Virus Infections of Vanilla and Other Orchids in French Polynesia. G. C. Wisler, Biological Scientist III, Florida Department of Agriculture and Consumer Services, Division of Plant Industry, Bureau of Plant Pathology, Gainesville 32602. F. W. Zettler, and L. Mu. Professor, Department of Plant Pathology, University of Florida, Gainesville 32611; and Plant Pathologist, Ministére de l'Agriculture, Recherche Agronomique, Papeete, Tahiti, French Polynesia. Plant Dis. 71:1125-1129. Accepted for publication 29 April 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-1125.

Four of 663 Vanilla tahitensis samples collected from Moorea, Raiatea, Tahaa, and Tahiti, French Polynesia, and assayed serologically had either cymbidium mosaic (CyMV) or odontoglossum ringspot (ORSV) virus. Neither virus was found in any of the 51 wild plants of the terrestrial native orchid, Spathoglottis plicata, growing in or near Vanilla plantations in French Polynesia. Much higher amounts of infection were noted in ornamental orchids; 40% of 74 samples had CyMV and 20% had ORSV. Four of the nine experimental Vanilla hybrids assayed tested positively for CyMV. A mosaic-inducing virus distinct from CyMV and ORSV was detected in V. tahitensis plantations in Huahine, Raiatea, Tahaa, and Tahiti but not in Moorea. The virus was determined to be a potyvirus with a mean particle length of 767 nm, was transmitted in a styletborne manner by aphids, induced cylindrical inclusions, and was serologically related to other potyviruses.

Keyword(s): Arachnis, bean yellow mosaic virus, Cattleya, clover yellow vein virus, dasheen mosaic virus, Dendrobium, Myzus persicae, sodium dodecyl sulfate immunodiffusion serology, subdivision III potyviruses, Vanda, Vanilla fragrans, V. planifolia.