Characterization of the formae speciales of Fusarium oxysporum causing wilts of cucurbits by DNA fingerprinting with nuclear repetitive DNA sequences

• Published in: Applied and Environmental Microbiology Vol. 60; no. 8; pp. 2684 - 2691
• Main Authors: Namiki, F, Shiomi, T, Kayamura, T, Tsuge, T
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01.08.1994
• Subjects: ADN; Agriculture; Agronomy. Soil science and plant productions; Biological and medical sciences; Cellular biology; Classical genetics, quantitative genetics, hybrids; Cloning, Molecular; CUCUMIS MELO; CUCURBITACEAE; DNA Fingerprinting; DNA, Fungal - analysis; FILOGENIA; FLETRISSEMENT; Fruits; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Fungi; Fusarium - genetics; FUSARIUM OXYSPORUM; Genetic Variation - genetics; Genetics; Genetics of eukaryotes. Biological and molecular evolution; IDENTIFICACION; IDENTIFICATION; JAPON; MARCHITEZ; PHYLOGENIE; Phylogeny; Phytopathology. Animal pests. Plant and forest protection; Plant Diseases - microbiology; Plants - microbiology; POLIMORFISMO GENETICO; POLYMORPHISME GENETIQUE; Repetitive Sequences, Nucleic Acid; Thallophyta, bryophyta; Variation, races, biotypes, parasitic specialization, genetics; Vegetals; Fusarium oxysporum; Typing; Genetic marker; Plant pathogen; Pathogenesis; Genetic variant; Cucurbitaceae; Host specificity; Genetic distance; Phylogeny; Intermediate repeated sequence; Fungi; Dicotyledones; Fingerprint method; Angiospermae; Spermatophyta; Fungi Imperfecti; Thallophyta
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/AEM.60.8.2684-2691.1994

The genetic relatedness of five formae speciales of Fusarium oxysporum causing wilts of cucurbit plants was determined by DNA fingerprinting with the moderately repetitive DNA sequences FOLR1 to FOLR4. The four FOLR clones were chosen from a genomic library made from F. oxysporum f. sp. lagenariae 03-05118. Total DNAs from 50 strains representing five cucurbit-infecting formae speciales, cucumerinum, melonis, lagenariae, niveum, and momordicae, and 6 strains of formae speciales pathogenic to other plants were digested with EcoRV and hybridized with 32P-labeled FOLR probes. The strains were clearly distinguishable at the formae specialis level on the basis of FOLR DNA fingerprints. Fifty-two fingerprint types were detected among the 56 strains by using all FOLR probes. These probes were used to infer phylogenetic relationships among the DNA fingerprint types by the unweighted pair group method using averages and parsimony analysis. The fingerprint types detected in each of the formae speciales cucumerinum, lagenariae, niveum, and momordicae were grouped into a single cluster. However, two different genetic groups occurred in the formae specialis melonis. The two groups also differed in pathogenicity: one group caused wilts of muskmelon and oriental melon, while the second was pathogenic only to muskmelon. The fingerprint types of different formae speciales pathogenic to plants other than cucurbits were distinguishable from one another and from the fingerprints of the cucurbit-infecting strains. These results suggest that the cucurbit-infecting formae speciales are intraspecific variants distinguishable at the DNA level and in their host range