Development of a lateral-flow assay (LFA) for rapid detection of Soybean mosaic virus

Soybean mosaic virus (SMV) is the most common virus in soybean and poses a serious threat to crop production and germplasm recession in many countries worldwide. In this study, a highly practical and rapid lateral-flow assay (LFA) was developed for the detection of SMV. The SMV coat protein (CP) was prokaryotically expressed and purified to immunize mice. After generation of hybridoma cell lines, four anti-SMV monoclonal antibodies were selected. The LFA-strip was then assembled using a double-antibody sandwich strategy. When the SMV-infected leaf sample was assayed using the assembled LFA-strip, the positive pink color appeared in the test line within 5-10min. The strip only gave positive results with SMV and not other viruses tested and could be used to detect 800 fold dilutions of infected leaf samples. The LFA could be used to detect SMV in infected leaf tissue as well as soybean seeds. To our knowledge, this is the first report of the development of a LFA for the detection of SMV. The practical, rapid and specific assay that was developed in this study can be widely applied to the diagnosis and surveillance of SMV in the laboratory and the field.