Characterization of Fusarium langsethiae isolated from wheat kernels in Italy

Among seed-borne fungi present on wheat kernels (Triticum durum Desf. and T. aestivum L.), several Fusarium species are of interest due to their ability to produce mycotoxins. Fusarium langsethiae, a species producing type A trichotecenes (T2 and HT2 toxins) harmful to humans and cattle, has been recently isolated from durum and common wheat kernels coltivated in central and southern Italy. Toxin production of seven F. langsethiae isolates grown on autodaved wheat kernels was measured with the ELISA Ridascreen T2 kit (Biopharm, Glasgow, UK). Some isolates were positive for T2 production. The pathogenicity of one isolate (ISPaVe ER-1409) was evaluated in the open field by spraying plants of cv. Simeto at the 10.5.2 Feeke's scale growth stage with a suspension of 1x10 super(5) spores ml super(-1) of the fungus. F. graminearum (ITEM 1852) and F. culmorum (ITEM 1851) were inoculated at the same concentration of F. langsethiae for symptom comparison. Controls were sprayed only with water. For each species, 0.8 m super(2) plots with three replicate were inoculated. To maintain high humidity levels, plants within each plot were covered with plastic bags for 48 h. Typical Fusarium head blight symptoms developed after 15 days only on spikes inoculated with F. graminearum and F. culmorum with a McKinney severity of 87.2 and 89.8, respectively while no differences with the control were observed on plants inoculated with F. langsethiae. Epidemiological studies are in progress to assess the distribution and the incidence of this fungus in Italy.