PRODUCTION OF FUMONISIN B-1 AND MONILIFORMIN BY GIBBERELLA-FUJIKUROI FROM RICE FROM VARIOUS GEOGRAPHIC AREAS

Gibberella fujikuroi strains isolated from rice in the United States, Asia, and other geographic areas mere tested for sexual fertility with members of mating population D and for production of fumonisin B-1 an d moniliformin in culture. Of the 59 field strains tested, 32 (54%) we re able to cross with tester strains of mating population D, but only a few ascospores were produced in most of these crosses, Thirty-four s trains produced more than 10 mu g of fumonisin B-1 per g, hut only thr ee strains produced more than 1000 mu g/g. Twenty-five strains produce d more than 100 mu g of moniliformin per g, and 15 produced more than 1,000 mu g/g. Seven held strains produced both fumonisin B-1 and monil iformin, but none of these strains produced a high level of fumonisin B-1 (>1,000 mu g/g). However, a genetic cross between a strain that pr oduced fumonisin B, but no moniliformin and a strain that produced mon iliformin but no fumonisin B-1 yielded progeny that produced high leve ls of both toxins, Strains of G. fujikuroi isolated from rice infected with bakanae disease are similar to strains of mating population D is olated from maize in their ability to produce both fumonisins and moni liformin, This finding suggests a potential for contamination of rice with both fumonisins and moniliformin.