INFLUENCE OF THE FUNGICIDE MATADOR (TEBUC ONAZOLE TRIADIMENOL) ON MYCOTOXIN PRODUCTION BY FUSARIUM-CULMORUM

Applications of the fungicide Matador to winter wheat (Slejpner) inocu lated at earing with Fusarium culmorum resulted in a considerable decr ease in the incidence of Fusarium headblight. In the study presented h ere, subsequent mycotoxin analyses by selected ion monitoring gas chro matography-mass spectrometry revealed higher levels of nivalenol (NIV) in samples singly treated with Matador at 1 L/ha. Amounts as high as 2432 mug NIV/kg and 860 mug NIV/kg, representing a 16- or six-fold inc rease as compared to controls, were found in wheat treated with the fu ngicide 3 h before or 24 h after inoculation of the grain with F. culm orum, respectively. In parallel, higher cytotoxic activities of these samples were obtained when testing crude sample extracts in the (4,5-d imethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-cell cultur e bioassay using swine kidney monolayers as target cells. It is conclu ded that treatment of grain with the fungicide Matador could result in a marked stimulation of the production of NIV by F. culmorum. As the incidence of Fusarium headblight did not correlate with the amount of mycotoxins found, the need for mycotoxin analyses combined with bioass ays such as the MTT-cell culture assay is recommended for a meaningful assessment of the quality of grain treated in such a manner.