Disease Note.

Occurrence of Cymbidium Mosaic Virus and Odontoglossum Ring-spot Virus in Korea. Ki Hyun Ryu, Won Mok Park, Department of Agricultural Biology, College of Natural Resources, Korea University, Seoul 136-701.. So Young Chung and Kyung Eun Yoon, Department of Horticultural Science, College of Natural Science, Seoul Woman's University, Seoul 132-240, Korea. Plant Dis. 79:321. Accepted for publication 24 January 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0321D.

Several commercial orchid nurseries in Korea propagate orchids by tissue culture. Orchid hobbyists in Korea frequently collect cool-growing orchids like Cymbidium sinense Willd., C. kanran M., C. ensifolium Sw., and C. goeringii Rchb., and some grow Calanthe, Paphiopedilum, and Vanda spp. This survey was conducted to determine the incidence and distribution of viruses in cultivated orchids in Korea Samples were assayed by enzyme-linked immunosorbent assay and immunosorbent electron microscopy. Cymbidium mosaic (CyMV) and odontoglossum ring-spot (ORSV) viruses were detected in 16 and 100 of 186 orchid samples, respectively. Ten samples were doubly infected. ORSV was detected nationwide, and incidences of it varied from 79.3% in Chungnam to 24.0% in Cheju. CyMV was detected in the 3 Provinces but not Cheju. The occurrence of the viruses most likely resulted from infection with (he viruses of mother plants used for vegetative propagation. This survey shows that the incidence of virus disease in cultivated orchids is more severe than in native ones (1). ORSV is more prevalent than CyMV in Korea; this condition is rare in other countries (2).