Eradication and diversity of potato spindle tuber viroid in Dahlia in Japan

Abstract The potato spindle tuber viroid (PSTVd) was discovered in 2009 in Japanese dahlia (Dahlia sp.). Their occurrence areas were distributed across 24 prefectures based on an exhaustive survey using RT-PCR and RT-qPCR. All dahlia plant varieties in which PSTVd was detected and their adjacent plants were removed from the field. This was repeated until the eradication was completed in 2021. Phylogenetic analyses revealed that the collected PSTVds were closely related which suggests that PSTVd was widespread from the same point from infected seedlings and tubers in Japan.