Strains of soybean mosaic virus in Kyusyu

Molecular characterization of A2 and D strains of Soybean mosaic virus, which caused a recent virus outbreak in soybean cultivar Sachiyutaka in Chugoku and Shikoku regions of Japan

“…Two isolates (Ka3 and To3) of strain A 2 had high sequence similarity to No. 8010, which was isolated from a soybean plant in Kumamoto Prefecture two decades ago (Nakano et al 1982). This indicates that Sachiyutaka may have been infected with SMV strain A 2 in Kumamoto Prefecture before the cultivar was introduced to Chugoku and Shikoku districts.…”

“…Soybean mosaic disease, caused by Soybean mosaic virus (SMV) in the genus Potyvirus, is probably the most common soybean virus and one of the biggest problems for soybean growers in Japan (Nakano et al 1982;Takahashi et al 1980). Many SMV strains have been reported around the world (Chen et al 2004;Cho and Goodman 1979;Takahashi et al 1980).…”

“…Based on the phenotypic reactions of differential soybean cultivars, seven distinct virulence strains, G1-G7, were identified among 98 isolates in the U.S. soybean germplasm collection (Cho and Goodman 1979). In Japan, Takahashi et al (1980) grouped 102 isolates into five strains, A-E, and Nakano et al (1982) later divided SMV strain A into two strains, A 1 and A 2 .…”

“…Sachiyutaka by mechanical inoculation. To assess their biological significance, the seven isolates were used to inoculate a series of soybean differential cultivars developed by Takahashi et al (1980) and Nakano et al (1982). Eight plants of each cultivar were inoculated with each isolate at the primary leaf stage and maintained in insect-proof cages at 18°-25°C.…”

“…These amplified and Stu, stunt a Phenotypic reactions of six SMV strains were described by Takahashi et al (1980) and Nakano et al (1982) PCR fragments were separated by electrophoresis in 1% agarose gel and isolated from the gel using a QIAquick gel extraction kit (Qiagen, Hilden, Germany). Purified PCR fragments were directly ligated into plasmid pGEM-T Easy Vector (Promega, Madison, WI, USA).…”