Local honeybee (<Emphasis Type="Italic">Apis mellifera mellifera</Emphasis> L.) populations in the Urals

The COI-COII intergenic region of mitochondrial DNA (mtDNA) was studied in local honeybee (Apis mellifera mellifera) L. populations from the Middle and Southern Urals. Analysis of bee colonies in these regions revealed apiaries enriched in families descending from A. m. mellifera in the maternal lineage. These results confirm the suggestion of preservation of A. m. mellifera refuges in the Urals and provide grounds for work on the preservation of the gene pool of this bee variety, valuable for all Russia.     

Use of a PCR method for controlling pure-breeding of honeybees Apis mellifera mellifera L. in the southern Urals

A key problem of honeybee (Apis mellifera mellifera) breeding in the Southern Urals is its cross-breeding with the Caucasian honeybee Apis mellifera caucasica. Mitochondrial DNA (mtDNA) in these subspecies differ in the length of a fragment localized between genes CO-I and CO-II, which can be used as a marker. A pair of 20-mer primers for PCR was chosen by means of computer design in order to determine the fragment size in both of the subspecies. The amplified fragment was shown to have a length of 350 bp in A. m. caucasica and 600 bp in A. m. mellifera. The difference in length results from the different ratio between two main elements P and Q, which comprise a major part of this sequence in these subspecies: a copy of P element and two copies of Q element in A. m. mellifera, and a copy of Q element only in A. m. caucasica. This sharply defined distinction allows us to use PCR for differentiating the subspecies, estimating the heterogeneity in the colonies, and rejecting queens in the selection process because of the maternal inheritance of the studied character. The nucleotide sequence of the amplified mtDNA fragment of A. m. mellifera was determined.     

Intestinal enterobacteria of the hibernating Apis mellifera mellifera L. bees

Dynamics of enterobacteria of normal intestinal microflora was studied in Apis mellifera mellifera L. bees hibernating under snow in the Western Urals. The cell numbers (N) of the predominant species Klebsiella oxytoca increased from 10-10(6) CFU/bee in November 2004 to 10(4)-10(7) CFU/bee in March 2005; its frequency of occurrence (P) increased from 92 to 100%. Increase of Providencia rettgeri (11.2004: N up to 10(6), P 25%; 03.2005: N 10(2)-10(6), P 80%) was accompanied by the substitution of Morganella morganii (11.2004: N up to 10(6), P 25%) with Proteus vulgaris (03.2005: N up to 10(5), P 8%). By spring, Hafnia alvei and Citrobacter sp., which are pathogenic to bees, disappeared (11.2004: N up to 10(5), P 13 and 10%, respectively). Endophytic species Pantoea agglomerans, Leclecria sp., and other representatives of the "Enterobacter agglomerans" group were present in November and after the first emergence in spring (N up to 10(5); November: P 15%; April: P 23%). In April, the number of enterobacteria decreased to 10(5), and P. rettgeri became the predominant species (P 54%) instead of K. oxytoca (P 43%).     

Expression of heat shock proteins in adult honey bee (Apis mellifera L.) workers under hot-arid subtropical ecosystems

Heat stress elicits the expression of heat shock proteins (HSPs) in honey bee subspecies. These highly conserved proteins have significant role in protecting cells from thermal-induced stresses. Honey bees in subtropical regions face extremely dry and hot environment. The expression of HSPs in the nurses and foragers of indigenous (Apis mellifera jemenitica) and imported European (Apis mellifera ligustica and Apis mellifera carnica) honey bee subspecies after heat shock treatment were compared using SDS-PAGE. Hsp70 and Hsp82 were equally expressed in the nurses of all tested bee subspecies when exposed to 40 °C and 45 °C for 4 h. The forager bees exhibited differential expression of HSPs after heat stress. No HSPs was expressed in the foragers of A. m. jemenitica, and Hsp70 was expressed only in the foragers of A. m. ligustica and A. m. carnica at 40 °C. A prominent diversity in HSPs expression was also exhibited in the foragers at 45 °C with one HSP (Hsp70) in A. m. jemenitica, two HSPs (Hsp40 and Hsp70) in A. m. carnica, and three HSPs (Hsp40, Hsp60 and Hsp70) in A. m. ligustica. No HSPs was expressed in the control nurse and forager bees at any of the tested temperatures. These findings illustrated the differences in HSP expression among nurse and forager bees. It is obvious that the native foragers are more heat tolerant with least HSPs expression than exotic bee races. Further investigations will help to understand the potential role of HSPs in the adaptability, survival, and performance of bee subspecies in harsh climate of the subtropical regions.     

