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Viruses are one of the most potential risk factors that negatively affect the different life stages of honey bees. This study was conducted to determine the presence of infections caused by the deformed wing virus (DWV), black queen cell virus (BQCV), and acute bee paralysis virus (ABPV) in honey bees in the beekeeping regions of Burdur, along with obtaining information about their prevalence in this particular region. In our study, the adult bees were taken from 31 different beehives and comb samples that had different honey bee breeds and were sampled randomly from 15 beekeeping areas within the region. The collected samples were analyzed using the reverse transcriptase-polymerase chain reaction (RT-PCR), and the prevalence of DWV, BQCV, and ABPV infections were determined to be 74.19% (23/31), 25.81%, (8/31) and 74.19% (23/31), respectively. In this study, the distribution of positive samples and the rates of multiple infections were determined in the colonies. Of the positive honey bee samples, 12 (%38.71) were detected only for one virus, 9 (%29.03) were positive for two viruses (DWV-ABPV) and 8 (%25.81) were positive for all three viruses. In the present study, the presence of the three bee viruses that caused significant damage to the colonies by multiple infections in the Burdur region was determined with RT-PCR. To our knowledge, this is the first report of three mentioned bee infections in honey bees in the Burdur region. The revealed epidemiological conditions lead to the conclusion that serious measures are needed to control these infections in this region.

Introduction Honey bees (Apis mellifera) play key roles in food production performing complex behaviors, like self-grooming to remove parasites. However, the lipids of their central nervous system have not been examined, even though they likely play a crucial role in the performance of cognitive process to perform intricate behaviors. Lipidomics has greatly advanced our understanding of neuropathologies in mammals and could provide the same for honey bees. Objectives The objectives of this study were to characterize the brain lipidome of adult honey bees and to assess the effect of clothianidin (a neurotoxic insecticide) on the brain lipid composition, gene expression, and performance of self-grooming behavior under controlled conditions (cage experiments). Methods After seven days of exposure to oral sublethal doses of clothianidin, the bees were assessed for self-grooming behavior; their brains were dissected to analyze the lipidome using an untargeted lipidomics approach and to perform a high throughput RNAseq analysis. Results Compared to all other organisms, healthy bee brain lipidomes contain unusually high levels of alkyl-ether linked (plasmanyl) phospholipids (51.42%) and low levels of plasmalogens (plasmenyl phospholipids; 3.46%). This could make it more susceptible to the effects of toxins in the environment. A positive correlation between CL 18:3/18:1/14:0/22:6, TG 6:0/11:2/18:1, LPE 18:0e and intense self-grooming was found. Sublethal doses of a neonicotinoid altered PC 20:3e/15:0, PC 16:0/18:3, PA 18:0/24:1, and TG 18:1/18:1/18/1 levels, and affected gene expression linked to GPI-anchor biosynthesis pathway and energy metabolism that may be partially responsible for the altered lipid composition. Conclusion This study showed that lipidomics can reveal honey bee neuropathologies associated with reduced grooming behavior due to sublethal neonicotinoid exposure. The ease of use, unusual brain lipidome as well as characterized behaviors that are affected by the environment make honey bees a promising model organism for studying the neurolipidome and associations with neurobehavioral disorders.

Honey bees are important for ecological health, biodiversity preservation, and crop output. Antimicrobials, like Tetracyclines, are commonly used in agriculture, medicine, and beekeeping, bees might be exposed to Tetracycline residues in the environment either directly or indirectly. This study aimed to determine the effect of antibiotic treatment (Tetracycline) effect on the Bio-efficiency of the larvae honey bee (Apis mellifera jemenatica), when larvae honeybee workers were exposed to different concentrations of it, to see how long they survived after being exposed to it and affected this antibiotic to the histological structure of the midgut. The results demonstrated that the concentration (LC50=125.25 μg/ml) of antibiotics Tetracycline leads to kills half of the individuals. Our data indicate that the high concentrations of Tetracycline have a significant effect on the histological composition of the cells of the midgut of honeybee larvae. Antibiotic exposure can negatively impact the health of honey bees, especially Tetracycline because it is the most used antibiotic in apiculture.

Honey bees (Apis) are important pollinators for food crops and wild plants, but are facing great threats from pathogens and parasites, especially an obligate ectoparasitic mite, Varroa destructor. Cell invasion is a key step for V. destructor to reproduce, and the parasite displays remarkable host preference in this process. Varroa destructor made its host-shift from its original host, the Asian honey bee Apis cerana, to the new host, the European honey bee Apis mellifera several decades ago. However, it remains largely unstudied whether V. destructor shows a cell invasion preference between the two host species. Using cell invasion bioassays on a modified four-well arena, we showed that V. destructor significantly preferred to invade the worker and drone larvae of A. mellifera rather than A. cerana, suggesting that the new host is much more attractive to the parasite than the original one. Using gas chromatography-mass spectrometry (GC-MS), we revealed significant differences between the cuticular hydrocarbon (CHC) profiles of worker and drone larvae of the two bee hosts. The amounts of methyl-branched alkanes and alkenes (unsaturated CHCs), but not n-alkanes, were significantly different, and A. mellifera worker and drone larvae were found to express significantly higher amounts of methyl-alkanes, while A. cerana larvae produced higher amounts of alkenes. Cell invasion bioassays with glass dummies showed that the mites preferred the glass dummies coated with the CHCs of A. mellifera worker or drone larvae, which indicates a role of larval CHCs in mediating the preferential cell invasion of Varroa. The findings from this study extend our understanding of the host preference of V. destructor, and can potentially contribute to the development of effective strategies for mite control.

