A tropical endophytic isolate of the fungus Fusarium verticillioides (synonym Fusarium moniliforme) obtained from Zea mays was co-transformed with plasmid pNH24 containing the Fusarium oxysporum nitrate reductase nia gene and plasmid pNOM 102 carrying the Escherichia coli b-glucuronidase gusA gene. Transformation frequency for the nia marker was 75 transformants mg-1 vector DNA and introduction of the gusA gene by co-transformation was 57.2% as indicated by the presence of the GUS+ phenotype on plates. Southern analyses confirmed the integration of both plasmids into the genome of ten GUS+ transformants. All co-transformants showed mitotic stability in respect of the GUS+ phenotype. To assess the potential of transformed endophytic fungi as vectors for introducing desirable characteristics into host tropical plants of biotechnological and agricultural importance we successfully infected maize roots and detected GUS+ phenotype”.
co-transformation; gus; nia; Fusarium verticillioides; endophyte
