Honey Bee Species Research Articles

Why, when and where did honey bee dance communication evolve?

Honey bees (Apis sp.) are the only known bee genus that uses nest-based communication to provide nest-mates with information about the location of resources, the so-called “dance language.” Successful foragers perform waggle dances for high quality food sources and suitable nest-sites during swarming. However, since many species of social insects do not communicate the location of resources to their nest-mates, the question of why the dance language evolved is of ongoing interest. We review recent theoretical and empirical research into the ecological circumstances that make dance communication beneficial in present day environments. This research suggests that the “dance language” is most beneficial when food sources differ greatly in quality and are hard to find. The dances of extant honey bee species differ in important ways, and phylogenetic studies suggest an increase in dance complexity over time: species with the least complex dance were the first to appear and species with the most complex dance are the most derived. We review the fossil record of honey bees and speculate about the time and context (foraging vs. swarming) in which spatially referential dance communication might have evolved. We conclude that there are few certainties about when the “dance language” first appeared; dance communication could be older than 40 million years and, thus, predate the genus Apis, or it could be as recent as 20 million years when extant honey bee species diverged during the early Miocene. The most parsimonious scenario assumes it evolved in a sub-tropical to temperate climate, with patchy vegetation somewhere in Eurasia.

An overview of Beekeeping Economy and Its Constraints in Nepal

Beekeeping has been in practice from an ancient time in Nepal. It is one of the high valued and income-generating activities for the people in Nepal. Diverse climatic conditions of Nepal harbor five species of honeybee out of which Apis laboriosa, A. dorsata, A. cerena, A. florea are native, whereas Apis mellifera was introduced and is being reared commercially. Three sub-species of A. cerana, viz. A. cerana indica, A. cerana himalaya and A. cerana cerana are distributed in different regions of Nepal. A. cerena is cultivated in traditional log hive as well as in modern bee hive. However, most of the annual honey production comes from wild honeybees. Number of hives recorded during 2012/13 was 169,000 with 1625 metric tons of honey production. Hive productivity is low due to problems associated with apiculture; low quality management of bees, colony migration and absconding, pesticide intoxication, product quality control, inadequate data on bee floral identification and inadequate bee research program, are major concerns for beekeeping in Nepal. Though attempts have been made to address few issues such as pest and disease management, behavioral study of wild honey bees, pollination and floral diversity, but most of the problems are unattended because research on beekeeping is scattered and not well organized. Ample opportunities are available to promote apiculture for pollination and hive product. This paper reviews on honeybee diversity, honey production, problems in apiculture, and areas for future study in Nepal.

Complete mitochondrial genome of the Himalayan honey bee, Apis laboriosa

The complete mitochondrial genome of Himalayan bee Apis laboriosa, from Mizoram, India, has been sequenced using Illumina NextSeq500 platform and analysed. The mitogenome was assembled and found to be 15 266 bp in length and the gene arrangement is similar to other honey bee species. The A. laboriosa mitogenome comprises of 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs and an A + T-rich region of 346 bp. Based on the concatenated PCGs, in the phylogenetic tree, A. laboriosa is placed as a sister group along with the cavity nesting honey bees. The present study reports the first complete mitochondrial genome sequence of A. laboriosa, which will enhance our knowledge on Apinae mitogenomes and phylogeny.

Biomedical Activity and Related Volatile Compounds of Thai Honeys from 3 Different Honeybee Species.

This study investigated the effect of 3 factors (floral source, honeybee species, and postcollection processing) that influence the antibacterial activity, free radical reduction, and other biochemical compositions of different honey types typical of Thailand. Honey samples from 3 honeybee species (Apis mellifera, Apis cerana, and Apis dorsata) were obtained from 9 floral sources (longan, wild flower, lychee, coffee, sunflower, sesame, bitter bush, para-rubber, and manuka as a control) in different regions of Thailand. These samples were evaluated for both their total and nonperoxide antibacterial activity against 10 human pathogens by agar incorporation technique. Honey samples were further analyzed to evaluate the capacity for free radical-scavenging activity, total phenolic content, and the total flavonoid contents by the 2,2-diphenyl-1-picrylhydrazyl assay, Folin-Ciocalteu method, and aluminum chloride colorimetric assay, respectively. Furthermore, the volatile organic compounds (VOCs) of Thai honey samples were investigated by headspace solid-phase microextraction and gas chromatography-mass spectrometry analysis. Findings of this study suggest a strong correlation between floral origin and honeybee species on one hand, and differences in %Brix, total acidity, protein content, antimicrobial activities, free radical reduction, phenolic, and flavonoid contents on the other hand. Moreover, VOCs of wild and coffee honey types were remarkably different, depending on the floral source. Both honeys contained characteristics of VOCs, some of which are involved in antibacterial and antioxidant activities. Different origins and processing (floral source, honeybee species, and postcollection processing) of Thai honeys result in different antibacterial activities, physico-chemical properties, and aroma. Based on these findings, consumers of honey could select the type of honey based on their needs and preferred aroma.

