Abstract

In commercial papaya plantations of the southeastern Mexican States of Chiapas, Tabasco, Oaxaca and Veracruz, 0.1 to 10% incidence of plants with peculiar symptoms were observed, sampled and studied for viral infections. Stem internodes were shorter than normal, the leaves were smaller and harder. There was necrosis in younger leaves, petioles were shorter and curved with reddish-gray stripes, and flower and small fruits were standing upright. In negative staining bullet-shaped particles were observed, as well as rod shaped and isometric ones. Bacilliform particles with a perinuclear membrane were also observed within the nucleus in ultra thin preparations, and stained preparations inclusions were present in the nucleus of the floem. The disease could not be mechanically nor seed transmitted. The incidence was higher in the summer than in the winter. All the description coincided with an infection by the papaya apical necrosis Rhabdovirus, although mixed with the papaya ringspot Potyvirus and with an isometric particle not identified.