【目的】桂花(Osmanthus fragrans)为我国十大传统名花之一,然而花期短,花型、花色差异小等原因导致其从传统形态学上进行品种鉴定较为困难。基于全基因组序列进行SSR引物的开发,有利于为桂花的品种鉴定、遗传多样性分析等研究提供技术支持。【方法】利用MISA软件对桂花全基因组上的SSR位点进行查找和分析,并使用Primer 3进行引物设计,从中挑选131对引物进行多态性验证。【结果】在桂花全基因组序列中共获得180 838个SSR位点,平均4.10 kb出现1个位点。其中单核苷酸、二核苷酸、三核苷酸为主要的重复类型,分别占SSR总数的42.59%、39.03%和14.13%;二核苷酸重复类型中,以AT和AG基元为主;三核苷酸重复类型中,以AAT、ACC和AAG基元为主。将挑选合成的131对引物在银桂、金桂、丹桂、四季桂4个品种群的32个品种中进行毛细管电泳测序,其中16对位点呈现多态性;单个位点等位基因数为4~16,平均每个位点等位基因数为8.94。【结论】开发的16对桂花SSR引物多态性高,可用于桂花的品种鉴定、遗传多样性分析和指纹图谱构建等方面的研究。

【Objective】Osmanthus fragrans is one of the ten traditional famous flowers in China. However, due to its short flowering period and small differences in flower type and color, it is difficult to identify different Osmanthus varieties through the traditional morphological strategy. In this study, SSR primers were developed based on the whole genome sequence of O. fragrans, which provides markers for variety identification and genetic diversity analysis of O. fragrans.【Method】Utilizing the published whole-genome data of O. fragrans, genome-wide SSR loci were systematically identified using MISA software. The distribution patterns, density, and motif characteristics (repeat unit length, frequency, and type) of SSR loci were comprehensively analyzed. Primer 3 software was then employed to design primers targeting polymorphic SSR regions. Subsequently, the polymorphism and stability of 131 pairs of primers were further verified. 【Result】A total of 180 838 SSR loci were obtained from the whole genome sequence of O. fragrans, with an average of one locus per 4.10 kb. Mononucleotide (42.59%), dinucleotide (39.03%), and trinucleotide (14.13%) repeats dominated the SSR types. Dinucleotide motifs were primarily AT (49.72%) and AG (46.68%), while trinucleotide repeats were predominantly composed of AAT (28.67%), ACC (18.86%), and AAG (13.37%). The 131 pairs of primers were sequenced by capillary electrophoresis in 32 varieties of four groups of Albus Group, Luteus Group, Aurantiacus Group and Asiaticus Group, and 16 pairs of primers were polymorphic; the number of alleles at a single locus was 4-16, and the average number of alleles at a single locus was 8.94.【Conclusion】The 16 newly developed SSR markers exhibit high polymorphism and reliability, providing an effective molecular toolkit for cultivar authentication, genetic diversity assessment, and fingerprint database establishment in O. fragrans.