Use of allele-specific PCR of translation elongation factor 1-α gene to identify soybean sudden death syndrome pathogen (Fusarium virguliforme).

An allele-specific PCR-based method was developed to distinguish Fusarium virguliforme,the causal agent of soybean sudden death syndrome(SDS) in North America,from Fusarium phaseoli.Under the rules of allele-specific primer design,one pair of primers,Fsg-α-1/2 were synthesized based on three SNP sites on translation elongation factor 1-α gene,which could distinctively amplify F.virguliforme and produce PCR products of 327 bp.In addition,to distinguish F.virguliforme and F.phaseoli from the other Fusarium spp.,one pair of primers,Fu1/2,were designed based on the region of ITS(intergenic transcribed spacer),and produced PCR products of 452 bp.In this test,conventional AS-PCR and duplex PCR were combined to increase the sensitivity and reproducibility,Fu1/2 acting as positive control primer.Thus,AS-PCR approach provided an accurate,convenient and effective method for quick identification of F.virguliforme.