SSR and cpDNA marker dataset genetic integrity of M.sylvestris in Saxony, Germany

Malus sylvestris (Mill.) is the only indigenous wild apple species in
Central Europe. Agriculture, forestry and urbanization increasingly
endanger Malus sylvestris natural habitats. In addition, the risks of
cross-hybridization associated with increase in the cultivation of the
domesticated apple Malus ×domestica (Borkh.), threatens the genetic
integrity of M. sylvestris. The present study investigated the number of
hybrids, genetic diversity and genetic structure of 292 putative M.
sylvestris that originate from five different natural M. sylvestris
populations in Saxony, Germany. All samples were genetically analyzed
using nine nuclear microsatellite markers (ncSSR) and four maternally
inherited chloroplast markers (cpDNA) along with 56 apple cultivars
commonly cultivated in Saxony. Eighty-seven percent of the wild apple
accessions were identified as pure M. sylvestris. The cpDNA analysis
showed six private haplotypes for M. sylvestris, whereas three haplotypes
were present in M. sylvestris and M. ×domestica. The analysis of molecular
variance (AMOVA) resulted in a moderate (ncSSR) and great (cpDNA)
variation among pure M. sylvestris and M. ×domestica individuals
indicating a low gene flow between both species. The genetic diversity
within the pure M. sylvestris populations was high with a weak genetic
structure between the M. sylvestris populations indicating an unrestricted
genetic exchange between these M. sylvestris populations. The clear
distinguishing of M. sylvestris and M. ×domestica confirms our expectation
of the existence of pure M. sylvestris accessions in this area and
supports the argument for the implementation of preservation measures to
protect the M. sylvestris populations in Saxony.