K. Persson et R. Von Bothmer, Assessing the allozyme variation in cultivars and Swedish landraces of rye(Secale cereale L.), HEREDITAS, 132(1), 2000, pp. 7-17
Genetic interpretation and diversity of 9 isozyme loci have been estimated
in 7 improved varieties and 19 landraces from Sweden by means of starch gel
electrophoresis, The isozyme systems were AGO, DIA, GPI, MDH, PGD and PGM.
For the statistic analysis we used the following measures: average number
of alleles per locus, percentage of polymorphic loci, average heterozygosit
y direct count and average heterozygosity Hardy-Weinberg expected unbiased
estimate. The measures were made on species and population levels. The dist
ribution of the total genetic diversity among populations was also calculat
ed. To illustrate the genetic relationships among populations, genetic dist
ances were measured and principal component analysis performed.
As expected in a cross-pollinated crop we found high genetic diversity and
a larger variation within than among the populations. Somewhat unexpectedly
, however, we found that the currently used varieties have the same high le
vel of heterozygosity as the landraces but in the dendrogram the two groups
are separated. The dendrogram showed three main clusters. The large cluste
r included 21 populations and the two small clusters were clearly distingui
shable from the rest. The landrace spring-type could not be separated from
the landraces winter-type, but we did detect a difference between different
spring types. A few populations had unique alleles for certain loci.