Double-stranded RNA in Carica papaya is not associated with dieback disease and is unlikely to be of viral origin

Abstract

Two distinct double-stranded RNA (dsRNA) patterns, each comprising two major bands, were detected in extracts from apparently healthy Carica papaya plants. The slowest migrating band was present in both patterns and had an estimated Mr of 2.8 x 106 . The faster migrating bands had estimated Mrs 1.3 x 106 or 1.2x106. When papaw total and organellar DNA was extracted and hybridized with 32P-end labelled papaw dsRNA, the probe hybridized strongly with total and chloroplast DNA, but only very weakly with mitochondria1 and nuclear DNA.