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Encerrado-Manriquez AM, Pouv AK, Fine JD, Nicklisch SCT. Enhancing knowledge of chemical exposures and fate in honey bee hives: Insights from colony structure and interactions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170193. [PMID: 38278225 DOI: 10.1016/j.scitotenv.2024.170193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/13/2024] [Accepted: 01/13/2024] [Indexed: 01/28/2024]
Abstract
Honey bees are unintentionally exposed to a wide range of chemicals through various routes in their natural environment, yet research on the cumulative effects of multi-chemical and sublethal exposures on important caste members, including the queen bee and brood, is still in its infancy. The hive's social structure and food-sharing (trophallaxis) practices are important aspects to consider when identifying primary and secondary exposure pathways for residential hive members and possible chemical reservoirs within the colony. Secondary exposures may also occur through chemical transfer (maternal offloading) to the brood and by contact through possible chemical diffusion from wax cells to all hive members. The lack of research on peer-to-peer exposures to contaminants and their metabolites may be in part due to the limitations in sensitive analytical techniques for monitoring chemical fate and dispersion. Combined application of automated honey bee monitoring and modern chemical trace analysis techniques could offer rapid progress in quantifying chemical transfer and accumulation within the hive environment and developing effective mitigation strategies for toxic chemical co-exposures. To enhance the understanding of chemical fate and toxicity within the entire colony, it is crucial to consider both the intricate interactions among hive members and the potential synergistic effects arising from combinations of chemical and their metabolites.
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Affiliation(s)
| | - Amara K Pouv
- Department of Environmental Toxicology, University of California-Davis, Davis, CA 95616, USA; Department of Fisheries, Animal, and Veterinary Science, University of Rhode Island, Kingston, RI 02881, USA
| | - Julia D Fine
- Invasive Species and Pollinator Health Research Unit, USDA-ARS, 3026 Bee Biology Rd., Davis, CA 95616, USA
| | - Sascha C T Nicklisch
- Department of Environmental Toxicology, University of California-Davis, Davis, CA 95616, USA.
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Fine JD, Foster LJ, McAfee A. Indirect exposure to insect growth disruptors affects honey bee (Apis mellifera) reproductive behaviors and ovarian protein expression. PLoS One 2023; 18:e0292176. [PMID: 37782633 PMCID: PMC10545116 DOI: 10.1371/journal.pone.0292176] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 09/14/2023] [Indexed: 10/04/2023] Open
Abstract
Pesticide exposure and queen loss are considered to be major causes of honey bee colony mortality, yet little is known regarding the effects of regularly encountered agrochemicals on honey bee reproduction. Here, we present the results of a two-generational study using specialized cages to expose queens to commonly used insect growth disrupting pesticides (IGDs) via their retinue of worker bees. Under IGD exposure, we tracked queen performance and worker responses to queens, then the performance of the exposed queens' offspring was assessed to identify patterns that may contribute to the long-term health and stability of a social insect colony. The positive control, novaluron, resulted in deformed larvae hatching from eggs laid by exposed queens, and methoxyfenozide, diflubenzuron, and novaluron caused a slight decrease in daily egg laying rates, but this was not reflected in the total egg production over the course of the experiment. Curiously, eggs laid by queens exposed to pyriproxyfen exhibited increased hatching rates, and those larvae developed into worker progeny with increased responsiveness to their queens. Additionally, pyriproxyfen and novaluron exposure affected the queen ovarian protein expression, with the overwhelming majority of differentially expressed proteins coming from the pyriproxyfen exposure. We discuss these results and the potential implications for honey bee reproduction and colony health.
