MITOCHONDRIAL-DNA RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS AND PHENETIC RELATIONSHIPS IN NATURAL-POPULATIONS OF THE OYSTER MUSHROOM, PLEUROTUS-OSTREATUS

Restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) in 34 isolates of the oyster mushroom, Plertrotus ostreatus, from throughout the northern hemisphere, were employed to evaluate gen etic relatedness among natural populations. Eighteen isolates were fro m Japan, ten from Europe, Eve from U.S.A., and one from Korea. BamHI, EcoRI and EcoRV digests of mtDNAs produced 18, 19 and 19 distinct RFLP patterns, respectively. By combining all RFLP patterns obtained with the three endonucleases. mtDNAs could be assigned to 22 different clas ses that were clustered phenetically into three major similarity group s, each of which represents a geographically distinct population. The results suggest that geographical distance between natural populations of P. ostreatus is correlated with genetic divergence.