CONSTRUCTION OF STRAINS OF FUSARIUM GRAMINEARUM WITH HIGH PRODUCTION OF TRICHOTHECENES
禾谷镰孢菌高产毒菌株的构建*

A wild type strain (GZ3639) of Fusarium graminearum Schw. was transformed using the plasmid pGUSTRI6P5, which was constructed in this study. This plasmid consists of the promoter of TRI5 (a trichothecene biosynthetic gene), followed by a coding region of the GUS reporter gene, a copy of TRI6 (a trichothecene biosynthesis regulatory gene from F. sporotrichioides), and a hygromycin B resistance gene. Following fungal transformation, hygromycin B resistant colonies (transformants) were selected and single-spored. Transformants B4-1 and B16-1 were analyzed for GUS specific activities and 15-AcDON (15-acetyldeoxynivalenol, a species of trichothecenes) production in liquid medium. Seven days after inoculation, the selected transformants produced about 1,200 (g/ml of 15-AcDON, a 240 fold increase compared to the production by the wild type GZ3639, while both transformants had high GUS specific activities. Therefore, there was a positive correlation between GUS specific activities and 15-AcDON production. Thus, B4-1 and B16-1 are useful tools for study on interaction between F. graminearum and its host wheat in relation of trichothecenes.