Queenless Colonies Research Articles

The Honey Bee Colony's Criterion for Candidate Selection: "Ongoing" or "One-Shot"?

In the honey bee, the queen's death severely threatens the survival of the colony. In an emergency, new queens are reared from young worker larvae, where nepotism is thought to influence the choice of queen candidates by the workers. This article simulates the emergency queen-rearing process in a colony under natural conditions and records the results of colony selection (without nepotism). In queenless colonies, worker larvae aged three days or younger were preferred for queen rearing, and 1-day-old larvae were the first to be selected for the queen-cell cups. In the capping stage, the number of capped queen cells selected from the 1-day-old larvae was much higher than the 3-day-old larvae. On the first day, the number of emerging queens reared from 1-day-old larvae was significantly higher than the queens reared from 2-day-old and 3-day-old larvae. However, there was no significant difference in the birth weights of queens reared from 1-day-old, 2-day-old, or 3-day-old larvae. When the newly emerged queens were introduced into the original queenless colony, 1-day-old larval queens triggered more worker followers than 2-day-old larval queens. The expression of ovarian development-related genes (vg, hex110, and Jh) was higher in queens reared from 1-day-old larvae than those reared from 2-day-old and 3-day-old larvae, indicating that the quality of the queens reared from 1-day-old larvae is superior. This study shows that in the absence of nepotism, the colony selection of queen candidates at the larval stage, capping stage, and emerging stage is not final, but is gradually optimized to maximize colony development through a "quality control" process.

The Effect of Production Method on Local Honeybee Queens, Apis mellifera L. to Determine the Acceptance Rate of Grafted Larvae and Live Weight of Virgin Queens in Latakia Governorate

Asaad, M., M. Omran, N.Z. Hujeij and K. Makis. 2024. The Effect of Production Method on Local Honeybee Queens, Apis mellifera L. to Determine the Acceptance Rate of Grafted Larvae and Live Weight of Virgin Queens in Latakia Governorate. Arab Journal of Plant Protection, 42(2): 155-161. https://doi.org/10.22268/AJPP-001239 This research was conducted at the Scientific Agricultural Research Center in Latakia during 2020 season to study the effect of queen production method (with and without queens) on the acceptance rate of grafted larvae and weight of virgin queens emerging from local bee colonies under the Syrian coast conditions, using wax and plastic cups with dry and wet grafting. The acceptance rate of larvae was 83.33 and 91.66%, and weights of virgin queens were 0.178, 0.198 g in queen rearing colonies with and without queens, respectively, in the wax cups with wet grafting and with a total number of 16 cups/colony, whereas the acceptance rate of larvae was 86.66 and 80.00 % and weights of virgin queens was 0.178 and 0.169 g, respectively, in colonies without or with restricted queens rearing colonies, in the wax cups with wet grafting and a total number of 20 cups/colony. The difference in the average weights of queens in both methods was significant. Keywords: Colonies with queens, queenless colonies, bees, Latakia, Syria.

Decoding the Behavior of a Queenless Colony Using Sound Signals.

Honeybees are reported to be the most vital pollinators of agricultural and horticultural crops. However, their widespread decline has raised great attention to the need to monitor their activity in order to identify the causes and implement countermeasures. The recording and analysis of signals used by honeybees for their communication in their hive can be a very helpful tool to the beekeepers for the remote control of the hives. Thus, in the present study, we used a set of sound recording data taken inside the hives to automatically detect the sounds of the bees over a certain period, to distinguish between queenright and queenless states, and to find the gradual changes in the queenless state. Unlike what was commonly believed, noticeable changes in the sound signals of all experimental colonies were observed just one hour after the queens' removal from the hive, while the sound signals were intensified over a period of 5 h, after which the transmitted signal stabilized to the equivalent of a queenless state. The colonies seemed to return to their normal sounds 9-10 days after the reintroduction of the queens in the hives. Our study concluded that timely intervention of the queen's absence combined with the immediate intervention of the beekeeper may be a determining factor in mitigating the adverse effects that occur from the queen's loss.

