a black color. Because of heavy metals can accumulate in wax for decades, beeswax can be a helpful tool for gathering data on hazardous contaminants in the environment. Because of their lipid-based chemical composition, beeswax combs act as a sink for numerous ambient pollutants as well as poisons when in the hive. The current study aims to measure nine heavy metals and important elements, including iron (Fe), chromium (Cr), zinc (Zn), copper (Cu), nickel (Ni), manganese (Mn), lead (Pb), cadmium (Cd), and cobalt (Co) in beeswax collected in the Behaira governorate region of Egypt between 2018 and 2022. Sample collection was conducted each year in triplicate. The samples were analyzed using an atomic absorption spectrophotometer. The quantity of metals in beeswax at different ages differed significantly. Depending on the wax age, Fe has the highest concentration in the range of 2.068 to 5.041 ppm, while Cd has the lowest ratio at 0.024 to 0.054 ppm from the first to fifth years old of comb age. The findings showed that as beeswax combs aged, the concentration of heavy metals rose. According to the study, it should gradually recycle beeswax combs each year and also adding new foundations.

Stress Response in the Honeybee (Apis mellifera L.) Gut Induced by Chlorinated Paraffins at Residue Levels Found in Bee Products

Chlorinated paraffins (CPs) have become global pollutants and are of considerable concern as a result of their persistence and long-distance transmission in the environment and toxicity to mammals. However, their risks to pollinating insects are unknown. Honeybees are classical pollinators and sensitive indicators of environmental pollution. Herein, the effects of CPs on the gut microenvironment and underlying mechanisms were evaluated and explored using Apis mellifera L. Both short- and medium-chain CPs had significant sublethal effects on honeybees at a residue dose of 10 mg/L detected in bee products but did not significantly alter the composition or diversity of the gut microbiota. However, this concentration did induce significant immune, detoxification, and antioxidation responses and metabolic imbalances in the midgut. The mechanisms of CP toxicity in bees are complicated by the complex composition of these chemicals, but this study indicated that CPs could substantially affect intestinal physiology and metabolic homeostasis. Therefore, CPs in the environment could have long-lasting impacts on bee health. Future studies are encouraged to identify novel bioindicators of CP exposure to detect early contamination and uncover the detailed mechanisms underlying the adverse effects of CPs on living organisms, especially pollinating insects.

Individual and social defenses in Apis mellifera: a playground to fight against synergistic stressor interactions

The honeybee is an important species for the agri-food and pharmaceutical industries through bee products and crop pollination services. However, honeybee health is a major concern, because beekeepers in many countries are experiencing significant colony losses. This phenomenon has been linked to the exposure of bees to multiple stresses in their environment. Indeed, several biotic and abiotic stressors interact with bees in a synergistic or antagonistic way. Synergistic stressors often act through a disruption of their defense systems (immune response or detoxification). Antagonistic interactions are most often caused by interactions between biotic stressors or disruptive activation of bee defenses. Honeybees have developed behavioral defense strategies and produce antimicrobial compounds to prevent exposure to various pathogens and chemicals. Expanding our knowledge about these processes could be used to develop strategies to shield bees from exposure. This review aims to describe current knowledge about the exposure of honeybees to multiple stresses and the defense mechanisms they have developed to protect themselves. The effect of multi-stress exposure is mainly due to a disruption of the immune response, detoxification, or an excessive defense response by the bee itself. In addition, bees have developed defenses against stressors, some behavioral, others involving the production of antimicrobials, or exploiting beneficial external factors.

Phytochemical, Morphological, and Physiological Variation in Different Ajowan (Trachyspermum ammi L.) Populations as Affected by Salt Stress, Genotype × Year Interaction and Pollination System

In the present research, 28 populations of ajowan (Trachyspermum ammi L.) were evaluated for agro-morphological traits and essential oil yield in two consecutive years. Then, selected ajowan populations from these two years were used for further morphophysiological and biochemical studies under different salinity levels (control, 60, 90, and 120 mM NaCl). The main components of the oil were thymol (32.7-54.29%), γ-terpinene (21.71-32.81%), and p-cymene (18.74-26.16%). Salt stress caused an increase in essential oil content in the Esfahfo and Qazvin populations. The highest total phenolic and flavonoid contents were found in the Arak population grown in 60 mM NaCl (183.83 mg TAE g^-1 DW) and the Yazd population grown in 90 mM NaCl (5.94 mg QE g^-1 DW). Moreover, the Yazd population exhibited the strongest antioxidant activity based on DPPH (IC₅₀ = 1566 µg/mL) under 60 mM NaCl and the highest reducing power (0.69 nm) under 120 mM NaCl. The results revealed that low and moderate salt stress improves the phytochemicals of ajowan seeds, which are useful for pharmaceutical and food applications. In this research, some morphological traits, as well as essential oil yield, were evaluated in open pollinated versus self-pollinated plants. As a result, plant height, number of flowering branches, and crown diameter significantly decreased in some populations, while a significant increase was obtained for number of flowers per umbel and seed numbers per umbel. Finally, self-pollination of ajowan might provide new insights for further breeding programs to increase oil or thymol content in ajowan.

Survey Results of Honey Bee Colony Losses in Winter in China (2009-2021)

There is growing concern that massive loss of honey bees can cause serious negative effects on biodiversity and ecosystems. Surveys of colony losses have been performed worldwide to monitor the dynamic changes and health status of honey bee colonies. Here, we present the results of surveys regarding winter colony losses from 21 provinces in China from 2009 to 2021, with a total of 1,744,324 colonies managed by 13,704 beekeepers. The total colony losses were low (9.84%; 95% Confidence Interval (CI): 9.60-10.08%) but varied among years, provinces, and scales of apiaries. As little is known about the overwintering mortality of Apis cerana, in this study, we surveyed and compared the loss rates between Apis mellifera and A. cerana in China. We found colonies of A. mellifera suffered significantly lower losses than A. cerana in China. Larger apiaries resulted in higher losses in A. mellifera, whereas the opposite was observed in A. cerana. Furthermore, we used generalized linear mixed-effects models (GLMMs) to evaluate the effects of potential risk factors on winter colony losses and found that the operation size, species, migration, migration×species interaction, and queen problems were significantly related to the loss rates. New queens can increase their colony overwintering survival. Migratory beekeepers and large operations reported lower loss rates.