PURPOSE: To readily obtain hop stunt viroid such as hop stunt viroid cucumber variant useful in diagnosis of a plant pathogen, by detecting and fractionating the viroid with a specific DNA probe.
CONSTITUTION: DNA is synthesized according to phosphotriester method to 15W25 mer synthetic DNA probe (A) containing a base sequence expressed by the formula (a is adenine, G is guanine, C is cytosine and T is thymine) and having complementarily with RNA of hop stunt viroid grape variant (HSV-g). Then a cucumber each infected to hop stunt viroid (HSV), hop stunt cucumber variant (HSV-c) and HSV-g is extracted to afford low-molecular RNA fraction (B) containing each viroid. Then components A and B are subjected to hybridimerization while changing temperature condition and strength and weakness of the reaction is labeled with radioisotope (e.g. 32P) label to fractionate and provide the hop stunt viroids of HSV, HSV-g and HSV-g.
SANO TERUO
KUDO HIROSHI
SUGIMOTO NOBUTAKA
