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Simple Summary: Deformed wing virus (DWV) is the most widespread bee virus and one of the most destructive pathogens affecting honeybees. Initially believed to be a honeybee virus with one dominant variant, DWV-A, we now know there are four master variants DWV-A, B (VDV-1), C and D. Since 2010, a shift in prevalence from the originally dominant DWV-A strain towards an increase in DWV-B prevalence has been observed in several countries. The geographical isolation of the bee populations in Hawaii provides a unique opportunity to examine the changes in DWV strain prevalence both at the individual colony and the apiary level. In this study, we present longitudinal data on the prevalence of DWV strains in individual colonies on the Island of Oahu, Hawaii. We found that although DWV-A was the dominant strain in the apiary, individual colonies could now be characterized as a mix of DWV-A and DWV-B and some tested positive for DWV-B only. Finally, DWV-B exhibited seasonal variations in both viral loads and prevalence in the apiary. Our long term DWV monitoring at the individual colony level contributes a unique perspective on the emerging patterns of DWV-B. The most prevalent viral pathogen of honeybees is Deformed Wing Virus (DWV) and its two most widely studied and common master-variants are DWV-A and DWV-B. The prevalence of DWV variants in the UK and in the US is changing, with the prevalence of the DWV-A strain declining and DWV-B increasing over time. In 2012, only DWV-A was detected on the Hawaiian Islands of Oahu. In this study we focused on a colony-level survey of DWV strains in a single apiary and examined the prevalence of DWV variants over the course of two years. In 2018 and 2019, a total of 16 colonies underwent viral testing in January, May, and September. Of those 16 colonies, four were monitored in both 2018 and 2019. Individual colonies showed variability of DWV master variants throughout the sampling period. DWV-A was consistently detected; however, the detection of DWV-B was variable across time in individual colonies. Ultimately, this study demonstrated a seasonal variation in both viral prevalence and load for DWV-B, providing a perspective on the dynamic nature of DWV master variants emerging in Hawaii. [ABSTRACT FROM AUTHOR]

An association between host plant chemistry and the mating success of male medflies mediated, at least in part, through plant-induced variation in male pheromone calling is reported. Results reveal that male medflies exposed to particular sections of guava bark, entire trees containing such stations, or guava fruits gained a mating advantage over males without such exposure.

Varroa destructor , a parasitic mite of honey bees, is also a vector for viral diseases. The mite displays high host specificity and requires access to colonies of Apis spp . to complete its lifecycle. In contrast, the Deformed Wing Virus (DWV), one of the many viruses transmitted by V. destructor , appears to have a much broader host range. Previous studies have detected DWV in a variety of insect groups that are not directly parasitized by the mite. In this study, we take advantage of the discrete distribution of the Varroa mite in the Hawaiian archipelago to compare DWV prevalence on non- Apis flower visitors, and test whether Varroa presence is linked to a “viral spillover”. We selected two islands with different viral landscapes: Oahu, where V. destructor has been present since 2007, and Maui, where the mite is absent. We sampled individuals of Apis mellifera , Ceratina smaragdula , Polistes aurifer , and Polistes exclamens , to assess and compare the DWV prevalence in the Hymenoptera community of the two islands. The results indicated that, as expected, honey bee colonies on Oahu have much higher incidence of DWV compared to Maui. Correspondingly, DWV was detected on the Non- Apis Hymenoptera collected from Oahu, but was absent in the species examined on Maui. The study sites selected shared a similar geography, climate, and insect fauna, but differed in the presence of the Varroa mite, suggesting an indirect, but significant, increase on DWV prevalence in the Hymenoptera community on mite-infected islands. [ABSTRACT FROM AUTHOR]

Deals with a study which investigated the effects of diet, ginger root oil, and elevation on the mating competitiveness of male Mediterranean fruit flies (Diptera: Tephritidae) from a mass-reared, genetic sexing strain in Guatemala. Background to the study; Materials and methods; Results; Discussion.

The combination of Deformed wing virus (DWV) and Varroa destructor is arguably one of the greatest threats currently facing western honey bees, Apis mellifera. Varroa's association with DWV has decreased viral diversity and increased loads of DWV within honey bee populations. Nowhere has this been better studied than in Hawaii, where the arrival of Varroa progressively led to the dominance of the single master variant (DWV-A) on both mite-infested Hawaiian Islands of Oahu and Big Island. Now, exactly 10 years following the original study, we find that the DWV population has changed once again, with variants containing the RdRp coding sequence pertaining to the master variant B beginning to co-dominate alongside variants with the DWV-A RdRp sequence on the mite-infested islands of Oahu and Big Island. In speculation, based on other studies, it appears this could represent a stage in the journey towards the complete dominance of DWV-B, a variant that appears better adapted to be transmitted within honey bee colonies. [ABSTRACT FROM AUTHOR]

The high annual losses of managed honey bees (Apis mellifera) has attracted intensive attention, and scientists have dedicated much effort trying to identify the stresses affecting bees. There are, however, no simple answers; rather, research suggests multifactorial effects. Several works have been reported highlighting the relationship between bees' immunosuppression and the effects of malnutrition, parasites, pathogens, agrochemical and beekeeping pesticides exposure, forage dearth and cold stress. Here we analyze a possible connection between immunity-related signaling pathways that could be involved in the response to the stress resulted from Varroa-virus association and cold stress during winter. The analysis was made understanding the honey bee as a superorganism, where individuals are integrated and interacting within the colony, going from social to individual immune responses. We propose the term "Precision Nutrition" as a way to think and study bees' nutrition in the search for key molecules which would be able to strengthen colonies' responses to any or all of those stresses combined. [ABSTRACT FROM AUTHOR]