Virus Diseases of Pepper in Northeast Oregon. P. B. Hamm, Department of Botany and Plant Pathology, Oregon State University, P.O. Box 105, Hermiston 97383 . J. R. Jaeger, Department of Botany and Plant Pathology, Oregon State University, P.O. Box 105, Hermiston 97383, and L. MacDonald, B.C. Ministry of Agriculture, Fisheries & Food, 17720-57 Avenue, Surrey, B.C. Canada, V3S 4P9. Plant Dis. 79:968. Accepted for publication 31 July 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0968A.
Bell pepper (Capsicum anuum L.) for processing and the fresh market, has been grown for 4 years as a new crop in Umatilla County of northeast Oregon. At least three symptom types, considered viral in origin, have been characterized from a field in which the crop was considered a complete loss. Two of the symptom types were readily distinguished, and confirmed by enzyme-linked immunosorbent assay (ELISA) as beet curly top virus (BCTV symptoms of stunting, chlorosis, and mortality) and alfalfa mosaic virus (AMV small to large irregular mottling on leaves and fruit) infected plants of the two symptom types were found in low incidence throughout the field or concentrated near an adjoining alfalfa field, respectively. The third symptom type, a mild foliar mottle and slight distortion and stunting, was not as pronounced, and was found throughout the field. Fruit on infected plants were streaked or mottled with areas of lighter green, and were sometimes distorted. A rod-shaped viruslike particle, approximately 300 nm long, was found in electron microscope leaf dips from affected plants. Symptoms and particle size pointed to pepper mild mottle virus (PMMV) this was confirmed by serology with polyclonal PMMV antiserum (from R. Stace-Smith), and greenhouse mechanical transmission to pepper (1). In recent years, BCTV and AMV have always been found in pepper in northeast Oregon, but PMMV has only been found one year. This is the first report of AMV and PMMV on pepper in Oregon. All three viruses could cause serious losses to pepper in this region in the future.Reference: (1) C. Welter el al. Phytopathology 74:405, 1984.