| Summary: | Rhizoctonia-like fungi were isolated from the roots of discased wheat and barley plants sampled from the centre and periphery of bare patches and from apparently healthy plants from outside of the patches. Of the isolates recovered. 89% were multinucleate and belonged to R. solani anastomosis groups: AG-8, AG-2-2 and AG-4. The remaining isolates were binucleate Rhizoctonia spp. The multinucleate isolates of R. solani were all pathogenic. All the binucleate isolates were non-pathogenic. The AG-8 isolates of R. solani were obtained morę frequently from the plants within the patches than outside the patches. The highly virulent isolates of AG-8 were not found outside the patches. Isolates of anastomosis groups AG-2-2, AG-4 and saprotrophic isolates of AG-8 noted less frequently within the patches.
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