Abstract:
Rice yellow mottle virus (RYMV) belongs
to the Sobemovirus group and causes the only
known virus disease of rice (Oryza sativa L.) peculiar
to the African continent to date. It was first recorded
in Kenya in 1966 and was not reported in
Tanzania until in the 1980s. It has spread fast and is
found in almost all the rice growing areas. Clearly,
it is the most important disease of rice in Tanzania.
RYMV is transmitted mechanically and by
chrysomelid beetles. Chaetocnema pulla Chapuis is
thought to be an important vector of the disease in
Tanzania. Transmission studies conducted revealed
a new species, Chaetocnema sp. nov. prope
varicornis Jacoby, found in Tanzania as also a vector
of RYMV. This species has not been previously
reported to occur and to vector RYMV in any of the
countries where the disease is prevalent. Further
studies on the roles of these vectors and the dynamics
of virus spread are necessary to provide more
information on the epidemiology of this disease in
Tanzania.
