Influence of locality and year on Fusarium species occurrence in fusarium head blight and stalk rot of winter wheat

The infestation index of fusarium stalk rot in wheat crops was significantly higher in 2004 (25.67 - 52.34 % to 12.82 - 26.75 % in 2003 year). The significantly higher level of fusarium head blight in the year 2004 (10.85 - 23.65 %) was observed in comparison with the year 2003 (0.13 - 1.73 %). In both years, the higher occurrence of fusarium stalk rot than fusarium head blight was recorded. The infestation level of fusarium head blight and fusarium stalk rot was significantly influenced by locality Vígľaš-Pstruša only (the coldest and the most moisture one). The following species spectrum was associated with fusarium head blight in evaluated localities: F. graminearum, F. culmorum, F. avenaceum, Microdochium nivale, F. poae, F. sporotrichioides, F. solani, F. sambucinum, F. tricinctum, F. oxysporum, F. chlamydosporum, F. acuminatum, F. semitectum and F. equiseti. The species spectrum isolated from fusarium stalk rot was similar, excepting F. tricinctum, F. semitectum and F. equiseti, which were isolated from stalk base from any evaluated localities. In fusarium head blight, the dominant and the most frequent species were the F. graminearum, F. culmorum and F. avenaceum, less frequent were M. nivale and F. poae. The highest frequency of M. nivale was measured in mountain and moisture locality Vígľaš-Pstruša. The other isolated species (F. sporotrichioides, F. solani, F. sambucinum, F. tricinctum, F. oxysporum, F. chlamydosporum, F. acuminatum, F. semitectum and F. equiseti) were isolated sporadically. The influence of year on Fusarium species spectrum in fusarium head blight and fusarium stalk rot was not confirmed. In fusarium stalk rot, the F. culmorum, F. avenaceum and M. nivale were the most frequent and dominant species. F. poae and F. graminearum were less frequent and the other species were isolated sporadically.