Specific identification of Fusarium graminearum by PCR with gaoA targeted primers

A duplex PCR procedure for the specific identification of Fusarium graminearum was set up and optimized for high sensitivity. The specific primer pair used was originally designed for the detection of a galactose oxidase producing F. gramineaurum-strain previously designated Cladobotryum dendroides NRRL 2903. Results obtained in this study suggest identification of this strain as F. graminearum. The PCR procedure gave a specific 900 bp amplificate with DNA isolated from F. graminearum (and from C. dendroides NRRL 2903). No amplification occurred with DNA from closely related Fusarium species, fungi of other genera, bacteria and cereals. The method was used for screening of 22 strains originally designated F. graminearum. Results were compared to morphological characteristics of the isolates, red pigmentation on mannitol-PCNB-agar, and production of galactose oxidase by a novel colorimetric detection system for this enzyme. Negative results in specific amplification with some of the isolates were in good accordance with physiological and morphological characterization. The value of this highly specific method for the detection of F. graminearum in natural habitats is discussed.