Median lethal dose (LD₅₀) of acaricides to honey bees in 2009 following sublethal treatment with acaricides, fungicides, or detoxicative enzyme inhibitors.

<p>Confidence intervals (95%) are indicated below the LD₅₀ values. Significant differences compared to the control treatment are indicated with a superscript letter: a = significant pre-treatment effect, b = significant pre-treatment*acaricide dose effect (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054092#pone.0054092.s001" target="_blank">Table S1</a>). LD₅₀ values taken from previous work: † = <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054092#pone.0054092-Johnson3" target="_blank">[35]</a>, ‡ = <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054092#pone.0054092-Johnson1" target="_blank">[22]</a>. Names for classical enzyme inhibitors are abbreviated as follows DEM = diethyl maleate, DEF = S,S,S-tributylphosphorotrithioate, PBO = piperonyl butoxide. A dash “−” indicates an LD₅₀ that could not be calculated because of insufficient data.</p

Median lethal doses (LD₅₀) for tau-fluvalinate in honey bees pre-treated with piperonyl butoxide (PBO) or a sterol biosynthesis inhibiting (SBI) fungicide at three dose levels.

<p> Significant differences compared to the control treatment are indicated with a superscript letter a = significant pre-treatment effect, b = significant pre-treatment*acaricide dose effect (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054092#pone.0054092.s003" target="_blank">Table S3</a>).</p

Plot of log-transformed dose and probit-transformed honey bee mortality data for tau-fluvalinate toxicity after oxalic acid or control pre-treatments.

<p>Symbols represent raw mortality and solid lines indicate lines fitted using the full model. Dotted lines represent 95% confidence intervals for each line fit with the full model. Dashed green lines were fitted using the same slope for both pre-treatments. The dashed blue line was fitted with combined data from both pre-treatments. Likelihood ratio tests comparing the full model and the reduced models were used to determine pre-treatment effects and pre-treatment * dose effects.</p

Acaricide, Fungicide and Drug Interactions in Honey Bees (<em>Apis mellifera</em>)

<div><h3>Background</h3><p>Chemical analysis shows that honey bees (<em>Apis mellifera</em>) and hive products contain many pesticides derived from various sources. The most abundant pesticides are acaricides applied by beekeepers to control <em>Varroa destructor</em>. Beekeepers also apply antimicrobial drugs to control bacterial and microsporidial diseases. Fungicides may enter the hive when applied to nearby flowering crops. Acaricides, antimicrobial drugs and fungicides are not highly toxic to bees alone, but in combination there is potential for heightened toxicity due to interactive effects.</p> <h3>Methodology/Principal Findings</h3><p>Laboratory bioassays based on mortality rates in adult worker bees demonstrated interactive effects among acaricides, as well as between acaricides and antimicrobial drugs and between acaricides and fungicides. Toxicity of the acaricide tau-fluvalinate increased in combination with other acaricides and most other compounds tested (15 of 17) while amitraz toxicity was mostly unchanged (1 of 15). The sterol biosynthesis inhibiting (SBI) fungicide prochloraz elevated the toxicity of the acaricides tau-fluvalinate, coumaphos and fenpyroximate, likely through inhibition of detoxicative cytochrome P450 monooxygenase activity. Four other SBI fungicides increased the toxicity of tau-fluvalinate in a dose-dependent manner, although possible evidence of P450 induction was observed at the lowest fungicide doses. Non-transitive interactions between some acaricides were observed. Sublethal amitraz pre-treatment increased the toxicity of the three P450-detoxified acaricides, but amitraz toxicity was not changed by sublethal treatment with the same three acaricides. A two-fold change in the toxicity of tau-fluvalinate was observed between years, suggesting a possible change in the genetic composition of the bees tested.</p> <h3>Conclusions/Significance</h3><p>Interactions with acaricides in honey bees are similar to drug interactions in other animals in that P450-mediated detoxication appears to play an important role. Evidence of non-transivity, year-to-year variation and induction of detoxication enzymes indicates that pesticide interactions in bees may be as complex as drug interactions in mammals.</p> </div

Median lethal doses (LD₅₀) of acaricides to honey bees in 2010 fed antimicrobial drugs used in beekeeping.

