Development of transcription recombinase polymerase based isothermal amplification coupled with lateral flow immunochromatographic assay for visual detection of citrus tatter leaf virus

The citrus tatter leaf virus (CTLV) is one of the most destructive citrus viral diseases worldwide. In this study, reverse transcription-recombinase polymerase amplification combined with a lateral flow dipstick (RT-RPA-LFD) assay for rapid visual detection of CTLV was established. The assay was performed at 35 ℃ in 27 min without specialised equipment. The RT-RPA-LFD assay showed high specificity to CTLV, and the sensitivity to CTLV was the same as that of quantitative RT-PCR at 3 × 103 copies/μL CTLV RNA transcripts. A total of 45 field tangor samples were tested using RT-RPA-LFD, RT-PCR, and RT-qPCR, and the results were consistent. The results demonstrated that the RT-RPA-LFD assay is a promising tool for rapid on-site CTLV detection.