Relative dominance of Alternaria triticina Pras. et Prab. and Bipolaris sorokiniana (Sacc.) Shoemaker in different growth stages of wheat (T-aestivumL.)

Samples of naturally infected foliar blight leaves of six wheat varieties w ere analysed at five different growth stages For the association of foliar blight pathogens. Only two pathogenic fungi Alternaria triticina and Bipola ris sorokiniana were detected and later was found more frequent. Both the p athogens appeared with the initiation of early tillering but their spread d iffered according to genotype, growth stage and weather conditions. Maximum population of A. triticina was recovered ill the 69th (flowering complete) growth stage while B. sorokiniana was maximum ill the 77th growth (late mi lk) stage. Temperature tip to 26 +/- 1 degrees C and high humidity favoured A. triticina while relatively warm and low humidity conditions favoured B. sorokiniana.