The Phoebe genome sheds light on the evolution of magnoliids.

Lauraceae includes the genus Phoebe, and the family is linked to the evolution of magnoliids. We sequenced the genome of Phoebe bournei Nanmu. The assembled genome size was 989.19 Mb, with a contig N50 value of 2.05 Mb. A total of 28,198 protein-coding genes were annotated in P. bournei. Whole-genome duplication (WGD) analysis showed that Lauraceae has experienced two WGD events; the older WGD event occurred just before the divergence of Lauraceae and Magnoliales, and the more recent WGD was shared by all lineages of Lauraceae. The phylogenetic tree showed that magnoliids form a sister clade to monocots and eudicots. We also identified 63 MADS-box genes, including AGL12-like genes that may be related to the regulation of P. bournei roots and FIN219-like genes encoding GH3 proteins, which are involved in photomorphogenesis. SAUR50-like genes involved in light signal-mediated pedicel or stem development were also identified. Four ATMYB46- and three PtrEPSP-homologous genes related to lignin biosynthesis were identified. These genes may be associated with the formation of straight trunks in P. bournei. Overall, the P. bournei reference genome provides insight into the origin, evolution, and diversification of Phoebe and other magnoliids.

Chloroplast characterizations and phylogenetic position of an endangered orchid, Vanda coerulea (Orchidaceae).

Vanda coerulea possess a high ornamental value and medical effect against glaucoma and cataract. The whole complete chloroplast (cp) genome of V. coerulea and the phylogenetic position based on the cp sequences remain unclear. Herein, we report the complete chloroplast genome of V. coerulea. The chloroplast genome was 149,376 bp in length, including a large single-copy (LSC) region of 86,100 bp, a small single-copy (SSC) region of 11,702 bp, and two inverted repeat (IRs) regions of 25,787 bp. A total of 129 genes were characterized, including 74 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. The overall GC content was 36.6%, and GC percentages range from 27.9% to 43.2% throughout LSC, IRs, and SSC regions. Phylogenetic analysis based on 20 chloroplast genomes of Orchidaceae indicated that V. coerulea is closely related to V. brunnea. Our study provides a valuable resource for the identification and distinction of Vanda genus, and will lay a foundation for further research and conservation measures of V. coerulea.