A commentary on Invasion of shoot apical meristems by Chrysanthemum stunt viroid differs among Argyranthemum cultivars Given that they do not encode proteins, viroid RNAs are extremely dependent on host factors for completing their infection cycle. This cycle consists of: (i) access to the organelle wherein they are replicated, the nucleus in the family Pospiviroidae (type member potato spindle...

australian grapevine viroid (agvd), an apscaviroid of the family pospiviroidae, was recently identified in vineyards of southern iran. it had a relatively wide host range and caused stunting, leaf deformation, mottling and vein clearing in experimental hosts upon mechanical inoculation of nucleic acid extracts or agroinfiltration of the viroid infectious cloned dna. predicted secondary structur...

The rolling circle replication of the small, single-stranded viroid RNAs requires a specific processing reaction to produce monomeric RNAs that are ligated into the final circular form. For avocado sunblotch viroid, peach latent mosaic viroid, and chrysanthemum chlorotic mottle viroid, the hammerhead self-cleavage reaction is considered to provide this processing reaction. We have searched for ...

A viroid was isolated from Iresine herbstii plants using the bidirectional PAGE method for analysis of small circular RNA molecules. The viroid was transmitted to viroid-free Iresine herbstii plants of the cultivar 'Aureoreticulata' by mechanical inoculation. Infected plants did not develop any symptoms. The new viroid species has been named Iresine viroid (IrVd). It is a member of the potato s...

Hop stunt viroid RNA (HSV) has been detected by molecular hybridization in stunted plants of the Japanese cultivar Kirin II cultivated in Korea (1,2). For propagation, the viroid was transmitted to the wild curcarbU Benincasa Mspida which developed HSV-spedfic severe growth retardation. Isolation, purification, reverse transcription of the viroid-RNA with aid of viroid-specific primers, and seq...

Increasing evidence indicates that the phloem mediates traffic of selective RNAs within a plant. How an RNA enters, moves in, and exits the phloem is poorly understood. Potato spindle tuber viroid (PSTVd) is a pathogenic RNA that does not encode proteins and is not encapsidated, and yet it replicates autonomously and traffics systemically within an infected plant. The viroid RNA genome must int...

Head of Corporate Implementation and Consultancy Unit, Malaysian Palm Oil Board. 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia. Tel: 03-8769 4574 Fax: 03-8926 1337 E-mail: tot@mpob.gov.my Website: www.mpob.gov.my he oil palm is an important perennial oil crop for a number of countries in the tropics. A recent finding reported the presence of Coconut cadang-cadang v...

Despite the non-coding nature of their small RNA genomes, the visible symptoms of viroid infection resemble those associated with many plant virus diseases. Recent evidence indicates that viroid-derived small RNAs acting through host RNA silencing pathways play a key role in viroid pathogenicity. Host responses to viroid infection are complex, involving signaling cascades containing host-encode...