Management of Monilinia laxa, the causal agent of brown rot blossom blight in almond (Prunus dulcis), relies heavily on the use of chemical fungicides during bloom. However, chemical fungicides can have nontarget effects on beneficial arthropods, including pollinators, and select for resistance in the pathogen of concern. Almond yield is heavily reliant on successful pollination by healthy honey bees (Apis mellifera); thus, identifying sustainable, effective, and pollinator-friendly control methods for blossom blight during bloom is desirable. Flower-inhabiting microbes could provide a natural, sustainable form of biocontrol for M. laxa, while potentially minimizing costly nontarget effects on almond pollinators and the services they provide. As pollinators are sensitive to floral microbes and their associated taste and scent cues, assessing effects of prospective biocontrol species on pollinator attraction is also necessary. Here, our objective was to isolate and identify potential biocontrol microbes from an array of agricultural and natural flowering hosts and test their efficacy in suppressing M. laxa growth in culture. Out of an initial 287 bacterial and fungal isolates identified, 56 were screened using a dual culture plate assay. Most strains reduced M. laxa growth in vitro. Ten particularly effective candidate microbes were further screened for their effect on honey bee feeding. Of the 10, nine were found to both strongly suppress M. laxa growth in culture and not reduce honey bee feeding. These promising results suggest a number of strong candidates for augmentative microbial biocontrol of brown rot blossom blight in almond with potentially minimal effects on honey bee pollination.

In this preliminary study, we applied the Multivariate Curve Resolution- Alternating Least Squares (MCR-ALS) method to analyze the excitation-emission matrices of multifloral honey samples, combined with differential scanning calorimetry (DSC) to estimate infection of honey bee colonies with N. ceranae or V. destructor. Fluorescence spectroscopy combined with MCR-ALS was used to determine the ratio of the spectral components originating from proteins (C1) and phenolics (C2), two minor but essential constituents of honey, as a ratiometric indicator of infection level in related hives. The C1/C2 ratio decreased linearly with the increase of infection in both N. ceranae and V. destructor cases, the R2 was 0.941 and 0.912, respectively. Additionally, DSC has shown that the magnitude of changes in sugar environments of the honey samples, reflected in sugar phase transitions, rises with increasing infection level in bee colonies. These results indicate that fluorescence combined with MCR-ALS could be used for rapid, non-destructive and cheap screening of honey to estimate the level of infection of honey bee colonies.

Toxic element pollution is an ecological concern in the regions where mining, industry and agriculture are developing. Anthropogenic impact on the environment results in the reduction of the population of honey bees over the world with varying degrees of morbidity and mortality. Bees exposed to contaminants produce polluted products through various sources, including foraging activities on contaminated plants. Therefore, monitoring of honey bee products in terms of toxic elements is very important for food safety and for preventing potential future ecological problems. The data presented in this review are useful for bee health protection and improving the quality and safety of honey production chain.

The neuropeptide Pigment-Dispersing Factor (PDF) plays a prominent role in the circadian clock of many insects including honey bees. In the honey bee brain, PDF is expressed in about 15 clock neurons per hemisphere that lie between the central brain and the optic lobes. As in other insects, the bee PDF neurons form wide arborizations in the brain; but certain differences are evident. For example, they arborize only sparsely in the accessory medulla (AME), which serves as important communication center of the circadian clock in cockroaches and flies. Furthermore, all bee PDF neurons cluster together, which makes it impossible to distinguish individual projections. Here, we investigated the developing bee PDF network and found that the first three PDF neurons arise in the 3rd larval instar and form a dense network of varicose fibers at the base of the developing medulla that strongly resembles the AME of hemimetabolous insects. In addition, they send faint fibers toward the lateral superior protocerebrum. In last larval instar, PDF cells with larger somata appear and send fibers toward the distal medulla and the medial protocerebrum. In the dorsal part of the medulla serpentine layer, a small PDF knot evolves from which PDF fibers extend ventrally. This knot disappears during metamorphosis and the varicose arborizations in the putative AME become fainter. Instead a new strongly stained PDF fiber hub appears in front of the lobula. Simultaneously, the number of PDF neurons increases and the PDF neuronal network in the brain gets continuously more complex. This article is protected by copyright. All rights reserved.

The present research work was conducted to assess the impact of nutrient-enriched diet on the physiological activities and subsequently honey yield. Eighteen colonies of Apis mellifera L. were selected from Dera Ismail Khan region, KPK, Pakistan, during the winter and summer seasons, 2019–2020. Five pollen supplement diets were prepared and provided to screen out the palatable one to be fed as pollen alternative nutrition to bee bread. Results of diet consumption regarding mean data for consumption rate displayed that soybean flour enriched artificial diet was maximally consumed (74.34 g) by honey bees per week. Minimum consumption was observed for grinded groundnut enriched diet (64.62 g) which was relatively lesser than the other tested artificial diets. Results of area of worker brood disclosed that soybean flour fortified diet (1489.27 cm2/colony) statistically noteworthy than the other artificial diets whereas control (463.51 cm2/colony) was least effective. Highest bee strength (10.00 bee frames/colony) was noted in the bee colonies fed with soybean flour fortified diet, date paste (8.0 bee frames/colony) was the next effective one, among the tested pollen replacement diets whereas relatively least (5 bee frames/colony) was noticed in case of grinded groundnut. Highest body weight (12.41 g) of neonate bees was noted in case of soybean enriched diet while lowermost (5.31 g) was noted in control bees. Results of wax cell built up and foraging efficiency were also superior in artificial diets than respective control bees. Hence, artificial diets especially soybean-enriched pollen alternative diet can boost up the physiology of honey bee leading to increased honey yield and profit.

