A Colorimetric RT-LAMP Assay for Rapid Detection of Soybean mosaic Virus SC15

Soybean mosaic virus (SMV) represents one of the most devastating viral diseases affecting soybeans worldwide. Among its strains, SMV-SC15 is notable for its virulence, predominance, and widespread occurrence. Rapid and on-site diagnosis is important for controlling the spread of SMV-SC15. In this study, we proposed a colorimetric reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of SMV-SC15 using three color indicators for visual interpretation: Neutral Red (N-Red), Bromothymol Blue (BTB), and SYBR Green I. The SMV-SC15 in the soybean tissue was detected with remarkable sensitivity and specificity within 30 min, achieving a detection limit as low as 10^-4 ng/μL. 200 soybean leaf samples from the field were analyzed by the colorimetric RT-LAMP assays, holding significant potential for rapid screening of SMV-SC15-resistant cultivars, thereby contributing to effective SMV control.