Looking for pathogen resistance in citrus plants

REYES CA; ZANEK MC; PEÑA EJ; PLATA MI; COSTA N; GRAU O; GARCIA ML

Pucón, Chile

Congreso; XLVIII Reunión anual de la Sociedad de Biología de Chile; 2005

Sociedad de Biología de Chile

Citrus Bacterial diseases like canker, caused by the plant pathogen Xanthomonas citri, and some viral diseases such as psorosis (caused by Citrus psorosis virus, CPsV) produce important losses incitrus production in Argentina and Uruguay. Citrus psorosis is a tripartite virus and its genome consists of three ssRNAs of negative polarity. (Milne RG,Garcia ML, Moreno, P., 2003). RNA 1 carries twoopen reading frames. One of them codes for the RNA polimerase (280K) and the other for an small peptide (24K) of unknown function. RNA 2 encodes for a polypeptide of 54 kDa also of unknownfunction and RNA 3 expresses the 48 kDa. viral coat protein (Barthe et al., 1998; Sánchez de la Torre et al., 1998).The aim of this work is the generation of transgenic sweet orange plants resistant to CPsV . For that purpose we transformed plants with genetic constructions containing some CPsV gene fragments.The constructions used encode self-complementary “hairpin” RNA and they have the capacity of inducing efficiently the plant defense mechanism called Post-transcriptional gene silencing (PTGS)(Review: Baulcombe, D, 2004). A functional genomic project involving Xanthomonas citri infected and non-infected lemon plants is been prepared to know more about the host-pathogen interactions.