Bee Populations Research Articles

The Potential of Agaricus bisporus in Mitigating Pesticide-Induced Oxidative Stress in Honey Bees Infected with Nosema ceranae

Global climate change, environmental pollution, and frequent pesticide use severely reduce bee populations, greatly challenging beekeeping. Pesticides such as deltamethrin, a pyrethroid insecticide commonly used to control mosquitoes, can kill individual bees and entire colonies, depending on the exposure. Due to mosquito resistance to pyrethroid insecticides, components that enhance their effect are commonly used. This study explores the potential of Agaricus bisporus mushroom extract in mitigating oxidative stress in bees triggered by pesticides and Nosema ceranae infection. Our findings indicate that A. bisporus extract significantly reduced mortality rates of bees and spore counts of N. ceranae. Furthermore, the extract demonstrated antioxidant properties that lower enzyme activity related to oxidative stress (CAT, SOD, and GST) and MDA concentration, which is linked to lipid peroxidation. These results indicate that natural extracts like A. bisporus can aid bee health by mitigating the effects of pesticides and pathogens on honey bees, thus improving biodiversity.

Ecological Role of Spiders in Terrestrial Ecosystem and Their Conservation Priorities

Spiders are members of the phylum Arthropoda, the largest phylum of animal groups in the world under the class Arachnida. Spiders are ubiquitous in distribution, invade almost every type of habitat, and are the most abundant invertebrate predators in terrestrial ecosystems. Nearly 47,617species of spiders under 4,092 genera in 114 families were recorded in the world. Spiders are a key component of terrestrial ecosystems, occupying a unique position in food webs. As predators, they are important in the regulation of invertebrate populations, which include pest species, and as prey, they provide food for other invertebrates and birds. They are important components of the food chain. This is not withstanding the contribution they make to ecosystems in their own right.Spider silk has unique properties that have potential applications in medicine and technology. Many species of spiders have been used as medicines. As bee populations plummet, spiders might be the next solution to the pollination process. Spiders are among the most fascinating creatures on earth, and their importance in scientific research cannot be overstated. Spiders play a critical role in maintaining ecological balance, and studying their behavior and biology can greatly advance our understanding of the natural world. The witnessing role of spiders in terrestrial ecosystems has made them ecologically important. In the past few years, spiders have faced several threats that have affected their populations and diversity. Prior conservation programs are required to protect this species from being more vulnerable and endangered.

Robust pollination for tomato farming using deep learning and visual servoing

Abstract In this work, we propose a novel approach for tomato pollination that utilizes visual servo control. The objective is to meet the growing demand for automated robotic pollinators to overcome the decline in bee populations. Our approach focuses on addressing this challenge by leveraging visual servo control to guide the pollination process. The proposed method leverages deep learning to estimate the orientations and depth of detected flower, incorporating CAD-based synthetic images to ensure dataset diversity. By utilizing a 3D camera, the system accurately estimates flower depth information for visual servoing. The robustness of the approach is validated through experiments conducted in a laboratory environment with a 3D printed tomato flower plant. The results demonstrate a high detection rate, with a mean average precision of 91.2 %. Furthermore, the average depth error for accurately localizing the pollination target is impressively minimal, measuring only 1.1 cm. This research presents a promising solution for tomato pollination, showcasing the effectiveness of visual-guided servo control and its potential to address the challenges posed by diminishing bee populations in greenhouses.

Gene Flow Between Populations With Highly Divergent Mitogenomes in the Australian Stingless Bee, Tetragonula hockingsi.

Coadaptation of mitochondrial and nuclear genes is essential for proper cellular function. When populations become isolated, theory predicts that they should maintain mito-nuclear coadaptation in each population, even as they diverge in genotype. Mito-nuclear incompatibilities may therefore arise when individuals from populations with divergent co-evolved mito-nuclear gene sets are re-united and hybridise, contributing to selection against inter-population hybrids and, potentially, to speciation. Here, we explored genetic divergence and gene flow between populations of a stingless bee (Tetragonula hockingsi) that have highly divergent mitogenomes. We identified three distinct populations across the species' 2500 km range on the east coast of Queensland (Australia): 'Cape York', 'Northern', and 'Southern'. The mitogenomes of each population showed > 12% pairwise nucleotide divergence from each other, and > 7% pairwise amino acid divergence. Based on nuclear SNPs from reduced representation sequencing, we identified at least two zones of gene flow between populations: a narrow natural zone between Northern and Southern populations (coinciding with a biogeographic barrier, the Burdekin Gap), and an artificial zone at the southern edge of the species' distribution, where Cape York, Northern, and Southern mito-lineages have been brought together in recent decades due to beekeeping. In the artificial hybrid zone, we also confirmed that males of all three mito-lineages were attracted to the mating aggregations of Southern queens, consistent with inter-population hybridisation. Populations of T. hockingsi thus appear to be in the 'grey zone' of the speciation continuum, having strong genetic differentiation but incomplete reproductive isolation. Among the nuclear SNPs most differentiated between Northern and Southern populations, several were associated with genes involved in mitochondrial function, consistent with populations having co-diverged mito-nuclear gene sets. Our observations suggest that coadapted sets of mitochondrial and nuclear genes unique to each population of T. hockingsi may play a role in maintaining population boundaries, though more study is needed to confirm the fitness costs of mito-nuclear incompatibilities in hybrid individuals.

