Pathogenicity Differentiation and RAPD Analysis of Curvularia Lunata in Northeast China

26 isolates of curvularia lunata,mainly isolated from corn curvularia leaf spot in 15 different geographic regions in Jilin,Liaoning and Heilongjiang province,which were characterized by differential host and random amplified polymorphic DNA(RAPD).The results indicated that there was abundant genetic diversity and pathogenicity differentiation in these isolates.Two kinds of variation may have a certain correlation.No close correlation was found between genetic diversity and geographic orgins of isolates.The strains for test were identified as five pathogenic types by differential host which higher pathogenic types was distributed widely in Northeast,therefore that could be considered as the dominant pathogenic group.However highest pathogenic types was distributed in Baicheng in Jilin Province,weakly pathogenic types was mainly distributed in Baishan and Lishu in Jilin Province.Eight primers were employed for RAPD analyses of 26 isolates.Out of the 77 RAPD markers,71 polymorphic markers(P=92.2%) were obtain.All isolates were clustered into four distinct groups at similar level of 0.71.Most strains with highest and higher pathogenicity was clustered together,however strain with weak pathogenicity was clustered at lower similar level.