Transferring Simple Sequence Repeat Molecular Markers from a Model to Cultivated Lotus Species: Genetic Diversity in an Association Mapping Population of Lotus tenuis

Lotus tenuis is a diploid (2n=12), out-crossing, self-incompatible, perennial species originating from the Mediterranean basin, North Africa, and Asia. On the other hand, Lotus japonicus has been selected as a model species be-cause of its simple genetic conditions (diploid, self-crossing, and short ontogenetic cycle). Lotus japonicus is currently the focus of large multinational genome projects that periodically release outstanding products; these include sequencing of genomic DNA on a large scale, generating molecular markers, and constructing high-density linkage maps (Szczyglowski and Stougaard 2008). Furthermore, comparative genetic studies have demonstrated conserva-tion of genome structure among model and crop species; this suggests that knowledge might be transferred effectively between these species. A population of 100 genotypes with divergent drought tolerance (tolerant and sensitive) was selected from INIA-Chile forage legume breeding pro-gram. This population has been physiologically and agronomically characterized under field and greenhouse drought conditions. It was recently genetically characterized with 88 simple sequence repeat (SSR) markers. Genetic and phenotypic information led to the identification of quantitative trait loci (QTLs) associated with drought tolerance of the species by association mapping analysis. The present study shows preliminary results of the molecular characterization performed with 88 SSRs developed in L. japonicus which amplified the L. tenuis genome. Genetic diversity analysis is presented in order to characterize the degree of information that SSRs provide and identify groups or structures within the population that can influence association mapping analysis.