Requeening queenright honey bee colonies with queen cells in honey supers.

Many Canadian beekeepers replace a subset of their honey bee queens annually. However, introducing a new queen to a honey bee colony is a management practice with a high degree of uncertainty. Despite the consensus that it is most effective to introduce queens to queenless colonies, some commercial beekeepers claim success with introducing queen cells into the honey super of queenright colonies. We tested the success rate of this practice by introducing queen cells to 100 queenright colonies in southern Alberta during a honey flow. The genotypes of the resultant offspring drones were determined using the microsatellite marker A76 to identify their laying queen mothers. Our results show that new queens successfully supersede original queens in 6% of queenright colonies, suggesting that the practice does not result in the new queen taking over leadership in most colonies. Additionally, supersedure by daughter queens is more common (13%) than new queen supersedure when introducing queen cells to queenright colonies during a honey flow. However, there could be a benefit to the practice of requeening queenright colonies with queen cells in honey supers if the colonies that accepted a new queen (whether a daughter of or unrelated to the old queen) were colonies with a failing queen.

Worker Reproduction in the Highly Polygynous Ant Crematogaster pygmaea Forel, 1904 (Hymenoptera: Formicidae)

In most ant species, workers have retained functional ovaries, allowing them to potentially lay viable unfertilized eggs that develop into males. Mechanisms (ex.: queen and/or worker policing) have nevertheless evolved to control worker reproduction when the queen is present. In many species with a high degree of polygyny, especially in tramp species, complete sterility of workers has evolved, presumably to “trap” them within their “worker phenotype”. Our study showed for the first time that in the highly polygynous and polydomous ant Crematogaster pygmaea, workers retained the full capacity to produce reproductive eggs in queenless colonies, with at least some of them developing in adult males. We provide evidence that worker-produced males are reproductively functional. Although most queenless colonies produced eggs, few larvae developed into pupae and adult males. We conclude that workers strongly police the worker-produced offspring, even in the queen's absence. Probable high relatedness between queens of C. pygmaea colonies and strong genetic proximity between brood and workers could force the workers in their helper, non-reproductive function even if they keep the ability to reproduce. Our observations indicate that the production of adult males and gynes in C. pygmaea is controlled by seasonal factors related to the rainy season.

Honey Bee Colony Losses in Mexico’s Semi-Arid High Plateau for the Winters 2016–2017 to 2021–2022

The objective of this study was to estimate the loss rates of honey bee (Apis mellifera) colonies in six consecutive winters (2016-2017 to 2021-2022) in five states of the semi-arid high plateau region of Mexico, as well as study the factors associated with these losses. The survey included data from 544 beekeepers and 75,341 colonies. The colony loss rate differs significantly (p < 0.0001) between the winters analyzed and fluctuates between 14.9% and 30%, with an average of 22%. Colony losses were unaffected (p > 0.05) by migratory beekeeping practice and operation size, but losses were significantly affected by Varroa monitoring and control (p ≤ 0.001). The types of loss differ among the winters analyzed. In the winters of 2016-2017 to 2018-2019, beekeepers attributed higher loss rates to unresolved problems related to the queen (e.g., a queenless colony, poor laying), but in the winters of 2019-2020 to 2021-2022, the highest loss rate was the result of problems such as diseases, poisoning, and absconding (leading to dead colonies or empty hives). The results reveal high loss rates in the region studied, as reported by beekeepers from other countries. It is suggested that strategies should be implemented to improve the quality of queens, the control of varroasis and other diseases, and the degree of Africanization.

