VIEW ARTICLE

Etiology

Host Plant Reactions, Some Properties, and Serology of Wild Potato Mosaic Virus. R. A. C. Jones, International Potato Center, Apartado 5969, Lima, Peru; C. E. Fribourg, Departamento de Sanidad Vegetal, Universidad Nacional Agraria, Apartado 456, Lima, Perú. Phytopathology 69:446-449. Accepted for publication 26 October 1978. Copyright 1979 The American Phytopathological Society. DOI: 10.1094/Phyto-69-446.

A virus for which the name wild potato mosaic virus (WPMV) is proposed was isolated from plants of the wild potato species Solanum chancayense growing in the lomas vegetation in the Peruvian coastal desert; infected plants showed symptoms of severe mosaic and leaf deformation. The host range of WPMV was, restricted to certain species in five solanaceous genera. Nicotiana bigelovii, N. clevelandii, and N. occidentalis were useful indicator hosts, and N. rustica reacted with local lesions. The virus infected systemically seven of 16 wild, tuber-forming, Solanum spp. including S. chancayense and S. mochicense. However, none of the 13 potato cultivars tested became infected. The virus was readily transmitted after acquisition periods of 30 sec or 1 min by the aphid Myzus persicae. Nicotiana clevelandii leaf sap remained infective when diluted to 10^–3 but not to 10^–4, when heated at 60 C but not at 65 C, and when stored for 5 but not 6 days. Electron microscopy of infective sap revealed long flexuous particles about 735 nm in length, typical of the potato virus Y (potyvirus) group. In microprecipitin grid titration tests, antiserum to WPMV reacted with partially purified antigens of eight different potyviruses from solanaceous hosts, and antisera to three of these reacted with WPMV in reciprocal tests. The virus was most closely related serologically to Peru tomato virus, tobacco vein mottling virus and to potato virus Y. However, differences in its host range and symptomatology clearly distinguished WPMV from these three viruses.