Analysis of peptides in the brain and corpora cardiaca-corpora allata of the honey bee, Apis mellifera using MALDI-TOF mass spectrometry

The neuropeptide profiles and diversity of the brain and retrocerebral organs (corpora cardiaca-corpora allata; CC-CA) of adult workers of the honey bee Apis mellifera carnica (dark European strain) were investigated using a combination of HPLC and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) with post-source decay (PSD) and collision-induced dissociation (CID) fragmentation. Using evidence from genomic sources, including BLAST searches of the honey bee genome, comparisons with other species and de novo sequencing by PSD and CID fragmentation, a total of 13 mass ions could be assigned to peptides predicted from the A. mellifera genomic database. Peptides positively identified were A. mellifera tachykinin-related peptides 3 and 4 (APMGFQGMRa; APMGFYGTRa) and leucomyosuppressin (pEDVDHVFLRFa). Peptides tentatively identified were A. mellifera tachykinin-related peptides 2 and 5 (ALMGFQGVRa; ARMGFHGMRa), A. mellifera allatostatins 2, 3 and 4 (GRDYSFGLa; RQYSFGLa; GRQPYSFGLa), A1-SIFamide (AYRKPPFNGSIFa), Q1-leucomyosuppressin (QDVDHVFLRFa) and A. mellifera pyrokinins PK 1, PK 2 and Q1-PK 2 (TSQDITSGMWFGPRLa; pEITQFTPRLa; QITQFTPRLa). Allatostatins, tachykinin-related peptides and A1-SIFamide were not detected in CC-CA extract, which appears to contain predominantly leucomyosuppressin, Q1-leucomyosuppressin, PK 1, PK 2, Q1-PK 2 and some unidentified masses. No ion signal was detected that would correspond to the hypertrehalosaemic peptide (=Manse-AKH), which has been isolated from the Italian race of the honey bee (A. mellifera ligustica), but not from A. mellifera carnica.     

Population structure and Mdh-1 locus variation in Apis mellifera ligustica

In a wide area of the Piedmont of Italy the apiaries of Apis mellifera ligustica Spin., (the Italian bee) show homogeneous allelic frequency distributions at the Mdh-1 locus, the only one known to be polymorphic in worker bees. This can be explained by considering that an apiary is not a closed genetic system and that among apiaries gene flow is sufficient to overcome the different forces of inbreeding and random genetic drift. Nevertheless there is some evidence for partial subdivision because the pooled samples show a weak Wahlund effect. Moreover, the M allele at the same locus can be used as a diagnostic marker to distinguish A. m. ligustica populations (M absent or at very low frequencies) from A. m. mellifera French populations (monomorphic for M). The two honey-bee varieties, almost entirely separated by the Alps, hybridize with each other in very limited alpine areas. Hybrid populations show intermediate M frequencies.     

Occurrence and prevalence of seven bee viruses in Apis mellifera and Apis cerana apiaries in China

Populations of Apis mellifera and Apis cerana in China were surveyed for seven bee viruses: acute bee paralysis virus (ABPV), black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Kashmir bee virus (KBV), sacbrood virus (SBV), and Isreal acute paralysis virus (IAPV). No KBV was detected from any samples of the two species. In A. mellifera, DWV was the most prevalent virus, but in A. cerana, SBV was the dominant. Simultaneous multiple infections of viruses were common in both species. This is the first report of detection of IAPV and CBPV in A. cerana.     

DNA RFLPs at a highly polymorphic locus distinguish European and African subspecies of the honey bee Apis mellifera L. and suggest geographical origins of New World honey bees

A highly polymorphic locus in the honey bee, Apis mellifera L., was detected with genomic probe pB178. Eighty-five alleles, consisting of Msp I and Dde I RFLPs, were found among the Old and New World bees tested. Forty-one Msp I and 43 Dde I restriction fragment patterns, or variants, were identified. Variants and alleles were discontinuously distributed in Old World European and African subspecies. Principal coordinate analysis of the genetic distances between the alleles resulted in the identification of three distinct groups corresponding to three groups of honey bee races with historically different geographical distributions: east European A. m. ligustica and A. m. caucasica ; west European A. m. mellifera ; and South African A. m. scutellata . The clustering of alleles into these groups is consistent with previous honey bee phylogeographic studies, employing other nuclear and mitochondrial DNA markers, which in part support the evolutionary history of the honey bee hypothesized by Ruttner based on morphometric and allozyme data. The majority of alleles in bees from the USA grouped with those found in east European bees, while other alleles grouped with alleles found in A. m. mellifera . While the majority of the alleles in neotropical bees grouped with or were identical to African alleles, other alleles grouped with alleles found in A. m. mellifera, A. m. ligustica , and A. m. caucasica . Clues to the ancestry of neotropical bees may be found in the identification of alleles that were identical or more similar to alleles found in South African and west European bees; evidence for west European ancestry has been suggested using other taxonomic characters that were not unique to west European bees. Both west European and African alleles were found in individual neotropical colonies, which may indicate that honey bee subspecies which evolved allopatrically have hybridized in the human-assisted extension of their original geographical ranges.     