The effects of different industrial sugars on royal jelly production

In this study, the larvae acceptance rate and the royal jelly yield in honeybee (Apis mellifera L.) colonies supplemented with different industrial sugars at different locations were determined. For this purpose, feeding groups (1. Sucrose group, 2. Glucose group, 3. Bee feed syrup group, 4. Control group) and locations (1. Battalgazi, 2. Doğanşehir) were formed. In queenless colonies that produce royal jelly, in order to sustain 5-15 day-old young feeder worker bees, two sealed frames with brood from support colonies were added. The royal jelly yield was harvested seven times. Based on the location, the feeding groups, and the location x feeding groups interaction, 12600 larvae were grafted, 9054 larvae were accepted, and the larvae acceptance rate was determined as 71.86%. Based on the location, feeding groups and the location x feeding group interaction, the yield per cell was calculated as 213.15 ± 11.53 mg/cell, the yield per colony as 6.88 ± 0.38 g/col./app., and the total yield per colony as 34.40 ± 1.91 g/colony. In the study, no statistically significant difference was determined between feeding with sucrose, bee feed and the supplementary feeding with glucose. On the other hand, it was determined that the location where the royal jelly was produced affected both the larvae acceptance and the royal jelly yield.

Intra-colony venom diversity contributes to maintaining eusociality in a cooperatively breeding ant

BackgroundEusociality is widely considered to evolve through kin selection, where the reproductive success of an individual’s close relative is favored at the expense of its own. High genetic relatedness is thus considered a prerequisite for eusociality. While ants are textbook examples of eusocial animals, not all ants form colonies of closely related individuals. One such example is the ectatommine ant Rhytidoponera metallica, which predominantly forms queen-less colonies that have such a low intra-colony relatedness that they have been proposed to represent a transient, unstable form of eusociality. However, R. metallica is among the most abundant and widespread ants on the Australian continent. This apparent contradiction provides an example of how inclusive fitness may not by itself explain the maintenance of eusociality and raises the question of what other selective advantages maintain the eusocial lifestyle of this species.ResultsWe provide a comprehensive portrait of the venom of R. metallica and show that the colony-wide venom consists of an exceptionally high diversity of functionally distinct toxins for an ant. These toxins have evolved under strong positive selection, which is normally expected to reduce genetic variance. Yet, R. metallica exhibits remarkable intra-colony variation, with workers sharing only a relatively small proportion of toxins in their venoms. This variation is not due to the presence of chemical castes, but has a genetic foundation that is at least in part explained by toxin allelic diversity.ConclusionsTaken together, our results suggest that the toxin diversity contained in R. metallica colonies may be maintained by a form of group selection that selects for colonies that can exploit more resources and defend against a wider range of predators. We propose that increased intra-colony genetic variance resulting from low kinship may itself provide a selective advantage in the form of an expanded pharmacological venom repertoire. These findings provide an example of how group selection on adaptive phenotypes may contribute to maintaining eusociality where a prerequisite for kin selection is diminished.

Asymmetry in the ovarioles, mandibular glands and hypopharyngeal glands of honeybee (Apis mellifera) workers developing in queenright or queenless colonies

Asymmetry in the ovarioles, mandibular glands and hypopharyngeal glands of honeybee (Apis mellifera) workers developing in queenright or queenless colonies

Determination of total protein, trans- 10-Hydroxy-2-Decenoic Acid (10-HDA) and major royal jelly proteins in royal jelly produced at different harvest times in queenless and queenright colonies

