Development of 32 novel microsatellite loci in Juglans sigillata using genomic data

Premise A novel set of microsatellite markers was developed for Juglans sigillata (Juglandaceae), an endemic walnut species in southwestern China, to facilitate cultivar identification and future investigations into the genetic structure and domestication history of this species and its close relatives. Methods and Results We developed 32 microsatellite loci for J. sigillata using genomic data and used them to examine 60 individuals from three natural populations. A high level of polymorphism was detected by these primers, with up to eight alleles observed per locus, and an average of four alleles across populations. The levels of observed and expected heterozygosity ranged from 0.000-1.000 and 0.000-0.785, respectively. All but two of the loci were also successfully amplified in three closely related Eurasian Juglans species (J. regia, J. cathayensis, and J. mandshurica). Conclusions The microsatellite loci identified here provide a powerful resource for examining the genetic structure and domestication history of Juglans, as well as identification of its cultivars.