SUN, GENLOU. Department of Biology, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada. - Comparative studies of genetic diversity in several Elymus species.
The knowledge of genetic diversity and population structure is a
prerequisite for the successful management of conservation programs.
Genetic variability studies at the intra- and interspecific levels and
population genetic analyses depend on several factors, among which the
availability of markers with adequate variability is one of the most
important. The genetic diversity in several Eurasian Elymus
species has been characterized using isozymes, RAPDs and highly
polymorphic microsatellites both at macro- and micro-geographical
scales. Particularly, the program is concentrating on three native
species from Scandinavia, namely E. caninus (L.) L., E.
alaskanus (Scrib. ex Merr.) Löve, and E. fibrosus (Schrenk)
Tzvel.. Levels and distribution of allozyme, RAPD and microsatellite
variation in populations of Elymus fibrosus showed different
pictures of the amount of the genetic variation, but agreement was
found regarding how this genetic variation is distributed among
populations. Generally, E. fibrosus contains low genetic
variation in its populations. Genetic variability was assessed within
and among 10 E. alaskanus populations collected from Norway and
North America. Low allozymic variability was detected in these
populations, but relatively high microsatellite variation was found.
Microsatellite and allozyme results suggest that natural selection may
be an important factor in shaping the genetic diversity in three local
Norwegian E. alaskanus populations. Isozyme, RAPD and microsatellite
analysis revealed that the degree of genetic variation in E.
caninus was notably great. In general, the results indicated that
the amount of genetic diversity between different species is
different, and different markers revealed different amount of
diversity.
Key words: Elymus alaskanus, Elymus caninus, Elymus fibrosus, Genetic diversity, Microsatellites