REPEATED SEQUENCE POR6 AND TYPING OF PYRICVLARIA ORYZAE ISOLATES
稻瘟病菌重复顺序PoR6和稻瘟病菌的分型

A repeated sequence, POR6, was proved highly polymorphic in Pyricularia oryzae isolates. The results of pulse field gel electrophoresis and southern hybridization indicated that POR6 sequence was randomly dispersed in P. oryzae genomes with a 30 to 40 copy number. There was no smaller repeated unit discovered within POR6 sequence. POR6-DNA was used as a probe to fingerprint 44 P. oryzae isolates. Based on the similarity of fingerprinting, 22 isolates collected from the north China could be divided into 8 lineages. For some isolates whose infection spectrum had been changed after serial transfers in culture, their corresponding fingerprintings indicated that changes also had taken place in their genomes.