Most of Venezuela's agriculture occurs in the dry tropical forest life zone; this region covers 38% of the country and accounts for about 85% of the national honey production. When harvesting honey many Venezuelan beekeepers remove Africanized bees from honey supers by smoking the supers with large amounts of smoke, then by brushing or shaking out any remaining bees. Beekeepers in Venezuela, like many beekeepers around the world, seldom agree on beekeeping methods. Many Venezuelan beekeepers are trying hybrids from different strains in an attempt to find less defensive and better honey-producing bees. Hybrids produced from the Carniolan subspecies are popular among several of the beekeepers. Most crops in Venezuela prior to Africanization were pollinated by native bees, primarily stingless bees. Honey in Venezuela is used primarily for medicinal purposes and for the baking and candy industries. Most of the honey produced by the commercial beekeepers is sold at wholesale prices to national supermarkets.

Acarapis dorsalis and Acarapis externus are parasites of adult honey bees in the United States since the 1930s. Here, we present historical and current data on their prevalence and abundance. In the late 1980s to early 2000, these two Acarapis species were frequently detected with A. externus being found at higher levels than A. dorsalis. The abundance of A. externus over A. dorsalis may be due to the lack of host age preference by A. externus as their prevalence and intensity remained high on bees up to 35 days old. In contrast, infestation rate and mite load of A. dorsalis decreased as bees become older. By examining 16,515 worker bees from 2007 to 2019, A. dorsalis was detected yearly while A. externus infestation was sporadic. The higher frequency of detecting A. dorsalis over A. externus may be due to their differences in colonization ability. A. dorsalis was faster in establishing their population in mite-free colonies than A. externus and was also successful in invading A. externus-infested colonies. The introduction of 50 A. dorsalis in mite-free colonies was sufficient to found a population while 500 A. externus may be too small to establish a population. Variation in responses to parasitic mites by different honey bee stocks also influenced Acarapis population. A. dorsalis was most prevalent in the Hastings stock while the levels of A. externus were higher on the ARS-Y-C-1, Hastings x ARS-Y-C-1 hybrid and Louisiana stocks. The Russian honey bees also had higher levels of A. dorsalis than the Italian honey bees. However, both stocks’ responses to A. externus were inconsistent. Nonetheless, both ARS-Y-C-1 and Russian honey bees are known to be resistant to another Acarapis species, A. woodi, which is known to be a more serious parasite of honey bees than these two external Acarapis. The potential role of external Acarapis in virus transmission especially in Varroa-infested colonies needs to be studied.

We examine the origin of honey bee (Apis mellifera) populations in Kangaroo Island (Australia), Norfolk Island (Australia) and the Kingdom of Tonga using a highly polymorphic mitochondrial DNA region and a panel of 37 single nucleotide polymorphisms that assigns ancestry to three evolutionary lineages: Eastern Europe, Western Europe and Africa. We also examine inbreeding coefficients and genetic variation using microsatellites and mitochondrial sequencing. The honey bees of Kangaroo Island have a high proportion of Eastern European ancestry (90.2%), consistent with claims that they are of the subspecies A. m. ligustica. The honey bees of Norfolk Island also had a majority of ancestry from Eastern Europe (73.1%) with some contribution from Western Europe (21.2%). The honey bees of Tonga are mainly of Western European (70.3%) origin with some Eastern European ancestry (27.4%). Despite the suspected severe bottlenecks experienced by these island population, inbreeding coefficients were low.

