to investigation of pathogenisity and genotype diversity of xanthomonas oryzae pv. oryzae (xoo) caused rice bacterial blight, several samples were collected from paddy field of rice in rasht-sangar, soumeh sara, rezvan shahr, daboudasht amol and rice-institute-research guilan during the summer of 2012, from plants that showed blight and yellowing in their leaves. bacterial isolates were identif...