Two of the most important ingredients to add functional properties to royal jelly are 10-HDA and major royal jelly proteins (MRJPs). The effect of royal jelly (RJ) production and the effect of royal jelly harvest time (24, 48 and 72 hours) on 10-HDA, the total protein content of RJ, and molecular weights of major proteins in RJ were investigated in queenright and queenless colonies. RJ production colonies were divided into 2 groups as queenless and queenright where the queen was confined with frames. Subgroups were formed within each group (queenless and queenright) according to harvest time (24, 48 and 72 hours). 80 larvae were transferred to each colony. In this study, as the harvest time increased, total protein (TP) ratio decreased (p&amp;lt;0.05); TP ratio in RJs harvested at 24, 48 and 72 hours was determined as 18.4±1.24%, 15.2±0.80%, 10.6±0.27%, respectively. As the harvest time increased, 10-HDA decreased. It was determined 10-HDA rates in RJ harvested at 24, 48 and 72 hours respectively; 2.52±0.109%, 2.20±0.110%, 2.00±0.112%. MRJP1, MRJP2, MRJP3 and MRJP5 were found from the MRJP family, and their molecular weights were determined as 53 kDa, 46.5 kDa, 66.8 kDa, 80.9 kDa, respectively. As a result, the early harvested (24 and 48 hours) RJ had higher values in terms of TP and trans 10-HDA than the royal jelly harvested at 72 hours.

Ovary activation correlates with the reproductive potential of honeybee (Apis mellifera) workers if they are in a foreign colony

In eusocial Hymenoptera, the laying of male-determined eggs by workers in an unrelated colony can be a powerful strategy for increasing direct fitness benefits. A recent study showed that honeybee rebels, which are workers that develop under queenless conditions and have high reproductive potential, drift to foreign colonies, with a preference for hopelessly queenless colonies, and act as reproductive parasites. In our experiment, by introducing 5-day-old rebels and normal workers into foreign queenright colonies, we discovered that only rebels developed a reproductive phenotype by activating their ovaries. In a similar experiment with 1-day-old workers, neither rebels nor normal workers displayed such a tendency. We suggest that workers’ reproductive potential could thus be a key parameter activating the ovaries in not only drifting workers but also workers acting as reproductive parasites. Our results also support the hypothesis that the colony recognition cue probably has an environmental, rather than a genetic, origin.

Bee‐associated fungi mediate effects of fungicides on bumble bees

AbstractBumble bees are important pollinators that face threats from multiple sources, including agrochemical application. Declining bumble bee populations have been linked to fungicide application, which could directly affect the fungi often found in the stored food and gastrointestinal (GI) tract of healthy bumble bees.We test the hypothesis that fungicides impact bee health by disrupting bee–fungi interactions. We examined the interactive effects of the fungicide propiconazole and fungal supplementation on the survival, reproduction and microbiome composition of microcolonies (queenless colonies) using two species,Bombus vosnesenskiiandB. impatiens.We found that inB. vosnesenskii, fungicide exposure decreased survival, while fungal supplementation mitigated fungicide effects. ForB. impatiens, fungicide application had no effect, but fungal supplementation improved survival and offspring production.Fungicides reduced fungal abundance inB. vosnesenskiimicrocolonies, but not inB. impatiens, where instead fungal addition decreased fungal abundance (ITS copy number). Fungal composition varied between treatments but differently between bee species. InB. impatiens, fungal addition increased microbiome diversity. InB. vosnesenskii, the abundance of the pathogenAscosphaerawas negatively associated with survival, while the yeastZygosaccharomyceswas positively associated with survival.Our results highlight that bumble bee species differ in response to fungicides and in the nature of bee‐fungi associations. Fungicides can alter bee–fungi interactions with consequences for bee survival and reproduction, and exploring the mechanisms of such interactions, including interactions among fungi in the bee GI tract, may offer insights into bumble bee biology and conservation strategies.

Histone acetylation regulates the expression of genes involved in worker reproduction in the ant Temnothorax rugatulus

