Valuable Morphological Traits and Genetic Resources of Wild Almond Relatives in Kazakhstan

Wild almond species represent a critical component of Kazakhstan's endemic flora, yet their genetic structure and taxonomic relationships remain largely unresolved.This study provides an integrative assessment of four wild almond species (Prunus ledebouriana, P. tenella, P. petunnikowii, and P. spinosissima) in comparison with the cultivated P. dulcis, combining morphological evaluation and multilocus molecular analysis.Morphological traits, including shrub height, leaf shape, and fruit dimensions, were measured across geographically distinct populations.Molecular analyses employed three nuclear (ITS, s6pdh, KIM) and six chloroplast markers (rbcL, atpF-atpH, trnL-trnF, trnS-trnG, psbA-trnH, psbK-psbI), selected for their proven utility in recent almond studies.The ITS region showed the highest level of polymorphism, with 142 variable sites, followed by cpDNA markers atpF-atpH and psbA-trnH.Phylogenetic trees based on individual and combined datasets revealed consistent clustering of P. ledebouriana and P. tenella as sister taxa, while P. petunnikowii and P. spinosissima formed more distantly related branches.Nucleotide composition and species-specific substitution patterns further confirmed their divergence.In comparison to recent research focused primarily on cultivated almond varieties, this study offers novel insights into the evolutionary dynamics and genetic distinctiveness of wild almond populations in Central Asia.These findings highlight the value of an integrative approach to resolving phylogenetic structure and support future conservation and utilisation efforts for Amygdalus genetic resources.