西方蜜蜂和兰州熊蜂在设施桃园的访花偏好性比较

【目的】为了比较西方蜜蜂 Apis mellifera 和兰州熊蜂 Bombus lantschouensis 在设施桃园内对不同时期桃花的访花偏好性、以及这种偏好性与花粉活力和采集花粉花蜜之间的关系。【方法】记录2种蜂在温室桃园内访问早期花、中期花和晚期花的比例,测定桃花不同时期的花粉活力以及2种蜂携带的花粉活力,观察2种蜂采集花蜜和采集花粉的成功率,统计2种蜂访花过程中桃花所处的枝条数及植株数。【结果】桃花不同时期的花粉活力差异显著,早期花花药未开裂,花粉未释放,中期花花粉活力（58.3%）显著高于晚期花花粉活力（34.2%）（P<0.01）;西方蜜蜂更加偏好访问中期花,对中期花的访问率高达75.3%,显著高于兰州熊蜂对中期花的访问率（49.2%）（P<0.01）;西方蜜蜂携带的花粉活力（92.1%）显著高于兰州熊蜂携带的花粉活力（72.9%）,但是西方蜜蜂采集花粉和采集花蜜的成功率均低于兰州熊蜂（P<0.01）;在访问一定数量的桃花过程中,兰州熊蜂在设施桃园内访问的枝条数和植株数较多,分布范围较广（P<0.01）。【结论】和兰州熊蜂相比,西方蜜蜂对活力花粉的辨别能力更强,更加偏好访问花粉活力较高的花朵,这种偏好性导致其采集花粉花蜜的成功率降低。     

Influence of honey bee, Apis mellifera, hives and field size on foraging activity of native bee species in pumpkin fields

The purpose of this study was to identify bee species active in pumpkin fields in New York and to estimate their potential as pollinators by examining their foraging activity. In addition, we examined whether foraging activity was affected by either the addition of hives of the honey bee, Apis mellifera L., or by field size. Thirty-five pumpkin (Cucurbita spp.) fields ranging from 0.6 to 26.3 ha, 12 supplemented with A. mellifera hives and 23 not supplemented, were sampled during peak flowering over three successive weeks in 2008 and 2009. Flowers from 300 plants per field were visually sampled for bees on each sampling date. A. mellifera, Bombus impatiens Cresson, and Peponapis pruinosa (Say) accounted for 99% of all bee visits to flowers. A. mellifera and B. impatiens visited significantly more pistillate flowers than would be expected by chance, whereas P. pruinosa showed no preference for visiting pistillate flowers. There were significantly more A. mellifera visits per flower in fields supplemented with A. mellifera hives than in fields not supplemented, but there were significantly fewer P. pruinosa visits in supplemented fields. The number of B. impatiens visits was not affected by supplementation, but was affected by number of flowers per field. A. mellifera and P. pruinosa visits were not affected by field size, but B. impatiens visited fewer flowers as field size increased in fields that were not supplemented with A. mellifera hives. Declining A. mellifera populations may increase the relative importance of B. impatiens in pollinating pumpkins in New York.     

Nosema ceranae is a long-present and wide-spread microsporidian infection of the European honey bee (Apis mellifera) in the United States

Honey bee samples collected between 1995 and 2007 from 12 states were examined for the presence of Nosema infections. Our results showed that Nosema ceranae is a wide-spread infection of the European honey bee, Apis mellifera in the United States. The discovery of N. ceranae in bees collected a decade ago indicates that N. ceranae was transferred from its original host, Apis cerana to A. mellifera earlier than previously recognized. The spread of N. ceranae infection in A. mellifera warrants further epidemiological studies to identify conditions that resulted in such a widespread infection.     

