G Barros1, M L Chiotta, A Torres, S Chulze. 1. Departamento de Microbiología e Inmunología, Facultad de Ciencias Exactas Físico Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
Abstract
AIMS: The aims of this work were to identify potential sources of Aspergillus parasiticus inoculum and to evaluate the sclerotial and toxigenic profiles of this species from the peanut agroecosystem in Argentina. Likewise, the genetic diversity of A. parasiticus population was analysed using vegetative compatibility group (VCG) analysis. METHODS AND RESULTS: The A. parasiticus strains were isolated from soil, debris and peanut seeds in Córdoba Province, Argentina. A. parasiticus was recovered from the three sources analysed. Only 11 of 185 A. parasiticus isolates (5.9%) did not produce aflatoxins, while 57% produced sclerotia. Twenty-four VCG were identified from 63 isolates. The VCG diversity index for A. parasiticus, expressed as the number of groups divided by the total number of isolates, was 0.31. In general, there were significant differences among VCG in aflatoxin production. CONCLUSIONS: The presence of aflatoxigenic strains of A. parasiticus in the three substrates suggests that they may be an important source of aflatoxin in Argentina's peanut agroecosystem. The A. parasiticus population shows a low genetic diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study showed data on inoculum distribution, aflatoxin and sclerotia production and genetic diversity in an A. parasiticus population isolated from the peanut agroecosystem in Argentina.
AIMS: The aims of this work were to identify potential sources of Aspergillus parasiticus inoculum and to evaluate the sclerotial and toxigenic profiles of this species from the peanut agroecosystem in Argentina. Likewise, the genetic diversity of A. parasiticus population was analysed using vegetative compatibility group (VCG) analysis. METHODS AND RESULTS: The A. parasiticus strains were isolated from soil, debris and peanut seeds in Córdoba Province, Argentina. A. parasiticus was recovered from the three sources analysed. Only 11 of 185 A. parasiticus isolates (5.9%) did not produce aflatoxins, while 57% produced sclerotia. Twenty-four VCG were identified from 63 isolates. The VCG diversity index for A. parasiticus, expressed as the number of groups divided by the total number of isolates, was 0.31. In general, there were significant differences among VCG in aflatoxin production. CONCLUSIONS: The presence of aflatoxigenic strains of A. parasiticus in the three substrates suggests that they may be an important source of aflatoxin in Argentina's peanut agroecosystem. The A. parasiticus population shows a low genetic diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study showed data on inoculum distribution, aflatoxin and sclerotia production and genetic diversity in an A. parasiticus population isolated from the peanut agroecosystem in Argentina.