The removal of Varroa destructor was assessed in Russian honey bee (RHB) colonies with known levels of Varroa Sensitive Hygienic (VSH) and brood removal activities. The expression of grooming behaviour using individual bees was also measured using three groups of RHB displaying different VSH levels: low hygiene (RHB-LH, < 35% VSH), medium hygiene (RHB-MH, 35–70%) and high hygiene (RHB-HH, > 70%). Italian colonies (5.43–71.62% VSH) served as control. Our results demonstrated, for the first time, significant relationships between two hygienic responses (VSH activity measured as percent change in infestation and the actual brood removal of Varroa-infested donor comb) and two measurements of mite fall (trapped old mites/trapped mites or O/T and trapped young mites/trapped mites or Y/T). However, these relationships were only observed in RHB colonies. In addition, the RHB colonies that displayed the highest levels of hygiene (RHB-HH) also groomed longer in response to the presence of a V. destructor mite based on individual bee assays. The positive regressions between the two hygienic measurements and O/T and their negative regressions with Y/T suggest that the removal of infested brood prevented successful mite reproduction, ultimately suppressing V. destructor infestations in the RHB colonies. In addition, it is demonstrated that RHB resistance to V. destructor rests on both an increased hygienic response and the removal of phoretic mites, released by hygienic behaviour, through grooming. Both resistance traits are reflected in the O/T and Y/T ratios found in trapped mites from RHB colonies. None of the measurements involving mite injuries were associated with any measurements of hygiene and colony infestations.

Adulticides applied against mosquitoes can reduce vector populations during times of high arbovirus transmission. However, impacts of these insecticides on pollinators and other non-target organisms are of concern to mosquito control professionals, beekeepers and others. We evaluated mortality of Culex quinquefasciatus and Apis mellifera when caged insects were exposed to low and high label rates of four common adulticides (Aqua-Pursuit™ [permethrin], Duet® [prallethrin + sumithrin], Fyfanon® [malathion] and Scourge® [resmethrin]) at six distances up to 91.4 m from a truck-mounted ultra-low-volume sprayer. Honey bee mortality was both absolutely low (61 m had limited impacts on honey bee mortality while providing effective mosquito control.

We examine whether a panel of 37 single nucleotide polymorphisms (SNPs) has the same power as a more expensive panel of 95 SNPs to assign ancestry of honeybees (Apis mellifera) to three ancestral lineages. We selected SNPs using allele frequencies, such that poorly performing SNPs were excluded. We find that ancestry assignment is comparable between the two panels. Importation of bee semen from countries where Africanized bees are present into countries where Africanized bees are absent would be facilitated if small proportions of semen derived from Africanized drones can be reliably detected. We used the abbreviated panel to determine if semen from a single Africanized drone could be detected when mixed with the semen of 10, 20 or 40 non-Africanized drones. We found that the use of the 37 SNP test on a mixed sample would fail to detect the contribution of a single Africanized male. It is therefore important that the cadavers of the males contributing semen are individually tested.

With increased globalisation and homogenisation, the maintenance of genetic integrity in local populations of agriculturally important species is of increasing concern. The western honeybee ( Apis mellifera ) provides an interesting perspective as it is both managed and wild, with a large native range and much larger introduced range. We employed a newly created 95 single nucleotide polymorphism (SNP) test to characterise the genetic ancestry of the Australian commercial and feral honeybee populations. We found that most individuals were hybrids of mainly Western and Eastern European ancestry. Introductions of bees from North Africa are known from the historical record, and we show here the presence of alleles of African ancestry in some Australian bees, at levels comparable to those seen in the commercial populations of European-derived bees in North America.

Apis mellifera syriaca is the native honeybee subspecies of Jordan and much of the Levant region. It expresses behavioral adaptations to a regional climate with very high temperatures, nectar dearth in summer, attacks of the Oriental wasp and is resistant to Varroa mites. The A. m. syriaca control reference sample (CRS) in this study was originally collected and stored since 2001 from “Wadi Ben Hammad”, a remote valley in the southern region of Jordan. Morphometric and mitochondrial DNA markers of these honeybees had shown highest similarity to reference A. m. syriaca samples collected in 1952 by Brother Adam of samples collected from the Middle East. Samples 1–5 were collected from the National Center for Agricultural Research and Extension breeding apiary which was established for the conservation of A. m. syriaca. Our objective was to determine the success of an A. m. syriaca honey bee conservation program using genomic information from an array-based comparative genomic hybridization platform to evaluate genetic similarities to a historic reference collection (CRS). Our results had shown insignificant genomic differences between the current population in the conservation program and the CRS indicated that program is successfully conserving A. m. syriaca. Functional genomic variations were identified which are useful for conservation monitoring and may be useful for breeding programs designed to improve locally adapted strains of A. m. syriaca.

