INFLUENCES OF CHEMICAL FERTILIZERS (IN-VITRO) ON AFLATOXIN AND CITRININ SYNTHESIS BY 2 STRAINS OF ASPERGILLI

The selective effect of various levels of phosphate and nitrate (as fe rtilizers) on biosynthesis of aflatoxin by Aspergillus parasiticus var . globosus, and citrinin by A. terreus var. aureus was studied in defi ned culture medium. Phosphate at 35 - 175 mmol per 50 mL decreased afl atoxin production, but increased citrinin synthesis. Nitrate at 73 - 3 65 mmol per 50 mL stimulated the synthesis of aflatoxin but depressed that of citrinin. A rise in the levels of nitrate and phosphate led to a decrease in aflatoxin production, an increase in citrinin productio n and an accumulation of mycelial phosphate and nitrate contents.