Detection, Identification and Quantification of Fusarium graminearum and Fusarium culmorum in Wheat Kernels by PCR Techniques

Abstract

This study was carried out on 172 samples of winter wheat. The samples consisted of various cultivars that had been randomly collected from farmers’ fields in different areas of Bavaria, South Germany. The objectives of this study were detecting the presence of Tri-5 gene producing fungus that generates trichothecene mycotoxins, especially Deoxynivalenol (DON), by using conventional qualitative PCR; determining the correlation between the presence of Tri-5 gene and DON content; evaluating the Fusarium graminearum and Fusarium culmorum infection by Real-Time PCR and estimating the correlation between DON content and the severity of F. graminearum and F. culmorum contamination. This study showed that 86% of all infected samples had a Tri-5 gene and amplified a single 544bp fragment associated with a detectable amount of DON (ranged from 10 to 2990 μg kg-1). This study demonstrated that F. graminearum is the predominant species associated with Fusarium head blight (FHB) and was considered as the predominant trichothecene producer that associated with FHB since there was a highly significant correlation (R2=0.7) between DON and F. graminearum DNA content, compared to a weak correlation (R2=0.03) between DON and DNA content of F. culmorum infected wheat kernels.