A decline in pollinating insect populations has been detected in recent years. Its causal factors include pathogens, among which RNA viruses have been the most notable. Numerous insect species could act as reservoirs for these viruses, resulting in emerging infectious diseases for new hosts. To date, ten honey bee viruses have been identified in Argentina, some of which have been found in other pollinators and non-pollinators that share the environment. The objective of this study was to review the available scientific literature related to the presence and dispersion of RNA viruses in the Apoidea species in Argentina. After a first search, 178 citations were found using keywords such as ‘RNA virus’, ‘insects’, and ‘Argentina’, and redefining other keywords such as ‘bees’, ‘pollinators’ and ‘non-pollinators’, 30 citations were found. While this could lead to a decrease in the populations of the new hosts, the spread of RNA viruses could lead to emerging infectious diseases in them.

BACKGROUND Almond production in California is an intensively managed agroecosystem dependent on managed pollination by honey bees, Apis mellifera L. A recent laboratory study reported synergism in honey bees between chlorantraniliprole, a common diamide insecticide used in almond orchards, and the fungicide propiconazole. Indeed, there is an emerging body of evidence that honey bee cytochrome P450 monooxygenases of the CYP9Q subfamily are involved in the detoxification of insecticides across a diverse range of chemical classes. The objective of the present study was to unveil the molecular background of the described synergism and to explore the potential role of CYP9Q enzymes in diamide detoxification. RESULTS Our study confirmed the previously reported synergistic potential of propiconazole on chlorantraniliprole in acute contact toxicity bioassays, whereas no synergism was observed for flubendiamide. Fluorescence-based biochemical assays revealed an interaction of chlorantraniliprole, but not flubendiamide, with functionally expressed CYP9Q2 and CYP9Q3. These findings were validated by an increased chlorantraniliprole tolerance of transgenic Drosophila lines expressing CYP9Q2/3, and an analytically confirmed oxidative metabolism of chlorantraniliprole by recombinantly expressed enzymes. Furthermore, we showed that several triazole fungicides used in almond orchards, including propiconazole, were strong nanomolar inhibitors of functionally expressed honey bee CYP9Q2 and CYP9Q3, whereas other fungicides such as iprodione and cyprodinil did not inhibit these enzymes. CONCLUSION Honey bee CYP9Q enzymes are involved in chlorantraniliprole metabolism and inhibited by triazole fungicides possibly leading to synergism in acute contact toxicity bioassays. Our mechanistic approach has the potential to inform tier I honey bee pesticide risk assessment.

Vibro-acoustic communication is used by honey bees in many different social contexts. Our previous research showed that workers interact with their queen outside of the swarming period by means of wing-beating behaviour. Therefore, the aim of this study was to verify the hypothesis that the wing-beating behaviour of workers attending the queen stimulates her to lay eggs. The behaviour of workers and the queen was recorded using a high-speed camera, at first in the presence of uncapped brood in the nest and then without one. None of the queens performed wing-beating behaviour. On the other hand, the workers attending the queen demonstrated this behaviour two times per minute, on average, even in the presence of uncapped brood in the nest. After removing the combs with the uncapped brood, the incidence of wing-beating behaviour increased significantly to an average of four times per minute. Wing-beating behaviour did not differ significantly in its characteristics when uncapped brood was present or absent in the nest. During 3 days after removing the combs with the uncapped brood, there was no significant increase in the rate of egg lying by the queen. Therefore, the results presented here do not convincingly confirm that the wing-beating behaviour of workers affects the rate of queen's egg-lying. This negative result can be related to colony disturbance and longer time required by the queen to increase egg production.

Brain transcriptional regulatory network for behavior demonstrates that brain gene expression in the honey bee can be accurately predicted from the expression transcription factors (TFs), but roles for specific TFs are less understood. Mushroom bodies (MBs) are important for learning, memory and sensory integration in the honey bee brain. A transcription factor, Mblk-1, expressed preferentially in the large-type Kenyon cells of the honeybee MBs is predicted to be involved in brain function by regulating transcription of its target genes in honey bee. However its function and the mechanism of regulation in behavior of honey bee is still obscure. Here we show that Mblk-1 had significantly higher expression in the brains of forager bees relative to nurse bees. Mblk-1 was significantly inhibited in bees fed siRNA. In addition, inhibition of Mblk-1 decreased sucrose responsiveness in foragers. Finally, we determined that Mblk-1 regulated the mRNA of AmGR1. These findings suggest that Mblk-1 may target AmGR1 to regulate the sucrose responsiveness of foragers. This article is protected by copyright. All rights reserved.

Recapping of Varroa destructor-infested brood cells is a trait that has recently attracted interest in honey bee breeding to select mite-resistant Apis mellifera colonies. To investigate the genetic architecture of this trait, we evaluated a sample of A. mellifera mellifera colonies (N = 155) from Switzerland and France and performed a genome-wide association study, using a pool of 500 workers per colony for next-generation sequencing. The results revealed that two QTL were significantly (P < 0.05) associated with recapping of V. destructor-infested brood cells. The best-associated QTL is located on chromosome 5 in a region previously found to be associated with grooming behaviour, a resistance trait against V. destructor, in A. mellifera and Apis cerana. The second best-associated QTL is located on chromosome 4 in an intron of the Dscam gene, which is involved in neuronal wiring. Previous research demonstrated that genes involved in neuronal wiring are associated with recapping and varroa sensitive hygiene. Therefore, our study confirms the role of a gene region on chromosome 5 in social immunity and simultaneously provides novel insights into genetic interactions between common mite resistance traits in honey bees.

