|Riassunto in Inglese:|
Peach latent mosaic is a worldwide disease caused by Peach latent mosaic viroid (PLMVd). The main symptoms induced by the viroid are reduction of fruit quality and tree vigor and increased susceptibility to other biotic and abiotic stress. Moreover, infected trees show a delay in leaf emergence, flowering and maturity, malformation of fruits with cracked sutures and enlarged pits, bud necrosis and an early decline. A new primer pair and a probe were designed in order to perform a real-time reverse transcription-polymerase chain reaction (rt-RT-PCR) assay based on TaqMan™ chemistry. The method was tested for its sensitivity, reproducibility and specificity. The sensitivity of the rt-RT-PCR has been evaluated with dilution series of in vitro transcripts from a whole PLMVd genome cloned in a plasmid .The dilutions were used as standard for quantification of viral template in infected samples.
The method has been also evaluated for its specificity using healthy peach, apricot, plum and pear controls and non-target viroids (Apple scar skin viroid, Hop stunt viroid, Pear blister canker viroid and Potato spinder tuber viroid).
PLMVd was detected in total RNA samples extracted from GF 305 infected controls and from leaves and fruits of peach, plum, apricot, wild pear, quince and pear trees collected in open field.