scholarly journals Comparative transcriptomics indicates endogenous differences in detoxification capacity after formic acid treatment between honey bees and varroa mites

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Antonia Genath ◽  
Soroush Sharbati ◽  
Benjamin Buer ◽  
Ralf Nauen ◽  
Ralf Einspanier

AbstractFormic acid (FA) has been used for decades to control Varroa destructor, one of the most important parasites of the western honey bee, Apis mellifera. The rather unselective molecular mode of action of FA and its possible effects on honeybees have long been a concern of beekeepers, as it has undesirable side effects that affect the health of bee colonies. This study focuses on short-term transcriptomic changes as analysed by RNAseq in both larval and adult honey bees and in mites after FA treatment under applied conditions. Our study aims to identify those genes in honey bees and varroa mites differentially expressed upon a typical FA hive exposure scenario. Five detoxification-related genes were identified with significantly enhanced and one gene with significantly decreased expression under FA exposure. Regulated genes in our test setting included members of various cytochrome P450 subfamilies, a flavin-dependent monooxygenase and a cytosolic 10-formyltetrahydrofolate dehydrogenase (FDH), known to be involved in formate metabolism in mammals. We were able to detect differences in the regulation of detoxification-associated genes between mites and honey bees as well as between the two different developmental stages of the honey bee. Additionally, we detected repressed regulation of Varroa genes involved in cellular respiration, suggesting mitochondrial dysfunction and supporting the current view on the mode of action of FA—inhibition of oxidative phosphorylation. This study shows distinct cellular effects induced by FA on the global transcriptome of both host and parasite in comparison. Our expression data might help to identify possible differences in the affected metabolic pathways and thus make a first contribution to elucidate the mode of detoxification of FA.

Insects ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1032
Author(s):  
Ziyad Abdul Qadir ◽  
Atif Idrees ◽  
Rashid Mahmood ◽  
Ghulam Sarwar ◽  
Muhammad Abu Bakar ◽  
...  

Honey bees (Apis mellifera) are essential for their products—honey, royal jelly, pollen, propolis and beeswax. They are also indispensable because they support ecosystems with their pollination services. However, the production and functions of honey bees are hindered by the arthropod pest Varroa destructor, which attacks bees through its feeding activities. Efforts to control varroa mites have been made through the development of various synthetic pesticide groups, but have had limited success because the mites developed resistance and some of these pesticides are harmful to bees. Branded pesticides are rarely used in Pakistan, as beekeepers utilize acaricides from unknown sources. There is a need to create awareness of available naturally occurring acaricides that may serve as an alternative to synthetic acaricides. Although some naturally occurring compounds are considered toxic to the environment, the soft acaricides oxalic acid, thymol, and formic acid 65% are usually safe for honey bee colonies and beekeepers, when handled appropriately. The current study investigated the effectiveness of formic acid (10, 15, and 20 mL/hive), oxalic acid (4.2, 3.2, and 2.1%/hive), and thymol (6, 4, and 2 g/hive) in controlling mite infestation. The results indicated that all treatments significantly reduced the mite population (p < 0.05). The average efficacies of oxalic acid at 3.2% (94.84% ± 0.34) and 4.2% (92.68% ± 0.37) were significantly higher than those of the other treatments. The lowest efficacy was recorded in formic acid 65% at 10 mL (54.13%). Overall, the results indicated that soft acaricides—such as oxalic acid at 3.2% and 4.2% concentrations—are very effective at controlling varroa mites and can be used in broodless conditions without side effects.


Author(s):  
Deborah A. Kuterbach

Foraging honey bees are believed to use the earth's magnetic field, among other cues, in order to home. It has been reported that the abdomen of the honey bee contains magnetite and iron particles have been localized within abdominal oenocytes. Light microscopic investigations reveal that morphologically detectable iron granules are present only in adult animals older than six days after eclosion (emergence from the comb). This is a report of an ultrastructural examination of the oenocytes during the development of the worker honey bee (Apis mellifera) with particular emphasis on the time of appearance, number, and size of iron granules within the cells.Specimens of the different developmental stages were removed from brood comb, fixed in 2.5% glutaraldehyde in 5mM sodium cacodylate buffer pH 7.3, washed, and post-fixed with 1% osmium tetroxide. In order to preserve the lipid-rich material, rapid dehydration was accomplished by three changes of 50% acetone and two changes of 100% acetone before embedding in Polybed 812 epoxy resin.