BackgroundIn insect societies, queens monopolize reproduction while workers perform tasks such as brood care or foraging. Queen loss leads to ovary development and lifespan extension in workers of many ant species. However, the underlying molecular mechanisms of this phenotypic plasticity remain unclear. Recent studies highlight the importance of epigenetics in regulating plastic traits in social insects. Thus, we investigated the role of histone acetylation in regulating worker reproduction in the ant Temnothorax rugatulus. We removed queens from their colonies to induce worker fecundity, and either fed workers with chemical inhibitors of histone acetylation (C646), deacetylation (TSA), or the solvent (DMSO) as control. We monitored worker number for six weeks after which we assessed ovary development and sequenced fat body mRNA.ResultsWorkers survived better in queenless colonies. They also developed their ovaries after queen removal in control colonies as expected, but not in colonies treated with the chemical inhibitors. Both inhibitors affected gene expression, although the inhibition of histone acetylation using C646 altered the expression of more genes with immunity, fecundity, and longevity functionalities. Interestingly, these C646-treated workers shared many upregulated genes with infertile workers from queenright colonies. We also identified one gene with antioxidant properties commonly downregulated in infertile workers from queenright colonies and both C646 and TSA-treated workers from queenless colonies.ConclusionOur results suggest that histone acetylation is involved in the molecular regulation of worker reproduction, and thus point to an important role of histone modifications in modulating phenotypic plasticity of life history traits in social insects.

Reproductive Potential Accelerates Preimaginal Development of Rebel Workers in Apis mellifera.

Simple SummaryAll female honeybee larvae may develop into workers or queens, depending on the food they receive. During this period, queen mandibular pheromones (QMP) perform a regulatory function in inhibiting ovarian development in adult workers. These pheromones are transmitted (via trophallaxis) by workers to pass information to larvae on the presence or absence of the queen. Queen-less conditions are conducive to the emergence of rebel workers that are set to reproduce, and do not participate in the rearing of successive bee generations in contrast to the sterile, normal workers. We posited that rebels are not only similar to queens in some anatomical features, but also develop in a shorter time in comparison to normal workers. Therefore, the aim of this study was to compare the duration of preimaginal development in rebel and normal workers. Our results confirmed that the workers who develop in a queen-less colony undergo a shorter preimaginal development than those in a queen-right colony.Rebel workers develop from eggs laid by the previous queen, before it went swarming and left the colony orphaned, until the emergence of a new queen. In contrast to normal workers developing in the queen’s presence, rebels are set to reproduce and avoid rearing of successive bee generations. They have more ovarioles in their ovaries, as well as more developed mandibular glands and underdeveloped hypopharyngeal glands, just like the queen. We posited that rebels are not only similar to queens in some anatomical features, but also develop in a shorter time in comparison to normal workers. Therefore, the aim of this study was to compare preimaginal development duration in rebel and normal workers. The results show that rebels, i.e., workers with a higher reproductive potential, had a significantly shorter preimaginal development period (mean ± SD, 19.24 ± 0.07 days) than normal workers (22.29 ± 0.32 days). Our result confirmed that workers who develop in a queen-less colony undergo a shorter preimaginal development than those in a queen-right colony.

The Effect of Climate and Diet on Body Lipid Composition in the Oriental Hornet (Vespa orientalis)

Fatty acids (FA) are the primary metabolic fuel for many organisms and the fundamental component of membranes of all living organisms. FAs can be saturated (SFA), monounsaturated (MUFA), or polyunsaturated (PUFA). PUFA are not synthesized by most animals and are considered as essential nutrients. We examined the effect of climate on the saturation level of polar (mostly membranal) and neutral lipids in the body of the Oriental hornet (Vespa orientalis) from two extreme climatic zones: Mediterranean high elevation; and hot arid desert. In contrast to previous reports, the environmental temperature was shown to affect the hornet colonies’ thermal environments. The hornets nonetheless maintained their colony temperature within a narrow range. Analyses of the hornets’ unsaturation levels of polar and non-polar body lipids revealed caste differences: gynes and males contained less unsaturated lipids than workers. However, there were no differences in the respective castes between the two different climate zones tested. Experimentally manipulating the diet of queenless hornet colonies to a high Omega-3 diet (salmon) or a high Omega-6 diet (crickets) had only a minor effect on the worker-born males’ lipid composition. Although salmon-fed males had a higher Omega-3 content than cricket-fed ones, the proportion of these fatty acids was still low (below 1%). Cricket-fed males had significantly higher levels of Omega-6 than salmon-fed males. Our data show that the specific lipid composition of the hornet body is highly regulated and deficient in essential PUFA, even under different climates or high Omega-3 or Omega-6 PUFA diet. PUFA, especially Omega-3, is considered to have a beneficial effect on physiological processes. Our finding that these FA, when common in the diet, are almost absent in the body raises questions about how they affect animals’ physiology.

