Characteristics of the chloroplast genome and genetic divergence of Tamarix hispida Willd. 1816 (Tamaricaceae)

Abstract

Tamarix hispida Willd. 1816, a crucial native plant species in the arid desert region of northwestern China, plays a significant role in maintaining ecological stability. It is instrumental in addressing soil salinity–alkalinity and heavy metal pollution. This research aims to analyze the phylogenetic divergence pattern and evolutionary history of T. hispida by comparing chloroplast genome structures across different populations. Despite the minimal differences in chloroplast genome structure due to conserved genes and junction regions, sequencing was conducted using the Illumina NovaSeq platform to verify the historical evolutionary processes between different populations, followed by assembly and annotation. The results revealed that the T. hispida chloroplast genome is approximately 156,164–156,186 bp in length, with a quadripartite structure and 131 annotated genes. Phylogenetic analysis indicated two lineages within T. hispida, with a divergence time of 3.15 Ma. These findings emphasize the low genetic diversity in T. hispida and offer valuable insights into its evolutionary past. To effectively protect and manage this species, increased scientific research and monitoring of its genetic diversity are necessary. This study underscores the importance of comprehending the genetic mechanisms behind species divergence to develop informed conservation strategies.

Keywords

• Tamarix hispida
• chloroplast genome
• phylogenetic analysis
• divergence time