Application of Inter-simple Sequence Repeats (ISSR) Technique in DNA Fingerprinting and Genetic Relationship among Linzhi Mushrooms

Abstract

Ganoderma lucidum is regarded as the herb of longevity. Fungi of this species have been used in folk medicine for hundreds of years, and strains are commercially cultivated for preparation of health tablets. The use of traditional taxonomic methods has been inconclusive in establishing a stable classification of the group, and these methods are useless for characterization of individual strains. In this work, ISSR technique was employed to determine the phylogenetic relationships among 9 G.lucidum, MG1- MG 9 strains using 16 primers.
Of the 16 primers tested, 11 gave amplified fragments. A total of 103 DNA fragments were amplified, of which 89 fragments were polymorphic (86.40%). These 11 primers gave 21 specific amplified fragments in 7 out of 9 strains tested, which can be use as specific markers for strain identification. Interestingly, strain MG3, which had a more distinctive morphology than the rest, had more specific amplified fragments than the others strains. The results of the phylogenic tree indicated that the strains MG3 and MG4 were genetically
distant from the other strains. The results suggest that the ISSR technique is a useful method for polymorphic identification of G.lucidum strains, since it revealed a high degree of polymorphism.