Does the Presence and Absence of Queen Bee in the Production of Royal Jelly Affect the Amount of Soluble Protein and Ratio of 10-Hydroxy-2-Decenoic Acid?

Royal jelly (RJ), is one of the important honey bee products and a functional food item in the regulation of diets and in the cosmetic industry. RJ has a potential towards various human disease treatments. The chemical content of RJ is influenced by some factors. In this study, the effect of the presence or absence of the queen on the amount of 10-hydroxy-2-decenoic acid (10-HDA) and soluble protein in RJ is determined. For this reason, colonies were prepared as queenless, queenright and starter-finisher. RJ yields in colonies queenless, queenright and starter-finisher were determined as 15.2 ± 0.89 g, 12.0 ± 0.90 g and 9.6 ± 0.72 g, respectively. Group queenless was different from the other two groups. While 10-HDA values of the groups were similar (queenless, queenright and starter-finisher, respectively; 2.0 ± 0.06%, 2.1 ± 0.06% and 2.0 ± 0.05%), the soluble protein amounts of the groups (queenless, queenright and starter-finisher, respectively, 9.65 ± 0.179%, 7.68 ± 0.184%, 7.50 ± 0.203%) were found different and significant from each other. As a result, the RJ production colony queenless or queenright affected the amount of soluble protein. The worker bees of queenless colonies secreted RJ containing more soluble protein.

DNA methylation is not a driver of gene expression reprogramming in young honey bee workers.

The presence of DNA methylation marks within genic intervals, also called gene body methylation, is an evolutionarily-conserved epigenetic hallmark of animal and plant methylomes. In social insects, gene body methylation is thought to contribute to behavioural plasticity, for example between foragers and nurse workers, by modulating gene expression. However, recent studies have suggested that the majority of DNA methylation is sequence-specific, and therefore cannot act as a flexible mediator between environmental cues and gene expression. To address this paradox, we examined whole-genome methylation patterns in the brains and ovaries of young honey bee workers that had been subjected to divergent social contexts: the presence or absence of the queen. Although these social contexts are known to bring about extreme changes in behavioral and reproductive traits through differential gene expression, we found no significant differences between the methylomes of workers from queenright and queenless colonies. In contrast, thousands of regions were differentially methylated between colonies, and these differences were not associated with differential gene expression in the subset of genes examined. Methylation patterns were highly similar between brain and ovary tissues and only differed in nine regions. These results strongly indicate that DNA methylation is not a driver of differential gene expression between tissues or behavioral morphs. Finally, despite the lack of difference in methylation patterns, queen presence affected the expression of all four DNA methyltransferase genes, suggesting that these enzymes have roles beyond DNA methylation. Therefore, the functional role of DNA methylation in social insect genomes remains an open question.

Low Virulence of the Fungi Escovopsis and Escovopsioides to a Leaf-Cutting Ant-Fungus Symbiosis.

