The content of Fusarium mycotoxins, grain yield and quality of winter wheat cultivars under organic and conventional cropping systems

Nine cultivars of winter wheat were compared in organic and conventional crop rotation systems. Bread-making quality was evaluated using three parameters [thousand-kernel weight (TKW) in g, volume weight in g/l, protein content in %]. Grain yield, TKW and protein content of winter wheat in organic cropping system were significantly lower as compared to any intensity in conventional cropping system. However, clover as a preceding crop to winter wheat in organic crop rotation ensured a sufficient amount of nitrogen for grain yield, which was 6.72 t/ha on average of the three years. The requirement of the Czech national standard for bread wheat minimum value of protein content (11.5%) was met in conventional crop rotation in all cases. Average value of protein content in organic crop rotation met this limit too, but it was below the required value in two cases. The required value (760 g/l) of volume weight was met in majority of cases in organic crop rotation. The following species of the genus Fusarium were found: F. culmorum, F. graminearum, F. poae and F. avenaceum. All samples were screened for the content of deoxynivalenol (DON). There was no significant difference in the DON content between winter wheat grain from organic crop rotation and conventional crop rotation at high intensity.