Host Specificity in the Honeybee Parasitic Mite, Varroa spp. in Apis mellifera and Apis cerana.

The ectoparasitic mite Varroa destructor is a major global threat to the Western honeybee Apis mellifera. This mite was originally a parasite of A. cerana in Asia but managed to spill over into colonies of A. mellifera which had been introduced to this continent for honey production. To date, only two almost clonal types of V. destructor from Korea and Japan have been detected in A. mellifera colonies. However, since both A. mellifera and A. cerana colonies are kept in close proximity throughout Asia, not only new spill overs but also spill backs of highly virulent types may be possible, with unpredictable consequences for both honeybee species. We studied the dispersal and hybridisation potential of Varroa from sympatric colonies of the two hosts in Northern Vietnam and the Philippines using mitochondrial and microsatellite DNA markers. We found a very distinct mtDNA haplotype equally invading both A. mellifera and A. cerana in the Philippines. In contrast, we observed a complete reproductive isolation of various Vietnamese Varroa populations in A. mellifera and A. cerana colonies even if kept in the same apiaries. In light of this variance in host specificity, the adaptation of the mite to its hosts seems to have generated much more genetic diversity than previously recognised and the Varroa species complex may include substantial cryptic speciation.

Field populations of native Indian honey bees from pesticide intensive agricultural landscape show signs of impaired olfaction.

Little information is available regarding the adverse effects of pesticides on natural honey bee populations. This study highlights the detrimental effects of pesticides on honey bee olfaction through behavioural studies, scanning electron microscopic imaging of antennal sensillae and confocal microscopic studies of honey bee brains for calcium ions on Apis cerana, a native Indian honey bee species. There was a significant decrease in proboscis extension response and biologically active free calcium ions and adverse changes in antennal sensillae in pesticide exposed field honey bee populations compared to morphometrically similar honey bees sampled from low/no pesticide sites. Controlled laboratory experiments corroborated these findings. This study reports for the first time the changes in antennal sensillae, expression of Calpain 1(an important calcium binding protein) and resting state free calcium in brains of honey bees exposed to pesticide stress.

Similar but not the same: insights into the evolutionary history of paralogous sex-determining genes of the dwarf honey bee Apis florea.

Studying the fate of duplicated genes provides informative insight into the evolutionary plasticity of biological pathways to which they belong. In the paralogous sex-determining genes complementary sex determiner (csd) and feminizer (fem) of honey bee species (genus Apis), only heterozygous csd initiates female development. Here, the full-length coding sequences of the genes csd and fem of the phylogenetically basal dwarf honey bee Apis florea are characterized. Compared with other Apis species, remarkable evolutionary changes in the formation and localization of a protein-interacting (coiled-coil) motif and in the amino acids coding for the csd characteristic hypervariable region (HVR) are observed. Furthermore, functionally different csd alleles were isolated as genomic fragments from a random population sample. In the predicted potential specifying domain (PSD), a high ratio of πN/πS=1.6 indicated positive selection, whereas signs of balancing selection, commonly found in other Apis species, are missing. Low nucleotide diversity on synonymous and genome-wide, non-coding sites as well as site frequency analyses indicated a strong impact of genetic drift in A. florea, likely linked to its biology. Along the evolutionary trajectory of ~30 million years of csd evolution, episodic diversifying selection seems to have acted differently among distinct Apis branches. Consistently low amino-acid differences within the PSD among pairs of functional heterozygous csd alleles indicate that the HVR is the most important region for determining allele specificity. We propose that in the early history of the lineage-specific fem duplication giving rise to csd in Apis, A. florea csd stands as a remarkable example for the plasticity of initial sex-determining signals.

