Submitted to: Journal of Virological Methods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/11/2012
Publication Date: 7/16/2012
Citation: Li, F., Zuo, R., Abad, J., Xu, D., Bao, G., Li, R. 2012. Simultaneous detection and differentiation of four closely related sweet potato potyviruses by a multiplex one-step RT-PCR. Journal of Virological Methods. 186:161-166. Interpretive Summary: Sweet potato is one of most important root/tuber crops in the world. More than 30 different viruses infect and cause diseases on sweet potatoes. Sweet potato viral disease is caused by mixed infections of several viruses, including Sweet potato feathery mottle virus (SPFMV), Sweet potato virus C (SPVC), Sweet potato virus G (SPVG) and Sweet potato virus 2 (SPV2). It is the most devastating viral disease of sweet potatoes worldwide and can reduce the yields up to 80-90%. In this study, a simple, sensitive, and cost-effective molecular method is developed to detect these four viruses in one tube. The assay is reliable using plant samples from both the greenhouse and fields, and should be very useful in quarantine, certification, and virus survey programs.
Technical Abstract: Four closely related potyviruses, Sweet potato feathery mottle virus (SPFMV), Sweet potato virus C (SPVC), Sweet potato virus G (SPVG) and/or Sweet potato virus 2 (SPV2), are involved in Sweet Potato Viral Disease, the most devastating disease of sweet potato worldwide. Identification and detection of these viruses is complicated by high similarity among their genomic sequences, frequent occurrence as mixed infections and low titer in many sweet potato cultivars. A one-tube multiplex reverse transcription – PCR (mRT-PCR) assay was developed for simultaneous detection and differentiation of SPFMV, SPVC, SPVG and SPV2. Four specific forward primers unique to each virus and one reverse primer based on the region conserved in all four viruses were selected and used in the assay. The mRT-PCR assay was optimized for primer concentration and cycling conditions. It was tested using sweet potato plants naturally infected with one to four target viruses and then evaluated using field samples collected from southwestern China. The mRT-PCR assay is reliable and sensitive as a simple, rapid and cost-effective method to detect these pathogens in sweet potato. This assay will be useful to quarantine and certification programs and virus surveys when large numbers of samples are tested