title: A rapid isothermal assay for the detection of Hop stunt viroid in hop plants (Humulus lupulus), and its application in disease surveys.
abstract: Hop stunt disease caused by Hop stunt viroid (HSVd) is a growing threat to hop cultivation globally. HSVd spreads mainly by use of contaminated planting material and by mechanical means. Thorough testing of hop yards and removal of infected bines are critical components of efforts to control the spread of the disease. Reverse transcription-polymerase chain reaction (RT-PCR) has become the primary technique used for HSVd detection; however, sample handling and analysis are technically challenging. In this study, a robust reverse transcription-recombinase polymerase amplification (RT-RPA) assay was developed to facilitate analysis of multiple samples. The assay was optimized with all major variants of HSVd from other host species in addition to hop variants. Used in conjunction with sample collection cards, RT-RPA accommodates large sample numbers. Greenhouse and farm samples tested with RT-RPA were also tested with RT-PCR and a 100% correlation between the two techniques was found.
authors.affiliation: Department of Plant Pathology, Washington State University, IAREC, 24106 North Bunn Road, Prosser, WA 99350, USA. Electronic address: madhu.kappagantu@wsu.edu.
authors.forename: Madhu
authors.initials: M
authors.lastname: Kappagantu
authors.affiliation: Department of Plant Pathology, Washington State University, IAREC, 24106 North Bunn Road, Prosser, WA 99350, USA.
authors.forename: Dan Edward V
authors.initials: DEV
authors.lastname: Villamor
authors.affiliation: Department of Plant Pathology, Washington State University, IAREC, 24106 North Bunn Road, Prosser, WA 99350, USA.
authors.forename: Jeff M
authors.initials: JM
authors.lastname: Bullock
authors.affiliation: Department of Plant Pathology, Washington State University, IAREC, 24106 North Bunn Road, Prosser, WA 99350, USA.
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Eastwell
mesh_terms: D002957:Citrus / Q000821:virology; D004279:DNA, Viral; D016679:Genome, Viral; D027582:Humulus / Q000821:virology*; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D013696:Temperature; D014772:Viroids / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004279:DNA, Viral
keywords: FTA sample cards; Hop stunt viroid; Humulus lupulus; Isothermal amplification; Reverse transcription-recombinase polymerase amplification assay