Honey Bees and Coffee

In Southeast Asia, the traditional “hive” bee has been the cavity nesting bee Apis cerana F., often referred to as the eastern or Asiatic honey bee. Management of this indigenous honey bee species ...

A neonicotinoid impairs olfactory learning in Asian honey bees (Apis cerana) exposed as larvae or as adults.

Xenobiotics such as the neonicotinoid pesticide, imidacloprid, are used globally, but their effects on native bee species are poorly understood. We studied the effects of sublethal doses of imidacloprid on olfactory learning in the native honey bee species, Apis cerana, an important pollinator of agricultural and native plants throughout Asia. We provide the first evidence that imidacloprid can impair learning in A. cerana workers exposed as adults or as larvae. Adults that ingested a single imidacloprid dose as low as 0.1 ng/bee had significantly reduced olfactory learning acquisition, which was 1.6-fold higher in control bees. Longer-term learning (1-17 h after the last learning trial) was also impaired. Bees exposed as larvae to a total dose of 0.24 ng/bee did not have reduced survival to adulthood. However, these larval-treated bees had significantly impaired olfactory learning when tested as adults: control bees exhibited up to 4.8-fold better short-term learning acquisition, though longer-term learning was not affected. Thus, sublethal cognitive deficits elicited by neonicotinoids on a broad range of native bee species deserve further study.

Varroa destructor changes its cuticular hydrocarbons to mimic new hosts.

Varroa destructor (Vd) is a honeybee ectoparasite. Its original host is the Asian honeybee, Apis cerana, but it has also become a severe, global threat to the European honeybee, Apis mellifera. Previous studies have shown that Varroa can mimic a host's cuticular hydrocarbons (HC), enabling the parasite to escape the hygienic behaviour of the host honeybees. By transferring mites between the two honeybee species, we further demonstrate that Vd is able to mimic the cuticular HC of a novel host species when artificially transferred to this new host. Mites originally from A. cerana are more efficient than mites from A. mellifera in mimicking HC of both A. cerana and A. mellifera. This remarkable adaptability may explain their relatively recent host-shift from A. cerana to A. mellifera.

Infectivity of Nosema ceranae isolates from different hosts and immune response in honey bees Apis mellifera and Apis cerana

The microsporidium, Nosema ceranae, was first discovered in Apis cerana. Currently, N. ceranae is a highly prevalent parasite in A. mellifera colonies worldwide. The pathology of N. ceranae and how bees defend themselves from this pathogen have been reported. Here, we investigated the infectivity of two N. ceranae isolates from different honey bee species, A. mellifera and A. cerana. Our results showed that the N. ceranae isolate from A. mellifera had a significantly higher infectivity than another isolate from A. cerana in all experimental cages of A. mellifera and A. cerana. Moreover, when comparing the infectivity of each N. ceranae isolate between the original and new hosts, it seems that no significant difference was obtained. The immunity-related enzymes in honey bees following N. ceranae inoculation were also analyzed at day six after spore feeding. Phenol oxidase (PO) transcript levels were up-regulated in A. cerana when inoculated by both N. ceranae isolates, but were not significantly different. However, the transcript level for PO in one experimental cage of A. mellifera was significantly down-regulated when inoculated with N. ceranae. Significant glucose dehydrogenase suppression occurred in only one cage of each honey bee species.

Honey Bees (Apis mellifera L.) and Pollination Issues: Current status, impacts and potential drivers of decline

European honey bees (Apis mellifera L.) are important pollinators of many fruits, nuts, vegetables and field crops. Honey bees also pollinate different wild flowering plants and help to maintain the ecosystems. Currently, these pollinators are facing a number of threats including habitat destruction, pesticides, mites, parasites and loss of genetic diversity. Because of the decline in their number, there is a great loss of ecological services which impacts the world’s economy. This review of honey bee and pollination issues highlights the need of protection and conservation of these important pollinators. Research is required to quantify the synergistic effects of potential drivers for current colony loss and to identify the ecotypes and native species of honey bees which are more resistant to pests, pathogens and pesticides.

