Globally, honey bees are the most utilized animal pollinator in agriculture. However, fluctuations in honey bee colony availability have led to a demand for diversification among crop pollinators. Managed bumble bees are commercially available and highly efficient at pollinating many crops, including cranberries, yet utilization of these managed bees has remained relatively low in North America, with the cranberry industry remaining heavily reliant on honey bees. Here, we surveyed growers from Wisconsin (WI) and Quebec (QC), two of the world's largest cranberry producers, to assess their current crop pollination practices and attitudes regarding managed bumble bees as crop pollinators. To this end, we inquired about their farm demographics, usage of pollination practices, factors influencing those pollination practices, sources of information on crop pollination, and perceptions of managed bumble bees. QC respondents placed a greater importance on their relationships with beekeepers than WI respondents, while WI respondents were more concerned about fruit quality than QC respondents. QC respondents also stocked bumble bees and planted pollinator gardens at a higher percentage than WI respondents, believed that honey bees are more efficient pollinators of cranberry than bumble bees, and a greater proportion of QC respondents reported feeling well informed about bumble bees compared to WI respondents. Importantly, respondents in both regions rank bumble bees' ability to pollinate in inclement weather as their greatest benefit, and the costs of bumble bees as the greatest barrier to their use. We propose that trusted sources of pollination information in both regions, including university specialists, crop consultants, and beekeepers, are well suited to clarify misconceptions regarding bumble bee pollination.

The honey bee is associated with a diverse community of microbes (viruses, bacteria, fungi, and protists), commonly known as the microbiome. Here, we present data on honey bee microbiota from two localities having different surrounding landscapes – mountain (the Rhodope Mountains) and lowland (the Danube plain). The bacterial communities of abdomen of adult bees were studied using amplicon sequencing of the 16S rRNA gene. The composition and dominance structure and their variability within and between localities, alpha and beta diversity, and core and differential taxa were compared at different hierarchical levels (operational taxonomic units to phylum). Seven genera (Lactobacillus, Gilliamella, Bifidobacterium, Commensalibacter, Bartonella, Snodgrassella, and Frischella), known to include core gut-associated phylotypes or species clusters, dominated (92–100%) the bacterial assemblages. Significant variations were found in taxa distribution across both geographical regions and within each apiary. Lactobacillus (Firmicutes) prevailed significantly in the mountain locality followed by Gilliamella and Bartonella (Proteobacteria). Bacteria of four genera, core (Bartonella and Lactobacillus) and non-core (Pseudomonas and Morganella), dominated the bee-associated assemblages of the Danube plain locality. Several ubiquitous bacterial genera (e.g., Klebsiella, Serratia, and Providencia), some species known also as potential and opportunistic bee pathogens, had been found in the lowland locality. Beta diversity analyses confirmed the observed differences in the bacterial communities from both localities. The occurrence of non-core taxa contributes substantially to higher microbial richness and diversity in bees from the Danube plain locality. We assume that the observed differences in the microbiota of honey bees from both apiaries are due to a combination of factors specific for each region. The surrounding landscape features of both localities and related vegetation, anthropogenic impact and land use intensity, the beekeeping management practices, and bee health status might all contribute to observed differences in bee microbiota traits.

The role of bees in the environment, economic, biodiversity and pharmaceutical industries is due to its social behavior, which is oriented from the brain and hypopharyngeal gland that is the center of royal jelly (RJ) production. Limited studies have been performed on the head gene expression profile at the RJ production stage. The aim of this study was to compare the gene expressions in 9 and 1-day-old (DO) honeybee workers in order to achieve better understanding about head gene expression pattern. After sequencing of RNAs, transcriptome and their networks were compared. The head expression profile undergoes various changes. 1662 gene transcripts had differential expressions which 1125 and 537 were up and down regulated, respectively, in 9_DO compared with 1_DO honey bees. The day 1th had more significant role in the expression of genes related to RJ production as major RJ protein 1, 2, 3, 5, 6 and 9 encoding genes, but their maximum secretion occurred at day 9th. All process related to hypopharyngeal glands activities as CYP450 gene, fatty acid synthase gene, vitamin B6 metabolism and some of genes involved in fatty acid elongation and degradation process had an upward trend from 1_DO and were age-dependent. By increasing the age, the activity of pathways related to immune system increased for keeping the health of bees against the chemical compound. The expression of aromatic amino acid genes involved in Phenylalanine, tyrosine and tryptophan biosynthesis pathway are essential for early stage of life. In 9_DO honeybees, the energy supplying, reducing stress, protein production and export pathways have a crucial role for support the body development and the social duties. It can be stated that the activity of honeybee head is focused on energy supply instead of storage, while actively trying to improve the level of cell dynamics for increasing the immunity and reducing stress. Results of current study identified key genes of certain behaviors of honeybee workers. Deeper considering of some pathways will be evaluated in future studies.

