VIEW ARTICLE

Etiology

Host Plant Reactions, Some Properties, and Serology of Peru Tomato Virus. C. E. Fribourg, Departamento de Sanidad Vegetal, Universidad Nacional Agraria, Apartado 456, Lima, Perú; Phytopathology 69:441-445. Accepted for publication 26 October 1978. Copyright 1979 The American Phytopathological Society. DOI: 10.1094/Phyto-69-441.

Peru tomato virus (PTV) is common in tomato crops in the coastal valleys of central Peru. Symptoms in diseased plants are mottle, epinasty, leaf crinkling, and systemic necrotic spotting. The weeds Nicandra physaloides, Physalis peruviana, and Solanum nigrum are natural hosts. The host range is restricted to species of the Solanaceae and Chenopodiaceae. Lycopersicon pimpinellifolium, Nicotiana occidentalis, N. glutinosa, and Chenopodium amaranticolor were useful indicator species. Peru tomato virus infected 11 tomato cultivars and the wild tomato species L. pimpinellifolium, L. chilense, and L. peruvianum. The virus was transmitted following acquisition periods of 30 sec by the aphid Myzus persicae, but was not transmitted through seed to tomato or N. physaloides. Nicotiana occidentalis sap remained infective when diluted to 10^–4 but not 10^–5, when heated for 10 min at 50 C but not at 55 C, and when stored for 4 but not 5 days. Electron microscopy of infective sap showed long flexuous particles about 775 nm in length which were typical of the potyvirus group. Seven different potyviruses that infect solanaceous hosts were all serologically related to PTV. Of these, potato virus Y (PVY) and tobacco vein-mottling virus (TVMV) were most closely related. However, differences in its host range and symptomatology clearly distinguished PTV from these two, supporting its designation as a distinct virus.