Submitted to: Conference of International Organization of Citrus Virologists
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2007
Publication Date: N/A
Citation: N/A Interpretive Summary: Citrus tristeza virus (CTV) has negatively impacted Persian lime production in the Dominican Republic. This abstract describes work that will be presented at the 17th Conference of the International Organization of Citrus Virologists. CTV isolates from citrus trees of different varieties from the Dominican Republic were genetically characterized and found to be mostly mixed or single infections of the T30 and VT genotypes. This information will allow mild isolates of these genotypes to be selected for use in field experiments to provide cross-protection in Persian lime against more severe isolates of these genotypes.
Technical Abstract: Samples of citrus tissue infected with Citrus tristeza virus (CTV) were collected from Persian lime, mandarin, Washington navel, Valencia or grapefruit trees from various locations in the Dominican Republic. Desiccated tissue samples were re-hydrated and virions extracted by grinding samples in buffer. Virions were sampled from the sap extract by a magnetic bead-based immunocapture procedure using CTV-specific polyclonal antibodies. Randomly primed cDNA was synthesized from captured virions and the CTV characterized genetically by a molecular marker method in which the polymerase chain reaction (PCR) was used with primers designed to amplify specifically sequences of the T3, T30, T36, or VT genotypes of CTV. All twenty-seven samples gave a correctly-sized amplified DNA with sequence non-specific primers designed to amplify the CTV capsid protein gene. No samples yielded DNA fragments with the T3 or T36 specific primers. Based on this marker analysis, twenty-five of twenty-seven samples were mixedly infected with CTV of both the T30 and VT genotypes, while one sample was infected with the T30 genotype only and one with the VT genotype only. Though the sample size was small, the widely separated sites from which the samples were collected suggest a relatively homogeneous population of CTV dispersed throughout the Dominican Republic.