A. Haddioui et M. Baaziz, Genetic diversity of natural populations of Atriplex halimus L. in Morocco: An isoenzyme-based overview, EUPHYTICA, 121(1), 2001, pp. 99-106
Based on polyacrylamide gel electrophoresis, nine natural populations of At
riplex halimus L., a perennial shrub, collected in different regions of Mor
occo, were studied for their genetic variation using isoenzyme polymorphism
of the highly active enzyme systems: esterases (EST), acid phosphatases (A
CP) and glutamate oxaloacetate transaminase (GOT). Different allozyme frequ
encies from 7 different loci were obtained for all populations of this halo
phyte species. High levels of genetic diversity were revealed. The mean num
ber of alleles per locus (A = 1.9-2.0), the percentage of polymorphic loci
(p = 71.4-85.7) and the mean expected heterozygosity (H-e = 0.339-0.385) sh
owed an important variability in all populations. Gene diversity was essent
ially explained by the within population component. The between populations
differentiation accounted for 8% of the whole diversity (FST, averaged ove
r all loci, is 0.08). The relationships among the 9 populations were inferr
ed from the Nei's genetic distances. Four major groups were formed. The nor
thern population `Tanger', forming a unique group, was highly divergent fro
m the other groups. It appeared that the genetic distance between all group
s was related to the geographic distance that separates them.