资源植物黑老虎的比较叶绿体基因组学研究OA北大核心CSTPCD

[Objective]This study aims to investigate the chloroplast genomes and SSR loci of Kadsura coccinea,an important plant resource in China,to establish a basis for assessing its genetic diversity and germplasm resources.[Method]The study obtained and analyzed the chloroplast genomes of five individuals of K.coccinea through genetical annotation,nucleotide polymorphism analysis,and SSR analysis using bioinformatics methods.Additionally,the phylogenetic analysis of Kadsura were reconstructed using two Schisandra spp.as outgroups.[Result]The chloroplast genome of K.coccinea showed a typical quadripartite structure,with genome lengths ranging from 145 413 to 145 903 base pairs(bp).The large single-copy region(LSC)spaned from 94 457 to 94 757 bp,while the small single-copy region(SSC)encompassed 18 032 to 18 047 bp.It encodes a total of 125 genes,including 82 protein-coding genes,35 tRNA genes,and 8 rRNA genes.The genome had a total GC content of 39.7%and demonstrated substantial nucleotide polymorphisms(Pi＞0.03)in the intergenic regions of petN-psbM and trnS-GCU-trnG-UCC.A total of 212 single sequence repeat(SSR)loci were identified across the chloroplast genomes of this species.Mononucleotide repeats were the most prevalent,followed by trinucleotide repeats,and pentanucleotide repeats were the least frequent.Among these loci,24 polymorphic SSR loci were found among five individuals of K.coccinea,indicating their potential utility in future.Phylogenetic analysis robustly clusters K.coccinea individuals into a distinct group,revealing no close relationship with other congeneric species.[Conclusion]This study presents the first systematic comparison of chloroplast genomes among multiple K.coccinea individuals.Our findings identified highly variable regions and SSR loci that can be valuable for evaluating the genetic diversity and germplasm resource of this species.