An isolate of ryegrass mosaic virus (RMV-SA) was found in Italian ryeg
rass plants in two areas in South Africa. Preliminary characterization
indicated that the virus exhibited the same symptoms and host range a
s RMV strains previously found in Canada and the UK. The virus was tra
nsmitted by the eriophyid mite Abacarus hystrix. Particle structure an
d size were comparable to the USA and UK strains. The coat protein and
RNA were found to be slightly larger than previously reported, being
32 kDa and 2.8 x 10(6), respectively. The virus exhibited serological
cross-reactivity with antisera to RMV-Wales and RMV-Canada but was not
serologically related to other Rymovirus members.