The negative impact of Deformed wing virus (DWV) on European honey bees Apis mellifera is magnified by Varroa destructor parasitism. This study compared the responses of two Varroa-resistant honey bee stocks, pure Russian honey bees (RHB) and out-crossed Varroa Sensitive Hygienic bees, Pol-line (POL) to DWV infection to that of Varroa- susceptible stock, Italian honey bees (IHB). Two-day-old larvae were fed with DWV lysate in different concentrations: undiluted DWV lysate (D1), D1:100, and D1:1000. The unfed larvae served as negative control. Combs containing test larvae were exposed to a common environment during their development using host colonies. Our results showed that only POL displayed variation in DWV levels when fed different DWV concentrations. POL fed highest concentration of DWV inoculum had the highest increase in DWV level than those fed low concentrations and unfed POL. This high increase in DWV level probably contributed to the decrease in the survival and median longevity (LT50) of D1-fed POL. Weights of newly eclosed D1-fed POL were similar to those of the two controls and DWV-fed bees. However, within IHB, D1-fed bees showed significant reductions in weight, days of survival and LT50. Regardless of the concentrations of DWV inoculum, the DWV levels were similarly low within RHB; adult bees had similar weights. Overall, larvae fed D1 had the highest rate of wing deformation. POL and RHB had numerically lower proportions of bees with deformed wings. This study suggests that RHB showed some degree of resistant to DWV as shown by no reduction on weight and numerically lower proportion of wing deformity when compared with the other bee stocks.

Two important traits that contribute to honey bee (Apis mellifera) colony survival are resistance to varroa and longevity of worker bees. We investigated the relationship between a panel of single nucleotide polymorphism markers and three phenotypic measurements of colonies: (a) percentage of mites in brood (MIB); (b) proportion of fallen injured mites; and (c) longevity of workers. We used single marker analysis to identify genetic intervals that may confer resistance and increased lifespan. One gene related to memory and learning, Ddc was identified for MIB, as was acj6, which functions for olfactory perception. These genes may contribute to elevated levels of mite detection and removal. Three genes were identified with high relevance for mite injury. CYP315A1 and Ptp69D function in motor neuron axon guidance in response to chemical stimuli. RabGAP11 is also involved in sensory function, specifically sensory organ development. Evidence for the longevity quantitative trait locus was also strong and one gene (Orct) is related to improved lifespan in both humans and Drosophila. Together, these genes provide possible avenues to be pursued for further development for eventual marker-assisted selection.

The hygienic removal of Apis mellifera brood infested with Varroa destructor disrupts the reproduction of the infesting mites, and exposes the foundress mites to potential removal from the colony by grooming. Using brood deliberately infested with marked mites, we investigated the association between the removal of mite-infested brood and the removal of exposed foundress mites in Italian (IHB) and Russian honey bee (RHB) colonies. Our results showed that RHB colonies removed more mite-infested brood in significantly less time (average=87.92.0% for 2.6 +/- 0.1days) than IHB colonies (average=61.9 +/- 7.3% for 3.2 +/- 0.1days or 19.3% per day). For the inoculated brood that was not removed, RHB colonies had lower proportions of brood cells containing: (a) live marked mites regardless of reproductive status (RHB=4.4 +/- 1.3%; IHB=17.7 +/- 5.9%); (b) dead marked mites (RHB=1.1 +/- 0.5%; IHB=7.1 +/- 2.2%); (c) lost introduced marked mites (RHB=6.6 +/- 1.6%; IHB=13.3 +/- 2.8%); and (d) reproductive marked mites (RHB=8.3 +/- 6.3%; IHB=23.8 +/- 6.9%) than IHB colonies did. These observations suggest that RHB colonies indiscriminately remove mite-infested brood regardless of mite status. Regarding trapped mites (i.e., those found below a modified queen excluder), the number of mite-infested brood cells removed positively correlated with the number of mites that were trapped in both honey bee stocks. The majority of the trapped mites fell during the first three days post mite inoculation, which coincided with the highest rates of brood removal. The highest proportions of trapped gravid foundress mites were also recorded during this time, when host bees were early in their development. The comparatively strong and rapid hygienic response of RHB to mite-infested brood and the associated removal of infesting foundresses are probably parts of a suite of factors responsible for suppressing V. destructor populations in RHB colonies.