Honey bee colony health has received considerable attention in recent years, with many studies highlighting multifactorial issues contributing to colony losses. Disease and weather are consistently highlighted as primary drivers of colony loss, yet little is understood about how they interact. Here, we combined disease records from government honey bee health inspections with meteorological data from the CEDA to identify how weather impacts EFB, AFB, CBP, varroosis, chalkbrood and sacbrood. Using R-INLA, we determined how different meteorological variables influenced disease prevalence and disease risk. Temperature caused an increase in the risk of both varroosis and sacbrood, but overall, the weather had a varying effect on the six honey bee diseases. The risk of disease was also spatially varied and was impacted by the meteorological variables. These results are an important step in identifying the impacts of climate change on honey bees and honey bee diseases.

The honey bee Apis mellifera is a model organism for sociogenomics and one of the most important managed pollinators. High mortalities experienced by honey bee colonies over the past several decades are expected to have a substantive effect on crop pollination and global food security. These threats and the availability of a growing number of genomic resources for the honey bee have motivated research on how genetics and genomics can be practically applied to manage bee health. The authors review 3 such applications: (1) Certification of bee lineages using single-polymorphism markers; (2) breeding bees using marker-assisted selection; (3) diagnosing honey bee stressors using biomarkers.

Honey bee colonies can be afflicted by serious conditions beyond infectious etiologies. Noninfectious conditions, such as starvation, laying worker colonies, and environmental dysregulation, can be as devastating as any disease. Improper hive monitoring and care often are the underlying causes of noninfectious conditions and each condition may be prevented by instituting best management practices.

Annual losses of honey bee colonies are high in the United States, with losses often attributed to the effects of the ectoparasitic mite, Varroa destructor, and its associated viruses (e.g., Deform...

Pollinators are in decline thanks to the combined stresses of disease, pesticides, habitat loss, and climate. Honey bees face numerous pests and pathogens but arguably none are as devastating as Deformed wing virus (DWV). Understanding host-pathogen interactions and virulence of DWV in honey bees is slowed by the lack of cost-effective high-throughput screening methods for viral infection. Currently, analysis of virus infection in bees and their colonies is tedious, requiring a well-equipped molecular biology laboratory and the use of hazardous chemicals. Here we describe virus clones tagged with green fluorescent protein (GFP) or nanoluciferase (nLuc) that provide high-throughput detection and quantification of virus infections. GFP fluorescence is measured noninvasively in living bees via commonly available long-wave UV light sources and a smartphone camera, or a standard ultraviolet transilluminator gel imaging system. Nonlethal monitoring with GFP allows continuous screening of virus growth and serves as a direct breeding tool for identifying honey bee parents with increased antiviral resistance. Expression using the nLuc reporter strongly correlates with virus infection levels and is especially sensitive. Using multiple reporters, it is also possible to visualize competition, differential virulence, and host tissue targeting by co-occuring pathogens. Finally, it is possible to directly assess the risk of cross-species "spillover" from honey bees to other pollinators and vice versa.

Suppressed mite reproduction (SMR) is an important trait for the selection of Varroa resistant honey bee colonies. It has repeatedly been assumed that SMR is an effect of varroa sensitive hygiene (VSH) when hygienic bees preferably remove those brood cells where the mite has reproduced. We here compare the VSH behaviour of honey bees toward brood cells artificial infested with a varroa mite. By infesting half of the brood cells directly after the cell capping and the other half only 24 h later, we established two groups with high (> 75%) and low (

Understanding habitat needs and patch utilization of wild and managed bees has been identified as a national research priority in the United States. We used occupancy models to investigate patterns of bee use across 1030 transects spanning a gradient of floral resource abundance and richness and distance from apiaries in the Prairie Pothole Region (PPR) of the United States. Estimates of transect use by honey bees were nearly 1.0 during our 3.5‐month sampling period, suggesting honey bees were nearly ubiquitous across transects. Wild bees more frequently used transects with higher flower richness and more abundant flowers; however, the effect size of the native flower abundance covariate (β^native = 3.90 ± 0.65 [1SE]) was four times greater than the non‐native flower covariate (β^non‐native = 0.99 ± 0.17). We found some evidence that wild bee use was lower at transects near commercial apiaries, but the effect size was imprecise (β^distance = 1.4 ± 0.81). Honey bees were more frequently detected during sampling events with more non‐native flowers and higher species richness but showed an uncertain relationship with native flower abundance. Of the 4039 honey bee and flower interactions, 85% occurred on non‐native flowers, while only 43% of the 738 wild bee observations occurred on non‐native flowers. Our study suggests wild bees and honey bees routinely use the same resource patches in the PPR but often visit different flowering plants. The greatest potential for resource overlap between honey bees and wild bees appears to be for non‐native flowers in the PPR. Our results are valuable to natural resource managers tasked with supporting habitat for managed and wild pollinators in agroecosystems., We investigated use of grassland patches by wild bees and honey bees. Our study showed that while honey bees and wild bees commonly co‐occurred at the same resource patches, they often visited different species of flowers within patches.

Many food crops rely on pollination by animals. Historically, wind and wild organisms provided pollination as an ecosystem service that varied across agroecological zones, cropping systems, and time. The value of these pollination services is likely substantial but has not been estimated reliably. More recently, pollination services in major crop-producing regions have been provided through organized markets, primarily the rental of honey bees. The sustainability of commercially provided pollination services is being challenged by parasites, diseases, pesticide exposures, poor nutrition, and Colony Collapse Disorder. Economic analyses indicate that honey bee rental markets have been able to adjust to those challenges, at least to date. Understanding the future sustainability of rental markets requires greater knowledge of the contributions of wild pollinators, optimal management of pollination services from wild and managed organisms, and the value of pollination services provided by wild and managed organisms.