Nosema apis and N. ceranae are the two causative agents of Nosema disease in adult honey bees (Apis mellifera L.). Nosema apis has been a recognized parasite for over a century and its epizootiology is well known. In contrast, N. ceranae is an emerging parasite of honey bees, which is now globally prevalent and the dominant Nosema spp. in many parts of the world. Despite this, many gaps in our knowledge exist regarding this species. For example, we do not fully understand all of the routes of transmission of N. ceranae among bees, or how long this parasite is capable of surviving in honey bee colonies. Here we investigated the viability and infectivity of N. ceranae spores in water and 2 M sucrose over time after storage at 33, 20, −12 and −20°C. Spores in both 2 M sucrose and water maintained high viability, except in water at −20°C over the course of the 6-week experiment. Infectivity was variable for spores after storage at all four temperatures, but all were infective at the last time point. The results provide evidence for cold tolerance and suggest that both water and 2 M sucrose (fall bee feed) could act as routes of transmission for N. ceranae. This work also contains information that may help influence management recommendations for the parasite.

Apis mellifera is infected by more than 24 virus species worldwide, mainly positive-sense, single-stranded RNA viruses of the Dicistroviridae and Iflaviridae families. Among the viruses that infect honey bees, Deformed wing virus is the most prevalent and is present as three master variants DWV-A, B, and C. Given that the ectoparasitic mite Varroa destructor vectors these virus variants, recombination events between them are expected, and variants and their recombinants can co-exist in mites and honeybees at the same time. In this study, we detect, through RT-qPCR, the presence of DWV-A and B in the same samples of adult bees from colonies of Argentina. Total RNA was extracted from pools of ten adult bees from 45 apiaries distributed across the main beekeeping Provinces of Argentina (Buenos Aires, Santa Fe, Córdoba, Santiago del Estero, Río Negro, and Mendoza); then RT-qPCR reactions were performed to detect DWV-A and B, with specific primer pairs. After the amplifications, PCR products (204 and 660 bp amplicons for DWV-B, and ~250 bp for DWV-A) were purified and sequenced to verify that they corresponded to reported sequences, analyzing them using the Blast software. Of the 45 samples analyzed by RT-qPCR, over 90% were infected with DWV-A and 47% were also positive for DWV-B, where it was found in high prevalence specifically in colonies of A. mellifera of the Buenos Aires Province. Future studies will determine the impact of this type of the virus and its ability to recombine with the other DWV types in the apiaries of our country.

Host shifts of parasites are often causing devastating effects in the new hosts. The Varroa genus is known for a lineage of Varroa destructor that shifted to the Western honey bee, Apis mellifera, with disastrous effects on wild populations and the beekeeping industry. Despite this, the biology of Varroa spp. remains poorly understood in its native distribution range, where it naturally parasitizes the Eastern honey bee, Apis cerana. Here, we combined mitochondrial and nuclear DNA analyses with the assessment of mite reproduction to determine the population structure and host specificity of V. destructor and Varroa jacobsonii in Thailand, where both hosts and several Varroa species and haplotypes are sympatric. Our data confirm previously described mite haplogroups, and show three novel haplotypes. Multiple infestations of single host colonies by both mite species and introgression of alleles between V. destructor and V. jacobsonii suggest that hybridization occurs between the two species. Our results indicate that host specificity and population genetic structure in the genus Varroa is more labile than previously thought. The ability of the host shifted V. destructor haplotype to spillback to A. cerana and to hybridize with V. jacobsonii could threaten honey bee populations of Asia and beyond.

