Molecular tests for routine diagnosis of Chrysanthemum stunt pospiviroid
In Italy, two molecular tests were developed to detect Chrysanthemum stunt pospiviroid (EPPO A2 list): a tissue blot hybridization assay and a one tube-one step RT-PCR. These tests were evaluated on chrysanthemum material at a flower-producing company in Central Italy which followed a certification scheme to verify the absence of CSVd during the production and selection of new cultivars and hybrids. Both techniques were found sensitive and reliable for CSVd in routine diagnosis. Tissue blot hybridization assay was preferable when large numbers of samples had to be tested (fresh leaf samples could be rapidly processed and imprinted membranes could then be stored at 4°C before subsequent viroid detection, low cost). RT-PCR was found useful when limited number of samples had to be tested, and in particular for testing in vitro nuclear stock plants, as only a small amount of plant tissue is needed. During this study, 267 plantlets belonging to 84 in vitro nuclear stock plants (corresponding to 39 varieties and 45 hybrids) and more than 2500 samples of leaf cuttings were tested. Only one chrysanthemum variety was found infected by CSVd and immediately eliminated.
Tomassoli L, Faggioli F, Zaccaria A, Caccia R, Albani M, Barba M (2004) Molecular diagnosis of Chrysanthemum stunt viroid for routine indexing.
Phytopathologia Mediterranea 43(2), 285-288.