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Affiliation(s)
- Julia D. Fine
- Invasive Species and Pollinator Health Research Unit, USDA-ARS, Davis, CA, United States of America
| | - Leonard J. Foster
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Alison McAfee
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Applied Ecology, North Carolina State University, Raleigh, NC, United States of America
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Pineaux M, Grateau S, Lirand T, Aupinel P, Richard FJ. Honeybee queen exposure to a widely used fungicide disrupts reproduction and colony dynamic. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 322:121131. [PMID: 36709033 DOI: 10.1016/j.envpol.2023.121131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/07/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Pollinators have to cope with a wide range of stressful, not necessarily lethal factors limiting their performance and the ecological services they provide. Among these stressors are pesticides, chemicals that are originally designed to target crop-harming organisms but that also disrupt various functions in pollinators, including flight, communication, orientation and memory. Although all these functions are crucial for reproductive individuals when searching for mates or nesting places, it remains poorly understood how pesticides affect reproduction in pollinators. In this study, we investigated how a widely used fungicide, boscalid, affects reproduction in honey bees (Apis mellifera), an eusocial insect in which a single individual, the queen, fulfills the reproductive functions of the whole colony. Boscalid is a succinate dehydrogenase inhibitor (SDHI) fungicide mainly used on rapeseed flowers to target mitochondrial respiration in fungi but it is also suspected to disrupt foraging-linked functions in bees. We found that immature queen exposure to sublethal, field relevant doses of boscalid disrupted reproduction, as indicated by a dramatic increase in queen mortality during and shortly after the nuptial flights period and a decreased number of spermatozoa stored in the spermatheca of surviving queens. However, we did not observe a decreased paternity frequency in exposed queens that successfully established a colony. Queen exposure to boscalid had detrimental consequences on the colonies they later established regarding brood production, Varroa destructor infection and pollen storage but not nectar storage and population size. These perturbations at the colony-level correspond to nutritional stress conditions, and may have resulted from queen reduced energy provisioning to the eggs. Accordingly, we found that exposed queens had decreased gene expression levels of vitellogenin, a protein involved in egg-yolk formation. Overall, our results indicate that boscalid decreases honey bee queen reproductive quality, thus supporting the need to include reproduction in the traits measured during pesticide risk assessment procedures.
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Affiliation(s)
- Maxime Pineaux
- Unité Expérimentale d'Entomologie, INRAe, Le Magneraud, Surgères, France; Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions UMR CNRS 7267, Equipe Ecologie Evolution Symbiose, France.
| | - Stéphane Grateau
- Unité Expérimentale d'Entomologie, INRAe, Le Magneraud, Surgères, France
| | - Tiffany Lirand
- Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions UMR CNRS 7267, Equipe Ecologie Evolution Symbiose, France
| | - Pierrick Aupinel
- Unité Expérimentale d'Entomologie, INRAe, Le Magneraud, Surgères, France
| | - Freddie-Jeanne Richard
- Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions UMR CNRS 7267, Equipe Ecologie Evolution Symbiose, France.
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Goblirsch M, Adamczyk JJ. Using the Honey Bee (Apis mellifera L.) Cell Line AmE-711 to Evaluate Insecticide Toxicity. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:88-99. [PMID: 36263950 PMCID: PMC10107357 DOI: 10.1002/etc.5500] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/20/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
One of the main contributors to poor productivity and elevated mortality of honey bee colonies globally is insecticide exposure. Whole-organism and colony-level studies have demonstrated the effects of insecticides on many aspects of honey bee biology and have also shown their interactions with pathogens. However, there is a need for in vitro studies using cell lines to provide greater illumination of the effects of insecticides on honey bee cellular and molecular processes. We used a continuous cell line established from honey bee embryonic tissues (AmE-711) in assays that enabled assessment of cell viability in response to insecticide exposure. We exposed AmE-711 cells to four formulations, each containing a different insecticide. Treatment of cells with the insecticides resulted in a concentration-dependent reduction in viability after a 24-h exposure, whereas long-term exposure (120 h) to sublethal concentrations had limited effects on viability. The 24-h exposure data allowed