title: Rapid and specific detection of Yam mosaic virus by reverse-transcription recombinase polymerase amplification.
abstract: Yam mosaic virus (YMV; genus Potyvirus) is considered to cause the most economically important viral disease of yams (Dioscorea spp.) in West Africa which is the dominant region for yam production globally. Yams are a vegetatively propagated crop and the use of virus-free planting material forms an essential component of disease control. Current serological and PCR-based diagnostic methods for YMV are time consuming involving a succession of target detection steps. In this study, a novel assay for specific YMV detection is described that is based on isothermal reverse transcription-recombinase polymerase amplification (RT-exoRPA). This test has been shown to be reproducible and able to detect as little as 14 pg/μl of purified RNA obtained from an YMV-infected plant, a sensitivity equivalent to that obtained with the reverse transcription-polymerase chain reaction (RT-PCR) in current general use. The RT-exoRPA assay has, however, several advantages over the RT-PCR; positive samples can be detected in less than 30 min, and amplification only requires a single incubation temperature (optimum 37°C). These features make the RT-exoRPA assay a promising candidate for adapting into a field test format to be used by yam breeding programmes or certification laboratories.
authors.affiliation: Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK. Electronic address: g.silva@gre.ac.uk.
authors.forename: Gonçalo
authors.initials: G
authors.lastname: Silva
authors.affiliation: Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK.
authors.forename: Moritz
authors.initials: M
authors.lastname: Bömer
authors.affiliation: International Institute of Tropical Agriculture (IITA), Oyo Road, PMB 5320, Ibadan, Nigeria.
authors.forename: Chukwuemeka
authors.initials: C
authors.lastname: Nkere
authors.affiliation: International Institute of Tropical Agriculture (IITA), Oyo Road, PMB 5320, Ibadan, Nigeria.
authors.forename: P Lava
authors.initials: PL
authors.lastname: Kumar
authors.affiliation: Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK.
authors.forename: Susan E
authors.initials: SE
authors.lastname: Seal
mesh_terms: D000354:Africa, Western; D027742:Dioscorea / Q000821:virology*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D010935:Plant Diseases / Q000821:virology*; D017800:Potyvirus / Q000302:isolation & purification*; D045522:Recombinases / Q000378:metabolism; D015203:Reproducibility of Results; D048348:Reverse Transcription; D012680:Sensitivity and Specificity; D013696:Temperature; D013997:Time Factors
chemical_list: D045522:Recombinases
keywords: Diagnosis; Dioscorea spp.; Recombinase polymerase amplification; Yam; Yam mosaic virus