Exploring the genetic diversity of Cynodon radiatus (Poaceae) accessions using ISSR markers

Inter-simple sequence repeat (ISSR) markers were applied to determine the genetic relationship among 29 Cynodon radiatus accessions from different regions of China. Fifty ISSR primers were screened, and 14 primers were selected for their capability to produce clear and reproducible patterns of multiple bands to amplify specific C. radiatus genomic sequences. A total of 189 ISSR fragments from 300 bp to 3000 bp were amplified, of which 98.94% were polymorphic. Genetic similarity coefficients among the 29 accessions ranged from 0.45 to 0.90, with an average of 0.68. Cluster analysis by 2 methods, unweighted pair-group method with arithmetic averages and principle coordinate analysis, showed that the C. radiatus accessions clustered into 4 distinct groups. A high level of variation exists in C. radiatus accessions. The present study shows that the ISSR technique is a powerful method for the identification and molecular classification of C. radiatus accessions, and for the determination of their genetic relationships. (C) 2012 Published by Elsevier Ltd.