[Design of a universal biotin-containing oligonucleotide diagnostic kit for detecting viroid plant diseases].

A non-radioactive diagnosticum for plant viroid diseases has been designed, based on hybridization of a biotin-labeled 26-member oligonucleotide probe with the viroid RNA site identical for potato spindle tuber viroid and chrysanthemum stunt viroid. The biotin label has been introduced into the synthetic oligonucleotide probe by the high-yield acylation of the oligonucleotide aminoalkylamide with the biotin imidazolide or N-hydroxysuccinimide ester. Hybridization techniques have been elaborated for nucleic acids isolated from plant sap. The hybrids obtained have been detected with streptavidin and biotinylated alkaline phosphatase or with the covalent conjugate of streptavidin and alkaline phosphatase, the sensitivity being as low as 1 ng. The methodology used can be applied for revealing viroids and for large scale and quick investigation of plant cell cultures.