The extraction of high-quality DNA from okra (Abelmoschus esculentus L. Moench) is notoriously troublesome due to the high contents of polysaccharides, polyphenols, and different secondary metabolites. We have tested seven extraction buffers on silica dried okra leaves. Here, we describe a simple, rapid and modified procedure for high-quality DNA extraction from okra, which is amenable for downstream analyses. In contrast to Cetyl-trimethyl-ammonium bromide (CTAB) methods, the described procedure is rapid, omits the use of liquid nitrogen, phenol, PVP-10, and chloroform. It also uses inexpensive and less hazardous reagents and requires only ordinary laboratory equipment. The procedure employed a high concentration of Sodium dodecyl sulphate (SDS) to rid the problems associated with polysaccharides and polyphenols. The average yield was between 36 and 45 μg of total DNA from 90 mg of dried leaf weight. The DNA is adequate for molecular analysis of okra, such as genetic mapping or marker-assisted plant breeding. This protocol can be performed in as little as 3 h and may be adapted to high-throughput DNA isolation.
Key words: PVP-10, polyvinylpyrrolidone, non cetyltrimethylammonium bromide, okra, genomic DNA, Sodium dodecyl sulphate (SDS).