4. Methodology
An extensive survey was conducted during kharif season
of 2012 and 2013 in major rice growing areas of
Bihar for collection of diseased samples of paddy (
leaf as well as seed) to study morphological variability
amongst the isolates of Brown spot fungus,
Bipolaris oryzae. These samples from 25 districts
were used for isolation of desired pathogen from spotted
leaf and seeds with infection of brown spot disease.