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从NCBI(National Center for Biotechnology Information)数据库下载7 259条菊花相关表达序列标签(EST)序列,经去除冗余序列拼接后得到3 784条Uni-ESTs,总长度为2 088.6kb.用MISA软件查找其简单重复序列(SSR)位点,共获得407个SSR位点,分布于355条EST上,出现的频率为10.76%.在搜索到的EST-SSR中,三核苷酸重复类型占主导地位,所占比例为47.42%.共观察到76种重复基元,出现最多的重复基元是A/T和ACC/GGT,其次为ATC/ATG,AAC/GTT,AC/GT,AAT/ATT.根据搜索结果随机设计了24对菊花EST-SSR引物,对14个菊花品种进行PCR扩增,发现有12对引物有较清晰且稳定的扩增产物(其中10对引物的产物存在多态性),共检出37个位点(其中多态性位点32个),平均每对引物可扩增出3.2条多态性片段.遗传相似性分析显示,14个品种的遗传相似系数在0.61～0.84之间,平均相似系数为0.67.
7259 chrysanthemum related expressed sequence tags (ESTs) were downloaded from the National Center for Biotechnology Information (NCBI) database, and 3 784 Uni-ESTs were obtained after the removal of redundant sequences, with a total length of 2 088.6 kb. A total of 407 SSR loci were found in 355 ESTs with a frequency of 10.76% at the simple repeat (SSR) loci. The trinucleotide repeats dominated the search of EST-SSR , Accounting for 47.42% .A total of 76 repeat motifs were observed, the most common repeat motifs were A / T and ACC / GGT, followed by ATC / ATG, AAC / GTT, AC / GT and AAT / ATT. According to the search results, 24 pairs of chrysanthemum EST-SSR primers were designed at random, and 14 chrysanthemum varieties were amplified by PCR. Twelve pairs of primers were found to have clearer and more stable amplification products (of which 10 pairs of primers were polymorphic) , 37 loci were detected (including 32 polymorphic loci), and an average of 3.2 polymorphic fragments per primer were amplified.Genetic similarity analysis showed that the genetic similarity coefficients of 14 cultivars ranged from 0.61 ~ 0.84, the average similarity coefficient is 0.67.