The effects of natural diet (brood, pollen, honey, and their various combinations), mating duration (1 day versus 2 days), female (F) to male (M) ratio (1F/1M, 2F/1M, and 1F/2M), and temperature (34 versus 27–29 °C) on ovary activation, mating success, and fecundity of small hive beetles (SHBs) were studied. Our results indicated that regardless of mating duration, (1) a diet of brood, pollen, and honey presented together supported the highest fecundity; (2) intake of protein-rich diets encouraged ovary activation and egg-laying; and (3) diet of honey alone did not encourage ovary activation, mating success, and egg-laying at room temperature. Regardless of the number of males available for mating, egg-laying varied through time. Overall, females that were presented with two males for a 5-day mating period had higher fecundity than females provided with one male or three male partners. High temperature accelerated ovary activation and egg-laying regardless of female to male ratio during a 15-h mating period. Knowledge of these factors that influence fecundity helps elucidate why SHBs are very successful pests of honey bees.

Canadian honey bees, like all honey bees in the New World, originated from centuries of importation of predominately European subspecies, but their precise genetic ancestry has not been investigated. We used a citizen science approach that engaged a diverse group of beekeepers to undertake the largest population genetic study of Canadian honey bees. We used the dataset to characterize the ancestry of Canadian honey bee populations, test if Northern Canadian colonies have a greater proportion of ancestry from subspecies native to Northern Europe, and determine the effectiveness of using single nucleotide polymorphism (SNPs) to distinguish between Canadian bees and the aggressive and invasive Africanized honey bee found from South America to the Southern United States. We genotyped 855 worker honey bees at 91 ancestrally informative SNPs and found very low levels of genetic differentiation within Canada at these SNPs and small but significant differences in ancestry between provinces. Honey bee populations in Northern and Western Canada were more closely related to subspecies from Southern and Mediterranean Europe. We attributed this pattern to differences in importation practices within Canada. Finally, we were able to accurately discriminate between Africanized bees and Canadian bees using the ancestrally informative SNPs, supporting the use of SNPs for accurately detecting Africanized honey bees and providing valuable insights into the genetic structure of Canadian bees, all while engaging beekeepers in the scientific process.

To combat an increasing abundance of sucking insect pests, >40 pesticides are currently recommended and frequently used as foliar sprays on row crops, especially cotton. Foraging honey bees may be killed when they are directly exposed to foliar sprays, or they may take contaminated pollen back to hives that maybe toxic to other adult bees and larvae. To assess acute toxicity against the honey bee, we used a modified spray tower to simulate field spray conditions to include direct whole-body exposure, inhalation, and continuing tarsal contact and oral licking after a field spray. A total of 42 formulated pesticides, including one herbicide and one fungicide, were assayed for acute spray toxicity to 4-6-d-old workers. Results showed significantly variable toxicities among pesticides, with LC50s ranging from 25 to thousands of mg/liter. Further risk assessment using the field application concentration to LC1 or LC99 ratios revealed the risk potential of the 42 pesticides. Three pesticides killed less than 1% of the worker bees, including the herbicide, a miticide, and a neonicotinoid. Twenty-six insecticides killed more than 99% of the bees, including commonly used organophosphates and neonicotinoids. The remainder of the 13 chemicals killed from 1-99% of the bees at field application rates. This study reveals a realistic acute toxicity of 42 commonly used foliar pesticides. The information is valuable for guiding insecticide selection to minimize direct killing of foraging honey bees, while maintaining effective control of field crop pests.