us to predict the half-maximal lethal concentration (LC50) for each insecticide using a four-parameter logistical model. We then exposed cells for 12 h to the predicted LC50 and observed changes in morphology that would indicate stress and death. Reverse transcription-quantitative polymerase chain reaction analysis corroborated changes in morphology: expression of a cellular stress response gene, 410087a, increased after an 18-h exposure to the predicted LC50. Demonstration of the effects of insecticides through use of AmE-711 provides a foundation for additional research addressing issues specific to honey bee toxicology and complements whole-organism and colony-level approaches. Moreover, advances in the use of AmE-711 in high-throughput screening and in-depth analysis of cell regulatory networks will promote the discovery of novel control agents with decreased negative impacts on honey bees. Environ Toxicol Chem 2023;42:88-99. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Michael Goblirsch
- Thad Cochran Southern Horticultural Laboratory, Agricultural Research ServiceUS Department of AgriculturePoplarvilleMississippiUSA
| | - John J. Adamczyk
- Thad Cochran Southern Horticultural Laboratory, Agricultural Research ServiceUS Department of AgriculturePoplarvilleMississippiUSA
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Shpigler HY, Yaniv A, Gernat T, Robinson GE, Bloch G. The Influences of Illumination Regime on Egg-laying Rhythms of Honey Bee Queens. J Biol Rhythms 2022; 37:609-619. [PMID: 36226630 PMCID: PMC9727117 DOI: 10.1177/07487304221126782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Honey bee queens show extreme fecundity, commonly laying more than a thousand eggs in a single day. It has proven challenging to study the temporal organization of egg-laying behavior because queens are typically active around the clock in the dark cavity of a densely populated nest. To contend with this challenge, we developed two novel methods allowing detailed monitoring of queen activity and egg laying. We first adapted a high-resolution, continuous, tracking system allowing to track the position of barcode-tagged queens in observation hives with colonies foraging outside. We found that the queen is active ~96% of the day with typically no diurnal rhythm. Next, we developed a new laboratory procedure to monitor egg laying at single egg resolution under different light regimes. We found that under constant darkness (DD) and temperature conditions, queens laid eggs with no circadian rhythms. Queen fecundity was severely reduced under constant light (LL). Under a 12:12 illumination regime, queen fecundity was comparable to under constant darkness, with a higher number of eggs during the light phase. These daily rhythms in egg laying continued when these queens were released to DD conditions, suggesting that egg-laying rhythms are influenced by endogenous circadian clocks. These results suggest that honey bee queens are active and lay eggs around the clock with no diurnal rhythms. Light has complex influences on these behaviors, but more studies are needed to determine whether these effects reflect the influence of light directly on the queen or indirectly by affecting workers that interact with the queen.
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Affiliation(s)
- Hagai Y. Shpigler
- Department of Ecology, Evolution, and
Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University
of Jerusalem, Jerusalem, Israel,Carl R. Woese Institute for Genomic
Biology, University of Illinois Urbana–Champaign, Urbana, Illinois, USA,Department of Entomology, Agricultural
Research Organization, The Volcani Center, Rishon LeZion, Israel,Hagai Y. Shpigler,
Department of Entomology, Agricultural Research Organization, The Volcani
Center, Rishon LeZion, Israel; e-mail:
| | - Almog Yaniv
- Department of Ecology, Evolution, and
Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University
of Jerusalem, Jerusalem, Israel
| | - Tim Gernat
- Carl R. Woese Institute for Genomic
Biology, University of Illinois Urbana–Champaign, Urbana, Illinois, USA
| | - Gene E. Robinson
- Carl R. Woese Institute for Genomic
Biology, University of Illinois Urbana–Champaign, Urbana, Illinois, USA,Entomology Department, University of
Illinois Urbana–Champaign, Urbana, Illinois, USA,Neuroscience Program, University of
Illinois Urbana–Champaign, Urbana, Illinois, USA
| | - Guy Bloch
- Department of Ecology, Evolution, and
Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University
of Jerusalem, Jerusalem, Israel,Guy Bloch, Department of
Ecology, Evolution, and Behavior, The Alexander Silberman Institute of Life
Sciences, The Hebrew University of Jerusalem, Berman 114, Jerusalem 9190401,
Israel; e-mail:
