HEAD BLIGHT AND BIOSYNTHESIS OF FUSARIUM TOXINS IN BARLEY KERNELS FIELD INOCULATED WITH FUSARIUM-CULMORUM

Heads of 12 spring barley genotypes (eight cultivars, four lines) were inoculated with conidial suspensions of two Fusarium culmorum isolate s (I-1 and I-2) Both isolates caused the following significant reducti ons (%) when compared with the control: number of kernels head(-1) 12 and 16, weight of 1000 kernels 47 and 24, yield 49 and 37, for I-1 and I-2 respectively. Both isolates were able to produce average levels ( mg kg(-1)) of deoxynivalenol of 67.1 and 13.9, 3-acetyldeoxynivalenol of 9.4 and 1.4 and zearalenone of 0.3 and 0.4 for I-1 and I-2 respecti vely. In kernels of three genotypes inoculated with the same isolates, 15-acetyldeoxynivalenol at an average level (mg kg(-1)) of 1.3 and 1. 5 was detected, while in kernels of six,genotypes inoculated with I-2, 0.2 of nivalenol was found. A significant correlation for yield and t oxin level was found for less pathogenic F. culmorum isolate I-2.