Asexual reproduction via thelytokous parthenogenesis is widespread in the Hymenoptera, but its genetic underpinnings have been described only twice. In the wasp Lysiphlebus fabarum and the Cape honey bee Apis mellifera capensis the origin of thelytoky have each been traced to a single recessive locus. In the Cape honey bee it has been argued that thelytoky (th) controls the thelytoky phenotype and that a deletion of 9 bp in the flanking intron downstream of exon 5 (tae) of the gemini gene switches parthenogenesis from arrhenotoky to thelytoky. To further explore the mode of inheritance of thelytoky, we generated reciprocal backcrosses between thelytokous A. m. capensis and the arrhenotokous A. m. scutellata. Ten genetic markers were used to identify 108 thelytokously produced offspring and 225 arrhenotokously produced offspring from 14 colonies. Patterns of appearance of thelytokous parthenogenesis were inconsistent with a single locus, either th or tae, controlling thelytoky. We further show that the 9 bp deletion is present in the arrhenotokous A. m. scutellata population in South Africa, in A. m. intermissa in Morocco and in Africanized bees from Brazil and Texas, USA, where thelytoky has not been reported. Thus the 9 bp deletion cannot be the cause of thelytoky. Further, we found two novel tae alleles. One contains the previously described 9 bp deletion and an additional deletion of 7 bp nearby. The second carries a single base insertion with respect to the wild type. Our data are consistent with the putative th locus increasing reproductive capacity.

The honeybee, Apis mellifera, is the world's most important pollinator and is ubiquitous in most agricultural ecosystems. Four major evolutionary lineages and at least 24 subspecies are recognized. Commercial populations are mainly derived from subspecies originating in Europe (75–95%). The Africanized honeybee is a New World hybrid of A. m. scutellata from Africa and European subspecies, with the African component making up 50–90% of the genome. Africanized honeybees are considered undesirable for bee‐keeping in most countries, due to their extreme defensiveness and poor honey production. The international trade in honeybees is restricted, due in part to bans on the importation of queens (and semen) from countries where Africanized honeybees are extant. Some desirable strains from the United States of America that have been bred for traits such as resistance to the mite Varroa destructor are unfortunately excluded from export to countries such as Australia due to the presence of Africanized honeybees in the USA. This study shows that a panel of 95 single nucleotide polymorphisms, chosen to differentiate between the African, Eastern European and Western European lineages, can detect Africanized honeybees with a high degree of confidence via ancestry assignment. Our panel therefore offers a valuable tool to mitigate the risks of spreading Africanized honeybees across the globe and may enable the resumption of queen and bee semen imports from the Americas.

Tropilaelaps mites are the major health threat to Apis mellifera colonies in Asia because of their widespread occurrence, rapid population growth and potential ability to transfer bee viruses. Honey bee immune responses in the presence of feeding mites may occur in response to mite feeding, to the presence of viruses, or to both. In this study, the mRNA expression levels were measured for three antimicrobial peptide encoding genes (abaecin, apidaecin and hymenoptaecin) and a phagocytosis receptor gene (eater) in worker brood infested with different numbers of actively feeding T. mercedesae. Also, all samples were measured for the amount of acute bee paralysis virus (ABPV), black queen cell virus (BQCV), deformed wing virus (DWV), Kashmir bee virus (KBV) and sacbrood virus (SBV). Using an artificial mite inoculation protocol, the analysis showed that apidaecin was significantly down-regulated when tan-bodied pupae were infested with 1-2 mites and when capping of the cells of newly sealed larvae were opened and closed without mite inoculation (o/c) as compared to the control group (undisturbed brood, no mite inoculation). Reduced transcription levels of the eater gene were also recorded in the o/c group. However, an up-regulation of apidaecin and eater genes was observed in highly infested pupae when compared to o/c group. This occurrence is perhaps due to an adaptive response of the bees to higher mite infestations by up-regulating their immune expression. No significant expression differences were detected for abaecin and hymenoptaecin and the viruses ABPV, KBV and SBV were not detected. However, 86.7% of the pupae were infected with DWV, 83.3% were infected with BQCV and 73% were infected by both of these viruses. In addition, the Tropilaelaps-inoculated pupae showed higher levels and incidence of DWV compared to uninfested pupae. The presence of these two honey bee viruses was not related to the number of T. mercedesae infesting the pupae. Also, the presence of variable levels of DWV and low levels of BQCV did not provoke any expression differences for any of the targeted genes. Overall, this research indicates that feeding by Tropilaelaps mites produces an immune response, that the level of viruses did not produce a correlated immune response by the four genes tested and that Tropilaelaps may be a potential vector of DWV but not to a high degree. The data indicated that the major impact of Tropilaelaps infestation is caused by the mite itself.