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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » National Germplasm Resources Laboratory » Research » Publications at this Location » Publication #403044
Research Project: Characterization and Detection of Viruses that Impact the Exchange and Curation of Plant Germplasm

Location: National Germplasm Resources Laboratory

Title: Targeting the highly conserved 3' untranslated region of Iris Severe Mosaic Virus for sensitive monitoring of the disease prevalanece in Iris production

Author
item GRUNWALD, DERRICK - University Of Wisconsin
item STROSCHEIN, SYDNEY - University Of Wisconsin
item Grinstead, Sam
item Mollov, Dimitre
item RIOUX, RENEE - University Of Wisconsin
item RAKOTONDAFARA, AURELIE - University Of Wisconsin

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/27/2023
Publication Date: 11/28/2023
Citation: Grunwald, D., Stroschein, S., Grinstead, S.C., Mollov, D.S., Rioux, R., Rakotondafara, A. 2023. Targeting the highly conserved 3' untranslated region of Iris Severe Mosaic Virus for sensitive monitoring of the disease prevalanece in Iris production. Plant Disease. https://doi.org/10.1094/PDIS-04-23-0631-RE.
DOI: https://doi.org/10.1094/PDIS-04-23-0631-RE

Interpretive Summary: Iris, which is both the genus and common name, is a flowering perennial widely used in the ornamental industry. Plant pathogens, including viruses reduce the marketability of the crop. In this study we obtained the genomic sequence of iris severe mosaic virus (ISMV) isolates from Wisconsin and designed a sensitive PCR test to detect this pathogen. The diagnostic test is specific for ISMV and can selectively detect it, but not other viruses infecting iris or viruses related to ISMV. This research will help regulatory agencies enable certification programs to ensure the movement and sale of clean stock, and help the ornamental industry reduce virus infections in the crop.

Technical Abstract: Iris severe mosaic virus (ISMV, Potyviridae) can threaten the sustainability of iris production and the marketability of the plants. Effective intervention and control strategies require rapid and early detection of viral infections. The wide range of viral symptoms, from asymptomatic to severe chlorosis of the leaves, renders diagnosis solely based on visual indicators ineffective. A nested PCR-based diagnostic assay was developed for the reliable detection of ISMV in iris leaves and in rhizomes. Considering the genetic variability of ISMV, two primer pairs were designed to detect the highly conserved 3’ untranslated region (UTR) of the viral genomic RNA. The specificity of the primer pairs was confirmed against four other potyviruses. The sensitivity of detection was enhanced by two orders of magnitude using diluted cDNA and a nested approach. Nested PCR facilitated detecting ISMV on field-grown samples beyond the capabilities of a currently available immunological test, and in iris rhizome, which would facilitate ensuring clean stock is planted. This approach dramatically improves the detection threshold of ISMV on potentially low virus titer samples. The study provides a practical, accurate, and sensitive tool for the early detection of a deleterious virus that infects a popular ornamental and landscape plant.