Data_Sheet_1_Accumulation and Competition Amongst Deformed Wing Virus Genotypes in Naïve Australian Honeybees Provides Insight Into the Increasing Global Prevalence of Genotype B.pdf

Honeybee colony deaths are often attributed to the ectoparasitic mite Varroa destructor and deformed wing virus (DWV), vectored by the mite. In the presence of V. destructor both main genotypes (DWV-A and DWV-B) have been correlated with colony loss. Studies show that DWV-B is the most prevalent genotype in the United Kingdom and Europe. More recently DWV-B has increased in prevalence in the United States. The increasing prevalence of DWV-B at the expense of DWV-A suggests that competition exists between the genotypes. Competition may be due to disparities in virulence between genotypes, differences in fitness, such as rate of replication, or a combination of factors. In this study we investigated if DWV genotypes differ in their rate of accumulation in Australian honeybees naïve to both V. destructor and DWV, and if viral load was associated with mortality in honeybee pupae. We singly and co-infected pupae with DWV-A, DWV-B, and a recombinant strain isolated from a V. destructor tolerant bee population. We monitored viral accumulation throughout pupation, up to 192 h post-injection. We found significant differences in accumulation, where DWV-A accumulated to significantly lower loads than DWV-B and the DWV-recombinant. We also found evidence of competition, where DWV-B loads were significantly reduced in the presence of DWV-A, but still accumulated to the highest loads overall. In contrast to previous studies, we found significant differences in virulence between pupae injected with DWV-A and DWV-B. The average mortality associated with DWV-B (0.4% ± 0.33 SE) and DWV-recombinant (2.2% ± 0.83 SE) injection were significantly less than observed for DWV-A (11% ± 1.2 SE). Our results suggest that a higher proportion of DWV-B infected pupae will emerge into adults, compared to DWV-A. Overall, our data suggest that low mortality in pupae and the ability of DWV-B to accumulate to higher loads relative to DWV-A even during co-infection may favor vector transmission by V. destructor, and may thus be contributing factors to the increasing prevalence of DWV-B globally.</p

Deformed wing virus genotypes A and B do not elicit immunologically different responses in naïve honey bee hosts

Supplementary data files and raw small RNA read

Additional file 1: of Parent-of-origin effects on genome-wide DNA methylation in the Cape honey bee (Apis mellifera capensis) may be confounded by allele-specific methylation

Figure S1. Comparison of fold coverage at methylated CG sites in thelytokous and fertilized embryos. Both samples exhibit a median coverage of 5 reads, thus our comparison of differential methylation was restricted to CG sites with at least 5 reads in both samples. Figure S2. Direct sequencing of bisulfite PCR products of Stoned B (GB17165) from colony 2 and 3 fertilized and thelytokous embryos. Red ovals indicated methylated cytosines, blue squares indicate SNPs. Figure S3. Direct sequencing of bisulfite PCR products of Sap30 (GB18386) from colony 2 and 3 fertilized and thelytokous embryos. Red ovals indicate methylated cytosines, open circles indicate total number of CG sites in the region, and dashed lines indicate incomplete sequence reads. Also shown is the methylation patterns in fertilized and thelytokous embryos from whole genome bisulfite sequencing of Colony 1. Asterisk indicates CG sites that are hypermethylated in fertilized embryos, dagger indicates CG sites hypermethylated in thelyokous embryos. Table S1. Non-CG methylation in Fertilised and Thelytokous embryos and comparison to Apis mellifera Capensis SNPs. Table S2. Primers used in bisulfite nested PCRs of Stan (Fig. 6), Stoned B (Additional file 1: Figure S2), Sap30 (Additional file 1: Figure S3, Syd and Pcl. (PPTX 607 kb

Table_1_Males Are Capable of Long-Distance Dispersal in a Social Bee.xlsx

Pollinator conservation is aided by knowledge of dispersal behavior, which shapes gene flow and population structure. In many bees, dispersal is thought to be male-biased, and males’ movements may be critical to maintaining gene flow in disturbed and fragmented habitats. Yet male bee movements are challenging to track directly and male dispersal ability remains poorly understood in most species. Here, we combine field manipulations and models to assess male dispersal ability in a stingless bee (Tetragonula carbonaria). We placed colonies with virgin queens at varying distances apart (1–48 km), genotyped the males that gathered at mating aggregations outside each colony, and used pairwise sibship assignment to determine the distribution of likely brothers across aggregations. We then compared simulations of male dispersal to our observed distributions and found best-fit models when males dispersed an average of 2–3 km (>2-fold female flight ranges), and maximum of 20 km (30-fold female flight ranges). Our data supports the view that male bee dispersal can facilitate gene flow over long-distances, and thus play a key role in bee populations’ resilience to habitat loss and fragmentation. In addition, we show that the number of families contributing to male aggregations can be used to estimate local stingless bee colony densities, allowing population monitoring of these important tropical pollinators.</p

Data_Sheet_1_Males Are Capable of Long-Distance Dispersal in a Social Bee.pdf

Pollinator conservation is aided by knowledge of dispersal behavior, which shapes gene flow and population structure. In many bees, dispersal is thought to be male-biased, and males’ movements may be critical to maintaining gene flow in disturbed and fragmented habitats. Yet male bee movements are challenging to track directly and male dispersal ability remains poorly understood in most species. Here, we combine field manipulations and models to assess male dispersal ability in a stingless bee (Tetragonula carbonaria). We placed colonies with virgin queens at varying distances apart (1–48 km), genotyped the males that gathered at mating aggregations outside each colony, and used pairwise sibship assignment to determine the distribution of likely brothers across aggregations. We then compared simulations of male dispersal to our observed distributions and found best-fit models when males dispersed an average of 2–3 km (>2-fold female flight ranges), and maximum of 20 km (30-fold female flight ranges). Our data supports the view that male bee dispersal can facilitate gene flow over long-distances, and thus play a key role in bee populations’ resilience to habitat loss and fragmentation. In addition, we show that the number of families contributing to male aggregations can be used to estimate local stingless bee colony densities, allowing population monitoring of these important tropical pollinators.</p

Additional file 3 of Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

Additional file 3

Additional file 5 of Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

Additional file 5

Additional file 1 of Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

Additional file 1

Additional file 6 of Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

Additional file 6

Additional file 4 of Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera

Additional file 4