Virus-like particles in the plant hopper Javesella pellucida Fab.

Javesella pellucida Fab. (Homoptera, Delphacidae) is one of two plant hoppers known to transmit the pathogen called European wheat striate mosaic virus (EWSMV) (Kisimoto & Watson, 1965) which has not yet been purified or identified visually (Serjeant, 1967). In an attempt to find the pathogen, infective hoppers were sectioned and examined in the electron microscope; ‘healthy’ hoppers, which had had no contact with infected plants, were also examined. In both kinds we found the virus-like particles, apparently unassociated with EWSMV, described below.

Hoppers collected at Sutton Bonington, Nottinghamshire (Ammar, 1969) and those from the Rothamsted stock were maintained on wheat as described by Slykhuis & Watson (1958). Organs from young adult hoppers were removed and fixed in glutaraldehyde, further fixed in osmium tetroxide, dehydrated in acetone, stained in uranyl acetate, embedded in Epon, sectioned and further stained in lead citrate, and examined in a Siemens Elmiskop 1A.