Effect of Chemicals and Bio-agent on Spot Blotch Disease of Wheat (Triticum aestivum L.)

Abstract

Wheat (Triticum aestivum L.) crop in eastern India, suffers with many fungal diseases, namely, Spot blotch (Bipolaris sorokiniana), Alternaria leaf blotch (Alternaria triticina), Curvularia leaf spot (Curvularia lunata), covered smut (Ustilago hordei) and loose smut (Ustilago segetum tritici). Out of these fungal diseases, spot blotch caused by Bipolaris sorokiniana is most important and in badly affected field, the entire plant is blighted. Under favourable conditions the losses may be as high as 20−22%. Studies were conducted at main experimental station of N.D. University of Agriculture and technology, Kumarganj, Faizabad during rabi 2013−2015. Effect of seed treatment and foliar spray with fungicides and T. viride on disease intensity of spot blotch and yield contributing characters like ear length, number of grains/ ear, thousand grain weight, yield and avoidable yield losses were studied. Results showed that the seed treatment with vitavax power @ 3 g kg^-1 of seed followed by two spray of propiconazole @ 0.1% at the time of disease initiation on flag^-1 leaf and at soft dough stage were best and per cent disease intensity (39.03%) was minimum. Maximum ear length (8.22 cm), no. of grains ear^-1 (56), thousand grains weight (51.74 g), yield (42.81 q ha^-1) and avoidable yield loss (29.49) were also highest in this treatment as compared to other treatments. The maximum benefit cost ratio (7.55) was found in seed treatment with T. viride because the cost of treatment was very low.