Natural infections of tomato by Citrus exocortis viroid, Columnea latent viroid, Potato spindle tuber viroid and Tomato chlorotic dwarf viroid

Abstract

Since 1988, viroids have been occasionally detected in samples of tomato (Lycopersicon esculentum) originating both in the Netherlands and other countries. Infected plants showed chlorosis, bronzing, leaf distortion and growth reduction. Initial diagnosis of these viroids was by return-polyacrylamide gel electrophoresis, which did not allow a further identification. This paper reports the identification of these viroids by reverse transcription-polymerase chain reaction and sequence analysis. Three known viroids of tomato, i.e. Citrus exocortis viroid; Potato spindle tuber viroid and Tomato chlorotic dwarf viroid were identified. In addition, six isolates were identified as Columnea latent viroid, a viroid so far only detected in some ornamental species. Like the isolates previously isolated from ornamental species, the isolates from tomato share genetic characteristics of both the genera Hostuviroid and Pospiviroid. The biological characteristics of all four viroids, especially their potential effects on both potato (Solanum tuberosum) and tomato, stress the need for reconsideration of their phytosanitary risks.

First report of Tomato chlorotic dwarf viroid (TCDVd) in tomato in Norway and subsequent eradication.

“…JQ975098). Following notification to the Norwegian Food Safety Authority, the finding was confirmed in a new sample that tested positive using the conventional RT-PCR method (Verhoeven et al,2004), at Bioforsk. The disease spread from three to four plants in December 2011 to several hundred by the end of January 2012.…”

First report of Columnea latent viroid (CLVd)in Gloxinia gymnostoma, G. nematanthodes and G. purpurascens in a botanical garden in Denmark

“…2009;Nixon at al., 2009) Verhoeven et al (2004). This suggests that the viroid infection originated from the host plants' place of origin.…”

Cotton leaf curl Multan virus newly reported to be associated with cotton leaf curl disease in China

“…The 'semi-specific' PSTVd-h ⁄ c primers (Shamloul et al, 1997), the universal Vir 1 ⁄ 2 (Mumford et al, 2000) and the Vid-FW ⁄ RE (Verhoeven et al, 2004) primer sets were used. All tests gave negative results, even with the last primer sets, initially designed to detect CLVd isolates.…”