Screening of toxin production influence factors of Fusarium graminearum with predictive microbiology method

Objective To screen key factors affecting toxin production of Fusarium graminearum(F. graminearum) with predictive microbiology for prediction of toxin production under different natural conditions.Methods The L18-Hunter and Plackett-Burman(PB) models were developed based on wheat kernals,corn flakes,and rice inoculated with F.graminearum to screen the important factors(temperature,ventilatory capacity,water content,pH value,illumination,the amount and ingredients of the medium,and incubation time) which may affect the toxin production of F.graminearum.Results The results of L18-Hunter model showed that only 3-acetyl-deoxynivalenol(3-A-DON),15-aetyl-deoxynivalenol(15-A-DON) and total toxins produced by strain 3.4522 were statistically significant.The coefficients of the regression equations indicated that water content and incubation time were the key factors affecting the production of 3-A-DON,15-A-DON and total toxins by F.graminearum strain 3.4522.While the results of Plackett-Burman model designed on the basis of L18-Hunter results showed that the absolute concentration of doxynivalenol(DON) and the total toxins,logarithm concentration of DON,zearalenone(ZEN),DON and its derivatives,type B trichothecenes,and the total toxins were statistically significant(P=0.0345,0.0148,0.0022,0.0029,0.0068,0.0067,and 0.0006),respectively.The R² of the models were 0.8124,0.8616,0.9287,0.9216,0.8945,0.8951,and 0.9543,respectively.The coefficients of the regression equations showed that incubation time,temperature,and initial pH value of the matrix were the key factors for toxin production of F.graminearum strain 3.4522.Conclusion Incubation time,water content within a certain range(20-50%),temperature,and initial pH value of culture base are the key factors affecting toxins production of F.graminearum.