Artificial intelligence-driven tool for spectral analysis: identifying pesticide contamination in bees from reflectance profiling

Pesticide poisoning constantly threatens bees as they forage for resources in pesticide-treated crops. This poisoning requires thorough investigation to identify its causes, underscoring the importance of reliable pesticide detection methods for bee monitoring. Infrared spectroscopy provides reflectance data across hundreds of spectral bands (hyperspectral reflectance), presumably enabling the efficient classification of pesticide contamination in bee carcasses using artificial intelligence (AI) models, such as machine learning. In this study, bee contamination by commercial formulations of three insecticides—dimethoate (organophosphate), fipronil (phenylpyrazole), and imidacloprid (neonicotinoid)—as well as glyphosate, the most widely used herbicide globally, was detected using machine learning models. These models classified the hyperspectral reflectance profiles of the body surfaces of contaminated bees. The best-performing model, the linear discriminant analysis, achieved 98% accuracy in discriminating contamination across species Apis mellifera, Melipona mondury, and Partamona helleri, with prediction speeds of 0.27seconds. Our pioneering study introduced an effective method for discerning multiple classes of bees contaminated with pesticides using hyperspectral reflectance. An AI-driven spectral data analysis tool (https://github.com/bernardesrodrigoc/MACSS) was developed for the purpose of identifying and characterizing new samples through their spectral characteristics. This platform aids efforts to monitor and conserve bee populations and holds potential importance in environmental monitoring, agricultural research, and industrial quality control.

Managing the parasitic honey bee mite Tropilaelaps mercedesae through combined cultural and chemical control methods

The western honey bee (Apis mellifera) is severely impacted by the parasitic Tropilaelaps mercedesae mite, which has the capacity to outcompete Varroa destructor mites (the current leading cause of colony losses) and more rapidly overwhelm colonies. While T. mercedesae is native to Asia, it has recently expanded its geographic range and has the potential to devastate beekeeping worldwide if introduced to new regions. Our research exploited the dependence of T. mercedesae on developing honey bees (brood) by combining a cultural technique (brood break) with U.S. registered chemical products (oxalic acid or formic acid) to manage T. mercedesae infestation. To evaluate this approach, we compared four treatment groups: (1) Brood Break; (2) Brood Break + Formic Acid (FormicPro®); (3) Brood Break + Oxalic Acid dribble (Api-Bioxal®); and (4) untreated Control. We found that the mite infestation rate of worker brood in Control colonies rose from 0.4 to 15.25% over 60 days, whereas all other treatment groups had infestation rates under 0.11% on Day 60. Mite fall assessments showed similar results, whereby Control colonies had 15.48 mites fall per 24 h on day 60 compared to less than 0.2 mites for any other treatment group. Evaluation of colony strength revealed that Brood Break + Formic Acid colonies had slightly reduced adult honey bee populations. No treatment eliminated all mites, so additional measures may be needed to eradicate T. mercedesae if detected in countries that do not currently have T. mercedesae.

Knowledge, attitude, and perceptions of farmers in the Maranhão Amazon regarding the ecological importance of bees

Bees perform an essential pollination service on more than half of all plants worldwide. However, a global decline in bee and other pollinator populations due to anthropic activities threatens these services. Understanding the interactions between farmers and bees is essential for developing policies to protect pollinators. This study sought to investigate and document the knowledge, attitudes, and perceptions of farmers in the Maranhão Amazon in Brazil regarding the relevance and function of bees. Semi-structured interviews were conducted with 567 farmers from 54 rural communities, located in six counties. The results showed that participating farmers understood the importance of bees, acknowledging the pollination of plants and honey production as their primary functions. Farmers also observed that bee populations have reduced over the years and cited anthropic actions (deforestation, slash-and-burn agriculture, and pesticide use) as the most impacting elements. Although farmers recognized the ecological functions of bees, none were willing to implement any novel practices on their properties to preserve bee populations. Our results identified a need to stimulate the implementation of activities that safeguard bees, for instance via projects that train local farmers and encourage them to contribute to bee preservation, implement sustainable agricultural practices, and reduce pesticide use. Such projects can assist farmers in the recovery and reforestation of degraded areas in the region.

