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Ward, C. M.

Publications and source records attributed to Ward, C. M..

2 recordsLinked to original sources

ngsReports: An R Package for managing FastQC reports and other NGS related log files.

MotivationHigh throughput next generation sequencing (NGS) has become exceedingly cheap facilitating studies to be undertaken containing large sample numbers. Quality control (QC) is an essential stage during analytic pipelines and can be found in the outputs of popular bioinformatics tools such as FastQC and Picard. Although these tools provide considerable power when carrying out QC, large sample numbers can make identification of systemic bias a challenge.\n\nResultsWe present ngsReports, an R package designed for the management and visualization of NGS reports from within an R environment. The available methods allow direct import into R of FastQC output as well as that from aligners such as HISAT2, STAR and Bowtie2. Visualization can be carried out across many samples using heatmaps rendered using ggplot2 and plotly. Moreover, these can be displayed in an interactive shiny app or a HTML report. We also provide methods to assess observed GC content in an organism dependent manner for both transcriptomic and genomic datasets. Importantly, hierarchical clustering can be carried out on heatmaps with large sample sizes to quickly identify outliers and batch effects.\n\nAvailability and ImplementationngsReports is available at https://github.com/UofABioinformaticsHub/ngsReports.

bioinformatics

A global Brassica pest and a sympatric cryptic ally, Plutella australiana (Lepidoptera: Plutellidae), show strong divergence despite the capacity to hybridize

The diamondback moth, Plutella xylostella, has been intensively studied due to its ability to evolve insecticide resistance and status as the worlds most destructive pest of brassicaceous crops. The surprise discovery of a cryptic ally, Plutella australiana Landry & Hebert, with apparent endemism to Australia, immediately raised questions regarding the extent of ecological and genetic diversity between these two species, whether gene flow could occur, and ultimately if specific management was required. Here, we show that despite sympatric distributions and the capacity to hybridize in controlled laboratory experiments, striking differences in genetic and phenotypic traits exist that are consistent with contrasting colonization histories and reproductive isolation after secondary contact. Almost 1500 Plutella individuals were collected from wild and cultivated brassicaceous plants at 75 locations throughout Australia. Plutella australiana was commonly found on all Brassica host types sampled except commercial vegetables, which are routinely sprayed with insecticide. Bioassays using four commonly-used insecticides found that P. australiana was 19-306 fold more susceptible than P. xylostella. Genome-wide SNPs derived from RADseq revealed substantially higher levels of genetic diversity across P. australiana compared with P. xylostella nuclear genomes, yet both species showed limited variation in mtDNA. Infection with a single Wolbachia subgroup B strain was fixed in P. australiana, suggesting that a selective sweep contributed to low mtDNA diversity, while a subgroup A strain infected just 1.5 % of P. xylostella. Although P. australiana is a potential pest of brassica crops, it is of secondary importance to P. xylostella.

genetics