Detection method for tomato infectious chlorosis closterovirus
Tomato infectious chlorosis closterovirus has newly been described in California, US (EPPO RS 97/035). This virus occurs in glasshouses throughout California and infects several important ornamental and vegetable crops (tomato, tomatillo (Physalis ixocarpa), potato, artichoke, lettuce, petunia). It is transmitted in a semi-persistent manner by Trialeurodes vaporariorum. Tomato infectious chlorosis closterovirus (TICV) is a bipartite single-stranded RNA genome virus. It has long flexuous, filamentous particles (850 to 900 x 12 nm). Four detection methods (ELISA, Western blot, dot blot, RT-PCR) were developed, compared and used to study the distribution of TICV in plants and the relationships among isolates.
The comparative study of the four methods indicated that RT-PCR was 100-fold more sensitive than ELISA, Western blot and dot blot hybridization assays for the detection of TICV. It was also observed that TICV was detected in leaf, stem, flower and root tissues of infected tomato plants. However, the distribution of the virus within the plant was not uniform and the highest viral concentration was observed in fully developed young tomato leaves at the onset of yellowing symptoms. Five isolates of TICV were studied: three isolates from California, one from North Carolina and one from Italy (there were previously no indication that TICV was present in other US States and in Italy). No serological or molecular differences could be observed between those five isolates.
Sources
Li, R.H.; Wisler, G.C.; Liu, H.Y.; Duffus, J.E. (1998) Comparison of diagnostic techniques for detecting tomato infectious chlorosis virus.
Plant Disease, 82(1), 84-88.