FIG. 2.

Cultural morphology of isolate DK21 and pathogenicity test. A dsRNA-containing single-conidial isolate (A) grew slowly and was deep red. A dsRNA-free isolate (B) grew fast and was pink. Through anastomosis, hygromycin-resistant colonies (C to F) that showed different cultural appearances on CM plates were selected as candidates for dsRNA transmission. The slow-growing colonies (C, D, and E) were hygromycin resistant and contained dsRNA, and the fast-growing one (F) was dsRNA free. For pathogenicity tests, conidial suspensions were inoculated onto wheat plants. Plants infected with dsRNA-free spores showed more severe symptoms than those infected with dsRNA-containing spores. CK, water-sprayed control plants.