The study aimed to investigate the relationship between colony survival and some preventive procedures. The experiments were conducted in Sulemani governorate during August, September and October 2020. Seventy-two colonies were tested in four localities ( Qaradax , Sulaimani center, Mergapan, and Sartake bamo ); (18 colonies for each location). The tested colonies were treated with; probiotics, formic acid, eucalyptus, Tetracycline and Terramycin. Larger brood area was found in all treated colonies compared to untreated ones. Colonies provided with probiotics showed significantly more brood than untreated colonies in the four locations. Maximum brood area was 203.667 (inch)2 in Sartake bamo followed by 199.667 (inch)2 in Mergapan; then 179.000 (inch)2 in Sulaimani center. While the brood area was not more than 15.667 (inch)2 in all untreated colonies in the four tested apiaries. Colonies provided with probiotics showed significantly more density of adult workers than untreated colonies in the four locations. Maximum area covered with adult workers (density) was 6.667 Lf. (Langstroth frame)in Sartake bamo followed by 6.333 Lf. inMergapan; then 6.000 Lf. in those treated with Formic acid in Sartake bamo. While the density of adult workers was not more than 1.000 Lf. in all untreated colonies in the four tested apiaries. Using probiotics and organic acid treatments were the best preventive measures.

Research Highlight: Norton, A. M., Remnant, E. J., Tom, J., Buchmann, G., Blacquiere, T., & Beekman, M. (2021). Adaptation to vector-based transmission in a honeybee virus. Journal of Animal Ecology, 90, https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.13493. In their paper on the adaptation to vector-based transmission via the mite Varroa destructor in a honeybee virus, Norton et al. study how high versus low levels of a viral vector affect viral load and potential competition between two strains of Deformed Wing Virus, an important highly virulent bee virus with the potential to spill-over into other pollinators and bee-associated insect species. This paper addresses two very timely issues, on the one hand on viral evolutionary ecology in response to vector-borne transmission, and on the other hand providing much needed information on an important honey bee pathogen. Using a complex natural system, this study shows that vector-borne transmission, and the control of the vector, can select for complex host-pathogen-vector interactions and that adaptations to changing transmission landscapes in fast evolving pathogens can create conditions for emerging pathogens to transition to endemic diseases.

Propolis is a honey bee product containing chiefly beeswax and resins originated from plant buds or exudates. Propolis resin exerts a diversity of biological activities, such as antitumoral, anti-inflammatory, antimicrobial, and defense of the hive against pathogens. Chemical standardization and identification of botanical sources is crucial for characterization of propolis. Types of Brazilian propolis are characteristic of geographical regions and respective biomes, such as savannas (Cerrado), mangroves, dry forest (Caatinga), rain forests (Amazon, Atlantic, and Interior forests), altitudinal fields ("Campos Rupestres"), Pantanal, and Araucaria forests. Despite the wide diversity of Brazilian biomes and flora, relatively few types of Brazilian propolis and corresponding resin plant sources have been reported. Factors accounting for the restricted number of known types of Brazilian propolis and plant sources are tentatively pointed out. Among them, the paper discusses constraints that honey bees must overcome to collect plant exudates, including the characteristics of the lapping-chewing mouthpart of honey bee, which limit their possibilities to cut and chew plant tissues, as well as chemical requirements that plant resins must fulfil, involving antimicrobial activity of its constituents and innocuity to the insects. Although much still needs to be done toward a more comprehensive picture of Brazilian propolis types and corresponding plant origins, the prospects indicate that the actual diversity of plant sources of honey bee propolis will remain relatively low.

Insect pollination is crucial for the maintenance of natural and managed ecosystems but the functioning of this ecosystem service is threatened by a worldwide decline of pollinators. Key factors in this situation include the spread and interspecific transmission of pathogens worldwide through the movement of managed pollinators. Research on this field has been mainly conducted in some particular species, while studies assessing the interspecific transmission of pathogens at a community level are scarce. However, this information is pivotal to design strategies to protect pollinators. Herein, we analysed the prevalence of two common microsporidia pathogens of managed honey bees (Nosema ceranae and N. apis) in bee communities of semiarid Mediterranean areas from the Southeast of the Iberian Peninsula. Our results confirm the ability of N. ceranae to disperse across wild bee communities in semiarid Mediterranean ecosystems since it was detected in 36 Apoidea species (39% of the sampling; for the first time in nine genera). The prevalence of the pathogen did not show any phylogenetic signal which suggests a superfamily host range of the pathogen or that wild bees may be acting only as vectors of N. ceranae. In addition, N. apis was detected in an Eucera species, which is the second time it has been detected by molecular techniques in a host other than the honey bee. Our study represents the primary assessment of the prevalence of microsporidia at community level in Mediterranean areas and provides outstanding results on the ability of Nosema pathogens to spread across the landscape.

Background There is one queen in each honey bee, Apis mellifera L., colony under normal conditions. This queen performs egg laying and pheromonal control in the colony. All genetic characteristics of bee workers and drones depend on the queen. This reflects the importance of bee queen in the colony. In this review, behaviors of honey bee queens are presented and further studies are suggested to fill in gaps in knowledge. Main body The major studies about behaviors of honey bee queens either inside or outside the colony were reviewed. Some behavioral aspects especially egg laying pattern, sperm storage and utilization, conflict between queens, and the role of the queens in swarming and absconding have gained relatively few attention. Also, some other points such as the ability of a queen to transmit parasites after mating to her offspring and effects of pesticides on queen rearing and characteristics of emerged queens were highlighted. Conclusion This study highlighted the points that require further detailed studies. This review article may stimulate others toward performing specific future studies on bee queens.

