Comparative genome sequence and phylogenetic analysis of chloroplast for evolutionary relationship among species.

Genus is a widely dispersed genus of conifer plants in the Northern Hemisphere. However, the inadequate accessibility of genomic knowledge limits our understanding of molecular phylogeny and evolution of species. In this study, the evolutionary features of complete plastid genome and the phylogeny of the genus were studied. A total of thirteen divergent hotspot regions ( and ) were identified that would be utilized as possible genetic markers for determination of phylogeny and population genetics analysis of species. Furthermore, seven genes ( and ) with positive selection site in species were identified. Based on the whole genome this phylogenetic study showed that twenty-four species form a significant genealogical clade. Divergence time showed that the species originated about 100 million years ago (MYA) (95% HPD, 101.76.35-109.79 MYA), in lateral stages of Cretaceous. Moreover, two of the subgenera are consequently originated in 85.05 MYA (95% HPD, 81.04-88.02 MYA). This study provides a phylogenetic relationship and a chronological framework for the future study of the molecular evolution of the species.