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 ...

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 ...

‎Let $G=(V,E)$ be a graph‎. ‎A subset $Ssubset V$ is a hop dominating set‎‎if every vertex outside $S$ is at distance two from a vertex of‎‎$S$‎. ‎A hop dominating set $S$ which induces a connected subgraph‎ ‎is called a connected hop dominating set of $G$‎. ‎The‎‎connected hop domination number of $G$‎, ‎$ gamma_{ch}(G)$,‎‎‎ ‎is the minimum cardinality of a connected hop‎‎dominating set of $G$...

Weed plants characteristic for potato and hop fields have not been considered in the past as potential hosts that could transmit and lead to spreading of potato spindle tuber (PSTVd) and hop stunt (HSVd) viroids, respectively. To gain insight into this problem, we biolistically inoculated these weed plants with viroid populations either as RNA or as cDNA. New potential viroid host species, coll...

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-...

Background and Aims: Viroids are smallest known plant pathogens and cause several economically significant diseases. Until recently, viroid detection relied mainly on biological tests and indexing. Today various diagnostic techniques such as nucleic acid hybridization, southern blot and reverse transcription coupled with polymerase chain reaction (RT-PCR) are being used for detection and diag...

Citrus Bent Leaf Viroid (CBLVd) and Dwarfing (CDVd), from genus Apscaviroid, are two of the widely distributed citrus viroids among eight reported to date. They have been found induce reduction in canopy volume fruit production trees on trifoliate orange hybrids rootstocks. Moreover, infected only with CBLVd or combinations Exocortis (CEVd), Hop Stunt (HSVd) CDVd associated a poor development r...

background and aims: viroids are smallest known plant pathogens and cause several economically significant diseases. until recently, viroid detection relied mainly on biological tests and indexing. today various diagnostic techniques such as nucleic acid hybridization, southern blot and reverse transcription coupled with polymerase chain reaction (rt-pcr) are being used for detection and diagno...