Genetic variation among vegetative compatibility groups of Fusarium oxysporum f. sp. cubense analyzed by DNA fingerprinting

• Published in: Phytopathology 1998-12, Vol.88 (12), p.1283-1293
• Main Authors: Bentley, S. (University of Queensland, St. Lucia.), Pegg, K.G, Moore, N.Y, Davis, R.D, Buddenhagen, I.W
• Format: Article
• Language: English
• Subjects: ADN; AGENT PATHOGENE; Biological and medical sciences; BIOTIPOS; BIOTYPE; BIOTYPES; DNA; DNA AMPLIFICATION; DNA FINGERPRINTING; EMPREINTE ADN; ENFERMEDADES FUNGOSAS; Fundamental and applied biological sciences. Psychology; FUNGAL DISEASES; Fungal plant pathogens; FUSARIUM OXYSPORUM; FUSARIUM OXYSPORUM F.SP. CUBENSE; GENETIC VARIATION; GEOGRAPHICAL RACES; HELICONIA; HUELLAS GENETICAS ADN; MALADIE FONGIQUE; MUSA; ORGANISMOS PATOGENOS; PATHOGENICITY; PATHOGENS; PATHOTYPE; PATHOTYPES; PATOGENICIDAD; PATOTIPOS; PHYSIOLOGICAL RACES; Phytopathology. Animal pests. Plant and forest protection; POUVOIR PATHOGENE; RACE PHYSIOLOGIQUE; RAZAS FISIOLOGICAS; VARIACION GENETICA; VARIATION GENETIQUE; Variation, races, biotypes, parasitic specialization, genetics
• ISSN: 0031-949X; 1943-7684
• DOI: 10.1094/PHYTO.1998.88.12.1283

ABSTRACT Genetic variation within a worldwide collection of 208 isolates of Fu-sarium oxysporum f. sp. cubense, representing physiological races 1, 2, 3, and 4 and the 20 reported vegetative compatibility groups (VCGs), was analyzed using modified DNA amplification fingerprinting. Also characterized were 133 isolates that did not belong to any of the reported VCGs of F. oxysporum f. sp. cubense including race 3 isolates from a Heliconia species and isolates from a symptomatic wild banana species growing in the jungle in peninsular Malaysia. The DNA fingerprint patterns were generally VCG specific, irrespective of geographic or host origin. A total of 33 different genotypes were identified within F. oxysporum f. sp. cu-bense; 19 genotypes were distinguished among the isolates that belonged to the 20 reported VCGs, and 14 new genotypes were identified among the isolates that did not belong to any of the existing VCGs. DNA fingerprinting analysis also allowed differentiation of nine clonal lineages within F. oxysporum f. sp. cubense. Five of these lineages each contained numerous closely related VCGs and genotypes, and the remaining four lineages each contained a single genotype. The genetic diversity and geographic distribution of several of these lineages of F. oxysporum f. sp. cubense suggests that they have coevolved with edible bananas and their wild diploid progenitors in Asia. DNA fingerprinting analysis of isolates from the wild pathosystem provides further evidence for the coevolution hypothesis. The genetic isolation and limited geographic distribution of four of the lineages of F. oxysporum f. sp. cubense suggests that the pathogen has also arisen independently, both within and outside of the center of origin of the host.