|Shuxian, Susan - SOYBEAN PATH CENTER|
Submitted to: International Congress of Plant Pathologists
Publication Type: Proceedings
Publication Acceptance Date: January 30, 2003
Publication Date: February 1, 2003
Citation: Shuxian, S., Hartman, G.L. 2003. Biological, pathogenic, and molecular characterization of fusarium solani f. sp. glycines. International Congress of Plant Pathologists; 2003. Technical Abstract: Soybean sudden death syndrome (SDS) is caused by Fusarium solani f. sp. glycines (FSG). Over the last 5 years an internationsl collection of FSG isolates has been established and maintained at the National Soybean Pathogen Collection Center. FSG isolates grew slowly and appeared reddish light blue to dark blue on potato dextrose agar medium. Cultures produced macroconidia and chlamydospores. All isolates caused SDS sysmptions in the greenhouse pathogenicity tests, but there was a significant difference (P <0.05) among isolates for foliar disease severity, shoot and root dry weights. A protein with an estimated molecular mass of 17kDa and designeated as FISP17 for FSG-induced stress protein was identified in stem exudates of soybean seedlings root-infected with FSG. Molecular relationship between FSG and other F. solani isolates was analyzed based on the sequence of mitochondrial small subunit (Mt SSU) rDNA. All FSG isolates had identical sequences in this region. Two major lineagues were found in F. solani non-SDS causing isolates in view of the nucleotide similarity, and presence and absence of insertions. A polymerase chain reacton (PCR-based method was developed to detect DNA of FSTG. Two pairs of primers were designed based on the Mt SSU rDNA and the translation elongation factor 1-a gene. FSG DNA was detected in field-gorwn soybean roots and soil by PCR using either single pair of primers or the cobination of two pairs of primers. Molecular variability of FSG was detected using amplified fragment length polymorphism (AFLP) anlaysis.