Abstract: In this study, random amplified polymorphism DNA (RAPD) was used to investigate 82 accessions of Saccharum spontaneum L.from different population in Yunnan and 4 accessions of S.spontaneum L.from Indian, Thailand and Vietnam respectively. Results showed that S.spontaneum L.in Yunnan possesses abundant genetic diversity. The polymorphism were less and less when latitude and elevation increassed. Based on the results of DNA data analysis, 86 accessions of S.spontaneum L.were divided into 8 different ecotypes. The topology of the phylogenetic tree of S.spontaneum L.corresponds to their geographical distribution. The initial results indicated that S.spontaneum L. in Yunnan was probably originated from the south of Yunnan, then diffused to high elevation and high latitude of the northwest and the northdeast. We suggested that the south Yunnan was one of the possible original centers of wild sugarcane.

Key words: Saccharum spontaneum