Abstract: BACKGROUND ＆ AIM: To study the mutagenicity of the extract from Penicillium digitatum to E.coli gene. MATERIAL AND METHODS:① Reverse mutation assay and K12 infA gene mutation test were used；② The sequence of mutated infA gene was determined and analyzed. RESULTS:① The extract from penicillium digitatum significantly induced the reverse mutation of E.coli ND－160；② Five points nucleatide mutation of K12 infA gene were induced by the extract and one of them led to amino acid variation(lys→val). CONCLUSION:Penicillium digitatum have obvious mutagenic effect .

Key words: Penicillium digitatum, E.coli ND－160, K12 infA, gene mutation