RAPD (random amplified polymorphic DNA) markers were generated from filaments of 15 Porphyra lines representing four important groups, P. yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. oligospermatangia . Among the total 69 fragments generated by 6 selected primers (among 50 primers), 67 appeared to be polymorphic (97.1%). Cluster analysis based on the RAPD results was performed. The 15 Porphyra lines were divided into 3 groups. This result was consistent with that from taxonomy analysis. A DNA fingerprinting based on 8 bands amplified with OPN_02 and OPJ_18 was constructed and might be used in Porphyra variety identification. Five specific RAPD fragments of 5 Porphyra lines were isolated and cloned into pGEM_T easy vector. These five RAPD fragments may be useful in germplasm identification and property protection of Porphyra .