2018 ◽  
Vol 62 (1) ◽  
pp. 141-144 ◽  
Author(s):  
Mayra C. García-Anaya ◽  
Alejandro Romo-Chacón ◽  
Alma I. Sáenz-Mendoza ◽  
Gerardo Pérez-Ordoñez ◽  
Carlos H. Acosta-Muñiz

Abstract The recent alarming loss of honey bee colonies around the world is believed to be related to the presence of viruses. The aim of this study was to detect two major viral diseases, Apis mellifera Filamentous virus (AmFV) and Israeli Acute Paralysis Virus (IAPV) using Reverse Transcription - Polymerase Chain Reaction RT-PCR, in honey bees in Mexico. Adult and larvae honey bee samples were collected from asymptomatic colonies of six major beekeeping regions in the state of Chihuahua, Mexico. Both viruses were detected in both developmental stages of honey bees, IAPV at a higher prevalence (23.5%) as compared to AmFV, only in 0.9% of samples. However, this is the first report on AmFV infection in Mexican apiaries. Further studies are required to understand the AmFV and IAPV impact on colony loss in Mexico and to develop strategies for enhancing the control of viral diseases.


2006 ◽  
Vol 32 (2) ◽  
pp. 115-124 ◽  
Author(s):  
James W. Amrine ◽  
Robert Noel
Keyword(s):  

2007 ◽  
Vol 139 (6) ◽  
pp. 881-893 ◽  
Author(s):  
Robyn M. Underwood ◽  
Robert W. Currie

AbstractThis study examined the effects of indoor fumigation with formic acid on survival of honey bee, Apis mellifera L. (Hymenoptera: Apidae), queens and varroa mites (Varroa destructor Anderson and Trueman (Acari: Varroidae)). A relationship between cumulative formic acid concentration and varroa mite mortality was established for colonies subjected to high-concentration fumigation while held indoors at 2–4 °C during winter. We also examined the effects of the formic acid release pattern and room ventilation rate on queen loss and treatment efficacy during fumigation. Two experiments were conducted in a wintering building. In both experiments, room air had higher formic acid concentrations than hive air. In experiment 1, 50% and 95% of mites were killed when exposed to in-hive concentration × time combinations of 49 ppm × days (CT50 product) and 111 ppm × days (CT95 product), respectively. No queen loss was observed under either the increasing-concentration or constant high concentration fumigation pattern. In experiment 2, 33% of queens were lost when minimum ventilation was used with room air concentrations of 57 ± 8 ppm (mean ± SE), whereas no queens were lost in controls or colonies exposed to room air concentrations of 27 ± 8 ppm with variable ventilation. Queen loss was associated with peak in-hive formic acid concentrations >20 ppm, but not with CT product, suggesting that queens are affected by acute rather than chronic exposure to formic acid. Formic acid fumigation significantly reduced the mean abundance of mites under both minimum- and variable-ventilation treatments.


Viruses ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 890
Author(s):  
Severine Matthijs ◽  
Valérie De Waele ◽  
Valerie Vandenberge ◽  
Bénédicte Verhoeven ◽  
Jacqueline Evers ◽  
...  

The health of honey bees is threatened by multiple factors, including viruses and parasites. We screened 557 honey bee (Apis mellifera) colonies from 155 beekeepers distributed all over Belgium to determine the prevalence of seven widespread viruses and two parasites (Varroa sp. and Nosema sp.). Deformed wing virus B (DWV-B), black queen cell virus (BQCV), and sacbrood virus (SBV) were highly prevalent and detected by real-time RT-PCR in more than 95% of the colonies. Acute bee paralysis virus (ABPV), chronic bee paralysis virus (CBPV) and deformed wing virus A (DWV-A) were prevalent to a lower extent (between 18 and 29%). Most viruses were only present at low or moderate viral loads. Nevertheless, about 50% of the colonies harbored at least one virus at high viral load (>107 genome copies/bee). Varroa mites and Nosema sp. were found in 81.5% and 59.7% of the honey bee colonies, respectively, and all Nosema were identified as Nosema ceranae by real time PCR. Interestingly, we found a significant correlation between the number of Varroa mites and DWV-B viral load. To determine the combined effect of these and other factors on honey bee health in Belgium, a follow up of colonies over multiple years is necessary.


Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 566
Author(s):  
Gyan P. Harwood ◽  
Adam G. Dolezal

Honey bees are key agricultural pollinators, but beekeepers continually suffer high annual colony losses owing to a number of environmental stressors, including inadequate nutrition, pressures from parasites and pathogens, and exposure to a wide variety of pesticides. In this review, we examine how two such stressors, pesticides and viruses, may interact in additive or synergistic ways to affect honey bee health. Despite what appears to be a straightforward comparison, there is a dearth of studies examining this issue likely owing to the complexity of such interactions. Such complexities include the wide array of pesticide chemical classes with different modes of actions, the coupling of many bee viruses with ectoparasitic Varroa mites, and the intricate social structure of honey bee colonies. Together, these issues pose a challenge to researchers examining the effects pesticide-virus interactions at both the individual and colony level.


Sign in / Sign up

Export Citation Format

Share Document