Many factors, including pathogens, environmental change and breeding techniques, affect honeybee immunity/resistance, so substances and natural supplements that enhance it are desired. To eliminate the impact of unknown external factors, in 2016 a cage experiment was conducted under constant laboratory conditions (35 °C, 65% relative humidity). Bees in the control group were fed with sugar dissolved in water at ratio 1:1 ad libitum with no additives, while the other group was fed with sugar syrup (1:1) supplemented with piperine (3 µg/ml) ad libitum. The piperine-treated workers lived 9 days longer compared to the control group. In the piperine-consuming group, protein concentration and the activities of antioxidative enzymes, such as superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and glutathione S-transferase (GST), were higher than in the control group. The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were also higher in the piperine-treated group. Neutral and acidic proteases inhibitors, as well as neutral protease activities, were higher in the haemolymph of the piperine-treated workers than in untreated bees. Acidic protease activities in the haemolymph were higher in untreated workers only on days 18 and 32. Alkaline protease activities in the control bees were higher from day 10. From 10 days old, the total antioxidant capacity level was significantly higher in the haemolymph of piperine-treated workers. Piperine decreased DNA methylation levels significantly in the older bees. The compound could have the potential to be a natural diet supplement increasing apian resistance to stress factors.

Varroa destructor mites (Acari: Varroidae) are harmful ectoparasites of Apis mellifera honey bees. Female foundresses of wax-capped pupal host cells and their daughters feed on host fluids from open wounds on the host's integument. Details of V. destructor mite nutrition are forthcoming, and little is known about the potential physical effects on hosts from mite feeding. Chemical analysis of waste excretions can infer details of animals’ nutrition. Here, chemical analysis by high-performance liquid chromatography/mass spectrometry (HPLC-MS/MS) of mite excretions showed that the purine content of V. destructor waste consists of guanine with traces of hypoxanthine. Traces of uric acid and caffeine were also detected. Concentrations of guanine attenuated over time and excretions collected from senescing mites did not contain detectable guanine. Non-reproducing individual female mites maintained in vitro, housed in gelatin capsules and provided a honey bee pupa, deposited an average of nearly 18 excretions daily, mostly on the host's integument rather than on the capsule wall. The weight and volume of excretions suggest mites can consume nearly a microlitre of host fluids each day. Compounded over 10 days, this together with open wounds, could lead to substantial water loss and stress to developing pupae.

In social insects such as the honey bee, the quality of drones at the time of their emergence can affect their maintenance in the colony until maturity. Body mass, wing size and wing asymmetry of emerging honey bee drones were measured and correlated with their life span in the colony and compared between individuals reaching maturity or not. The life span of drones differed among colonies in which they were maintained after emergence but not between colonies in which they were reared. More drones heavier at emergence reached sexual maturity at 15 days and had a longer life span compared with light-weight drones of lower mass. The size and symmetry of drone forewings was not correlated with their life span. Our results suggest that body mass at emergence is a good predictor of drone survival in the colony.

Interspecific kleptoparasitism (the stealing of already-procured items from other species) has received little attention in tropical reptiles. We report here the second case of kleptoparasitism in tropical lizards, and the first known case of pollen theft by a vertebrate species. Phelsuma inexpectata, a gekkonid lizard endemic to Réunion, was observed robbing pollen pellets from honeybees (Apis mellifera) foraging on Latania lontaroides flowers. Video-records were used to obtain reliable information on gecko-honeybee interactions occurring on L. lontaroides inflorescences. During the 19 observation periods (total duration 140 min) a total of 78 attempts were recorded, at least 40% were successful. Both males and females displayed kleptoparasitic behaviour. A high level of gecko kleptoparasitism occurred, with an average one-robbery attempt every 2 min. Behaviour of both the kleptoparasitic P. inexpectata and its host A. mellifera are described.

Hurricanes are major disturbance events in Neotropical mangrove communities, potentially affecting the reproductive success of mangrove species. This was the first investigation of changes in mangrove pollinator assemblages following hurricanes, and the effect of these changes on the mating system of Laguncularia racemosa. Insect pollinator assemblages were investigated in three Florida mangrove communities in 2001–2003, 2005 and 2009; two hurricanes affected the area in 2004. Visitation rates were estimated from 1445 insects observed during 272 10-min intervals; the number of flowers visited by each insect was also recorded. Pollinator diversity was estimated with the Shannon Index. Following the hurricanes, species richness was reduced by 43–65% and diversity declined by 36–70%. Significant declines in insect visitation to L. racemosa resulted in reduced outcrossing frequencies in 2005. Laguncularia racemosa flowers autogamously self-pollinate without insect visitors, so fruit set still occurred. Visitation rates returned to pre-hurricane levels by 2009, but foraging behaviours differed from pre-hurricane patterns; outcrossing was further favoured by reduced frequencies of long foraging bouts and increased frequencies of short foraging bouts. The mixed mating system of L. racemosa provides reproductive assurance following hurricane disturbances, when pollinator abundance is low.

