Isolation of DNA from plants with large amounts of secondary metabolites.

Many plant species have high contents of polysaccharides, polyphenols, or other secondary metabolites that can interfere with DNA extraction and purification. These contaminating compounds can lead to poor DNA yield and prevent access by modifying enzymes, such as restriction endonucleases and Taq polymerase. A number of factors, including choice of plant tissue, tissue preparation, and modifications of the extraction buffer, can help in DNA extraction for difficult plant species. This chapter presents some of the DNA extraction protocols developed for various plants.