Submitted to: Mycologia
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/16/1999
Publication Date: N/A
Citation: Interpretive Summary: Species in the filamentous fungal genus Fusarium impact on human health and safety because they are responsible for many significant diseases of cereal crops, and the many potent toxins these fungi produce contaminate food and feed. The purpose of this study was to investigate the identity and genetic relationships of Group 1 and 2 strains of Fusarium graminearum using biochemical [i.e., molecular genetics], morphological and physiological methods. Results of the molecular genetic, morphological, and mating experiments each independently indicate that the Group 1 strains previously identified as F. graminearum represent an undescribed species which we describe and illustrate as F. pseudograminearum. A molecular diagnostic test was developed that makes it possible to rapidly and accurately detect and identify this toxigenic wheat pathogen for the first time, thereby minimizing the impact of this mold and its toxins on food safety and human and animal health.
Technical Abstract: Fusarium pseudograminearum sp. nov., formally known as F. graminearum group 1, is described and illustrated. F. pseudograminearum can be distinguished from F. graminearum based on difference in colony growth rates, widest position of conidia, different reactions to BLB light concerning the length of 3- and 5-septate conidia, and absence of homothalic production of perithecia. Maximum parsimony analysis of DNA sequences from the Beta-tubulin gene introns and exons indicate that F. pseudograminearum represents a phylogenetically distinct species that is a sister group to a F. graminearum-F. lunulosporum-F. culmorum clade. DNA sequence data from the translation elongation factor (EF-1alpha) gene were used to develop a PCR primer pair which specifically amplified DNA from all isolates of Fusarium pseudograminearum tested.