The impact of landscape structure on pesticide exposure to honey bees

Pesticides may have serious negative impacts on bee populations. The pesticide exposure of bees could depend on the surrounding landscapes in which they forage. In this study, we assess pesticide exposure across various land-use categories, while targeting the Japanese honey bee, Apis cerana japonica, a native subspecies of the eastern honey bee. In a project involving public participation, we measured the concentrations of major pesticides in honey and beeswax collected from 175 Japanese honey bee colonies across Japan and quantitatively analyzed the relationships between pesticide presence/absence or pesticide concentration and land-use categories around the colonies. Our findings revealed that the surrounding environment in which bees live strongly influences pesticide residues in beehive materials, whether the pesticides are systemic or not, with a clear trend for each land-use category. Agricultural lands, particularly paddy fields and orchards, and urban areas resulted in higher pesticide exposure, whereas forests presented a lower risk of exposure. To effectively control pesticide exposure levels in bees, it is essential to understand pesticide usage patterns and to develop appropriate regulatory systems in non-agricultural lands, similar to those in agricultural lands.

Spatiotemporal variability and foraging behavior of bee visitors to a rare long-lived iteroparous forb, Silene spaldingii (Caryophyllaceae).

Silene spaldingii S Watson is a rare long-lived forb (Caryophyllaceae) found primarily in open native grasslands of the Inland Pacific Northwest and is putatively pollinated by one key bumble bee pollinator, Bombus fervidus (Fabricius). However, populations of bumble bees and their visitation patterns can vary dramatically, and some species are in decline including B. fervidus. Understanding the role of co-pollinators such as sweat bees (Halictidae) could be crucial as the plight of rare plants and pollinators intensifies. We collected data across three seasons (2015-2017) on the Bombus-S. spaldingii pollination system, focusing on three Key Conservation Areas in the Channeled Scablands of eastern Washington. Bee visitors to S. spaldingii were monitored and the pool-of-pollinators was surveyed with blue vane traps. Nine species of bees were observed foraging on the plant, while 2211 bees comprised of five families, 22 genera and 81 taxa were captured in blue vane traps, meaning only 11.1% of species in the pollinator pool visited S. spaldingii. Halictus tripartitus Cockerell, a sweat bee, was a common visitor to the plant, but this was the first record of visitation for several other species, including Lasioglossum buccale (Pérez) which has never before been recorded in the Americas. These sweat bees appear to vector S. spaldingii pollen, suggesting they are co-pollinators of the plant. Weather and patch characteristics affected visitation patterns and the pool-of-pollinators. We conclude that sweat bees are likely co-pollinators of S. spaldingii and that they could become increasingly important if B. fervidus populations continue to decline.

Drone Congregation areas of Apis mellifera (hymenoptera: apidae) and Nosema sp. (nosematidae) in Bolivia: first report

Drone Congregation Areas (DCAs) are crucial natural gathering sites for Apis mellifera mating, like male leks in other animals. In these areas, virgin queens and drones from various hives congregate for mating, promoting genetic variability essential for colony adaptation and survival. Identifying drones in DCAs helps to understand the genetic variability within bee populations, which is crucial for promoting colony survival and resilience. Two areas in Villa Montes, Bolivia, were identified as potential DCAs through exploration methods utilizing satellite imagery. Furthermore, drones were captured within these DCAs using an attractive pheromone attached to an unmanned aerial vehicle to assess Nosema infection in the population.

