Journal of Apicultural Research

The application of treatments to reduce/control the number of Varroa destructor mites within Apis mellifera colonies is a common apicultural practice. The effectiveness of the treatments in reducing Varroa mites from colonies has been extensively studied, however, the effects of these treatments on the bees within the colonies are poorly characterised. This work utilised label-free quantitative proteomic analysis to investigate how the presence of the anti-Varroa treatment amitraz, affected worker bees. Samples of A. mellifera were isolated from colonies one week before amitraz treatment (T0) and 1, 3, 6 and 8 weeks post-treatment application. The trial was conducted during the transition period from short-lived summer workers to long-lived winter workers. The results highlight two large proteomic shifts; a decrease in the abundance of cuticular proteins and an increase in ribosomal protein abundance in Weeks 3, 6, and 8. The changes in the protein abundance in Week 8 may not be a response to amitraz exposure alone but may also be attributed to a potential change in the population of short-lived to long-lived winter bees. The work provides insight into the effect of amitraz on the honey bee proteome during the transition period from summer to winter colony and how it may contribute to inducing a stress response in individual bees.

Queen rearing is a common beekeeping practice that plays a crucial role in modern apiculture. To enhance the efficiency of the queen rearing process, plastic queen cell cups have gained widespread popularity amongst queen producers. However, concerns have arisen regarding the potential adverse effects of these petrochemical-based products on queen rearing success and their development. To address this concern, we compared beeswax cups to 10 different commercial plastic queen cups by evaluating their effects on rearing success, queen development, and physical characteristics. Our results showed that plastic queen cell cups are manufactured in a variety of dimensions (inner diameter, depth, and wall thickness). A comparison of queen rearing between beeswax cups and different plastic cups revealed significant differences in larval acceptance, followed by sealing, and queen emergence. Negative correlations were observed between the inner diameter, the depth of queen cups, and the three metrics of queen rearing: acceptance, sealing, and queen emergence rates. While significant variation was observed among larvae weights raised in different queen cups, the differences were less pronounced for the deposited royal jelly weight measured from beeswax queen cups compared to different plastic cups. The weight and morphometric parameters of queens emerging from beeswax cups were similar to those from different plastic types. It indicates the need for standardizing queen cup dimensions without compromising the physical quality of queens.

The Western honey bee, Apis mellifera (A. mellifera) Linnaeus, is one of the world’s most economically important pollinators. Conserving genetic resources in this species is therefore of significant value. Despite this, little attention has been paid to the potential erosion of locally adapted genetic variants by transhumance of particular subspecies favoured by beekeepers. In particular, introgression and hybridisation by repeated backcrossing can disrupt naturally-selected allele combinations and therefore erode local adaptation. Here we use whole genome sequencing (WGS) to assess levels of introgression in the native subspecies Apis mellifera mellifera (A. m. mellifera) across a wide geographical scale in Britain and Ireland. Samples were obtained from both colonies maintained by individual beekeepers from non-imported stock and those outside of protected populations or specific breeding programmes. These were examined alongside sub-species reference samples from established refuges. ADMIXTURE and ABBA BABA analysis revealed that 17 out of 70 colonies showed no significant introgression. The remaining 53 colonies showed some evidence of introgression. This study underpins previous findings that Ireland harbours a large reservoir of A. m. mellifera. The Island of Colonsay (Scotland) and parts of the South West of England also harbour ‘pure’ colonies. New areas of interest for conservation are identified in Jersey, mainland Scotland and the Isle of Man. Our results are discussed in the context of implications for future research and conservation strategies of this globally important insect in its native range.

As in other organisms, the antioxidant cellular defense system of bees helps maintain homeostasis. However, extrinsic factors such as pesticides and nutritional deficiencies can interfere. To determine whether nutritional supplementation can mitigate the oxidative damage caused by fungicides, five colonies were supplemented with sucrose syrup and a pollensucrose paste for 14 wk, while five other colonies were subjected to reduced protein intake due to the installation of pollen traps at hive entrances and were not given supplementary food. Following the food management period, forager bees were exposed by contact to 1 or 7 mg of a modern three component fungicide, or by its fungicide components, bixafen, prothioconazole, and trifloxystrobin, individually. After 24 h, treated and untreated control bees were dissected, and thorax homogenates were evaluated for signs of oxidative stress. Without fungicide treatment, food supplementation induced higher activity of the enzymatic antioxidants such as glutathione peroxidase and catalase, and altered the reduced glutathione to glutathione disulfide ratio. Increased malondialdehyde was detected in bees exposed to the three fungicides alone or in combination, except for trifloxystrobin at the lower dose, independent of nutritional condition. Food supplementation of honey bee colonies did not mitigate the oxidative stress caused by these fungicides in the bees.

European foulbrood (EFB) is a severe bacterial honey bee brood disease caused by the Grampositive bacterium Melissocccus plutonius. The disease is widely distributed worldwide, and is an increasing problem in some areas. Although the causative agent of EFB was described almost a century ago, many basic aspects of its pathogenesis are still unknown. Earlier studies were hampered by insensitive and unspecific methods such as culture based techniques. Recent advances in molecular technologies have led to a boom in the methods available to study both disease and causative organism, but not all published methods offer data of equal quality, or are likely to result in success. This paper presents selected step-by-step methodologies that have been used with success in at least one laboratory of the authors and considered relevant by the consortium of authors. We hope this paper helps providing some assistance to those wishing to work on M. plutonius and EFB, and speeds up the discovery of new knowledge to improve the control of this damaging and often neglected disease.

The Red dwarf honey bee (Apis florea), is a single-comb open-nesting member of the genus Apis with a natural distribution area stretching from the Indomalayan realm on the east to the Persian Gulf on the west. However, it is reportedly colonising new territories mainly due to anthropogenic activities. Nowadays it can be found from Taiwan on the east, to Jordan, the Arabian Peninsula and North-eastern Africa on the west. Here we present the first scientific record of a fully established colony of A. florea in Europe. The colony was found on Malta, a crossway of naval routes in the Mediterranean Sea. We documented the incident with photos, collected samples of workers and drones and sequenced the mtDNA COI gene to confirm assignment to A. florea. Also, we alert the competent authorities and the beekeeping community to be vigilant and ready to undertake effective eradication measures. In the paper, we discuss the risks and the potential consequences associated with the invasion of A. florea in Europe.

In South America, the movement of stingless bee colonies outside their natural location is a common practice and, in many cases, meliponiculture activities are conducted in urban or semi-urban areas. In this study, we used a temperature/relative humidity probe inside the hives to assess indicators of hive dynamics to explore the adaptation of Scaptotrigona jujuyensis colonies located in an urban park outside the species’ natural range. The temperature inside the hives was negatively correlated with environmental temperature and its range was narrower than in the empty box (control). These results suggest that the colonies regulate the internal temperature and form a microenvironment, with average values ranging between 29 and 21 �C in the brood chamber, and between 27 and 19 �C in the storage chamber. The number of bees involved in the three flight activities studied varied with the time of the day, through the season and colony. Nevertheless, between 10:00 and 15:00 h, all colonies showed high and continuous activity. The pattern of activity curves of S. jujuyensis tends to be similar to other Scaptotrigona. Finally, we fit Generalized Linear Models to assess the effect of abiotic variables on the flight activity of S. jujuyensis through a negative binomial model. Our results show that the temperature of the brood chamber, relative humidity and colony size best predict the collection of pollen and removal pellets into the hive. These results contribute to the management and conservation of this native species in a new scenario of geographic distribution.