Infestation of winter wheat – monitorin of harvest samples from growers`field

In 2007 and 2008, Fusarium infestation and the content of deoxynivalenol (DON) in nine winter wheat varieties was investigated in three trials on two no-till farms. The trials formed part of a study on the feasibility of small-plot variety trials under no-till conditions. This paper mainly describes the Fusarium and mycotoxin situation. In Baggwil in 2007, the varieties Caphorn and Tapidor showed a higher incidence of head symptoms compared with other varieties. Pooled over all three trials, the resulting DON content was 10 to 15 times higher compared with the variety Arina. From the Fusarium species found on the harvested grain, F. graminearum and F. culmorum were the most prevalent species. In Baggwil in 2007, there was a surprisingly high proportion of F. culmorum, possibly dueto temporary ley as the preceding crop. The DON contents and frequencies of grain infestation with the two Fusarium species showed a strong correlation. Resistances from the list of recommended cereal varieties were confirmed by the grain infestation. According to the DON contents, however, individual varieties ought to be classified rather differently. Overall, the results demonstrate that no-till fields are highly appropriate for performing trials on Fusarium susceptibility of cereal varieties. With respect to the importance of fusaria as toxin producers, we recommend a modification of variety evaluation trials by using the criteria presented in this study including seed health test and DON analysis.