Saline populations are locally adapted to salinity and flower earlier. ( A ) Soil EC increased in saline field subsites (S2, S2-a) but not in non-saline subsites (NS-a, NS-b). Note that only S2 is an original collection site. (A inset) A natural M. truncatula germinant emerging from its pod at the beginning of the field experiment (December 2008). ( B-H ) Phenotypic means and standard errors of saline origin (solid red; S1 & S2) and non-saline origin (dashed blue; NS1 & NS2) genotypes. Plants were grown in saline and non-saline field gardens ( B , F ), field-collected soils in the greenhouse ( C , G ), and 0mM and 100 mM NaCl on a common substrate ( D, E, H ). A saline origin by salinity treatment interaction is significant in panels C, D and E.