Abstract
A new isolate of Sweet potato feathery mottle virus (SPFMV) was obtained from Ipomoea batatas in Oita Prefecture in Japan. The symptoms of I. nil infected with this new isolate differed from those of plants infected with the severe (S), ordinary (O), or Tokushima (T) strains of SPFMV. In addition, reverse transcriptase-polymerase chain reaction-restriction fragment length polymorphism (RT-PCR-RFLP) analysis revealed that this isolate was distinct from these other three strains of SPFMV. The coat protein (CP) of this isolate is composed of 313 amino acids, which have over 90% homology with those in the CPs of SPFMV common strain (C), SPFMV-CH2, SPFMV6 and SPFMV-SOR. On the basis of a phylogenetic analysis of the amino acid sequences of the CP, the isolate was classified as a group C strain, among other strains of SPFMV isolated from sweet potato in other parts of the world. This is the first report on the detection of the SPFMV-C strain in Japan, and we have named this isolate SPFMV-Bungo.
