PREDICTIVE VALUE OF qPCR THRESHOLDS FOR ASSESSMENT OF MYCOTOXIN RISK ASSOCIATED WITH FUSARIUM CONTAMINATION OF MAIZE

The paper presents the results of a study of the relationship between quantitative qPCR indicators and toxinogenic potential of Fusarium isolates isolated from corn grain. The threshold detection cycle (Ct) value was determined for 55 isolates and the production of T-2 toxin, zearalenone, and fumonisin B₁ was assessed. It was found that isolates with low Ct values were characterized by higher toxinogenic activity, while an increase in Ct was accompanied by a decrease in mycotoxin levels. Correlation analysis confirmed the presence of a significant negative relationship between Ct and the total toxicity of the isolates. Logistic regression showed that each increase in Ct by one cycle reduced the probability of toxin production by approximately 70% (OR = 0.30; 95% CI: 0.16–0.58; p < 0.001). The ROC analysis results established an optimal threshold value of Ct = 25.5 cycles, which provided high sensitivity and specificity for predicting toxinogenic potential (AUC = 0.88). The obtained results indicate that qPCR quantitative indicators can be used not only for the detection of Fusarium contamination, but also as early molecular predictors of mycotoxicological risks in corn grain.