Chagas disease chemotherapy is based on drugs that exhibit toxic effects and have limited efficacy, such as Benznidazole. Therefore, research into new chemotherapeutic agents from natural sources needs to be exploited. Apis mellifera venom consists of many biologically active molecules and has been reported to exhibit remarkable anti-cancer effects, often promoting an apoptosis-like death phenotype. This study demonstrates that A. mellifera venom can affect the growth, viability and ultrastructure of all Trypanosoma cruzi developmental forms, including intracellular amastigotes, at concentrations 15- to 100-fold lower than those required to cause toxic effects in mammalian cells. The ultrastructural changes induced by the venom in the different developmental forms led us to hypothesize the occurrence of different programmed cell death pathways. Autophagic cell death, characterized by the presence of autophagosomes-like organelles and a strong monodansyl cadaverine labelling, appears to be the main death mechanism in epimastigotes. In contrast, increased TUNEL staining, abnormal nuclear chromatin condensation and kDNA disorganization was observed in venom-treated trypomastigotes, suggesting cell death by an apoptotic mechanism. On the other hand, intracellular amastigotes presented a heterogeneous cell death phenotype profile, where apoptosis-like death seemed to be predominant. Our findings confirm the great potential of A. mellifera venom as a source for the development of new drugs for the treatment of neglected diseases such as Chagas disease.

Insect-pollinated Laguncularia racemosa has a variable breeding system; some populations are androdioecious, with male and hermaphroditic plants, while others lack male plants. We observed the foraging behaviours of insects in three androdioecious and three hermaphrodite-only populations of L. racemosa in Florida. In each population, insect visitation rates were estimated from 30–108 timed intervals. We recorded the number of flowers visited by 144–224 insects during foraging bouts made to 15–40 male and hermaphroditic plants. Male plants in androdioecious populations had significantly more visitors than hermaphroditic plants, increasing the number of vectors carrying pollen from male plants. Further, many insects visited few flowers during foraging bouts, which should increase outcrossing frequency. According to mathematical models, male plants benefit from these combined factors. Plants in hermaphrodite-only populations had significantly more visitors than hermaphroditic plants in androdioecious populations. Proportionately more insects visited many flowers during foraging bouts in hermaphrodite-only versus androdioecious populations. The increased likelihood of geitonogamous self-pollination could help explain the lack of male plants in hermaphrodite-only populations. Differences in pollinator assemblages and the relative abundances of several species were responsible for differences in foraging behaviours: Apis mellifera, Bombus sp., Melissodes sp., Xylocopa sp., Euodynerus sp. and a calliphorid species.

Pollinator visits to flowers of self-incompatible tropical trees are critical for plant fecundity. However, few studies have examined how much of the variance in tropical tree fecundity is explained by individual attributes of trees (e.g. number of flowers), and how much is due to contextual variables such as distances to nearest flowering neighbours. Using multiple regressions we examined the relative contributions of these factors to the pollination and fecundity of Goetzea elegans, a mainly self-incompatible tree endemic to Puerto Rico. We studied the largest wild population of the species during the peak flowering and collected data on the frequency of pollinator visits (N = 25 trees), and the fecundity of the whole population (N = 105), including the visitation rate of two pollinators (the honey bee Apis mellifera and the bananaquit Coereba flaveola), the total number of flowers produced by each tree, and the total fruit set and seed viability per tree. We also recorded the distance to flowering conspecifics and heterospecifics, and the height for each tree. Flower number had a strong positive effect on pollinator visitation, but distance to nearest neighbours was equally or more important than flower number in influencing fecundity. Also, competition for limited pollinators between G. elegans and other species has a stronger effect than the facilitation that conspecifics may provide. Our results suggest that pollinator visits and aspects of fecundity of G. elegans depend both on the attributes of individual plants, and on those of the community of other nearby plants.

Visual systems can undergo striking adaptations to specific visual environments during evolution, but they can also be very “conservative.” This seems to be the case in motion vision, which is surprisingly similar in species as distant as honeybee and goldfish. In both visual systems, motion vision measured with the optomotor response is color blind and mediated by one photoreceptor type only. Here, we ask whether this is also the case if the moving stimulus is restricted to a small part of the visual field, and test what influence velocity may have on chromatic motion perception. Honeybees were trained to discriminate between clockwise- and counterclockwise-rotating sector disks. Six types of disk stimuli differing in green receptor contrast were tested using three different rotational velocities. When green receptor contrast was at a minimum, bees were able to discriminate rotation directions with all colored disks at slow velocities of 6 and 12 Hz contrast frequency but not with a relatively high velocity of 24 Hz. In the goldfish experiment, the animals were trained to detect a moving red or blue disk presented in a green surround. Discrimination ability between this stimulus and a homogenous green background was poor when the M-cone type was not or only slightly modulated considering high stimulus velocity (7 cm/s). However, discrimination was improved with slower stimulus velocities (4 and 2 cm/s). These behavioral results indicate that there is potentially an object motion system in both honeybee and goldfish, which is able to incorporate color information at relatively low velocities but is color blind with higher speed. We thus propose that both honeybees and goldfish have multiple subsystems of object motion, which include achromatic as well as chromatic processing.

