Abstract:Two hundreds and four isolates of Rhizoctonia spp. were collected from the 270 samples of sheath and leaves of maize in Shandong, Anhui, Jiangsu, Hubei and Shaanxi provinces showing symptoms like sheath blight disease. The isolates were divided into six types of colonies and they belonged to multinucleate, binucleate and uninucleate Rhizoctonia according to the mycelium nucleates after staining with DAPI. The ratio of multinucleate, binucleate and uninucleate Rhizoctonia was 97.55%, 1.47% and 0.98% respectively. Characterization of anastomosis groups (AGs) was performed using sequencing of the 5.8S rDNA-internal transcribed spacer (ITS) region. Within the multinucleate isolates, the most prevalent AG was AG1-IA about 84.80% of all isolates, followed by WAG-Z (5.88%), AG-4-HG-I (3.43%) and AG-5 (3.43%). The binucleate Rhizoctonia isolates belonged to AG-A. The uninucleate isolates had not been identified yet. The pathogenicity potential of the Rhizoctonia isolates collected was tested. Isolates of WAG-Z, AG-4-HG-I, AG-5, AG-A and uninucleate Rhizoctonia were pathogenic, but only AG1-IA can cause typical symptoms of sheath blight on maize plants.