Performance of Apis mellifera, Bombus impatiens, and Peponapis pruinosa (Hymenoptera: Apidae) as pollinators of pumpkin

Pollination services of pumpkin, Cucurbita pepo L., provided by the European honey bee, Apis mellifera L., were compared with two native bee species, the common eastern bumble bee, Bombus impatiens (Cresson), and Peponapis pruinosa Say, in New York from 2008 to 2010. Performance of each species was determined by comparing single-visit pollen deposition, percentage of visits that contacted the stigma, flower-handling time, fruit and seed set, and fruit weight per number of visits. Fruit yield from small fields (0.6 ha) supplemented with commercial B. impatiens colonies was compared with yield from those not supplemented. A. mellifera spent nearly 2 and 3 times longer foraging on each pistillate flower compared with B. impatiens and P. pruinosa, respectively. A. mellifera also visited pistillate flowers 10-20 times more frequently than B. impatiens and P. pruinosa, respectively. Yet, B. impatiens deposited 3 times more pollen grains per stigma and contacted stigmas significantly more often than either A. mellifera or P. pruinosa. Fruit set and weight from flowers visited four to eight times by B. impatiens were similar to those from open-pollinated flowers, whereas flowers pollinated by A. mellifera and P. pruinosa produced fewer fruit and smaller fruit compared with those from open-pollinated flowers. Fields supplemented with B. impatiens produced significantly more pumpkins per plant than nonsupplemented fields. B. impatiens was a better pollinator of pumpkin than P. pruinosa and should be considered as a promising alternative to A. mellifera for pollinating this crop.     

Honey bee guards, Apis mellifera, accept own subspecies non-nestmates more than other subspecies non-nestmates

Summary: Honey bee nest entrance guards accepted a significantly lower proportion of non-nestmates of a different subspecies (5 %) than non-nestmates of their own subspecies (18 %). This result was consistent for 5 of the 6 study colonies (the sixth rejected all non-nestmates), 3 each of Apis mellifera mellifera and A.m. ligustica, and for each subspecies of guards (A.m.m. 5 % v 17 %; A.m.l. 4 % v 20 %). These data indicate that there are consistent recognition cue differences across subspecies.     

Chill sensitivity of honey bee, Apis mellifera, embryos

Improved methods for preservation of honey bee, Apis mellifera L., germplasm would be very welcome to beekeeping industry queen breeders. The introduction of two parasites and the emergence of an antibiotic resistant disease have increased demands for resistant stock. Techniques for artificial insemination of queens are available, and semen has been cryopreserved with limited success. However, cryopreservation of embryos for rearing queens would mesh well with current practices and also provide drones (haploid males). Eggs at five ages between twenty-four hours and sixty-two hours were exposed to 0, -6.6, and/or -15 degrees C for various times, and successful hatch measured. Honey bee embryos show chill sensitivity as do other insect embryos, and the rate of chill injury increases dramatically with decrease in holding temperature. The 48 h embryos in both groups showed the greatest tolerance to chilling, although 44 h embryos were only slightly less so.     

Studies on the possible competition for pollen between the honey bee, Apis mellifera sudanensis, and the imported dwarf honey bee Apis florea (Hym., Apidae) in North-Khartoum (Sudan)

Abstract:   Based on identification of collected pollen, in the area of North Khartoum, 21 plant genera (ca. 21 spp.) proved to be the main pollen sources for the honey bee Apis mellifera sudanensis . The imported dwarf honey bee Apis florea exploited 11 of these. The main pollen flow in the study area occurred between early December and late March. This is reflected by the amount of pollen collected by colonies of A. mellifera sudanensis . In spite of observations conducted soon after the introduction of A. florea , which gave hints of competition between the two bee species, further studies showed that A. mellifera sudanensis and A. florea do seem to coexist. This coexistence is based on different daily rhythms of pollen collection. A. mellifera collected pollen of Acacia seyal , date palm, and onions early in the morning (and partly in the late afternoon), while A. florea started pollen collection mostly later in the morning and ended it earlier in the afternoon. But in contrast to A. mellifera, A. florea was collecting pollen all day without interruption, even at very high air temperatures. Niche overlap (concerning the times of visits to flowers) between the two bee species was very low in date palms, and of medium importance in Acacia seyal . But it is remarkable that in total, A. florea is always present in higher numbers than A. mellifera sudanensis , on flowers. The significance of the introduction of A. florea to Sudan for pollination is discussed.     

