Genetic diversity of Cymbidium kanran detected by Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) markers

Fifty-four Cymbidium kanran cultivars from China, Japan and South Korea were examined and analyzed by using polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) markers to determine their molecular diversity and relationships. In chloroplast (cp) PCR-RFLP analyses, genetic differences were revealed in 4 of 6 primer sets (66.67%) and 19 of 72 primer-enzyme combinations (26.38%), 116 polymorphic bands were detected. For mitochondrion (mt) PCR-RFLP markers, genetic differences were revealed in 2 of 8 primer sets (25%) and 55 polymorphic bands (53.49%) were detected with 7 restriction primer-enzyme combinations. According to the PCR-RFLP marker profiling data, all the cultivars were classified into four groups. The group 1 has included three subclusters that two of them were generally consistent with geography classification. Subcluster 1 and Subcluster 2 were mainly composed of Chinese cultivars. Comparably, Subcluster 3 was composed of two cultivars which originated from Japan separately. Group 2 comprised Huangchengzhiyue and Xiongnu originated from Japan. Group 3 was included in seven Chinese cultivars and five Japanese cultivars. Group 4 was composed of eight Chinese cultivars and four Japanese cultivars. Therefore, we demonstrated that the PCR-RFLP technique could provide a powerful tool for cultivar identification and establishment of genetic relationships of cultivars in cymbidium kanran.