Link to home

Differentiation Among Potyviruses Infecting Sweet Potato Based on Genus-and Virus-Specific Reverse Transcription Polymerase Chain Reaction

February 1998 , Volume 82 , Number  2
Pages  223 - 229

D. Colinet , M. Nguyen , J. Kummert , and P. Lepoivre , Faculté Universitaire des Sciences Agronomiques, Unité de Phytopathologie, 13 Avenue Maréchal Juin, 5030 Gembloux, Belgium , and Feng Zu Xia , Upland Crops Research Institute, Guangzhou, China

Go to article:
Accepted for publication 4 November 1997.

Knowledge of virus diseases affecting sweet potato has been complicated due to the frequent occurrence of mixed infections and difficulties in isolating and purifying sweet potato viruses. A combined assay of reverse transcription and polymerase chain reaction (PCR) utilizing degenerate genus-specific primers POT1 and POT2 was applied to 18 sweet potato clones from China. The primers were designed to amplify the variable 5′ terminal region of the potyvirus coat protein gene. Molecular analysis of the amplified fragments identified the Chinese strains of sweet potato feathery mottle virus (SPFMV-CH), sweet potato latent virus (SPLV-CH), and sweet potato virus G (SPVG-CH). Among the detected potyviruses, a distantly related strain of SPFMV-CH, tentatively named SPFMV-CH2, was identified in sweet potatoes from China. On the basis of sequence identity, SPFMV-CH2 was closely related to the common (-C) strain of that virus. Identification of a closely related strain of SPVG-CH in one sweet potato clone from China further illustrated the usefulness of broad-spectrum PCR for detecting uncharacterized viruses. The acquisition of sequence information permitted the design of virus-specific primers for detecting and differentiating SPFMV, SPLV, and SPVG.

© 1998 The American Phytopathological Society