CLONALITY AND GENETIC-VARIATION IN AMYLOSTEREUM-AREOLATUM AND A-CHAILLETII FROM NORTHERN EUROPE

Genetic variation within and between vegetative compatibility groups ( VCGs) of Amylostereum areolatum (Fr.) Bold. and Amylostereum chailleti i (Pers.: Fr.) Bold. isolates was investigated. DNA fingerprints were made using the M13 core sequence as a primer. A total of 53 isolates o f A. areolatum and 57 isolates of A. chailletii from Lithuania, Sweden , Denmark and Great Britain were studied. In all cases isolates belong ing to the same VCG showed identical DNA banding patterns, suggesting that VCGs correspond to clones. In A. areolatum the vast majority of t he isolates (spread by Sirex juvencus L.) were assigned to dispersive clones, that have wide geographical distribution (i.e. the same genoty pes were detected in Lithuania, Sweden and Denmark), with low genetic variation between the different clones. By contrast, A. chailletii pop ulation structure was consistent with the spread of airborne basidiosp ores produced by outcrossing. Only a small fraction of A. chailletii i solates studied, could be assigned to dispersal clones with a local di stribution, spread by Urocerus gigas L. Overall, M13 fingerprinting de tected low genetic differentiation in both species in the samples we s tudied.