A GENERAL BIOTIN-CONTAINING OLIGONUCLEOTI DE DIAGNOSTICUM FOR PLANT VIROID DISEASES

A non-radioactive diagnosticum for plant viroid diseases has been desi gned, based on hybridization of a biotin-labeled 26-member oligonucleo tide probe with the viroid RNA site identical for potato spindle tuber viroid and chrysanthemum stunt viroid. The biotin label has been intr oduced into the synthetic oligonucleotide probe by the high-yield acyl ation of the oligonucleotide aminoalkylamide with the biotin imidazoli de or N-hydroxysuccinimide ester. Hybridization techniques have been e laborated for nucleic acids isolated from plant sap. The hybrids obtai ned have been detected with streptavidin and biotinylated alkaline pho sphatase or with the covalent conjugate of streptavidin and alkaline p hosphatase, the sensitivity being as low as 1 ng. The methodology used can be applied for revealing viroids and for large scale and quick in vestigation of plant cell cultures.