Neonicotinoids, Agriculture And Food Security Of Brazilian Honey: A Review

Pesticides used in agriculture have the function of controlling pests, diseases and preventing the development and growth of weeds, increasing the quality and productivity of crops. However, when they reach unwanted targets, such as bees, humans and other living beings, they cause harmful damage to ecosystems. Neonicotinoids, insecticides widely used in monocultures, such as soybeans and corn in Brazil, are especially harmful to bees, whether native or exotic, interfering with the foraging and pollination performance of plants. The global decline in the bee population is related to the use of insecticides, a fact that directly threatens the production of various foods. Honey, the main beekeeping product , is not only a source of food for bees, humans and other animals, but also an indicator of environmental quality, as its composition reflects the conditions of the environment in which it was produced, and determinations made therein can reveal the presence of contaminants such as pesticides and toxic metals providing information about ecosystem health and the presence of environmental contaminants. Furthermore, consuming pesticide-free foods is crucial for human health and environmental sustainability, as the intake of neonicotinoids is associated with several health problems such as hormonal disorders and nervous system diseases and is especially dangerous for children. This article reviews the neonicotinoid insecticides imidacloprid and thiamethoxam and the contamination they cause in the honey of bees Apis mellifera Linnaeus (1758) and Tetragonisca angustula Latreille (1811) in Brazil, evaluating the impacts of these insecticides on bees, the implications for ecosystems and safety to feed

Sublethal exposure to thiamethoxam and pyraclostrobin affects the midgut and Malpighian tubules of the stingless bee Frieseomelitta varia (Hymenoptera: Apidae: Meliponini).

The stingless bee Frieseomelitta varia Lepeletier 1836 (Hymenoptera: Apidae) is an essential pollinator in natural and agricultural ecosystems in the Neotropical region. However, these bees may be exposed to pesticides during foraging, which can affect both individuals and their colonies. One example comes from the use of pyraclostrobin (a fungicide) and thiamethoxam (an insecticide) for pest control in pepper crops, which F. varia visits. This study aimed to evaluate the isolated and combined sublethal effects of thiamethoxam (TMX) (0.000543 ng a.i./µL) and pyraclostrobin (PYR) (1.5 ng i.a./µL) on the morphology of the midgut and Malpighian tubules of F. varia workers. Results showed that both pesticides, regardless of the exposure time (through feeding during 48 h or 96 h), disturbed the morphology of the analyzed organs. Specifically, F. varia exposed orally to sublethal concentrations of thiamethoxam and pyraclostrobin, either alone or in combination, exhibited a higher rate of damage to the midgut (e.g., vacuolization, apocrine secretion, and cellular elimination) compared to the bees in the control groups, both after 48 h and 96 h of exposure. In Malpighian tubules, vacuolation is the only damage present. As the observed morphological alterations likely compromise the excretion and absorption functions, exposure to pyraclostrobin and thiamethoxam may lead to disturbances at both the individual and colony levels. These results highlight the urgent need for a future reassessment of the safety of fungicides and insecticides regarding their potential effects on bee populations.

Conventional agriculture affects sex communication and impacts local population size in a wild bee

Man-made agricultural stressors have been identified to compromise the reproductive dynamics of bee populations within agricultural environments. With the aid of bee hotels, we explored the influence of conventional and organic farming systems on local population size and body traits of the mason bee, Osmia bicornis, in southern Germany. We further used a chemical ecology approach and bioassays to test whether farming management influence male pre-copulatory behaviors. We observed a positive relationship between the extent of organic agriculture in the landscape and both overall brood cell production and nesting frequency. Moreover, farming systems were found to influence body traits, with bees from organic sites being smaller in size and having a different cuticular hydrocarbon composition compared with those at conventional sites. Bioassays revealed that males were more sexually attracted to freeze-killed females from conventional sites compared with those from organic sites. Intriguingly, treating females from organic fields with synthetic semiochemicals enhanced their sexual attraction to levels comparable with females from conventional sites. Our findings shed light on the intricate interplay between farming practices and the reproductive behaviors of wild mason bees, emphasizing the need for a comprehensive understanding of these dynamics for effective conservation and management strategies.

Multivariate optimization of the extraction and cleaning procedure to determine neonicotinoids in honey from intensive livestock and agricultural production areas by UHPLC-MS/MS

Neonicotinoid insecticides have been associated with the decline of bee population. This study aimed to investigate the occurrence of neonicotinoids in honey samples from apiaries located in areas of intensive livestock and agricultural production in Argentina. For this purpose, a QuEChERS-based analytical method was developed and optimized using multivariate strategies to reduce the processing time and the necessary amount of salts and sorbents. Validation was based on SANTE 11312/2021 guidelines, with recovery percentages between 79 and 120 %, and limits of quantitation between 0.25 and 1.00 µg kg−1. The present study provides a highly sensitive and reliable method for ascertaining residue levels of eight insecticides in 151 honey samples using liquid chromatography coupled to mass spectrometry (UHPLC-MS/MS). The presence of three of the target analytes was determined in 13 % of the samples, indicating that honey bee colonies were exposed to neonicotinoids, especially imidacloprid and thiamethoxam. The maximum residue limits were not exceeded in any of the samples; therefore, there is no risk to consumers from the public health point of view.

