Cultural characterization and cellulase activity of Bipolaris sorokiniana infecting wheat

Abstract

Variability among isolates of Bipolaris sorokiniana was determined based on cultural characteristics. The pathogen was isolated from wheat host from different agro-climatic zones of West Bengal and grown on four different media for investigation of cultural chararacteristics and cellulase activity of this pathogen. The cultural variability showed different characters among the five isolates grown on different media like Potato Dextrose Agar, Carrot Agar, Oatmeal Agar and Potato Carrot Agar. The colour of the colony showed similar type of results on different type of media particularly whitish, greenish which was changed into dull green or dark green with increasing age of the fungal culture in every isolate with a few exception. Five isolates also produced thin to thick cottony growth in every media with a few exception that I2 and I5 produced fluffy growth particularly on PDA media. All the five isolates produced no zonation within the media with a few exception that Alipurduar (I1) and Kisanganj (I2) isolates produced concentric zonation particularly on PDA media and OMA after 6th days after inoculation. The cellulose activity was also different in isolates and maximum being observed in Alipurduar isolate (I1) and minimum in Kalyani isolate (I5).