Presencia de la roya naranja Puccinia kuehnii (Krüger) Butler en áreas experimentales de ca？a de azúcar (Sacharum spp. híbrido) de la región central de Cuba

symptoms of orange rust [puccinia kuehnii (krüger) butler], were identified in experimental areas of the sugar cane research station of villa clara, in central region of cuba, and its presence were confirmed by means of diagnosis of the central laboratory of plant quarantine. from 562 varieties examined, 31 were commercial varieties, 424 were parents, six were resistance patterns to brown rust and others belong to selection studies; the infection by p. kuehnii was detected in 58 varieties (10.32% of the total evaluated). p. kuehnii was identified in six commercial varieties, c1051-73, c86-12, c88-380, c89-147, c90-317 and cp52-43. the simultaneous infection was detected (coinfection) of p. kuehnii and p. melanocephala , in 17 varieties, four of them are susceptible to p. melanocephala. 62.5% of the varieties infected by p. kuehnii turned out to be resistant to p. melanocephala and 29.2% moderately resistant. the resistant patterns of p. melanocephala used in the studies, pr980 and ja64-11, were infected; it was not this way in the highly susceptible case of b4362.