Abstract: Corn southern leaf light caused by Bipolaris maydis is an important disease in maize production. It can cause great losses to the high yield and stable production in the severe years. In this paper, 30 strains were isolated from the leaf of corn southern leaf light collected from in Anhui province. The biological characteristics of mycelial growth rate, conidia production and conidia size of 30 strains were studied. The results showed that there were significant differences in the mycelial growth rate, conidia production and conidia size of different strains. The largest mycelial growth rate was FY1 strain and the smallest was BB2. The largest strain of conidia production was BB7, and the lowest strain was BB2.The conidia length of FY1 strain was the largest, and BB2 was the smallest. The conidia width of FY3 strain was the largest, and BB1 was the smallest. In addition, the colony size and color of different strains were also significantly different. The comprehensive analysis of mycelial growth rate, conidia production and colony color suggested that the mycelial grouth rate and conidia production have no positive correlation.

Key words: corn southern leaf blight, mycelial growth rate, conidial production, conidial morphology