Poster Session: Detection and Diagnosis-Fungi

337-P

Development and characterization of microsatellite markers for soybean sudden death syndrome pathogen Fusarium virguliforme.
J. WANG (1), J. L. Jacobs (1), M. I. Chilvers (1)
(1) Michigan State University, East Lansing, MI, U.S.A.

Fusarium virguliforme is a soil-borne fungal pathogen and is the causal agent of soybean sudden death syndrome (SDS). SDS is a relatively new and devastating disease in the Midwest. Currently utilized DNA loci are not able to differentiate F. virguliforme isolates. Microsatellites or simple sequence repeats (SSRs) of one- to six-base DNA nucleotide motifs, often demonstrate polymorphism at the population level, are relatively inexpensive and highly informative. We developed a set of F. virguliforme microsatellite markers based on the F. virguliforme genome. In silico parameters utilized to search for the microsatellite loci were 20,14, 12, 7, 7, and 7 minimum repeats for mono-, di-, tri-, tetra-, penta- and hexa- motifs, respectively, 249 microsatellite loci qualified using these parameters. The program Primer3 was used to design primers in the flanking regions upstream and downstream (200nt) of the microsatellites, with an amplicon size range between 180 and 250bp, with these parameters primers for 108 microsatellite loci were developed. Of the 103 microsatellites tested against five isolates from four different geographic locations (MI, IL, IN and Argentina), 101 primer sets amplified PCR product and 18 (17.8%) of the microsatellite loci were found to be polymorphic. These markers will be useful for analysis of population genetic structure, movement, tracking introductions of F. virguliforme, and attempting to correlate genotypes with phenotypes.