Abstract: In search of a method that was adapt to two-dimensional electrophoresis of Zizania latifolia stem, we compared different methods of protein extraction. Optimized conditions for 2-DE were carried out. The results showed that the protein sample of higher concentration and better quality could be acquired if we made proper changes in extraction of TCA-acetone method. In the process, 10% PVP was added in grinding, the centrifugation time was extended to 20 min and the number of precipitation time increased to 4 or 5, meanwhile, lysate was also condensed. We also decreased errors in protein assaying. During the optimization of 2-DE, changes of sample quantity, process of isoelectro focusing(IEF)and the method of staining became important factors. Compared with coomassie brilliant blue G-250 staining, silver ammonia staining detected much more spots. All of the efforts got a better result with more spots, less streak, clearer background and more unconspicuous tailing．

Key words: Zizania latifolia Turcz., two-dimensional electrophoresis (2-DE), proteome