Diversidad de poblaciones de Phaeoisariopsis griseola aislados de la Argentina (Diversity of Phaeoisariopsis griseola populations isolated from Argentina

STENGLEIN, S; FERMOSELLE G,; PLOPER, L.D.; VIZGARRA, O N; BALATTI, P

Villa Carlos Paz, Córdoba

Congreso; XIII Congreso Latinoamericano de Fitopatología y III Taller de la Asociación Argentina de Fitopatólogos.; 2005

ALF - AAF

Angular Leaf Spot (ALS), a disease of common bean (Phaseolus vulgaris L.), is caused by an imperfect fungus known as Phaeoisariopsis griseola (Sacc.) Ferraris. This pathogen, like others, coevolved with its host, therefore isolates also have been clustered after beans as Mesoamerican or Andean. A strategy to control the disease requires a prior knowledge of the pathogen diversity, variability and distribution. Therefore, we analyze, based on virulence and molecular markers, the variability among 45 argentinian isolates of P. griseola collected from Northwestern Argentina. Pathogenicity of the isolates was assessed on a set of 12 bean differentials and a wild bean, finding thirteen pathotypes. The wild bean turned out to be a good source of resistance to P. griseola. Different pathotypes were found on the same leaf of Andean and Mesoamerican bean genotypes which might have epidemiological implications since it increase the chances of parasexual recombination. Seven Random Amplified Polimorphic DNA (RAPD) and Inter-Simple Sequence Repeats (ISSR) primers yielded consistent polymorphic banding patterns and were used to analyze molecular diversity. Both types of markers clustered isolates of P. griseola as Mesoamerican or Andean. However, ISSR markers generated more complex amplification patterns and showed higher levels of variability among P. griseola isolates than RAPD. Financiamiento: FONCYT- PICT 08-12373, CONICET, CICBA, UNLP