Antifungal compounds in winter wheat resistant and susceptible to Septoria nodorum

The content of benzoxazinone compounds in Septoria nodorum resistant and susceptible wheat cultivars fell with time, reaching an undetectable level 3–4 wk after germination. The compounds were absent from field-grown plants extracted at growth stages 2–3, 6–7, 10, 10.5 and 11. Additional antifungal compounds were detected in healthy and diseased field-grown plants of both cultivars at all growth stages, although qualitative and quantitative differences in inhibitory activity were small and their role in resistance remains open to discussion.