To investigate the value of atypical foraging behavior of honey bees (Apis mellifera) during dearth, we compared the number of days survived in vitro among young adult honey bees kept in hoarding c...

This review will summarise existing tools and resources and highlight areas of focus for the insects as food and feed industry for the production of insects as alternative protein sources. By applying knowledge gained from other agricultural organisms coupled with the ease of insect population growth and rearing capabilities, and the increase in biotechnological advances, strains optimised for various economic and biological traits should be one of the most attainable goals for researchers and insect farmers alike. We have reviewed strengths (and weaknesses) of various genetic and genomic approaches, and consider the future of insect farming in the context of genetic and genomic selection of insects.

Host-parasite co-evolution is a process of reciprocal, adaptive genetic change. In natural conditions, parasites can shift to other host species, given both host and parasite genotypes allow this. Even though host-parasite co-evolution has been extensively studied both theoretically and empirically, few studies have focused on parasite gene flow between native and novel hosts. Nosema ceranae is a native parasite of the Asian honey bee Apis cerana, which infects epithelial cells of mid-guts. This parasite successfully switched to the European honey bee Apis mellifera, where high virulence has been reported. In this study, we used the parasite N. ceranae and both honey bee species as model organisms to study the impacts of two-host habitat sharing on parasite diversity and virulence. SNVs (Single Nucleotide Variants) were identified from parasites isolated from native and novel hosts from sympatric populations, as well as novel hosts from a parapatric population. Parasites isolated from native hosts showed the highest levels of polymorphism. By comparing the parasites isolated from novel hosts between sympatric and parapatric populations, habitat sharing with the native host significantly enhanced parasite diversity, suggesting there is continuing gene flow of parasites between the two host species in sympatric populations.

Background MicroRNA (miRNA) is a class of small noncoding RNAs, which targets on thousands of mRNA and thus plays important roles in many biological processes. It has been reported that miRNA has cross-species regulation functions between parasitoid-host, or plant-animal, etc. For example, several plant miRNAs enter into the honey bees and regulate gene expression. However, whether cross-species regulation function of miRNAs is a universal mechanism remains a debate question. Results We have evaluated transmission of miRNAs from sunflower and sedr plants into the midgut of honey bee using RNA-Seq analyses complemented with confirmation by RT-qPCR. The results showed that at least 11 plant miRNAs were found in the midgut of honey bee feeding by sunflower and sedr pollen. Among which, nine miRNAs, including miR-30d, miR-143, miR-148a, miR-21, let-7 g, miR-26a, miR-126, miR-27a, and miR-203, were shared between the sunflower- and sedr-fed honey bees, suggesting they might have essential roles in plant-insect interactions. Moreover, existence of these co-shared miRNAs presents a strong evidence to support the successful transmission of miRNAs into the midgut of the insect. In total, 121 honeybee mRNAs were predicted to be the target of these 11 plant-derived miRNAs. Interestingly, a sedr-derived miRNA, miR-206, targets on 53 honeybee genes. Kyoto Encyclopedia of Genes and Genome (KEGG) analyses showed that these target genes are significantly involved in hippo signaling pathway-fly, Wnt signaling pathway, and N-Glycan biosynthesis. Conclusions In summary, these results provide evidence of cross-species regulation function of miRNA between honeybee and flowering host plants, extending our understanding of the molecular interactions between plants and animals.

The concerns over honey bee health and colony collapse have led to an increased interest in the potential for beneficial bacteria as an intervention. However, the efficacy of this approach is mostly unknown because the application of bacterial adjuncts to hives has not often proceeded by understanding the strains being applied or how they function. This article summarizes the effects reported from published studies (2004–2020) that have experimentally tested the influence of beneficial bacteria, including probiotics, on honey bee immune function, pathogen resistance, or colony productivity. The meta-analysis shows that bacterial intervention can improve bee survival against American foulbrood and Nosema infection, and increase honey yields, but the underlying molecular correlates remain poorly understood. There is some evidence that honey bee–derived bacteria could be superior to exogenous bacterial species, although further evaluation is needed. We advocate for a more organized and transparent approach that includes the rationale for strain choice and delivery, a thorough description of treatment formulations, viable counts and their application to hives, and improved design of experimental field trials to consistently include controls and other features that allow interpretation of results. Successful studies should also be validated for efficacy and reproducibility.

Honey bee colony losses worldwide call for a more in-depth understanding of the pathogenic and mutualistic components of the honey bee microbiota and their relation with the environment. In this descriptive study, we characterized the yeast and bacterial communities that arise from six substrates associated with honey bees: corbicular pollen, beebread, hive debris, intestinal contents, body surface of nurses and forager bees, comparing two different landscapes, Minas Gerais, Brazil and Maryland, United States. The sampling of five hives in Brazil and four in the USA yielded 217 yeast and 284 bacterial isolates. Whereas the yeast community, accounted for 47 species from 29 genera, was dominated in Brazil by Aureobasidium sp. and Candida orthopsilosis, the major yeast recovered from the USA was Debaryomyces hansenii. The bacterial community was more diverse, encompassing 65 species distributed across 31 genera. Overall, most isolates belonged to Firmicutes, genus Bacillus. Among LAB, species from Lactobacillus were the most prevalent. Cluster analysis evidenced high structuration of the microbial communities, with two distinguished microbial groups between Brazil and the United States. In general, the higher difference among sites and substrates were dependents on the turnover effect (~ 93% of the beta diversity), with a more pronounced effect of nestedness (~ 28%) observed from Brazil microbiota change. The relative abundance of yeasts and bacteria also showed the dissimilarity of the microbial communities between both environments. These results provide a comprehensive view of microorganisms associated with A. mellifera, highlighting the importance of the environment in the establishment of the microbiota associated with honey bees. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-021-00539-7.

