Establishment and Application of a Rapid Fluorescence-Based RT-LAMP Assay Targeting the CP Gene for Cherry Virus A Detection

In order to establish a rapid and sensitive LAMP visual detection method for Cherry Virus A on-site, this study used the conserved fragment of the CVA coat protein (CP) sequence as a template for primer design. The rapid visual LAMP detection method for Cherry Virus A was successfully established by optimizing the reaction system components (concentration ratio of internal and external primers, and concentrations of loop primers, Bst DNA, Mg2+, dNTPs and betaine) and reaction conditions (temperature and time). This method enables specific detection of Cherry Virus A and facilitates visual inspection of crude nucleic acid extracts within 40 min, significantly reducing the diagnostic turnaround time. The limit of detection is 67.54 pg μL−1 (cDNA), which is 100 times more sensitive than PCR. Analysis of 70 field sweet cherry samples revealed an RT-LAMP positivity rate of 91.42%, significantly surpassing the 71.42% achieved by RT-PCR. This method is suitable for the rapid on-site detection of Cherry Virus, and can also provide a theoretical reference for the early diagnosis of cherry viral diseases.