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St. Clair AL, Suresh S, Dolezal AG. Access to prairie pollen affects honey bee queen fecundity in the field and lab. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.908667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Beekeepers experience high annual losses of colonies, with environmental stressors like pathogens, reduced forage, and pesticides as contributors. Some factors, like nutritional stress from reduced flower abundance or diversity, are more pronounced in agricultural landscapes where extensive farming limits pollen availability. In addition to affecting other aspects of colony health, quantity and quality of pollen available are important for colony brood production and likely for queen egg laying. While some US beekeepers report >50% of colony loss due to queen failure, the causes of poor-quality queens are poorly understood. Access to resources from native prairie habitat is suggested as a valuable late-season resource for honey bees that can reverse colony growth declines, but it is not clear how prairie forage influences queen egg laying. We hypothesized that the pollen resources present in an extensive Midwestern corn/soybean agroecosystem during the critical late season period affect honey bee queen egg laying and that access to native prairies can increase queen productivity. To test this, we designed a field experiment in Iowa, keeping colonies in either soybean or prairie landscapes during a critical period of forage dearth, and we quantified queen egg laying as well as pollen collection (quantity and species). Then, using pollen collected in the field experiments, we created representative dietary mixtures, which we fed to bees using highly controlled laboratory cages to test how consumption of these diets affected the egg laying of naive queens. In two out of three years, queens in prairies laid more eggs compared to those in soybean fields. Pollen quantity did not vary between the two landscapes, but composition of species did, and was primarily driven by collection of evening primrose (Oenothera biennis). When pollen representative of the two landscapes was fed to caged bees in the laboratory queens fed prairie pollen laid more eggs, suggesting that pollen from this landscape plays an important role in queen productivity. More work is needed to tease apart the drivers of these differences, but understanding how egg laying is regulated is useful for designing landscapes for sustainable pollinator management and can inform feeding regimes for beekeepers.
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He Q, Yang Q, Liu Q, Hu Z, Gao Q, Dong Y, Xiao J, Yu L, Cao H. The effects of beta-cypermethrin, chlorbenzuron, chlorothalonil, and pendimethalin on Apis mellifera ligustica and Apis cerana cerana larvae reared in vitro. PEST MANAGEMENT SCIENCE 2022; 78:1407-1416. [PMID: 34897947 DOI: 10.1002/ps.6757] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 11/26/2021] [Accepted: 12/12/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Declines in bee populations and diversity have drawn international attention. The long-term use of chemical pesticides has affected bee behavior and physiology. This study aimed to investigate the effects of chronic exposure to four commonly used chemical pesticides (beta-cypermethrin, chlorbenzuron, chlorothalonil and pendimethalin) on the growth of Apis mellifera ligustica and Apis cerana cerana larvae reared in vitro. RESULTS Pesticide type and concentration were the main factors affecting honeybee fitness. Beta-cypermethrin and chlorbenzuron had chronic toxic effects on bee larvae. They reduced the fitness of A. m. ligustica and A. c. cerana even at low doses of 323.5 ng g-1 for beta-cypermethrin and 62.6 ng g-1 for chlorbenzuron in bee bread. The effects were positively associated with the dietary amounts of pesticides. By contrast, chlorothalonil and pendimethalin exposure did not affect bee larvae despite changes in enzyme activities. Caution is still needed with chlorothalonil, which led to a decrease in harvest adult bee numbers at a high dose (6937.2 ng g-1 ). Furthermore, a difference in pesticide resistance was observed, suggesting that A. m. ligustica may tolerate toxic effects better than A. c. cerana. CONCLUSION This study sheds new light on chronic toxicity in bee larvae exposed to residues in bee bread. The results could guide the scientific and rational use of chemical pesticides to reduce the potential risks to A. m. ligustica and A. c. cerana. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Qibao He
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Qing Yang
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Qiongqiong Liu
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Zhaoyin Hu
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Quan Gao
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Yongcheng Dong
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Jinjing Xiao
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Linsheng Yu
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Haiqun Cao
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, China
- Anhui Province Key Laboratory of Crop Integrated Pest Management, School of Plant Protection, Anhui Agricultural University, Hefei, China
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Indirect transfer of pyriproxyfen to European honeybees via an autodissemination approach. PLoS Negl Trop Dis 2021; 15:e0009824. [PMID: 34648501 PMCID: PMC8516248 DOI: 10.1371/journal.pntd.0009824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 09/20/2021] [Indexed: 11/19/2022] Open
