Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/6/1993
Publication Date: N/A
Citation: Interpretive Summary: A new virus, Peanut Top Paralysis Virus, was discovered in Stillwater, OK. Original symptoms on wild peanut were very mild, with a single leaflet stunted at the base in a fanlike appearance. However, when the virus was mechanically transmitted to cultivated peanut, it caused very severe and destructive symptoms, unlike those of any previously reported peanut viruses in the United States. Detailed evaluations were conducted to partially characterize the virus. The discovery of this virus is important from both academic and applied points of view and will be used by peanut researchers and the peanut industry.
Technical Abstract: A destructive virus causing top paralysis to peanut was discovered in the wild germplasm collection of the USDA-ARS, Stillwater, OK. Symptoms observed on the wild plant were restricted to a few leaves as green batches in a light green to yellow background with some leaflets having lost most of the basal part of the laminae, leaving top portion rolling upward forming a cone. The virus was mechanically transmitted to cultivated peanu (Arachis hypogaea L.) where it caused more severe and destructive symptoms including stunting, severe leaf malformation, and partial or complete disappearance of leaflet laminae. This virus differed in symptomology, host range, and/or serological reactivity from all peanut viruses reported in literature, particularly those causing leaf malformation and stunting. The virus induced necrotic local lesions on Phaseolus vulgaris L. cv. 'Topcrop' and chlorotic local lesions with necrotic centers bordered with very bright tintense red color on Chenopodium amaranticolor. In both PAS-ELISA and Ouchterlony double immunodiffusion test, the virus did not react with antisera against brome mosaic, bean yellow mosaic, peanut stripe, potato Y, tobacco mosaic, watermelon mosaic 1, watermelon mosaic 2, wheat soilborne mosaic, wheat streak mosaic, and zucchini yellow mosaic viruses. However, in reciprocal cross reactions the virus seemed to share a common antigenic determinant with a peanut mottle virus isolate from Oklahoma (PMV-OK). The virus had flexuous filamentous particles with a length of 750-850 nm, falling within the range reported for the potyvirus group. The virus was successfully purified and the molecular weight of its protein subunit was found to be 30000 d. A polyclonal antiserum was raised in rabbits against the virus and used for reciprocal serological tests.