Population Dynamics of the Mite Varroa destructor in Honey Bee (Apis mellifera) Colonies in a Temperate Semi-Arid Climate.

This study aimed to analyze the population dynamics of the mite Varroa destructor in honey bee (Apis mellifera) colonies in a temperate semi-arid climate in Mexico. Ten colonies homogeneous in population, food stores, and levels of mite infestation were used. The mite infestation rate in brood and adult bees, total number of mites, daily mite fall, brood and adult bee population, and food stores were determined periodically for 10 months. There was a significant effect (p < 0.05) of sampling period on the population of V. destructor in adult bees, brood, total mite population, and daily fallen mites. The total mite population increased by 26% on average per colony. The increase in brood amount reduced the mite infestation rate in adult bees, and the opposite occurred when the brood decreased. Monitoring V. destructor populations by recording fallen mites is more reliable than determining mite infestation rates in bees, as mite fall has a dynamic pattern similar to that of the total mite population. The best period to apply an acaricide treatment in the region of study is between November and December because most mites were in the phoretic phase, since there was less brood in the colonies compared to other times.

The impact of buckwheat and paulownia (Paulownia elongata × P. fortunei) intercropping on beekeeping value and buckwheat yield

Increasing crop diversity is a way for agriculture to transition towards a more sustainable and biodiversity-friendly system. Growing buckwheat intercropped with paulownia can contribute not only to mitigating climate change but can also enrich the environment with species of agricultural importance, without causing a decline in pollinators, since buckwheat is pollinated mainly by the honeybee. In a field experiment comparing growing buckwheat with paulownia against a monoculture crop, we investigated differences in flower visitation and beekeeping value, as well as the associated impact on crop yields. We analysed the effect of intercropping on the beekeeping value of buckwheat in terms of bee population size and the sugar mass in buckwheat flowers, nectar mass in buckwheat flowers, the quality of the delivered raw sugar and biometric characteristics. We found significant differences in the number of branches on the main shoot and the total number of branches. Significantly higher parameters were obtained in sites with buckwheat monoculture. The cultivation method variant did not cause differentiation in either the structure elements or the yield itself. Yields ranged from 0.39 (2021) to 1.59 (2023) t·ha−1. The average yield in intercropping was slightly lower (0.02 t·ha−1) than in the monoculture system of buckwheat (0.93 t·ha−1). More flowers per plant per day of observation and more flowers in millions of flowers per hectare per day of observation were observed in the intercropping of buckwheat with paulownia. Based on our experiment, we concluded that growing buckwheat in monoculture significantly increased the number of flowers, resulting in an increase in pollinator density and an increased number of pollinators per unit area.

Bumble bees do not avoid field-realistic but innocuous concentrations of cadmium and copper.

Bee populations are facing numerous stressors globally, including environmental pollution by trace metals and metalloids. Understanding whether bees can detect and avoid these pollutants in their food is pivotal, as avoidance abilities may mitigate their exposure to xenobiotics. While these pollutants are known to induce sublethal effects in bees, such as disrupting physiological mechanisms, their potential impacts on locomotive abilities, fat metabolism, and reproductive physiology remain poorly understood. In this study, utilising workers of the buff-tailed bumble bee and two prevalent trace metals, namely cadmium and copper, we aimed to address these knowledge gaps for field-realistic concentrations. Our findings reveal that workers did not reject field-realistic concentrations of cadmium and copper in sucrose solutions. Moreover, they did not reject lethal concentrations of cadmium, although they rejected lethal concentrations of copper. Additionally, we observed no significant effects of field-realistic concentrations of these metals on the walking and flying activities of workers, nor on their fat metabolism and reproductive physiology. Overall, our results suggest that bumble bees may not avoid cadmium and copper at environmental concentrations, but ingestion of these metals in natural settings may not adversely affect locomotive abilities, fat metabolism, or reproductive physiology. However, given the conservative nature of our study, we still recommend future research to employ higher concentrations over longer durations to mimic conditions in heavily polluted areas (i.e., mine surrounding). Furthermore, investigations should ascertain whether field-realistic concentrations of metals exert no impact on bee larvae.

