A Modified CTAB Method for Genomic DNA Extraction from Apple Fruit

According to the high content of polysaccharides and polyphenols in apple fruits, three modified CTAB methods were used to extract genomic DNA of ‘Granny Smith’, with young leaves as control. The results showed that the method three was the best. This method integrated multiple purification steps, adding the interferent scavenger before cell lysis, increasing the concentration of β-mercaptoethanol and PVP to inhibite the oxidation of polyphenol, and adding 3 mol/L NaAC of 1/10 volume, which effectively removed the polysaccharides, polyphenols and other secondary metabolites. The results of ultraviolet spectrophotometer and agarose gel electrophoresis showed that DNA was high purity and good integrity. The results of ISSR primers amplification showed that the bands were clear. The results of the digestion of EcoR I restriction enzyme indicated that DNA could be digested by restriction enzyme. Therefore, the method three is the best for genomic DNA extraction. This method provides a reference for the removal of polysaccharides and polyphenols in the process of DNA extraction.