Interaction between Bacillus subtilis and Fusarium verticillioides on fungal growth and fumonisin B1 production

L. CAVAGLIERI, S. CHULZE, M.I.RODRÍGUEZ AND M. ETCHEVERRY

Guaruya (Brasil)

Congreso; X International IUPAC symposium on mycotoxins and phycotoxins; 2000

Instituto Adolfo Lutz

This study was carried out to determine the effect of microbial interaction on Fusarium growth and fumonisin production in irradiated maize at 0.98 water activity, 25ºC over 35 days incubation period. The impact that such interaction have on Fusarium verticillioides mycelial biomass population and fumonisin production was evaluated. When the ergosterol concentration was determined at 10, 20 and 35 days of incubation period, 30, 54, 57% of reduction was observed. Population of Fusarium verticillioides (cfu per gram grain) was reduced during the incubation period. Fungal count decreased from 1 x 107 to 1 x 105 cfu/gr; from 1 x 109 to 1 x 107 cfu/gr and from 1 x 108 to 1 x 107 cfu/gr at 10, 20 and 35 days of incubation respectively. The population of Bacillus subtilis decreased with the incubation period. The strain of B. subtilis affected the fumonisin B1 production decreasing accumulation at all assayed incubation times. The percentages of reduction were 7.5; 8.6 and 47% at 10, 20 and 35 days of incubation, respectively. This study has shown that B. subtilis UNRC.CE1 can be a potential biocontrol agent on Fusarium strains which are fumonisin producers. This control method may be an alternative strategy to chemical fungicides.