Plant cells can be identified from their DNA. To do this, plant tissue needs to be broken up, usually by grinding, to free the DNA.
After this, a buffered saline solution is added to the crushed plant cells. The DNA dissolves in this saline solution and is then purified to separate it from other materials, such as protein and fat molecules. Alcohol is then added to the solution to help the DNA to precipitate out of the solution. Finally, the DNA is retrievable as a long string. It is then analyzed and compared with known DNA fragment databases for identification.