Absence of genetic variation in Scandinavian populations of Elymus mutabilis (Drob.) Tzvel. (Poaceae)

Elymus mutabilis (Drob.) Tzvel. is a caespitose, perennial, self-pollinatin g and allotetraploid species with a wide distribution area ranging from nor thern Europe to the north and central parts of Asia (TZVELEV 1976). It is c onsidered to be a rare taxon, but not endangered, in Scandinavia. It occurs in the most northern parts of Norway, Sweden and Finland (HYLANDER 1953). It usually has a patchy distribution pattern with populations of varying si zes. It grows on meadows, among willows and in birch forests mostly in the subalpine zone, and it:is not a morphologically variable species in Scandin avia (HYLANDER 1953). It is found alone or sympatrically with E. caninus (L .) L., E. fibrosus (Schrenk) Tzvel. and/or E. alaskanus (Scrib. ex Merr.) L ove. This study forms part of a larger investigation for analysing genetic diver sity and structure in Eurasian Elyumus species, especially from the Nordic regi(o)n. An overall aim is to establish the prerequisites for efficient co nservation strategies of the genetic diversity in Elymus (SALOMON 1995; SAL OMON et al. 1996; DIAZ et al. 1996). The genetic variation in E. mutabilis has previously been studied in a few accessions from a large geographic are a using isozymes (DIAZ et al. 1998). The present study is aimed to determin e the amount of genetic variation within and among populations of E. mutabi lis from Scandinavia by using allozymes. Allozyme electrophoresis has prove d to be useful for estimating levels of intra- and interpopulational geneti c variation (BROWN and WEIR 1983).