Abstract：Erianthus arundinaceus is not only an important sugarcane breeding germplasm resources, but also a potential energy grass plants, and the genetic diversity is the premise of utilization of E. arundinaceus. In this experiment, we analyzed genetic diversity of 45 accessions of E. arundinaceus collected from natural habitats in seven Chinese provinces using 20 sequence-related amplified polymorphism(SRAP) primer pairs (PPs). Results showed that: 1) 20 PPs generated 434 bands and 69% was polymorphic bands. The Nei's genetic similarity(GS) coefficient of the tested accessions ranged from 0.703 to 0.986, and the average Nei's GS coefficient was 0.842. There was rich genetic diversity among the tested wild resources of E. arundinaceus. 2) The tested accessions were clustered into 3 groups and 7 subgroups by unweighted pair-group method with arithmetic means(UPGMA) dendrogram and principal component analysis. The cluster results demonstrated a strong geographic effect on molecular variation of the local E. arundinaceus, and there was no significant relationship between genetic distance and geographic distance among accessions. 3) The genetic diversity and cluster results were affected by geographic landforms and environments, the gene flow was blocked by Ocean and mountains, and was promoted by river. A high level of genetic variation of E. arundinaceus and main impact factors of genetic variation are presented, this conclusion will be highly valuable in genetic improvement in the species per se and likely in sugarcane.
