Occurrence of Toxic Hexadepsipeptides in Preharvest Maize Ear Rot Infected by Fusarium poae in Poland

Twenty-seven preharvest maize ears affected by Fusarium poae rot (disease score 36–100%) were selected in 1998 and 1999 in Poland and examined for the occurrence of toxic hexadepsipeptides: beauvericin (BEA), enniatin A, enniatin B and enniatin B1. The identification of F. poae was confirmed by sequence analysis of variable internal transcribed spacer regions and compared with NCBI gene bank DNA sequences. Chemical analyses were performed by HPLC-MS. In 27 ears infected by F. poae were detected: BEA (trace to 46 lg/g) in 18 samples, enniatin A (trace to 37 lg/g) in nine samples, enniatin B (trace to 47 lg/g) in 15 samples and enniatin B1 (trace to 25 lg/g) in 12 samples. When 20 strains of F. poae isolated from these samples were cultured on rice, all produced BEA (1.9–75 lg/g), three enniatin A (1.8–2 lg/g), 12 enniatin B (1.1– 5.1 lg/g) and eight enniatin B1 (1.2–5.2 lg/g). Occurrence and quantification of enniatin A, enniatin B and enniatin B1 and their co-occurrence with BEA in maize kernels is reported for the first time