Caracterización patogénica y genética de aislamientos Mexicanos de Fusarium solani f. Sp. phaseoli (Burk.) Snyd. & Hans

Throughout Mexico, fungi from genus Fusarium causes root rot in common beans which results in substantial yield losses. Disease epidemiology and fungal/ plant population genetics are poorly understood. Common beans growing in four states of Mexico (Aguascalientes, Veracruz, Guanajuato, Mexico) were sampled. Forty-eight Fusarium solani f. sp. phaseoli (FSP) isolates were obtained and identified and then analyzed for conidia size, in vitro growth rate, pathogenicity in twelve common bean cultivars, and Amplified Fragment Length Polymorphisms (AFLP) genotype in order to characterize genetic diversity patterns and to identify relationships among them. Significant differences were found in morphology, pathogenicity and AFLP genotype amongst the various isolates. Isolates from Veracruz, Guanajuato, and Aguascalientes grew faster in vitro than those from México and showed the largest conidia. The most pathogenic FSP isolates were from Aguascalientes and Mexico. Bean cultivars with black seed coat (from Mesoamerica and Durango races) and cv. Pinto Villa (from Durango race) showed the highest frequencies of resistance reactions to most of FSP isolates. Isolates from the state of Mexico were genetically different from the other isolates with genetic dissimilarity >9%.