Hypovirulence-associated traits in strain GD-118P-V1 of Rhizoctonai solani AG-1 IA. (A) Colony morphology. Culture characteristics of strains GD-118P, GD-118P-V1, and GD-2 on PDA plates at 28 °C for seven days. (B) Pathogenicity. The symptoms on detached rice leaves caused by isogenic strains GD-118P and GD-118P-V1, and GD-2 incubated at 28 °C for 72 h. (C and D) Comparison of average mycelial growth rate and sclerotia dry weight on PDA plates of the strains GD-118P, GD-118P-V1, and GD-2. (E) Average lesion areas caused by the strains GD-118P, GD-118P-V1, and GD-2 on detached rice leaves. In (C), (D), and (E), the data were indicated as arithmetic means ± standard error, and significant differences were assessed using the Student t test. Single asterisk (*) indicates p < 0.05, and double asterisks (**) indicate p < 0.01.