The report records a number of researches developed to characterize variability in X.albilineans populations, causing agent of sugarcane foliar climbing, one of the main sugarcane desease in Cuba and the rest of the world, after the outbreaks start in 1998. this desease outbreaks for the first time in Cuba in 1979 and was considered under controled and in national quarantine since 1982. From 1994 on, latent infections were detected in vitropplants, thus a preventing work was done on the danger of its reemergence, what began in 1998 with a change in the desease symtomology.

The research records the study of X. albilineans populations variability in the country and of international refference strains, which were characterized through culture, biochenical and molecular studies (nested-PCR and repetitive-PCR)

the study includes:

a)That the current foliar climbing outbreak in cuba have been produced by new bacterium variants non previously detected in Cuba; presenting a great homology to the B-01 (PFGE) gruop from Florida and Texas, identified as the causing agent of the desease explosive reemergence in the region whhich are different from the cuban isolations present in latent infections on vitroplants;

b) They present variations reffering to physiology, morphology of bacterial;

c) The presence of Xanthomonas albilineans serovar I, being evident the existence of other two variants corresponding to serovar II and III;

d) A total of 11 bacterial genonic groups were identified, conformed by the happlotypes BOX, ERIC y REP, denominated GG1, GG3, GG4, GG6, GG7, GG10, GG13, GG14 y GG15, being GG1 and GG4 the most frequent;

e) Doble antibody UMELISA and nested-PCR methods were evaluated for the diagnosis of all bacterial variants in the country with an effectiveness over 97%;

f) The desease was detected in a numerous group of clones from the country´s germoplasm bank and some productive areas.

It count on the references given by international personalitie and national institution such as the National Institute for Sugarcane Research (INICA), the Ministry of Sugar (MINAZ) and the National Scientific and Technological Program of Agricultural Biotechnology.There are some refferences made on the results publications in cuba and abroad,

It has practical importance since it allows reinforcing the national Phytosanitary Surveillance System and the possibility, with the created and validated diagnosis sytems, to develope a new Epidemiological Surveillance Sytem against the deseas. This research results have been included in a methodology for the survey on climbing of the program of actions to be adopted to prevent and manage the desease, and which have been used as far as the material resources have alowed it.