Highly purified isolates of potato spindle tuber viroid (PSTV) from Lycopersicon esculentum cv. Rutgers and citrus exocortis viroid (CEV) from Gynura aurantiaca have been compared. Two-dimensional fingerprinting analysis of PSTVand CEV-RNA labeled in vitro with lzrI has demonstrated that (i) each of these RNA species has a complexity compatible with the size estimate of 250X350 nucleotides and ...

Background and Aims: Citrus exocortis disease is naturally limited to citrus plants and causes a serious disease on sensitive rootstocks such as trifoliate orange. The aim of this study was to sample new variants of citrus exocortis viroid from Fars trees with yellowing and suberization symptoms and comparison with other isolates of this viroid. Materials and Methods: A number of symptomat...

A major challenge in the agricultural industry is the development of techniques that can screen plant samples for viroid infection. Microarrays are promising in this regard, as their high throughput nature can potentially allow for the detection of a range of viroids in a single test. In this paper we present a microarray that can detect a wide spectrum of all 8 reported viroid genera including...

An effi cient method for RNA extraction that leads to RNA high yield and purity is a technical issue relevant for development and optimization of molecular diagnostic methods aimed to detect viroid infections in citrus varieties. Residual contaminants may affect RNA detection depending on the molecular diagnosis approaches. This condition can be evaluated through RNA absorption spectrum analysi...

background and aims: plant certification programs need reliable, fast, cheap and sensitive methods for detection of systemic pathogens with special interest in virus and viroid detection. reverse transcriptase-polymerase chain reaction (rt-pcr) has been documented as an alternative assay for certification of plant propagating materials. the main object of the present study was the optimization ...

Viroids are small, circular, single-stranded RNA molecules that, while not coding for any protein, cause several plant diseases. Viroids rely for their infectious cycle on host proteins, most of which are likely to be involved in endogenous RNA-mediated phenomena. Therefore, characterization of host factors interacting with the viroid may contribute to the elucidation of RNA-related pathways of...

Background and Aims: Plant certification programs need reliable, fast, cheap and sensitive methods for detection of systemic pathogens with special interest in virus and viroid detection. Reverse transcriptase-polymerase chain reaction (RT-PCR) has been documented as an alternative assay for certification of plant propagating materials. The main object of the present study was the optimization ...

Abstract Viroids are smallest, single-stranded, circular, highly structured plant pathogenic RNAs that do not code for any protein. Viroids belong to two families, the Avsunviroidae and the Pospiviroidae. Members of the Pospiviroidae family adopt a rod-like secondary structure. In this study the most stable secondary structures of citrus viroid variants that reported from Fars province wer...

Nucleotide sequences were determined for two hop stunt viroid-related Group II citrus viroids characterized as either a cachexia disease non-pathogenic variant (CVd-IIa) or a pathogenic variant (CVd-IIb). Sequence identity between the two variants of 95.6% indicated a conserved genome with the principal region of nucleotide difference clustered in the variable (V) domain. Full-length viroid RT-...