<p>Confidence intervals (95%) are indicated below the LD₅₀ values. Significant differences compared to the respective treatment are indicated with a superscript letter a = significant pre-treatment effect, b = significant pre-treatment*acaricide dose effect (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0054092#pone.0054092.s002" target="_blank">Table S2</a>).</p

Toxicity of pesticides to <i>Apis mellifera</i> in the presence and absence of P450 inducers.

<p>Toxicity bioassays for the pyrethroid pesticides tau-fluvalinate and lambda-cyhalothrin, the organochlorine aldrin, and its bioactivated P450 metabolite dieldrin, using 3-day-old bees fed sucrose “bee candy” or candy with phenobarbital (5 mg/g candy), xanthotoxin (1 mg/g), quercetin (10 mg/g), salicylic acid (2.5 mg/g) or indole-3-carbinol (1 mg/g) added. N = total number of bees included in bioassay, LD₅₀ = Lethal Dose 50%, as calculated by probit model, 95%CI = 95% confidence interval for the LD₅₀ (treatments with non-overlapping 95% confidence intervals are considered significantly different) , slope = slope of the log-probit line, intercept = intercept of the log-probit line, SE = standard error, chi square = statistical test for the probit model, if significant then correction for heterogeneity using Fieller's method was applied, df = degrees of freedom for the chi square test.</p

<i>Apis mellifera</i> CYP6AS family P450s and their gene expression following feeding on honey, pollen or propolis extract.

<p>Expression of selected P450 genes, as measured by northern blot, in guts of bees fed five g candy containing only sucrose or sucrose plus extract from the given quantity of honey, pollen or propolis. The neighbor-joining tree is rooted with <i>Homo sapiens</i> CYP3A4 and was created using CLUSTALW <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031051#pone.0031051-Thompson1" target="_blank">[88]</a> alignment and PHYLIP <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031051#pone.0031051-Felsenstein1" target="_blank">[89]</a> with 1000 bootstrap replicates. Branches with greater than 50% bootstrap support are indicated with an asterisk. Branch length in the final tree was corrected for multiple substitutions with TREE-PUZZLE <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031051#pone.0031051-Schmidt1" target="_blank">[90]</a>.</p

Median survival times for <i>Apis mellifera</i> fed various diets with and without aflatoxin B1 (AB1).

<p>Aflatoxin B1 was applied at 20 µg/g candy in 0.1% dimethyl sulfoxide (DMSO). A DMSO control was applied to diets of pure sucrose “bee candy”, or candy made from equal parts honey and sucrose or high fructose corn syrup (HFCS) and sucrose.</p

Draft genome assembly for the parsnip webworm Depressaria pastinacella

Genomic DNA from adult Depressaria pastinacella (parsnip webworm) moth was extracted. The W.M. Keck Center for Comparative and Functional Genomics at the University of Illinois at Urbana-Champaign generated the following libraries for sequencing: 180-bp and 1-kb insert shotgun libraries from a single male moth and 5-kb, 10-kb and 20-kb insert mate-pair libraries. The 180-bp and 1-kb insert shotgun libraries were prepared with Illumina's TruSeq DNAseq Sample Prep Kit. The 5-kb mate-pair library was prepared similarly except a custom linker was ligated between the read-ends to facilitate mate-pair recovery. The 10- and 20-kb insert mate-pair libraries were prepared with Illumina’s Nextera Mate-Pairs Sample Prep Kit. All libraries were sequenced for 100 cycles on a HiSeq2000 using the TruSeq SBS Sequencing Kit v.3. Data were analyzed with pipeline version 1.8. The custom 5-kb and Nextera 10-kb and 20-kb mate-pair libraries were filtered for reads containing properly-oriented reads of the appropriate insert size and uniqueness. Raw Illumina reads were trimmed at the 5’ and 3’ ends for nucleotide-bias and low-quality bases using the FASTX Toolkit (http://hannonlab.cshl.edu/fastx_toolkit/). Trimmed reads were error-corrected by Quake counting 19-mers. SOAPdenovo v2.04 (Luo et al. 2012), was employed with K=49 to assemble the 180-bp insert library reads followed by scaffolding with iteratively longer insert mate-pair libraries and use of GapCloser v1.12 (Luo et al. 2012) to close gaps generated in the scaffolding process

Genbank-derived ITS2 reference library

This is a reference library of 2628 plant ribosomal sequences downloaded from Genbank on March 11, 2014. This library represents approximately half of the 4918 plant species potentially present in Ohio and surrounding states (USDA PLANTS database; http://plants.usda.gov/). This file is in FASTA format