Plant Disease (2015) 99, 195-200

Jill E. Demers, Jo Anne Crouch and Lisa A. Castlebury (2015)
A multiplex real-time PCR assay for the detection of Puccinia horiana and P. chrysanthemi on Chrysanthemum
Plant Disease 99 (2), 195-200
Abstract: Puccinia horiana, the cause of chrysanthemum white rust, is a regulated fungal plant pathogen in the United States, while P. chrysanthemi, the cause of chrysanthemum brown rust, is a widespread but less destructive pathogen. Accurate identification is essential to enforce quarantine measures, but the two species cannot be differentiated visually in the absence of mature spores or symptoms. A multiplex real-time PCR assay was developed to detect and discriminate between P. chrysanthemi and P. horiana. Species-specific hydrolysis probes labeled with different fluorescent dyes were designed based on the rDNA internal transcribed spacer region. Seven fresh samples and 270 herbarium specimens of chrysanthemum rust were tested with the assay with results confirmed using spore morphology. P. horiana and P. chrysanthemi were accurately detected from all fresh samples, and as little as 1 pg of template DNA was reproducibly detected. Of the herbarium specimens, 99% were positive for at least one species using the multiplex assay with 7% positive for both species. This multiplex assay can discriminate between P. chrysanthemi and P. horiana and provides an additional tool for identification of P. horiana to ensure appropriate application of quarantine measures.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Lisa A. Castlebury

Research topic(s) for pests/diseases/weeds:
identification/taxonomy
surveys/sampling/distribution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Puccinia horiana	Chrysanthemum (genus)
	Puccinia chrysanthemi	Chrysanthemum (genus)