Capsid Gene Divergence of Black Queen Cell Virus Isolates in Thailand and Japan Honey Bee Species

Black queen cell virus (BQCV) has been found in honey bees worldwide. By using the reverse transcription polymerase chain reaction (RT-PCR) technique, BQCV was detected in a non-native species, Apis mellifera L., collected in both Thailand and Japan, and three other honey bee species (Apis cerana indica F., Apis dorsata F., and Apis florae F.) native to Thailand and Apis cerana japonica F. native to Japan. Based on the capsid coding region, the phylogenetic analysis showed that the BQCV strains found in A. cerana indica and A. cerana japonica were similar within the group and closer to BQCV in Asia. It is interesting to note that the genetic variation of the BQCV isolates was more associated with geographic origin than the host bee species from which the isolates were obtained.

Relationship Between Honeybee Population and Honey Production in Korea : A Historical Trend Analysis

The honey bee provides various ecosystem service as well as direct income source of beekeeping industry. The primary product from beekeeping is the honey which is defined as “the natural sweet substance produced by honey bees from the nectar of plants, which the bees collect, transform by combining with specific substances of their own, deposit, dehydrate, store and leave in the honey comb to ripen and mature” In Korea, two species of honey bees are kept by beekeepers; Apis cerana and A. mellifera. There were four historical patterns of bee population found; phase I, A. cerana dominated but total hive numbers below 200,000 until 1950s, phase II, both species low below 500,000 until 1977, phase III, both species increasing with A. mellifera dominant until saturation of two million hives near 2005, and phase IV, A. mellifera dominating but A. cerana declining in 2010s. Patterns of national honey production were reflected by the hive population reaching 28,000 tons in 2009. Honey production per hive was 4kg in phase I, and 12.4kg during phase II-IV. If the numbers of A. mellifera colonies were considered, the productivity was 15kg per hive. Residual variation was higher in the recent years implying some other factors such as honey plant biology, pest and disease pressure could influence the honey yield which can be further studied.

A depauperate immune repertoire precedes evolution of sociality in bees.

BackgroundSociality has many rewards, but can also be dangerous, as high population density and low genetic diversity, common in social insects, is ideal for parasite transmission. Despite this risk, honeybees and other sequenced social insects have far fewer canonical immune genes relative to solitary insects. Social protection from infection, including behavioral responses, may explain this depauperate immune repertoire. Here, based on full genome sequences, we describe the immune repertoire of two ecologically and commercially important bumblebee species that diverged approximately 18 million years ago, the North American Bombus impatiens and European Bombus terrestris.ResultsWe find that the immune systems of these bumblebees, two species of honeybee, and a solitary leafcutting bee, are strikingly similar. Transcriptional assays confirm the expression of many of these genes in an immunological context and more strongly in young queens than males, affirming Bateman’s principle of greater investment in female immunity. We find evidence of positive selection in genes encoding antiviral responses, components of the Toll and JAK/STAT pathways, and serine protease inhibitors in both social and solitary bees. Finally, we detect many genes across pathways that differ in selection between bumblebees and honeybees, or between the social and solitary clades.ConclusionsThe similarity in immune complement across a gradient of sociality suggests that a reduced immune repertoire predates the evolution of sociality in bees. The differences in selection on immune genes likely reflect divergent pressures exerted by parasites across social contexts.Electronic supplementary materialThe online version of this article (doi:10.1186/s13059-015-0628-y) contains supplementary material, which is available to authorized users.

Variation in honey bee gut microbial diversity affected by ontogenetic stage, age and geographic location.

Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting.Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees.Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage.The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may be undergoing dynamic succession.

Complete genome of Chinese sacbrood virus from Apis cerana and analysis of the 3C-like cysteine protease.

The complete genome sequence of Chinese sacbrood virus (CSBV), isolated from diseased larvae of Apis cerana in Fujian province, China was analyzed. The viral genome consisted of 8,800 nucleotides, encoding 2,848 amino acids. A phylogenetic tree analysis showed the sacbrood virus (SBV) segregated into three distinct groups. The isolates originated from A. c. indica and were the first distinct evolutionary group. The AcSBV-SBM2 isolate, from A. c. cerana, belonged to the second distinct group. The remaining SBV isolates formed the third group. The phylogenetic relationships of SBV isolates suggest that they are derived from similar honeybee species or geographic origins. The 3C-like cysteine protease protein plays an important role in viral replication. The 3C-like cysteine protease protein of CSBV-FZ was predicted to contain a transmembrane domain. The subcellular localization of 3C-like cysteine protease was distributed as discrete punctate inclusions and co-localized with VP1 of CSBV. These results suggest that the non-structural protein 3C-like cysteine protease might be involved in viral replication. Insect cell cultures can further advance our understanding of picorna-like virus replication.

