Pathogenicity and real-time PCR detection of Fusarium spp. in wheat and barley roots

Abstract

The pathogenicity of five Fusarium spp. frequently isolated from wheat and barley roots in southern Idaho was investigated during four growth-chamber experiments and two field studies. A real-time PCR assay for quantifying the presence of F. culmorum from infected root tissue was also developed based on nucleotide sequence for the tri5 gene. Fusarium culmorum, followed by F. acuminatum and F. reticulatum, resulted in the largest root lesions and percent infected root area. However, F. semitectum, followed by F. acuminatum and F. equiseti, had the greatest impact on total root length. The TaqMan-based real-time assay was able to quantify F. culmorum in root tissue from both growth-chamber and field studies down to 61 pg. The assay also detected F. pseudograminearum and F. graminearum but could not distinguish among these three Fusarium spp.

Keywords:

• Fusarium spp.
• fusarium root rot
• quantitative detection
• trichothecene
• wheat
• barley