辣椒花药转录组SSR位点信息分析及标记开发

SSR Site Information Analysis and Marker Development of Pepper(Capsicum annuum L.) Anther Transcriptome

为开发高效实用的EST-SSR标记,对辣椒(Capsicum annuum L.)花药样品的转录组进行测序,去冗余后得到44 832条转录本序列。对所有转录本进行SSR分析,共检测出7 189个SSR位点,分布于5 721条转录本上。SSR位点出现频率为16.04%,平均每7.90 kb检出1个SSR位点。分析SSR位点特征发现,97.80%的SSR重复序列长度在10~30 bp之间,单核苷酸和三核苷酸为主要重复基元类型,各占SSR总数的45.31%和35.99%;全部SSR位点共有159种重复基元,除单核苷酸重复外,AG/CT、AAG/CTT为优势重复基元,分别占SSR总数的9.72%和8.43%。随机选择29对EST-SSR引物在8个供试辣椒自交系中进行扩增发现,引物有效性为93.10%,多态率为17.24%。本研究中开发的EST-SSR标记可为辣椒的种质资源遗传多样性分析、分子标记辅助育种等提供支持。

To develop efficient and practical EST-SSR markers,the study sequenced the transcriptome of pepper(Capsicum annuum L.) anthers to obtain 44 832 non-redundant transcript sequences.SSR analysis was performed on all transcripts,and a total of 7 189 SSR loci were detected,distributed on 5 721 transcripts.The frequency of the SSR loci was 16.04%,with an average distance of 7.90 kb.Moreover,the analysis of SSR loci characteristics revealed that mononucleotide and trinucleotide were the main repeat motif types,accounting for 45.31% and35.99% of the total number of SSRs,respectively.97.80% of the SSR repeated sequence lengths were between 10and 30 bp.There are 159 repetitive motifs in all SSR loci.Excluding mononucleotides,the most abundant motifs were AG/CT and AAG/CTT,accounting for 9.72% and 8.43% of the total SSRs,respectively.Furthermore,twenty-nine pairs of EST-SSR primers were randomly selected and amplified in 8 pepper inbred lines.The primer validity was 93.10%,and the polymorphism rate was 17.24%.The EST-SSR markers developed in this study can provide support for genetic diversity analysis and molecular marker assisted breeding of pepper germplasm resources.