ABSTRACT
The Nodaviridae are a family of small, isometric insect-pathogenic riboviruses, each possessing a bipartite messenger sense genome encapsidated within a single virion. This family represents the simplest class of multipartite viruses. The only other known bipartite viruses are those of plants; these, however, have their genome parts encapsidated in separate virions. Unenveloped icosahedral insect-pathogenic viruses of about 30 nm diameter, having a bipartite single-stranded RNA genome encapsidated in a single virion, are defined as nodaviruses. Very little is known regarding the epidemiology of nodaviruses, as each virus was obtained after a single isolation from insects collected in one locality. Only in the case of FHV has the natural distribution of the virus been examined. Prior to the development of suitable tissue culture systems, nodaviruses had to be propagated in whole organisms. The first investigations of nodaviral genetics were attempts to make hybrid viruses by transfecting Drosophila cells with mixtures of RNAs obtained from different nodaviruses.
