The molecular diversity studies of alfalfa (
Medicago sativa
L.) germplasm could contribute to a more precise selection
of parental populations in many breeding programs.
Sequence-related amplified polymorphism (SRAP) markers
were used to assess the genetic diversity of 110 individual
plants from 13 selected alfalfa cultivars, landraces, and
natural populations from Tunisia, Australia, Serbia, and
Kazakhstan. Ten polymorphic SRAP primer combinations
generated 137 alleles with 0.90 polymorphism information
content. The percentage of polymorphic bands per genotype
ranged from 57.66% to 70.07% with a mean of 64.29%
and overall value of 100%. The genotype Sardi 10 had the
highest value for the effective number of alleles; Nei’s gene
diversity and Shannon information index, exhibited the
highest variability level (Ne = 1.453, He = 0.259, I = 0.381,
respectively), whereas the genotype Nera exhibited the
lowest variability level (Ne = 1.359, He = 0.211, I = 0.317,
respectively). The AMOVA analysis showed that 68% of
the variance was within the genotypes; this was in line
with the coefficient of genetic differentiation (Gst = 0.370).
The genetic relatedness of alfalfa individuals analyzed by
the neighbor-joining dendrogram was consistent with the
Bayesian model-based clustering approach. The exceptions
were individuals from genotypes Slavija and Nera, which
were grouped separately by STRUCTURE analyses. These
results provide useful information for the management of
alfalfa genetic resources and the rational use of local and
foreign alfalfa populations in breeding programs focused
on the development of new, high-yielding cultivars more
adapted to drought conditions in North Africa.
