Establishment of a Serology- and Molecular-Combined Detection System for Youcai Mosaic Virus and Its Application in Various Host Plants

The youcai mosaic virus (YoMV) can infect a diverse array of crop species, such as Raphanus sativus, Brassica napus, Solanum nigrum, and Rehmannia glutinosa, causing substantial economic damage. This study aimed to develop a rapid, sensitive, and economical diagnostic method for YoMV. We successfully expressed and purified the recombinant His-CPYoMV-YZ protein in E. coli BL21, which was used to immunize New Zealand White rabbits, generating high-titer polyclonal antibodies (PAb-CPYoMV-YZ). Additionally, a serological-based reverse transcription loop-mediated isothermal amplification (S-RT-LAMP) assay was refined, combining serological and molecular detection techniques to enhance practicality. Utilizing PAb-CPYoMV-YZ, we developed four techniques for detecting YoMV: Western blot, dot immunoblotting assay, enzyme-linked immunosorbent assay (ELISA), and S-RT-LAMP. YoMV isolates from various regions and hosts were analyzed. The results indicated that PAb-CPYoMV-YZ was highly effective in detecting YoMV across a range of hosts and isolates from diverse regions. This study fills an important gap in the serological detection of YoMV and provides a practical tool for on-site diagnosis and control of YoMV infection.