Development of microsatellite (ssr) markers inwalnut (j.regia l.)

In this study, it was aimed to analyze SSR primer pairs based on their amplification and polymorphism in J. regia, which were designed from J.nigra genomic libraries enriched with 'GA' and 'AC' repeats in a previous study. Totally, 99 SSR primer pairs were tested in 'GA' enriched libarary, whereas 241 SSR primer pairs were tested in 'AC' enriched library. Forty-seven (%47.5) SSR primer pairs gave amplification product and 19 of them showed polymorphism in 'GA' enriched library, whereas 44 (%18.3) SSR primer pairs had products after gradient PCR and 13 of them (%5.4) had polymorphism. Totally, 90 alleles were obtained from 19 polymorphic SSR primers in 'GA' library and 66 of them were polymorphic, whereas 81 alleles were amplified from 13 SSR primer pairs in 'AC' library and 32 of them (%39.5) showed polymorphism. In a summary, 32 (%9.41) polymorphic SSR primer pairs were developed in this study and they produced 98 polymorphic alleles in 20 walnut cultivars/genotypes. These polymorphic SSR primers were also tested in a segregating population (Maras-12 X Kaplan-86) and 13 of them showed codominant segregation. In conclusion, these polymorphic SSR primer pairs can be used in the future genetic studies in walnut such as genetic characterization, population genetic, genetic mapping, cultivar identification and germplasm chracterization.