Figure 4
High initial spore densities repressed the expressions of AF biosynthesis genes in A. flavus. qRT-PCR was used to analyze expressions of AF production regulators (aflR and aflS) and AF biosynthesis genes (aflO, cypA, ordA and nadA) by A. flavus A3.2890 cultured in PMS media with 104 or 106 spores/ml for 2 (A) or 3 days (B). The relative expressions were quantified by the expression level of the β-Tubulin gene. Note the expression of nadA was not repressed in the high initial spore density culture.