The parasitic mite, Varroa destructor, is the most important threat for apiculture in most bee-keeping areas of the world. The mite is carried to the bee brood cell, where it reproduces, by a nurse bee; therefore the selection of the bee stage by the parasite could influence its reproductive success. This study investigates the role of the cuticular hydrocarbons of the European honeybee (Apis mellifera) in host-selection by the mite. Preliminary laboratory bioassays confirmed the preference of the varroa mite for nurse bees over pollen foragers. GC-MS analysis of nurse and pollen bees revealed differences in the cuticular hydrocarbons of the two stages; in particular, it appeared that pollen bees have more (Z)-8-heptadecene than nurse bees. Laboratory experiments showed that treatment of nurse bees with 100 ng of the pure compound makes them repellent to the varroa mite. These results suggest that the mite can exploit the differences in the cuticular composition of its host for a refined selection that allows it to reach a brood cell and start reproduction. The biological activity of the alkene encourages further investigations for the development of novel control techniques based on this compound.

Varroa mites (Varroa destructor) are serious ectoparasites of honey bees (Apis mellifera). This research addresses the impact of varroa mites on survivorship, viral incidence, and physiological traits of newly-emerged worker bees. RT-PCR confirmed our previous finding that varroa parasitization was linked to high levels of deformed wing virus (DWV). In non-treatment bees, varroa parasitization combined with increased viral levels altered survivorship curves from long-survival to shorter-survival types. After challenge with live Escherichia coli, the survivorship of mite-parasitized bees was significantly lower than mite-free bees. Deformed-wing, mite-parasitized bees died on average within 1 day, even without E. coli challenge. This was correlated with the absence of an important enzyme activity in insect immunity, phenol oxidase, lacking even in those bees challenged with immuno-elicitors. The lack of inducible phenol oxidase activity indicated that the bee immune system is not fully competent upon adult emergence. Varroa parasitism also significantly reduced body weight of the parasitized bees, but body weight was not significantly correlated with the survivorship of mite-parasitized bees. Our research indicates that the combination of mite parasitization, the interaction of DWV and microbes, and a developmental immune incompetency attribute to decreased worker survivorship and have a negative impact on colony fitness.

Investigations into the potential impacts of selectively managing Apis mellifera on pollination ecology were carried out in several sites in Tsavo National Park of southern Kenya, a typical arid African environment. Temperature alone contributed significantly to the foraging patterns of both managed honeybees and wild bee species within the acacia–commiphora community. Honeybees, vulnerable to heat stress, foraged earlier in the day than wild bee species. Foraging patterns of the latter ranged from oligolectic to broadly non-specialized. Floral biology and adaptations were also considered in the analysis of divergent foraging trends. Observations suggest that honeybees potentially out-compete highly specialized wild bee species for scarce seasonal floral resources. No evidence was found of direct interaction on abundant seasonal floral resources such as the mass synchronous flowering of Acacia spp. at current managed honeybee densities. Investigation of visitors revealed a high diversity of potential insect pollinators, particularly high in wild bee species (Apoidea) diversity. Suggestions for the improved management of honeybees in arid African environments include shading of hives, providing access to water with protection from predators, and cultivation of indigenous, nectariferous plants close to hive colonies.

Pollination ecology was investigated in Citrullus lanatus (Thunb.) Matsum. & Nakai, which is a species vulnerable to pollinator loss. It was found that this species depends heavily on the honeybee, Apis mellifera L., as the main pollinator. Other pollen vectors identified include Xylocopa bees, halictid bees, Hypotrigona bees, flies and beetles. Phenologically, the plant was found to promote male fitness by producing numerous male flowers, which serve as pollinator attracting structures. Blooming sequence and A. mellifera visitation rates to these flowers are presented. This will enable farmers and pollination managers to better understand visitation patterns and to safeguard pollinators during pesticide application schedules.