Complete Chloroplast Genome of Michelia shiluensis and a Comparative Analysis with Four Magnoliaceae Species

Abstract

Michelia shiluensis is a rare and endangered magnolia species found in South China. This species produces beautiful flowers and is thus widely used in landscape gardening. Additionally, its timber is also used for furniture production. As a result of low rates of natural reproduction and increasing levels of human impact, wild M. shiluensis populations have become fragmented. This species is now classified as endangered by the IUCN. In the present study, we characterized the complete chloroplast genome of M. shiluensis and found it to be 160,075 bp in length with two inverted repeat regions (26,587 bp each), a large single-copy region (88,105 bp), and a small copy region (18,796 bp). The genome contained 131 genes, including 86 protein-coding genes, 37 tRNAs, and 8 rRNAs. The guanine-cytosine content represented 39.26% of the overall genome. Comparative analysis revealed high similarity between the M. shiluensis chloroplast genome and those of four closely related species: Michelia odora, Magnolia laevifolia, Magnolia insignis, and Magnolia cathcartii. Phylogenetic analysis shows that M. shiluensis is most closely related to M. odora. The genomic information presented in this study is valuable for further classification, phylogenetic studies, and to support ongoing conservation efforts.