In this research, a reliable DNA extraction from different variety of Amorphophallus xiei was developed for RAPD analysis.The results revealed that the high quality DNA was extracted by the modified CTAB method and 8 random primers were used to identify the variety.The way of leaf dividing, the number of bulb and the strips of leafstalk in 9 varieties were analyzed.The results showed the Nei's similarity of coefficients were in the range of 0.440～0.800, the average Nei's similarity of coefficient was 0.714, the maximal similarity of coefficient was 0.008 between clone 1 and clone 8, the minimal Nei's similarity of coefficent was 0.440 between clone 1 and clone 3.These 9 varieties were clustered into 3 groups by UP-MGA analysis.The strips of leafstalk were suggested to be the main index for selected variety in Amorphophallus xiei.

Objective Erigeron breviscapus( Vant. ) Hand-Mazz. is a kind of important Chinese herbal medicine,its natural resource can’t meet the demand of market,so find a substitute from similar speices is an important way to resolve this problem. Methods Using the ITS sequence of Erigeron breviscapus( Vant. ) Hand-Mazz,some species of feverfew ,and other species to construct phylogenetic tree,then to find the difference of homology between the ITS phylogenetic tree of different genus or orders and traditional Phylogenesis,in order to quest the genetic background of Erigeron breviscapus( Vant. ) Hand-Mazz,and carry out some relative experiments or research. Results The phylogenesis in a genus based on ITS was reliable. Conclusion Using ITS to find a similar substitutable species is practical.