Characterization of a Small RNA-Containing Virus in Field-Collected Larvae of the Tussock Moth, Lymantria ninayi, from Papua New Guinea

Field-collected larvae of the tussock moth, Lymantria ninayi, a major pest of exotic pines in Papua New Guinea, were found to contain a small RNA-containing virus with a diameter of 29 nm and a buoyant density of 1.32 g/ml. The RNA was single stranded, had a molecular weight of 2.8 × 10⁶, and was polyadenylated. Virion RNA stimulated an in vitro translation system, and high-molecular-weight proteins were produced. Purified virions contained four structural proteins with molecular weights of 43,000, 38,000, 33,000, and 32,000. The virus reacted positively with antisera raised against a strain of Drosophila C virus. The properties of this virus indicate that it should be placed in the family Picornaviridae.