Characterization of a pothos (Scindapsus aureus) virus with unusual properties

A virus for which the name of pothos latent virus (PoLV) is proposed, was isolated by inoculation of sap from symptomless plants ofScindapsus aureus. PoLV had isometric particlesc. 30 nm in diameter, a monopartite genome consisting of a non polyadenylated, single-stranded RNA moleculec. 4,300 nucleotides in length, constitutingc. 17% of the particle weight, and a single type of coat protein subunit with aM _r ofc. 40,000 Daltons. The biological properties (host range reactions) of PoLV resembled those ofTombusviridae for it infected most of the artificial hosts locally, inducing symptoms recalling those elicited by several species of the above family. Like tombus- and carmoviruses, PoLV had two subgenomic RNAs which, however, differed in size from those of both genera. The dsRNA pattern was also distinctly different. Cytopathological features recalled those of tombusviruses except for the lack of multivesicular inclusion bodies. PoLV was serologically related to, but distinct from twoCarmovirus (i.e., galinsoga mosaic and Ahlum waterborne viruses) and threeTombusvirus species (i.e. eggplant mottled crinkle, Sikte waterborne and Lato river viruses). Thus, PoLV had properties somewhat intermediate between those ofTombusvirus andCarmovirus genera but bridged the two taxa through the serological relationship with some of their species. The taxonomic position of PoLV is still undetermined. It must await the results of molecular investigations now underway.     

Detection and identification of Clerodendron golden mosaic China virus in Salvia splendens

Two viral DNAs were obtained by rolling circle amplification conducted on DNA extracts from salvia (Salvia splendens) cv. ‘Dancing Flame’ showing variegated foliage resembling virus symptoms. Sequence analyses revealed the presence of an isolate of the putative begomovirus Clerodendron golden mosaic China virus. The virus was detected in all salvia plants showing variegated foliage, but not in non-variegated plants. The virus was graft-transmitted to healthy salvias which reproduced the original symptoms. Attempts to transmit the virus with the whitefly Bemisia tabaci biotype B failed. The results of this investigation strongly suggest that the salvia isolate of Clerodendron golden mosaic China virus (ClGMCNV-Sal[USA:LA:11]) is the cause of the variegated foliage of S. splendens cv. ‘Dancing Flame’. This is the first report of this virus in the United States.