Due to interfering components such as polysacharrides, polyphenols, etc, DNA isolation from tropical
plants had been challenging. We developed a safe, universal and efficient DNA extraction method, which
yielded high-quality DNA from 10 tropical plants including cassava, rubber tree, banana, etc. In the
extraction buffer, 2 M NaCl was used to provide a high ionic strength reaction environment,
ethylenediaminetetraacetic acid (EDTA), lauroyl sarcosine (LSS) and cetyl trimethyl ammonium bromide
(CTAB) could inhibit DNase activity effectively, polyvinylpolypyrrolidone (PVPP) produced a deoxidized
reaction environment, and borax enhanced the precipitation of interfering compounds. Ordinary
reagents like β-mercaptoethanol, chloroform and phenol were unnecessary in this protocol, which made
it safe and friendly to use. PCR and EcoR I enzyme restriction digestion results show that the obtained
DNA is good enough for downstream analysis. In conclusion, this protocol is expected to be a preferable
DNA extraction protocol for tropical plants.