Abstract
The frequency of arboviral disease epidemics is increasing and vector control remains the primary mechanism to limit arboviral transmission. Container inhabiting mosquitoes such as Aedes albopictus and Aedes aegypti are the primary vectors of dengue, chikungunya, and Zika viruses. Current vector control methods for these species are often ineffective, suggesting the need for novel control approaches. A proposed novel approach is autodissemination of insect growth regulators (IGRs). The advantage of autodissemination approaches is small amounts of active ingredients compared to traditional insecticide applications are used to impact mosquito populations. While the direct targeting of cryptic locations via autodissemination seems like a significant advantage over large scale applications of insecticides, this approach could actually affect nontarget organisms by delivering these highly potent long lasting growth inhibitors such as pyriproxyfen (PPF) to the exact locations that other beneficial insects visit, such as a nectar source. Here we tested the hypothesis that PPF treated male Ae. albopictus will contaminate nectar sources, which results in the indirect transfer of PPF to European honey bees (Apis mellifera). We performed bioassays, fluorescent imaging, and mass spectrometry on insect and artificial nectar source materials to examine for intra- and interspecific transfer of PPF. Data suggests there is direct transfer of PPF from Ae. albopictus PPF treated males and indirect transfer of PPF to A. mellifera from artificial nectar sources. In addition, we show a reduction in fecundity in Ae. albopictus and Drosophila melanogaster when exposed to sublethal doses of PPF. The observed transfer of PPF to A. mellifera suggests the need for further investigation of autodissemination approaches in a more field like setting to examine for risks to insect pollinators. Autodissemination approaches have attracted a significant amount of attention for mosquito control because of the advantages of self-delivery of small amounts of highly potent insect growth regulators (IGRs) such as pyriproxyfen (PPF) to oviposition locations. However, while PPF may be delivered to oviposition locations by the mosquito vehicles, these treated mosquitoes may also be delivering PPF to nectar sources that other insects may visit, in particular important insect pollinators. Here we have examined for the direct transfer of PPF to nectar sources and the indirect transfer to the European honey bee. We show PPF is being deposited on artificial nectar sources and is being indirectly transferred to European honey bees. The results are discussed in reference to the potential risks to important insect pollinators of using autodissemination approaches for mosquito control.
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Walsh EM, Khan O, Grunseich J, Helms AM, Ing NH, Rangel J. Pesticide Exposure During Development Does Not Affect the Larval Pheromones, Feeding Rates, or Morphology of Adult Honey Bee (Apis mellifera) Queens. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.681506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Recent work demonstrated that honey bee (Apis mellifera L.) queens reared in pesticide-laden beeswax exhibit significant changes in the composition of the chemicals produced by their mandibular glands including those that comprise queen mandibular pheromone, which is a critical signal used in mating as well as queen tending behavior. For the present study, we hypothesized that pesticide exposure during development would alter other queen-produced chemicals, including brood pheromone in immature queens, thus resulting in differential feeding of queen larvae by nurse workers, ultimately impacting adult queen morphology. We tested these hypotheses by rearing queens in beeswax containing field-relevant concentrations of (1) a combination of tau-fluvalinate and coumaphos, (2) amitraz, or (3) a combination of chlorothalonil and chlorpyrifos. These pesticides are ubiquitous in most commercial beekeeping operations in North America. We observed nurse feeding rates of queen larvae grafted into pesticide-laden beeswax, analyzed the chemical composition of larval queen pheromones and measured morphological markers in adult queens. Neither the nurse feeding rates, nor the chemical profiles of immature queen pheromones, differed significantly between queens reared in pesticide-laden wax compared to queens reared in pesticide-free wax. Moreover, pesticide exposure during development did not cause virgin or mated adult queens to exhibit differences in morphological markers (i.e., body weight, head width, or thorax width). These results were unexpected given our previous research and indicate that future work is needed to fully understand how pesticide exposure during development affects honey bee queen physiology, as well as how various adult queen quality metrics relate to each other.
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