Phylogenetic analysis of Festuca-Lolium complex using SRAP markers

The Lolium and Festuca genera have been treated as the most important groupings of temperate grasses in forage production and the turf industry. The two genera undoubtedly represent a closely allied complex of related species. The objective of this study was to obtain an overview of the diversity and genetic relationships among 59 accessions of 32 species of the Lolium-Festuca complex using sequence related amplified polymorphism (SRAP) markers. In total, 22 primer combinations amplified 269 polymorphic bands which were detected with an average of 12.23 alleles per SRAP locus. The average polymorphic rate (P) between the species studied was 100 %, demonstrating their high degree of genetic diversity. According to the POPGENE and AMOVA analyses, the inter-genera diversity and the variance between the two genera were both under 50 %. The dendrograms derived either by NTSYS or MEGA in addition to the PCO were consistent and clearly illustrated the relationships among representatives of the Lolium genus as well as the subgenus Festuca, Schedonorus and Leucopoa within the Festuca genus. The result of this study strongly supported the previous morphological separation into a "broad leaved'' and "fine-leaved'' clades, and it once again demonstrated the close relationship between the Lolium genus and the Schedonorus subgenus. This study also suggested the inclusion of F. mairei in subg. Schedonorus and to divide subgenus Leucopoa by moving sect. Leucopoa and sect. Breviaristatae into different subgenera. The analysis method described provides new methodologies for determining the phylogeny of these outbreeding species.