Uncovering the novel characteristics of Asian honey bee, Apis cerana, by whole genome sequencing.

BackgroundThe honey bee is an important model system for increasing understanding of molecular and neural mechanisms underlying social behaviors relevant to the agricultural industry and basic science. The western honey bee, Apis mellifera, has served as a model species, and its genome sequence has been published. In contrast, the genome of the Asian honey bee, Apis cerana, has not yet been sequenced. A. cerana has been raised in Asian countries for thousands of years and has brought considerable economic benefits to the apicultural industry. A cerana has divergent biological traits compared to A. mellifera and it has played a key role in maintaining biodiversity in eastern and southern Asia. Here we report the first whole genome sequence of A. cerana.ResultsUsing de novo assembly methods, we produced a 238 Mbp draft of the A. cerana genome and generated 10,651 genes. A.cerana-specific genes were analyzed to better understand the novel characteristics of this honey bee species. Seventy-two percent of the A. cerana-specific genes had more than one GO term, and 1,696 enzymes were categorized into 125 pathways. Genes involved in chemoreception and immunity were carefully identified and compared to those from other sequenced insect models. These included 10 gustatory receptors, 119 odorant receptors, 10 ionotropic receptors, and 160 immune-related genes.ConclusionsThis first report of the whole genome sequence of A. cerana provides resources for comparative sociogenomics, especially in the field of social insect communication. These important tools will contribute to a better understanding of the complex behaviors and natural biology of the Asian honey bee and to anticipate its future evolutionary trajectory.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-16-1) contains supplementary material, which is available to authorized users.

Molphological Analysis and Determination of Interference Competition between Two Honeybee Mites: Varroa destructor and Tropilaelaps clareae (Acari: Varroidae and Laelapidae)

The ectoparasitic honey bee mites was originally confined to the Asian honey bee (Apis cerana etc.). Mites attach to adults and developing brood, where they feed on the hemolymph. If left untreated, mites can deform bees and eventually kill the colony. Varroa destructor and Tropilaelaps clareae have plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We counted number of mites (V. destructor and T. clareae) from 20 colonies. V. destructor and T. clareae has very similar behavior in honeybee colony. When behaviorally close, two competing species may populational interfere, and thereby affect their population dynamics. We tested for populational interference (PI) between two populational competing honeybee mites, V. destructor and T. clareae, by investigating their population dynamics when they competed on the same colony. Population of V. destructors are increased during August, whereas population of T. clareaes are decreased. The effects of interspecific competition on the population growth of mites (focus in the colony) are summarized in data. The presence of T. clareae on with V. destructor led to reduce in the change of T. clareae population size at August compared with other season, indicating that some form of interspecific competition occurred between the two species.

Preliminary observations on possible pathogen spill-over from Apis mellifera to Apis cerana

Populations of Apis mellifera and Apis cerana in China and Vietnam were surveyed in order to study possible pathogen spill-over from European to Asian honeybees. This is the first survey of the prevalence of honeybee pathogens in apiaries in Vietnam, including pathogen prevalence in wild A. cerana colonies never in contact with A. mellifera. The bee samples were assayed for eight honeybee viruses: deformed wing virus (DWV); black queen cell virus (BQCV); sac brood virus (SBV); acute bee paralysis virus (ABPV); Kashmir bee virus (KBV); Israeli acute paralysis virus (IAPV); chronic bee paralysis virus (CBPV); and slow bee paralysis virus (SBPV), for two gut parasites (Nosema ssp.) and for the causative agent for European foulbrood (Melissococcus plutonius). The Vietnamese samples were assayed for Acarapis woodi infestation. No clear evidence of unique inter-specific transmission of virus infections between the two honeybee species was found. However, in wild A. cerana colonies, the only virus infection detected was DWV. With findings of IAPV infections in Chinese samples of A. cerana colonies in contact with A. mellifera, inter-specific transmission of IAPV cannot be ruled out. BQCV was the most prevalent virus in managed colonies irrespective of bee species. We did not detect the causative agent of European foulbrood, M. plutonius in wild or isolated colonies of A. cerana in Vietnam or China; however, low incidence of this pathogen was found in the Asian host species when in contact with its European sister species. No evidence for the presence of A. woodi was found in the Vietnamese samples.