American foulbrood is a devastating disease of honey bee, causing economic loss in the beekeeping industry. The disease mainly causes reduction in honey bee populations which negatively affect the honey bee’s major role as natural pollinators of significant crops and wildflowers. Thus, it is crucial to develop safe efficient strategies to control the disease and to improve bee colony health. Using lactic acid bacteria (LAB) as an alternative to chemical treatments is a promising novel technique for tackling honey bee diseases and improving their immunity. The endogenous LAB isolates were recovered from honey bee gut samples collected from different apiaries in two Egyptian governorates and screened for antagonistic activities against Paenibacillus larvae (pathogen of AFB disease). The results showed that 53.3% of tested LAB isolates (n = 120) exhibited antagonistic activities against P. larvae. The minimum inhibitory concentration and minimum bactericidal concentration of the most potent LAB isolate (with an inhibition zone of 44 mm) were 100 and 125 µL/mL, respectively. 16S rRNA sequencing identified the most potent isolate as Fructobacillus fructosus HI-1. The bioactive metabolites of F. fructosus were extracted with ethyl acetate and fractionated on thin-layer chromatography (TLC); also, bioactive fractions were detected. Heptyl 2-methylbutyrate, di-isobutyl phthalate, d-turanose, heptakis (trimethylsilyl), di-isooctyl phthalate, and hyodeoxycholic acid compounds were identified in the bioactive fractions. The result explores the promising administration of probiotic metabolites to control honey bee AFB disease, as a natural tool to substitute antibiotics and chemicals in disease-controlling strategies.

Pollen had a wide range of effects on honey bee. Caged honey bee workers were used to determine the nutritional effects of four main types of pollen collected by honey bee colonies from the study area on the food consumption rates, bees age, the development of the hypopharyngeal (HPG) acini and acid gland (AG) sacs in honey bee workers. Additionally, chemical analysis of the selected pollen types was performed. Pollen diets were as follows: broad bean pollen, date palm pollen, clover pollen, maize pollen and mixture of the for mentioned typrs beside the control pollen diet. The highest mean consumption was observed between 4th and 6th of day aged bees in all diets (23.05 mg./bee/3days). The highest quantity of food consumption was recorded in the 18th day when the workers were fed on date palm pollen (75.42 mg), while the lowest recorded 59.17 mg from maize pollen treatment. The highest mean acinal surface area of HPG was 0.0451mm2, which measured at 9 days-old of bees in all diets. While the workers fed on mixture pollen diet had the highest significant mean recorded the acinal surface area of HPG 0.0450mm2 comparing of 0.0223mm2 in control. The considering increment in average volume of acid gland sac with had been obtained at 18 days-old (0.7276mm3) that resembles the highest significant degree, the greatest mean volume of AG sacs was observed when bees were fed on broad bean pollen (0.6419mm3), while the lowest mean was 0.3643mm3 in control.

The Asian honey bee species i.e., Apis cerana (the eastern honey bee), A. dorsata (the giant honey bee), and the western or European honey bee (A. mellifera) collected from Pakistan were studied using partial sequences from two mitochondrial genes (i) the Cytochrome c oxidase I (COI) and (ii) the mitochondrially encoded NADH dehydrogenase 5 (ND5) and then compared with other honey bees sequences (already submitted from different countries around the globe) obtained after the national center for biotechnology information (NCBI). DNA sequences were analyzed employing molecular evolutionary genetics analysis and Kimura 2-parameter model, neighbor-joining method was applied to investigate phylogenetic relationships, and DNA sequence polymorphism was applied to measure the genetic diversity within the genus Apis. The phylogenetic analyses yielded consistent results. Based on COI gene fragment in two Asian and European honey bee species from Pakistan and from other countries showed considerable genetic diversity levels and deviation among the species. While in contrast the phylogenetic analyses based on ND5 gene fragment in Asian and European honey bee species from Pakistan and other countries showed comparatively higher genetic diversity indices and variations than the COI gene. So, in the genus Apis, the mitochondrial ND5 region has shown the possibility to answer the interactions among species. A further detailed work (by linking the analysis of other genomic and mitochondrial genes) is required for good quality solution to establish the concise genetic diversity and interaction among the Apis species. The objective of this study was to explore the extent of genetic differences and phylogenetic links among the three kinds of honey bee species from Pakistan and comparing them with other bee species around the globe.

Microbes, including bacteria and viruses, are the main threats to the health of honey bee colonies, and cause great losses to beekeepers. Rapid and accurate diagnosis is the key to controlling and eliminating honey bee diseases, and preventing them from spreading and causing an outbreak. This review summarizes recent advances in techniques to detect honey bee diseases, including traditional methods such as polymerase chain reaction, and next-generation sequencing methods, and how they are applied in the diagnosis and management of such diseases. It also discusses how these methods have revolutionized disease detection, and presents the future directions in the field of clinical diagnostics.

