Revista mexicana de ciencias agrícolas
versão impressa ISSN 2007-0934
MARISCAL AMARO, Luis Antonio et al. Selection of oat genotypes for the identification of stem rust races. Rev. Mex. Cienc. Agríc [online]. 2011, vol.2, n.4, pp. 593-600. ISSN 2007-0934.
Identification of physiological races of Puccinia graminis f. sp. avenae using differentials, is important in oat's genetic improvement programs, in order to obtain resistance to stem rust and learn about evolution and regional spread of the pathogen. In 2008-2009, in greenhouses of CIMMYT, El Batan, Mexico, 50 monopustule isolates of P. graminis f. sp. avenae were tested in 24 genotypes of oat (Avena sativa L.), in order to determine the pathogen diversity in samples collected in six states of Mexico and see if these genotypes could be used as differential plants. Genotypes Avemex, Obsidiana, Papigochi, Diamante, Raramuri, Chihuahua and Progenitor 7, expressed different types of infection and can be used as differentials to study pathogen diversity and races prevalence. Using these differentials, 24 different races of the pathogen were found. This leads to the conclusion that there is great genetic variability of the fungus in the sampled regions. Against isolates tested, it was noted that Agata, Avena desnuda, Menonita and Saia varieties, showed the highest resistance level and progenitors 11, 12 and 13 and varieties 12, 14, 27, 28, 36, 43 and 44 had good resistance level, so they can be used as progenitors in future crosses plans.
Palavras-chave : Puccinia graminis f. sp. avenae; genetic diversity; monopustule isolates.