Hydrolases in the hypopharyngeal glands of workers of Scaptotrigona postica and Apis mellifera (Hymenoptera, Apinae)

Hydrolytic enzymes from hypopharyngeal gland extracts of newly emerged, nurse and foraging workers of two eusocial bees, Scaptotrigona postica, a native Brazilian stingless bee, and the Africanized honey bee (Apis mellifera) in Brazil, were compared. The hypopharyngeal gland is rich in enzymes in both species. Fifteen different enzymes were found in the extracts, with only a few quantitative differences between the species. Some of the enzymes present in the extracts may have intracellular functions, while others seem to be digestive enzymes. Scaptotrigona postica, had lower beta-glucosidase and higher lipase esterase activities than A. mellifera. The differences may be due to different feeding habits and behavioral peculiarities of the two species.     

Characterization of recombinant and native Ih-channels from Apis mellifera

Recently, a novel class of genes coding for Ih-channels has been identified in several vertebrates and invertebrates. We isolated a cDNA (AMIH) encoding a putative member of these ion channels from Apis mellifera heads by means of polymerase chain reaction and homology screening. High similarity (88% identical amino acids) to the putative Drosophila melanogaster Ih-channel suggests that the Apis cDNA codes for a hyperpolarization-activated and cyclic nucleotide-gated channel. Functional expression of recombinant AMIH in HEK293 cells gave unitary currents that were preferentially selective for potassium over sodium ions and were activated by hyperpolarizing voltage steps. Cyclic nucleotides shifted the voltage activation curve to more positive membrane potentials. The current kinetics, activation by hyperpolarizing voltage steps and modulatory influence of cyclic nucleotides properties closely resemble those of mammalian Ih-channels. RT-PCR analysis showed pronounced mRNA expression in the antennae, head and body of Apis mellifera. Investigation of hyperpolarization-activated currents in olfactory receptor neurons (ORNs) in a primary cell culture of Apis mellifera antennal cells revealed activation properties similar to the heterologously expressed Ih-channel. By in-situ hybridization and immunohistochemistry, expression of AMIH was seen in olfactory receptor neurons of the bee antennae. We conclude that AMIH is the ion channel responsible for the hyperpolarization-activated currents in olfactory receptor neurons of bee.     

Monthly changes in various drone characteristics of Apis mellifera ligustica and Apis mellifera syriaca

This study was conducted to investigate drone rearing activity and semen production of Apis mellifera ligustica and Apis mellifera syriaca . Tendency of worker bees of both subspecies towards egg laying under semiarid conditions were also monitored in the experiments. Differences were not observed in drone brood production between both honeybee subspecies throughout the investigation. Worker bees of both subspecies needed a significantly shorter time to start egg laying during February and March in comparison with the time those workers needed for laying eggs during the remaining months of the study. Syrian bee workers started egg laying earlier than Italian bee workers. Drones from laying workers were much smaller and produced less sperms with more abnormalities than normal drones. Drones produced from queens in May were heavier and produced more sperms with less abnormalities than those produced during the other months. The drone brood rearing of both subspecies tended to follow the same general cycle in 2005 and 2006. The study suggests that virgin queens have a better chance to receive adequate viable sperm amounts from drones in April and May in semiarid Mediterranean conditions.     

Varying degrees of Apis mellifera ligustica introgression in protected populations of the black honeybee, Apis mellifera mellifera, in northwest Europe

The natural distribution of honeybee subspecies in Europe has been significantly affected by human activities during the last century. Non-native subspecies of honeybees have been introduced and propagated, so that native black honeybee (Apis mellifera mellifera) populations lost their identity by gene-flow or went extinct. After previous studies investigated the remaining gene-pools of native honeybees in France and Spain, we here assess the genetic composition of eight northwest European populations of the black honeybee, using both mitochondrial (restriction fragment length polymorphisms of the intergenic transfer RNAleu-COII region) and nuclear (11 microsatellite loci) markers. Both data sets show that A. m. mellifera populations still exist in Norway, Sweden, Denmark, England, Scotland and Ireland, but that they are threatened by gene flow from commercial honeybees. Both Bayesian admixture analysis of the microsatellite data and DraI-RFLP (restriction fragment length polymorphism) analysis of the intergenic region indicated that gene-flow had hardly occurred in some populations, whereas almost 10% introgression was observed in other populations. The most introgressed population was found on the Danish Island of Laeso, which is the last remaining native Danish population of A. m. mellifera and the only one of the eight investigated populations that is protected by law. We discuss how individual admixture analysis can be used to monitor the restoration of honeybee populations that suffer from unwanted hybridization with non-native subspecies.