PRODUCTION OF VIRUS-FREE DAHLIA BY: MERISTEM-CULTURE AND VIRUS DETECTION THROUGH CDNA PROBES AND ELISA

Meristem propagation procedures which have shown promising results in obtaining healthy dahlia from plants known to be infected by DaMV, or DaMV and CMV complex and, in following rapid micropropagation in-vitro are described.
Factors investigated included the cultivars, the growth substance composition, the period of meristem excision, the origin of meristems (terminal or axillary buds) and the effect of lighting under cultivation.
With the cultivars "Angers", "Chambord", "Fatima" and "Thomas Edison", the efficiency of virus elimination following 6 months of indexing, was 100 %, 84,2 %, 85,8 and 81,2 % respectively.

The ELISA and dot-blot hybridization techniques have been used for detecting dahlia disease viruses.
Both methods were performed to detect the presence of CMV and DaMV, using nicotine and urea in extract buffer, in leaves, stems and tubers.
The hybridization assays were compared to ELISA for detecting DaMV. The hybridization metrods using either radioactively or non-radioactively labeled DNA as probes for DaMV detection were extremely sensitive and with the adopted extraction and alkaline hydrolysis treatement, detection of 1 pg/spot purified DNA, 2 ng/ml purified virus and 1/10000 dilution of infected plant extracts were possible.
This method can be used as a rapid screening procedure for the virus with very small tissue samples.

VII International Symposium on Virus Diseases of Ornamental Plants

W. CAI, M. TRONCHET, N. LARROQUE, N. DORION, J. ALBOUY

https://doi.org/10.17660/ActaHortic.1988.234.50