Eusocial insects interact with a diversity of parasites that can threaten their survival and reproduction. The amount of harm these parasites cause to their hosts (i.e., their virulence) can be influenced by numerous factors, such as the ecological context in which the parasite and its host are inserted. Leaf-cutting ants (genera Atta, Acromyrmex and Amoimyrmex, Attini: Formicidae) are an example of a eusocial insect whose colonies are constantly threatened by parasites. The fungi Escovopsis and Escovopsioides (Ascomycota: Hypocreales) are considered a highly virulent parasite and an antagonist, respectively, to the leaf-cutting ants’ fungal cultivar, Leucoagaricus gongylophorus (Basidiomycota: Agaricales). Since Escovopsis and Escovopsioides are common inhabitants of healthy colonies that can live for years, we expect them to have low levels of virulence. However, this virulence could vary depending on ecological context. We therefore tested two hypotheses: (i) Escovopsis and Escovopsioides are of low virulence to colonies; (ii) virulence increases as colony complexity decreases. For this, we used three levels of complexity: queenright colonies (fungus garden with queen and workers), queenless colonies (fungus garden and workers, without queen) and fungus gardens (without any ants). Each was inoculated with extremely high concentrations of conidia of Escovopsis moelleri, Escovopsioides nivea, the mycoparasitic fungus Trichoderma longibrachiatum or a blank control. We found that these fungi were of low virulence to queenright colonies. The survival of queenless colonies was decreased by E. moelleri and fungus gardens were suppressed by all treatments. Moreover, E. nivea and T. longibrachiatum seemed to be less aggressive than E. moelleri, observed both in vivo and in vitro. The results highlight the importance of each element (queen, workers and fungus garden) in the leaf-cutting ant-fungus symbiosis. Most importantly, we showed that Escovopsis may not be virulent to healthy colonies, despite commonly being described as such, with the reported virulence of Escovopsis being due to poor colony conditions in the field or in laboratory experiments.

Segmentation of the subcuticular fat body in Apis mellifera females with different reproductive potentials

Evolution has created different castes of females in eusocial haplodiploids. The difference between them lies in their functions and vulnerability but above all in their reproductive potentials. Honeybee queens are highly fertile. On the other hand, the workers are facultatively sterile. However, rebel workers, i.e. workers that develop in a queenless colony, reproduce more often than normal workers. As a result, the fat body of these bees, which apart from acting as the energy reserve, is also the site of numerous metabolic processes, had to specialize in different functions perfected over millions of years of eusocial evolution. Assuming that the variety of functions manifests itself in the pleomorphic structure of the fat body cells, we predicted that also different parts of the fat body, e.g. from different segments of the abdomen, contain different sets of cells. Such differences could be expected between queens, rebels and normal workers, i.e. females with dramatically different reproductive potentials. We confirmed all these expectations. Although all bees had the same types of cells, their proportion and segmental character corresponded with the caste reproductive potential and physiological characteristics shaped in the evolutionary process. The females with an increased reproductive potential were characterized by the presence of oenocytes in the third tergite and high concentrations of compounds responsible for energy reserves, like glucose, glycogen and triglycerides. Queens had very large trophocytes, especially in the third tergite. Only in workers did we observe intercellular spaces in all the segments of the fat body, as well as high protein concentrations—especially in the sternite. As expected, the rebels combined many features of the queens and normal workers, what with other findings can help understand the ways that led to the origin of different castes in females of eusocial Hymenoptera.

Successful Indoor Mass Storage of Honeybee Queens (Apis mellifera) during Winter

The production of young, mated honeybee queens (Apis mellifera) is essential to replace dead queens or to start new colonies after wintering. Mass storage of mated honeybee queens during winter and their use the following spring is an interesting strategy that could help fulfill this need. In this study, we investigated the survival, fertility, and fecundity of young, mated queens stored massively in queenless colonies from September to April (eight months). The queens were kept in environmentally controlled rooms at temperatures above and below cluster formation. The results show that indoor mass storage of mated queens can be achieved with success when queen banks are stored above cluster temperature. Significantly higher survival of queens was measured when wintering queen banks at 16 °C. Surviving queens wintered at different temperatures above or below cluster formation had similar fertility (sperm viability) and fecundity (egg laying and viable worker population). This study shows the potential of indoor overwintering of honeybee queen banks. The technique we describe could be applied on a commercial scale by beekeepers and queen breeders.