Novel approaches to evaluate the genetic diversity of Citrus Tristeza Virus
Abstract: The identification and characterization of different isolates of Citrus tristeza virus(CTV) is one of the most useful tool to control the epidemic spread of the disease at a spatialscale and the potential dissemination of the virus. SSCP (Single Strand ConformationPolymorphism), based on the conformation of single-stranded DNA, is till now the mostcommon approach routinely used. In our lab we evaluated the capability of two novelprotocols based on capillary electrophoresis (CE-SSCP) and High Resolution Meltinganalysis (HRM) to differentiate the virus isolates. CE-SSCP analysis of four CTV isolates,characterized by biological indexing and partial sequencing, showed that the protocol issuitable for a rapid preliminary screening of CTV genetic diversity in a large number ofsamples, also with mixed infections, on several genomic regions at one time. HRM analysisidentified sequence polymorphisms, allowing to easily distinguish and categorize differentisolates in a single tube reaction. Both protocols are very suitable for characterization andclassification of CTV isolates, prior or in alternative to sequencing. Being fast, flexible andcomplementary they can be helpful to give a large number of information in many samplesin a short time.