Host Range and Serology of Prunus Necrotic Ringspot Virus Serotypes Isolated from Hops (Humulus lupulus) in Washington. D. R. Smith, Research Technologist III, Irrigated Agriculture Research and Extension Center, Prosser, WA 99350. C. B. Skotland, Plant Pathologist, Irrigated Agriculture Research and Extension Center, Prosser, WA 99350. Plant Dis. 70:1019-1023. Accepted for publication 9 June 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-1019.

Prunus necrotic ringspot virus serotypes NRSV-HP-1 (HP-1) and NRSV-HP-2 (HP-2) were isolated from hops (Humulus lupulus). Although both viruses produced chlorotic line pattern and ringspot on hops, they could be distinguished by their host range and by serology. Based on mini-double-immunodiffusion tests, HP-1 showed some serological similarity to Fulton’s CAMV but was serologically distinct from Fulton’s NRSV-G. HP-2 showed partial serological similarity to NRSV-G, HP-1, and CAMV. In enzyme-linked immunosorbent assay (ELISA), antisera prepared against HP-1 and CAMV reacted strongly with both antigens and less strongly with HP-2. Neither detected NRSV-G antigens. Antiserum against HP-2 reacted strongly with homologous antigen and less strongly with both HP-1 and CAMV antigens. Antiserum against NRSV-G reacted with homologous antigen and very slightly with HP-2. HP-2 appeared to be serologically intermediate between NRSV-G and CAMV.