胡萝卜果胶杆菌侵染下半夏转录组中SSR位点信息分析

Analysis on SSR Loci Information in the Transcriptome of Pinellia ternata(Thunb.)Breit Infected by Pectobacterium carotovorum

为开发用于鉴定半夏抗软腐病品种的SSR标记,利用MISA和Excel软件统计分析胡萝卜果胶杆菌侵染下半夏转录组中SSR位点的基元类型、基元组成、出现频率、平均距离等信息。结果表明,在27 252条Unigene中找到符合条件的SSR位点40 621个,出现频率为36.09%,平均遗传距离为2.24 kb。这些SSR标记中二碱基重复是主要重复类型,占总SSR的41.69%,GA/CT、CCG/CGG、AGCT/AGCT、AAAAG/CTTTT分别是二碱基、三碱基、四碱基、五碱基的优势重复单元。序列长度大于20 bp的SSR位点数占23.93%,其中长度大于30 bp的SSR位点数占据比例最多为10.53%。本研究发现,SSR位点的频率高、重复基元的种类多、分布密度大,证明其多态性好。可为后续半夏抗病品种的鉴定、分子育种、进化等研究提供依据。

In order to discover the SSR markers for identification of soft rot disease-resistant varieties of Pinellia ternate(abbreviated as Pinellia ternata).MISA and Excel software were used to statistically analyze the motif type,motif composition,frequency of occurrence,average distance and other information of SSR loci in the transcriptome of Pinellia ternata infected by Pectobacterium carotovorum.The results showed that 40 621 SSR loci were found in 27 252 Unigenes,with a frequency of 36.09% and an average genetic distance of 2.24 kb.Among these SSR markers,dinucleotide repeats were the main repeat type,accounting for 41.69% of the total SSR.The GA/CT,CCG/CGG,AGCT/AGCT,AAAAG/CTTTT were dominant repeating units of two base,three base,four base and five base.The number of SSR loci with sequence length greater than 20 bp accounted for 23.93%,and the maximum proportion of SSR loci with sequence length greater than 30 bp was 10.53%.It was found that loci in the transcriptome of Pinellia ternata had high occurrence frequency,high distribution density,rich variety of repetitive motifs,indicating its good polymorphism.It could provide a basis for the identification,molecular breeding,and evolution of soft rot disease-resistant Pinellia ternata varieties in subsequent studies.