Genomic diversity and population structure of Carniolan honey bee in its native habitat

BackgroundResearch into the genetic diversity of honey bee (Apis melliferaL.) populations has become increasingly significant in recent decades, primarily due to population declines attributed to human activities and climate change. As a species of great importance, breeding programs that leverage understanding of genomic diversity could offer solutions to mitigate these challenges. The objective of this study was to examine the genomic diversity and population structure of Carniolan honey bees (Apis mellifera carnica) using the Illumina SNP chip on a large honey bee sample collected from Central and South-Eastern European countries. The study also aims to offer recommendations for future breeding programs.ResultsOur analysis involved Discriminant Analysis of Principal Components (DAPC), heterozygosity, admixture analysis, fixation indices (FST), Neighbour-Joining tree, gene flow and Isolation-by-distance analysis. DAPC indicated distinct separation between the Carniolan and Italian honey bee (Apis mellifera ligustica) populations, whereas the admixture analysis revealed varying levels of gene flow and genetic admixture within the Carniolan honey bee populations, demonstrating closer relationships between specific geographic regions (confirmed by Isolation-by-distance analysis). Furthermore, the research of heterozygosity, genomic inbreeding, pairwise FST values, and Neighbour-Joining tree provided insights into the patterns of genetic differentiation and similarity among the populations of Carniolan honey bee within its natural habitat. We have observed genetic homogeneity of the Carniolan honey bee population when considered in a broader genetic/geographical context. However, the Carniolan honey bee has sufficient genetic diversity in its geographical home range that needs to be carefully monitored and maintained.ConclusionsThis study provides important insights into the genetic composition, differentiation, and relationships among Carniolan honey bee populations in Central and South-Eastern European countries. The findings are crucial for conservation efforts, breeding programs, and sustainable beekeeping practices. They emphasise the importance of considering genetic factors and population structure in the breeding and management of honey bees. By understanding these genetic relationships, we can develop strategies to preserve genetic diversity, improve breeding outcomes, and ensure the resilience of honey bee populations in the face of environmental changes and challenges. This knowledge can also inform policy makers and stakeholders on best practices to maintain healthy bee populations, which are vital for ecosystem services and agricultural productivity.

Natural riparian vegetation as corridors to promote bee diversity and pollination services in an urban landscape

Abstract Understanding how landscape structure and riparian vegetation impact bee diversity is important for maintaining pollination service in urban areas. We explored spatial and temporal variation of bee communities across land use types in a riparian zone of a mountainous megacity in 2018 and 2022, examined whether riparian vegetation functions as corridors that maintain gene flow of bee populations, and mapped pollination supply at the landscape scale. Pielou index was higher in 2018 than in 2022, while no significant differences in abundance, Shannon and richness index were observed. The abundance of bees and the Shannon index were significantly and positively correlated with the abundance of flowers on grassland and forested land, respectively, while both were negatively correlated with the area of the building. The genetic differentiation of the bee communities in the riparian zone was lower than those outside, indicating the function of the riparian vegetation corridor. The pollination supply varied significantly between regions, with medium to high degree of pollination supply distributed primarily in residual habitats and the surrounding urban green spaces, while low degree in the remaining areas. Our results stress the importance of maintaining the continuity of vegetation in riparian zones and increasing flower abundance, especially native plant species, for the conservation of bees in urban areas. Read the free Plain Language Summary for this article on the Journal blog.

Distribution of honey bee mitochondrial DNA haplotypes in an Italian region where a legislative act is protecting the Apis mellifera ligustica subspecies

The conservation of the genetic integrity of Apis mellifera subspecies has emerged as an important objective. In 2019, the Emilia-Romagna region became the first Italian regional authority to issue a law specifically addressing the protection of the native Apis mellifera ligustica subspecies. In this study we analysed a highly informative portion of the mitochondrial DNA (mtDNA), widely used for assessing genetic diversity of honey bee populations. By analysing 1143 honey bees sampled after the introduction of this law, we provided a snapshot of the distribution of mtDNA haplotypes in this region. The two most frequent mtDNA haplotypes were C1 (characteristic of A. m. ligustica) and C2 (characteristic of A. m. carnica), reported in 86.5% and 11.0% of the analysed bees, respectively. About 1.3% and 1.1% of the analysed bees carried mtDNA haplotypes of the A and M lineages (haplotypes A1a, A1e, A4, A26, A65 and two novel ones, A2w and A6a; M3, M3a, M4 and M79). Continued genetic monitoring will be important to assess the impact of this regional law over the coming years. Based on the obtained results, we recommend a more stringent policy to prevent the erosion of the genetic integrity of the native subspecies A. m. ligustica.