Bipolaris sorokiniana, a hemibiotrophic phytopathogenic fungus is well-known causal organism of spot blotch disease in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) in warmer and humid wheat growing regions of the world. In present study eighteen isolates were collected from flag leaves of different wheat genotypes and were characterized on the basis of colony colour, pigmentation and exudation, growth pattern, sector and margin. The isolates were grouped in five categories on the basis of colour- olive black, olive cream, greyish cottony, black pink and black cream. Grey group had maximum frequency (38.88%), whereas black cream isolates displayed lowest frequency (5.55%). The present research was undertaken to check the variability among the isolates of the pathogen because day by day new races of pathogen is evolved. Key Words: Bipolaris sorokiniana, Spot blotch, Variability and wheat (Triticum aestivum L.) 

Key Words: Bipolaris sorokiniana, Spot blotch, Variability and wheat (Triticum aestivum L.)