Panel of three loop-mediated isothermal amplification assays differentiates Rathayibacter toxicus populations RT-I, RT-II, RT-III, RT-IV and RT-V

  • Jarred Yasuhara-Bell
  • James P. StackEmail author
Short Communication


Rathayibacter toxicus is a nematode-vectored (Anguina sp.) plant-pathogenic (Poaceae; grasses) bacterium that secretes a toxin, which can cause fatalities in livestock and horses that ingest diseased plant material. The lethal toxicoses associated with R. toxicus are annual ryegrass toxicity and flood plain staggers. Currently, this bacterium is confined to certain areas of Australia and South Africa. Previous studies have shown that populations from Western Australia (RT-III) are genetically distinct from populations from South Australia (RT-II). A recent study discovered a newly emerged population in South Australia (RT-I), distinct from both Western and South Australian populations studied previously. In this study, a six-gene MLST delineated five distinct genetic populations. Phenotypic significance of these different populations is not yet known. A set of molecular-based assays for the specific detection of R. toxicus has been developed. Described here are loop-mediated isothermal amplification (LAMP) assays for rapid identification and differentiation of R. toxicus populations in the field or laboratory. These assays can be used subsequent to an R. toxicus-specific field assay, allowing on-site determination of population type. This will allow informed field sampling to collect populations of interest, as well as track the movement of populations to new areas.


Multiplex LAMP Annual ryegrass toxicity Nematode-vectored pathogen Anguina Detection Population 



The authors would like to acknowledge the support of the Australian Government’s Cooperative Research Centres Program, Canberra, Australia. Contribution no. 19-008-J from the Kansas Agricultural Experiment Station.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Supplementary material

42161_2018_232_MOESM1_ESM.docx (20 kb)
ESM 1 (DOCX 20 kb)


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Copyright information

© Società Italiana di Patologia Vegetale (S.I.Pa.V.) 2019

Authors and Affiliations

  1. 1.Department of Plant PathologyKansas State UniversityManhattanUSA
  2. 2.Biosecurity Research InstitutePat Roberts Hall, Kansas State UniversityManhattanUSA

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