DNA isolation, PCR amplification, and sequencing
Total genomic DNA was extracted according to the CTAB method reported by Doyle and Doyle (1987). The purity and quantity of genomic DNA were determined by a spectrophotometer (S1000TM Thermal cycler, BIO-RAD) using 1.0% agarose gel electrophoresis against a known concentration of unrestricted lambda DNA. The DNA samples were stored at − 20 °C prior to amplification.