ABSTRACT
The family was originally erected around reovirus, which infects man and other mammals and whose name was derived from the description "respiratory enteric orphan virus"; "orphan" because at the time no disease had been found associated with the particles. The viruses in this genus possess particles that are morphologically indistinguishable and all genomes consist of 10 double-stranded RNA segments of similar sizes. The plant Reoviridae so far studied all contain double-stranded RNA inside icosahedrally constructed protein shells whose diameter has variously been measured as between 45 and 59 nm. Rice dwarf (RDV) differs from all the other plant Reoviridae in not inducing cell hyperplasia. RDV-infected plants are stunted and develop chlorotic patches, like Gramineae infected by a wide variety of viruses. Mature particles are seen in the cytoplasm outside the viroplasms. The tubules are found only in the cytoplasm, may contain rows of mature virus particles, and may be incompletely closed, forming scrolls.
