The use of RAPD to characterize Bipolaris sorokiniana isolates.
Bipolaris sorokiniana is a phytopathogenic fungus causing diseases of cereal crops such as common root rot, the leaf spot disease, seedling blight, and black point of the grain. Random-amplified polymorphic DNA (RAPD) assay was used to investigate the genetic diversity of 20 isolates collected from different cultivars in wheat-producing regions in Brazil. Seventy primers, with random nucleotide sequences, were tested. Reproducibility to amplify the genomic DNA of isolates was found for 30 of the 70 primers tested, generating between 1 and 17 fragments ranging from 0.35 to 2.0 kb (average size). The degree of similarity between samples was calculated through simple association and the dendrogram was assessed using the unweighted pair group method with arithmetical average. After the RAPD analyses 19 isolates were closely grouped, having a similarity coefficient of >or= 78%. Isolate I017 showed very low similarity coefficients, ranging between 38 and 46%. The RAPD analyses provided important information as to the degree of genetic variability and the relationship between the isolates investigated, revealing polymorphism and establishing electrophoretic profiles useful to characterize the phytopathogen.
Departamento de Microbiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Maria Viviane Gomes
MV
Müller
José Carlos
JC
Germani
Sueli Teresinha
ST
Van Der Sand
D001203:Ascomycota / Q000145:classification* / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D016533:Mycological Typing Techniques / Q000379:methods*; D011110:Polymorphism, Genetic; D019105:Random Amplified Polymorphic DNA Technique; D015203:Reproducibility of Results
D004271:DNA, Fungal