Biology subjects

Dill-Macky, R.

Publications and source records attributed to Dill-Macky, R..

2 recordsLinked to original sources

bioRxiv2022

Development of genome-driven, lifestyle-informed primers for identification of the cereal infecting pathogens Xanthomonas translucens pathovars undulosa and translucens.

Bacterial leaf streak, blight and black chaff caused by Xanthomonas translucens pathovars are major diseases affecting small grains. Xanthomonas translucens pv. translucens and X. translucens pv. undulosa are seedborne pathogens that cause similar symptoms on barley, but only X. translucens pv. undulosa causes bacterial leaf streak of wheat. Recent outbreaks of X. translucens have been a concern for wheat and barley growers in the Northern Great Plains and Upper Midwest; however, there are limited diagnostic tools for pathovar differentiation. We developed a multiplex PCR based on whole-genome differences to distinguish X. translucens pv. translucens and X. translucens pv. undulosa. We validated the primers across different Xanthomonas and non-Xanthomonas strains. To our knowledge, these are the first multiplex PCR to distinguish X. translucens pv. translucens and X. translucens pv. undulosa. These molecular tools will support disease management strategies enabling detection and pathovar incidence analysis of X. translucens.

microbiology↗

bioRxiv2022

Comparative genomics of Minnesotan barley-infecting Xanthomonas translucens shows overall genomic similarity but virulence factor diversity

Xanthomonas translucens pv. translucens (Xtt) is a global barley pathogen and a concern for resistance breeding and regulation. Long-read whole genome sequences allow in-depth understanding of pathogen diversity. We have completed long-read PacBio sequencing of two Minnesotan Xtt strains and an in-depth analysis of available Xtt genomes. We found that average nucleotide identity(ANI)-based approaches organize Xtt strains differently than the previously standard MLSA approach. According to ANI, Xtt forms a separate clade from Xanthomonas translucens pv. undulosa and consists of three main groups which are represented on multiple continents. The global distribution of Xtt groups suggests that regulation of seed is not important for prevention of Xtt spread. Some virulence factors, such as 17 Type III-secreted effectors, are highly conserved and offer potential targets for the elicitation of broad resistance. However, there is a high degree of variation in virulence factors meaning that germplasm should be screened for resistance with a diverse panel of Xtt.

genomics↗