Comparative chloroplast genome analysis of seven extant Citrullus species insight into genetic variation, phylogenetic relationships, and selective pressure

• DOI: 10.1038/s41598-023-34046-6
• Publication Date: 2023-04-25T18:04:19Z
• Authors: Cong Zhou; Putao Wang; Qun Zeng; Rongbin Zeng; Wei Hu; Lei Sun; Shi Liu; Feishi Luan; Qianglong Zhu
• Keywords: Variation (astronomy); Citrullus

Citrullus ecirrhosus, rehmii, and naudinianus are three important related wild species of watermelon in the genus Citrullus, their morphological differences clear, however, chloroplast genome remain unknown. This study is first to assemble, analyze, publish complete genomes C. naudinianus. A comparative analysis was then conducted among seven extant species, results demonstrated that average sizes 157,005 bp, a total 130-133 annotated genes were identified, including 8 rRNA, 37 tRNA 85-88 protein-encoding genes. Their gene content, order, structure similar. However, noncoding regions more divergent than coding regions, rps16-trnQ hypervariable fragment. Thirty-four polymorphic SSRs, 1,271 SNPs 234 INDELs identified. Phylogenetic trees revealed clear phylogenetic relationship developed molecular markers (SNPs rps16-trnQ) could be used for taxonomy Citrullus. Three (atpB, clpP1, rpoC2) identified undergo selection would promote environmental adaptation