Phytotoxicity of eight mycotoxins associated with fusarium in wheat head blight

The study of eight mycotoxins from Fusarium spp. at concentrations ranging from 0 to 4.3 mg/L for deoxynivalenol, 3-acetyldeoxynivalenol, nivalenol, a nd a culture filtrate, and from 0 to 14.3 mg/L for T2 toxin, HT2 toxin, dia cetoxyscirpenol, and zearalenone, demonstrate that trichothecenes are phyto toxic. The inhibition of coleoptile elongation by each trichothecene is wel l described by a linear equation and these compounds show differences in ph ytotoxicity. Deoxynivalenol and 3-acetyldeoxynivalenol are 2.5 times more t oxic than T2 toxin, 8 times more toxic than HT2 toxin. and 13 times more to xic than diacetoxyscirpenol. The culture filtrate, which contains deoxyniva lenol and 3-acetyldeoxynivalenol, is the most toxic to the coleoptile. A mi xture of four purified trichothecenes, deoxynivalenol, 3-acetyldeoxynivalen ol, T2 toxin, and nivalenol, revealed differences in trichothecene suscepti bility among 11 wheat cultivars. Moreover, reduction of coleoptile elongati on of these cultivars was correlated with scabsusceptibility (r = 0.74; P = 0.0068).