RAD-seq of the Stewartia gemmata complex
Qualified DNA samples (total DNA mass > 300 ng, DNA concentration > 10ng/L, and no evident degradation) were delivered to the sequencing institution (Novogene Co., Ltd., Beijing, China) for RAD-seq. DNA samples were fragmented by the EcoR I enzyme. DNA fragments of the desired length were gel-purified before adapter ligation and DNA cluster preparation. The detailed method of RAD-seq can be found in Emerson et al. [56]. The RAD-seq libraries were sequenced using the Illumina HiSeqTM2000 platform (Illu-mina, San Diego, California, USA) to generate 150 bp paired-end reads.