基于SSR标记的白木香主要品种亲缘关系分析及"分子身份证"构建OA

[Objective]This study employed SSR(Simple Sequence Repeat)molecular markers to assess the genetic diversity among major Aquilaria sinensis cultivars in China and to establish a molecular identi-fication system,thereby providing a theoretical basis for the conservation and authentication of A.sinensis germplasm.[Method]Based on a total of 68 primary domestic varieties of A.sinensis,genomic DNA was extracted from leaf samples,and SSR markers were used to analyze polymorphic loci.Following the prin-ciple of maximizing the discrimination of the greatest number of varieties with the fewest primers,core SSR primers were selected to construct fingerprint profiles and molecular IDs for A.sinensis varieties.[Result](1)A total of 179 alleles(Na)were detected across the 68 accessions using 36 SSR primer pairs,with an average of 4.972 alleles and 2.586 effective alleles(Ne)per locus.The mean values for Shannon's inform-ation index(I),expected heterozygosity(He),observed heterozygosity(Ho),and polymorphism information content(PIC)were 1.079,0.579,0.512,and 0.523,respectively.(2)Genetic structure analysis indicated that the 68 accessions could be divided into two populations(K=2).(3)Based on polymorphism paramet-ers,stepwise primer reduction identified four primer pairs(DRYBMX089,AquSSR29,AquSSR42,and AquSSR59)sufficient to distinguish all accessions.Accordingly,SSR molecular fingerprints and QR code-based molecular identity cards were established for each variety.[Conclusion]The 36 primer pairs suc-cessfully discriminated all 68 A.sinensis varieties.A molecular ID system was established using a core set of four primers,offering both a theoretical foundation and practical support for the molecular authentication of A.sinensis.