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bioRxiv · 10.1101/2025.02.28.640647

Xanthomonas citri pv. lagerstroemium, description of a new pathovar causing leaf spot on crape myrtle

Moura Duin, I.·Ritchie, D.·Braswell, E.·Fagen, J.
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Abstract

Bacterial leaf spot caused by Xanthomonas was reported in 2014 as a new disease of crape myrtle. Unfortunately, this foundational strain was lost, preventing further experimentation, sequencing of the genome, and phylogenetic analysis. This work describes a collection of Xanthomonas strains isolated from angular leaf spot lesions on crape myrtle in North Carolina from 2014 to 2023. This study includes full reference genomes, as well as re-fulfillment of Kochs postulates. Genomes were obtained with hybrid whole genome sequencing using Illumina and Nanopore and assembled to develop robust genomic resources for these disease-causing strains. The completed genomes support inclusion of the strains in the X. citri species group; however, both phylogenetic analysis and the identification of a novel plant host suggest the creation of the new pathovar Xanthomonas citri pv. lagerstroemium.

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Moura Duin, I., Ritchie, D., Braswell, E., Fagen, J.. 2025-03-01. Xanthomonas citri pv. lagerstroemium, description of a new pathovar causing leaf spot on crape myrtle. https://doi.org/10.1101/2025.02.28.640647

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