| Abstract: | Gibberella fujikuroi strains isolated from rice in the United States, Asia, and other geographic areas were tested for sexual fertility with members of mating population D and for production of fumonisin B(inf1) and moniliformin in culture. Of the 59 field strains tested, 32 (54%) were able to cross with tester strains of mating population D, but only a few ascospores were produced in most of these crosses. Thirty-four strains produced more than 10 (mu)g of fumonisin B(inf1) per g, but only three strains produced more than 1000 (mu)g/g. Twenty-five strains produced more than 100 (mu)g of moniliformin per g, and 15 produced more than 1,000 (mu)g/g. Seven field strains produced both fumonisin B(inf1) and moniliformin, but none of these strains produced a high level of fumonisin B(inf1) (>1,000 (mu)g/g). However, a genetic cross between a strain that produced fumonisin B(inf1) but no moniliformin and a strain that produced moniliformin but no fumonisin B(inf1) yielded progeny that produced high levels of both toxins. Strains of G. fujikuroi isolated from rice infected with bakanae disease are similar to strains of mating population D isolated from maize in their ability to produce both fumonisins and moniliformin. This finding suggests a potential for contamination of rice with both fumonisins and moniliformin. |
