AFLP Analysis on genetic diversity of germplasm resource in Dryopteris fragrans AFLP Analysis on genetic relationship among Rheum tanguticum Rheum palmatum,and Rheum of f icinale Analysis on genetic diversity of different geographical populations of Houttuynia cordata Application of AFLP markers for analyzing genetic difference among cultivated Pinellia ternata Efficiency comparison on polymorphism in Carthamus tinctorius with RAPD and AFLP