Rhizoctonia cerealis anastomosis group GAG-1, the common pathogen of wheat, barley and sugar beet

Abstract

Isuluies of Rhizoctonia cerealis anastomosis group GAG-1 were obtained from sharp eyespot lesions on wheat and on barley culms and from diseased sugar beet seedlings. Isolates of R. cerealis were collected from a fields with crop rotation experiments: sugar beet-spring wheat-winter barley. In pathogenicity tests isolates of R. cerealis from sugar beet seedlings and from sharp eyespot lesions on wheat and barley were pathogenic to these crops. Isolates of R. cerealis from sharp eyespot lesions on wheat and barley caused severe damping-ofTof sugar beet. Isolates of R. cerealis from sugar beet seedlings also caused symptoms of sharp eyespot on wheat and barley. None of the wheat and barley isolates of R. cerealis tested caused root-rot on wheat or barley seedlings. Isolates of R. cerealis obtained from diseased plants of wheat, barley and sugar beet were similar in morphology of cultures and anastomosed with GAG-1 tester isolate. The relatinoship between anastomosis. colony characters, growth rate, hyphal diameter and pathogenicity of AG-4. AG-2-2 and AG-5 isolates obtained together with R. cerealis from diseased plants were also investigated.