GEOGRAPHIC DISTRIBUTION AND MOLECULAR CHARACTERIZATION OF Fusarium SPECIES INFECTING SOYBEAN ROOTS

ROSATI, R; CIANCIO, L; LUQUE, A; SCANDIANI, M; SPAMPINATO, C; CERVIGNI, G D L

Rosario

Congreso; SAIB; 2014

SAIB

Soybean [Glycine max (L.) Merr] production can be largely limited by sudden death syndrome (SDS). SDS is caused by four phylogenetically related Fusarium species: F. tucumaniae (Ft), F. virguliforme (Fv), F. crassistipitatum (Fc) and F. brasiliense (Fb), all of them found in Argentina. This diversity of species and the evidence of sexual reproduction of Ft in nature offer a challenge for disease management in our country. We first studied the geographical distribution of Fusarium species considering isolates obtained from infected soybean roots from 53 different locations and 38 climatic variables and identified the predictor variables of SDS development using binary logistic regression. SDS development by Ft or Fb was explained through the intersection and maximum temperature (Tmax) on January; by Ft or Fc through the intersection and Tmax on May; by Ft and Fv through the intersection and July rainfall; by Fv or Fb through the intersection and October precipitation and by Fv or Fc only through July rainfall. No explanatory variables were identified if the SDS was developed by Fb or Fc. Then, the genetic variability within and among these species from different locations was analyzed using sequence-related amplified polymorphism, random amplified polymorphic DNA and intersimple sequence repeat markers. Correlation between locations and genetic diversity of isolates is under progress