Key Points
- Take-all is a root disease of wheat and barley caused by the fungus Gaeumannomyces graminis var. tritici (Ggt).
- A number of other grass species are also susceptible to take-all.
- Break crops in wheat and barley rotations can be used to manage the inoculum levels of take-all, but grass break crops may enable inoculum to carry over to a following wheat crop. Grass crops may be hosts of take-all or may harbour susceptible grass weeds.
- Some brome grasses (ripgut, prairie and smooth brome) and kikuyu grass are highly susceptible to take-all. These species should not be present in break crops between wheat or barley crops where management of take-all inoculum is sought.
- Couch is also susceptible to take-all, and the presence of infested rhizomes increases the risk of take-all in a subsequent wheat crop.
- Take-all incidence in wheat is usually low following a one-year break in perennial ryegrass, annual ryegrass or tall fescue, but care should be taken to control wheat volunteers and grass weeds such as prairie grass and couch.