Learning and memory are important biological processes that allow for optimized honey bee behavior. Factors negatively affecting bee cognition are important contributors to declines in pollination and food security. Agrochemical use, including herbicides, is one of the primary stressors linked to bee decline. Predicted agricultural expansion and associated increased use of glyphosate combined with scarcity of honey bees further highlights the need to understand the relationship between glyphosate and honey bee cognition and health. Here we investigated the effect of field-realistic doses of glyphosate on honey bee olfactory learning and memory. We used the conditioning of the Proboscis Extension Reflex (PER) to evaluate olfactory absolute conditioning. We found no differences in olfactory PER performance between glyphosate-exposed and control bees. We also did not find differences in olfactory memory retrieval at 15 min or 24 h after conditioning between exposed and non-exposed bees. However, we found that sublethal doses of glyphosate impaired memory retention; bees exposed to sublethal doses of glyphosate showed a decay trajectory of learned information, while in non-exposed bees the trajectory had a positive increment with time. This trend in memory retention was significantly different between bees exposed to 1500 ng and controls. Implications for insect conservation: Field-realistic doses of glyphosate had negative effect on memory dynamics in the honey bee. These results suggest glyphosate affects time-dependent neural mechanisms underlying information processing. This negative effect contributes to declines in pollination function and food security. We highlight the need to critically evaluate the cost-benefit analysis of indiscriminate glyphosate use.

In June of 2013 an application of dinotefuran on an ornamental planting of European linden trees (Tilia cordata Mill. [Malvales: Malvalceae]) in a shopping mall parking lot in Wilsonville, Oregon provoked the largest documented pesticide kill of bumble bees in North America. Based on geographic information systems and population genetic analysis, we estimate that between 45,830 and 107,470 bumble bees originating from between 289 and 596 colonies were killed during this event. Dinotefuran is a neonicotinoid that is highly effective in exterminating and/or harming target pest insects and non-target beneficial insects. Analysis to detect the concentration of pesticides in flowers that received foliar application revealed that the minimum reported dinotefuran concentration of a sampled T. cordata flower was 7.4 ppm, or in excess of 737% above the LC50 of the beneficial pollinator, the honey bee (Apis mellifera Linnaeus, 1758 [Hymenoptera: Apidae]). Furthermore, sampled Vosnesensky bumble bees (Bombus vosnesenskii Radoskowski, 1862 [Hymenoptera: Apidae]) were found to have an average dinotefuran concentration of 0.92 ppm at the time of death, which exceeds the maximum LC50 of A. mellifera (0.884 ppm). Our study underscores the lethal impact of the neonicotinoid pesticide dinotefuran on pollinating insect populations in a suburban environment. To our knowledge, the documentation and impact of pesticide kills on wild populations of beneficial insects has not been widely reported in the scientific literature. It is likely that the vast majority of mass pesticide kills of beneficial insects across other environments go unnoticed and unreported.

Natural honey has various ingredients in it that contribute to its incredible properties. The aim of this investigation was to evaluate the physicochemical and antibacterial activity of various Apis honey from Coorg, Karnataka. Four samples of Apis honey viz., A. florea, A. mellifera, A. cerana and A. dorsata were collected from various regions of Coorg, Karnataka. The honey samples' physicochemical properties and antibacterial activities against Streptococcus sp., Staphylococcus aureus, Bacillus subtilis and Enterococcus sp were determined in vitro. The moisture and ash content varied from 13.6 - 17.2% and 0.32 – 0.49%, respectively. Hydroxy methyl furfurals) content of A. dorsata honey samples was highest with 9.2±0.5 mg/Kg and least was recorded with 6.8±0.4 mg/Kg for A. florae honey. The reducing sugar content of A. florea honey sample was highest with 87.5±3.2 (%) and the peroxide levels were in the range of 10.2 – 14.9 µg/g/h at 20°C. The antibacterial assay revealed that S. aureus, Enterococcus sp and Streptococcus sp were most susceptible against the honey varieties tested and minimum inhibitory concentration (MIC) values between 25-6.5 (%v/v) were determined. In conclusion, honey varieties from Coorg could be used in specific antibacterial prophylaxis as the activity depends on the honey bee species, their metabolism and floral sources in specific geographical regions.

The alimentary canal carries out many functions critical to insect physiology, including digesting and absorbing nutrients and water, housing beneficial gut bacteria, and eliciting immunological responses. The midgut, in particular, is a compartment for digestion and absorption and serves as a first point of contact between ingested pathogens and the insect immune system. Recently, we found the protein vitellogenin (Vg) localized in midgut cells of some honey bee workers. Vg is an important egg-yolk precursor protein in nearly all oviparous animals, but it also has immunological functions shared across many taxa. Additional and unexpected Vg functions have been characterized in honey bees, but none of these functions involve the midgut directly. Therefore, we sought to map out how Vg is localized and expressed in this organ across the two most common worker bee behavioral groups, namely nurses and foragers. We used immunohistochemistry and quantitative reverse transcription PCR to show Vg has different localization patterns in nurses and foragers and limited gene expression. Our study provides a platform for building a more detailed understanding of the possible roles of Vg in insect midgut cells, and it adds to the current knowledge of this fascinating, multi-functional protein.

Honey bees pollinate various crops and wild plants which ensures food security. However, in this modern world, bees are suffering. Decreasing global domesticated and wild bee populations while the demand for agricultural pollination services is increasing is a matter of concern. Colony losses are driven by such factors or interactions as changing environmental conditions, exposure to agrochemicals, parasite and pathogens attack and decreased flower abundance and diversity. All these stresses individually or together affect the immune system of bees and consequently bee fitness. Poor nutrition is the key stressor as it directly suppresses the immune system and reduces host resistance to other stressors. To cope with these stresses, honey bees have well-developed individual and social immune systems which initiate several defence reactions, but its activation, maintenance and use are detrimental for bee survival as it occurs at the cost of bee health. This review summarizes the causal factors and their possible interaction responsible for immune suppression in honey bees.