A novel technology for the one-step detection of prune dwarf virus: Colorimetric reverse transcription loop-mediated isothermal amplification assay

A one-step colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed to target the coat protein region of genomic RNA of prune dwarf virus (PDV). WarmStart 2X Master Mix from NEB (New England Biolabs) was used for naked eye observation of positive LAMP reactions, where the changing in color from pink to yellowish indicates a positive result. The detection sensitivity of the new technique was 10-fold higher than that of conventional PCR. The assay's specificity was evaluated against the nucleic acids of potential hosts of PDV, prunus necrotic ringspot virus (PNRSV), and apple mosaic virus (ApMV) from the Ilarvirus genus. The novel RT-LAMP test showed high sensitivity in distinguishing PDV and genome of potential hosts and other Ilarvirus genus members. The RT-LAMP test was proven to be reliable for diagnosis of PDV in infected sweet cherry samples from the field. The specific, sensitive, and quick RT-LAMP test described in this study can be used in laboratories and for PDV surveillance in the field. To best of our knowledge, this is the first report of RT-LAMP detection for PDV.